Design and Applied Technology (Secondary 4 - 6) · Design and Applied Technology (Secondary 4 - 6)...

Design and Applied Technology (Secondary 4 - 6)

1


2

Design and Applied Technology

(Secondary 4 – 6)

Elective Module 3

Design Implementation and Material Processing

[Teacher’s Guide]

Resource Materials Series

In Support of the Design and Applied Technology Curriculum

(S4 – S6)

Technology Education Section Developed by

Curriculum Development Institute Institute of Professional Education

Education Bureau And Knowledge (PEAK)

The Government of the HKSAR Vocational Training Council


3

Technology Education Section

Curriculum Development Institute

Education Bureau

The Government of the Hong Kong Special Administrative Region

Room W101, 1/F, West Block, Kowloon Tong Education Service Centre,

19 Suffolk Road, Kowloon Tong, Hong Kong

Reprinted with minor amendments 2010

Project Advisor:

Mr. Wong Siu Kai (Head, Department of Engineering, IVE/Tuen Mun)

Author:

Mr. Theo Chan (Design and Technology Teacher)

Project Co-ordinators:

Mr. Li Yat Chuen (Senior Training Consultant, PEAK/VTC)

Mr. Tsang Siu Wah (Training Consultant, PEAK/VTC)

The copyright of the materials in this package, other than those listed in the Acknowledgments section and the

photographs mentioned there, belongs to the Education Bureau of

the Government of the Hong Kong Special Administrative Region.

© Copyright 2009

Duplication of materials in this package other than those listed in the Acknowledgements section may be used

freely for non-profit making educational purposes only. In all cases, proper acknowledgements should be made.

Otherwise, all rights are reserved, and no part of these materials may be reproduced, stored in a retrieval system

or transmitted in any form or by any means without the prior permission of the Education Bureau of

the Government of the Hong Kong Special Administrative Region.


4

PREFACE

A set of curriculum resource materials is developed by the Technology Education Section of

Curriculum Development Institute, Education Bureau for the implementation of the Design

and Applied Technology (Secondary 4-6) curriculum in schools.

The aim of the resource materials is to provide information on the Compulsory and Elective

Part of the DAT (Secondary 4-6) to support the implementation of the curriculum. The

resource materials consist of teacher’s guides and student’s learning resource materials of

each Strand and Module of the DAT (Secondary 4-6) arranged in eight folders.

All comments and suggestions related to the resource materials may be sent to:

Chief Curriculum Development Officer (Technology Education)



Education Bureau

Room W101, West Block, 19 Suffolk Road

Kowloon Tong

Hong Kong


5

CONTENTS

Sections

1. Principles of Curriculum planning 1

2. Concept Map 2

3. Key Concepts 3

4. Teaching Schemes 5

5. Sample Lesson Plans 42

6. Teaching Notes 46

7. Teacher’s Notes for Design and Make Activities 58

8. Teacher’s Notes for Assessment Tasks 64

9. References 72

10. Acknowledgements 75

*Chapters refer to the chapters in the Learning Resource Materials (LRM) of this Module.


1

SECTION 1 – PRINCIPLES OF CURRICULUM PLANNING

This module composes of three chapters which include Materials, Components and Systems,

Processing and Manufacturing, and Computer-aided Manufacturing according to the Design

and Applied Technology (DAT) Curriculum and Assessment Guide (Secondary 4 – 6). Based

on the total allocated lesson time of DAT are 270 hours, no less than 80 hours of which will

be dedicated to coursework. Estimated time allocation for this module is about 65 hours.

Coursework refers to the recommended learning activities included in the Theme-based

Learning Tasks, Design Projects and Assessment Tasks of the Learning Resource Materials

(LRM). Practical and experiential learning are essential components in the module which

enable students to apply scientific and technological knowledge to solve authentic problems.

Talented students can innovate or even invent new products whilst mediocre or less capable

students can make their own technological artefacts under the guidance of teachers using

available resources.

Theme-based learning tasks are the main features in the LRM. Examples and cases relating to

Hong Kong are quoted to enhance students’ understanding of materials. However students are

encouraged to focus on the emerging state-of-art technology in a global sense.

The topics and the expected learning outcomes of each chapter are stated at the beginning of

each chapter in the LRM. At suitable intervals, there will be “STOP AND THINK” and

“HIGHLIGHT” sections aiming to facilitate interactive learning atmosphere and enable

students to explore further knowledge and skills.

In order to assist students to understand the relationship of individual learning elements

instead of treating them as separate entities, the topics in the three Chapters are structured into

four suggested “Teaching Units”. These units are designed to link up similar topics in

sequence. The presentation sequence of the suggested teaching units in this Guide is for

reference only. Teachers may change the order according to their requirements.

Suggested teaching scheme for the ‘Design Implementation and Material Processing’

The time allocation in Section 4 - Teaching Scheme of this Guide is suggested for reference

only. Teachers may adjust the allocation in accordance with their needs. For example, some

coursework sessions involve data collection, literature and information searching, visits and

practice outside the school.

S4 Compulsory part

Coursework S5 Teaching Unit: 1, 2 and 3

S6 Teaching Unit: 4


2

SECTION 2 – CONCEPT MAP

Strand 2: 3.3

Mechanical

Systems

Strand 2: 3.4

Physical Structure

Module 3

Design Implementation &

Material Processing

Topic 1 – Materials,

Components & Systems

Topic 2 – Processing &

Manufacturing

Topic 3 – Computer-aided

Manufacturing

1.1 Properties &

Choice of

Materials

1.4 New

Materials

1.2 Materials &

Structures

1.3

Mechanisms

2.1

Manufacturing

Processes &

Techniques

2.2 Scale of

Production

2.3 Quality

Assurance &

Quality Control

3.1 CNC &

CAM

3.2 Basic

Concepts of

CIM & FMS

3.3 The Impact of

CAM on

Manufacturing

The properties of

selected materials affect

the production method

to be applied

The properties of selected

materials influence the

structure of a system

CAM enhances QA and QC

Production

method

employed

impinges on the

scale of

production

The

advances in

CNC &

CAM make

CIM & FMS

possible

Strand 2: 1.3

Materials &

Standard

Components

Module 5:

Topic 3 - CAD

Module 1: 4.2

Applications

of Robots

Module 1: 3.2

Use of

Programmable

Control Systems

Module 1: 2.4

Applications of

Pneumatic / Electro-

pneumatic Systems

Module 1:

Topic 1 – Basics

of Control Systems

Strand 2:

Topic 2 –

Production

Process

There are links

between this module

and Strand 1 & 3

as well


3

SECTION 3 – KEY CONCEPTS

This section introduces the key concepts of the module.

Key Concept Explanation

Fabrication Fabrication deals with the act or process of forming and assembling

materials, mechanisms and structures.

Forces The forces acting on a structure are either static (not moving) or

dynamic (moving). Static forces are not as destructive as dynamic

forces.

Materials Materials are the basic substances from which an object is made. It

is important that students use a variety of materials when doing

design works and activities. The use of appropriate materials is

linked with other technological concepts. Students should be

exposed to a wide variety of materials and be familiar with the

following properties:

• hard/soft

• brittle/tough

• flexible/rigid

• elastic/ inelastic

• rough/smooth (texture)

• shiny/ dull (finish)

Mechanisms Mechanisms are the parts of a structure that allow it to work or

function. When students understand the basic principles related to

structures, they can begin to include mechanisms in their designs.

Some basic concepts are as follows:

• A mechanism can be used to convert one type of force into

another type.

• Mechanisms can only produce work when energy is

supplied.

• All mechanisms make work easier.

• Mechanisms create motion.

• A mechanism may increase speed of operation

• A mechanism may increase force that it applies.

• Several mechanisms can be combined to form a machine.

• Mechanisms are used because they are versatile and

efficient.


4

Production planning

The production plan for a given product will include:

• a description of details about a product

• lists of materials and components, information and

quantities

• an operation plan which lists out all the operations to be

carried out in sequence, as well as the equipment and time

required for each operation

• Production control identifies how the work is to be

monitored against target performances. Any deviations

from these targets will be questioned and reasoned so that

corrections can be made to kept production operation

smooth

Structures The strength of a structure is more important than its appearance

and cost. If a structure cannot resist the forces that act on it, it will

collapse. The forces which acted on a structure can be one or more

of the following:

• tension

• compression

• bending

• shearing; and/or

• torsion.


5

SECTION 4 – TEACHING SCHEMES

A total of about 65 hours is allocated to cover this module. Out of 65 hours, 20 are used for

coursework in order to enable students to associate theory with practice. An estimated

number of hours required for this module are suggested below:

Design Implementation and Material Processing

(65 hours)

Suggested Lesson Time

(Hours)

Chapter 1

Materials, Components and Systems (30)

1.1 Properties and Choice of Materials 5

1.2 Materials and Structures 6

1.3 Mechanisms 5

1.4 New Materials 4

Coursework 10

Chapter 2

Processing and Manufacturing (20)

2.1 Manufacturing Processes and Techniques 8

2.2 Scale of Production 5

2.3 Quality Assurance and Quality Control 2

Coursework

5

Chapter 3

Computer-aided Manufacturing (15)

3.1 CNC and CAM 4

3.2 Basic Concepts of CIM and FMS 3

3.3 The Impact of CAM on Manufacturing 3

Coursework 5


6

TEACHING SCHEME

1st TERM 2

nd TERM

S4

Compulsory Part + Coursework

Other elective module Other elective module Other elective module

S5

Teaching Unit 1: Products for Living

Topic 1.1 – Properties & choice of materials

Topic 2.1 – Manufacturing processes and

techniques

Theme-based learning activity: PET bottle

Theme-based learning activity: Transformer

toy

Focus: material properties; common

production processes; standard components;

product life-cycle

Teaching Unit 2: Incredible Structures

and Mechanisms

Topic 1.2 – Materials and structures

Topic 1.3 – Mechanisms

Theme-based learning activity: Skywalk at

Grand Canyon

Theme-based learning activity: Water

rocket launch platform

Focus: structural strength; beam and

cantilever; MA and VR; SF and BM

diagrams; gear ratio

Teaching Unit 3: School Open Day

(integrate with the design and make activity of Module 5)

Topic 2.2 – Scale of production

Topic 2.3 – Quality assurance and quality control

Topic 3.1 – CNC and CAM

Topic 3.3 – The impact of CAM on manufacturing

Assessment tasks: CNC machining

Design and Make activity: Open-day gift

Focus: commercial manufacturing processes; CAD/CAM; production

line; quality assurance and quality control

S6

Teaching Unit 4: New Dimensions to

Product Design

Topic 1.4 – New materials

Topic 3.2 – Basic concepts of CIM & FMS

Theme-based learning activity: Shape

memory alloys; Photovoltaics

Practical activity: Racket

Other elective module

Public Assessment


7

SCHEME FOR TEACHING UNIT 1: PRODUCTS FOR LIVING

Introduction

This unit covers the following topics:

1.1 – Properties & choice of materials, and

2.1 – Manufacturing processes & techniques.

Products are closely related to our daily life in different areas, such as clothing, catering, accommodation, transport, education and entertainment.

Students are expected to understand the processes, skills and techniques required to manufacture these products.

Expected Learning Outcomes

At the end of this unit, students should be able to:

� understand the properties of materials, such as strength and durability, and their effects on design

� select suitable materials for particular purposes; consider their working properties and characteristics; tools and equipment available; as

well as the market form, size and specifications of the material available

� know how daily products are manufactured in different methods

� understand major manufacturing processes, such as casting and injection moulding

� select appropriate materials for particular manufacturing processes

� select tools and equipment to shape and form materials safely and accurately, and to finish them appropriately

� consider product life-cycle in order to minimise environmental damage and learn the importance of reusing and recycling issues

� determine whether resources are properly used or not

� know how to ensure their products to achieve standards for intended users. For example, determine how well a product meets functional,

aesthetic and environmental considerations, and suggest modifications to improve their performance, if necessary


8

Teaching Activity I (5-6hrs.)

The following activities provide opportunities for students to:

� apply their understanding of material properties

� identify the methods and processes used to make a product

� understand the manufacturing processes being used in schools

� identify possible shortcomings in design after finalizing materials processing and choice of materials

� describe, analyse and evaluate similar products

� consider possible recycling and disposal methods of the used materials

Unit Objectives Possible Learning & Teaching Activities Resources Remarks

Students should be able

to identify the properties

of materials, components,

and their characteristics

� Teachers are to provide background information and

Students are required to discuss appropriate choice of

materials for a product, e.g. a chair. Students need to

select materials in consideration of exposure to

different environments and discuss why they made

those particular choices, e.g. flexibility of a plastic

product.

In this activity, students will apply their understanding

of materials properties, e.g. the hardness of steel, and

recognise the relationship among properties of materials,

their performance and how they are used.

Topic 1.1

A collection of products such as chairs and

toys. Investigate how different materials and

components are used

Health and safety – Investigate products

with potentially dangerous features, e.g.

sharp edges, handling of parts etc…

should be carefully supervised by a

teacher. The possibility of breakable

products , or components may cause

harm, and should be assessed prior to

using them.


9

� Teachers invite students to examine the functions of

various existing products, for example a robotic toys,

and identify a range of features such as movement,

sound or light. Discuss which materials and

components they are made of, and why these

materials and components were chosen by

manufacturers. Consider the working properties and

functions of them, e.g. mechanical movement,

aesthetic appeal, stability, flexibility, ease of access,

availability, cost, quality of material chosen for the

target market, maintenance and product lifespan.

Through this activity, students should examine how

different parts of a product are shaped and joined;

identify the materials that the toys are made from.

Discuss why particular materials are chosen.

Students should identify

common manufacturing

methods and processes

used to make the

products which are found

in our daily life.

� Teachers will show products that related to different

areas of daily life and discuss with students about:

– cast products such as lamp posts, kitchen tools or a

stapler

– injection moulding products such as trainer soles,

toys, or CD cases

– vacuum-formed products such as food containers or

bubble wrap packaging materials

–

Topic 2.1

Slide shows, video clips or samples of a

range of products

Other than viewing video clips or slide

shows, students can also visit a product

manufacturer to see some of the

manufacturing processes.

Students are required to match each item to a method of

manufacturing. Teacher will also discuss their answers

and explain to students that some products rely on a

combination of methods in manufacturing, e.g. the body

of a kettle might be cast in aluminium, but the handle is

injection moulded and attached to the body with a bolt,

rivet or screw.


10

In this activity, students should be able to name common

manufacturing processes, e.g. casting, injection

moulding, welding, pressing and vacuum forming. They

are expected to match common products to their

production process, for example, a vice body is cast,

and a CD case is moulded.

Students are expected to

study the products by

observing them and

understand their

analytical drawings.

� Students are required to collect product examples

such as cutlery, toys, stationery, food packaging and

containers. (It is desirable to ask them to include

examples or pictures from different times and

cultures/ countries.) Discuss with them the

manufacturing methods and processes used to make

the products. Teachers ask the students to look at a

product from different perspectives and students are

asked to draw the product’s appearance and

annotating features.

Topic 2.1

Drawing materials

Students should collect pictures of some

common production processes as

homework,. These may be photocopies

from books or images downloaded from

CD-ROMs or websites.

Students are encouraged to interview

senior members of their families about

how a product has changed through the

past years, e.g. pens, bicycles, clocks,

telephones, etc., in terms of materials

used and manufacturing methods

employed.

In this activity, students will consider the materials and

manufacturing methods used, and counting the number

of parts and processes used in production. In addition,

they have to describe the relationship between product

design, materials, manufacturing methods and cultures,

demonstrate understanding of how these are changed

over time. Moreover, they should compare similar

products of different prices, and give reasons for the

differences in price.


11

Students should learn to

explore diversity of a

product through

observations and analysis.

� Students are required to collect as many different

samples or pictures of one product as possible to

show the diversity of the product, e.g. assorted board

games. They can then record their findings as

sketches, notes, pictures or charts.

� Teachers introduce students to a case study of PET

bottle. Ask them to compare different examples of

one product that are intended to meet similar needs.

Ask them to identify how the design for end-users

and for manufacturing can conflict with each other,

e.g. cost of materials, and suggest ways to minimise

these problems.

Topic 1.1, 2.1

Theme-based learning task: PET bottle

(Teachers can make use of other suitable

case studies to explain product development

process of a range of everyday items by

means of videos, photographs or books.)

Language for learning when appraising

products – Students are required to work

in small groups to discuss a set of needs

that products might be designed to meet.

They can use flip charts to list out

questions that users might want to ask

about the product, and then rephrase

them into criteria. It would be helpful if

the teacher gives an example first.

In this activity, students should:

– put together criteria and questions that they can

identify about the products and suggest improvements

– appreciate the conflicts and demands faced by

designers and engineers, and reach a practical outcome,

e.g. reconciling function, aesthetics and recycling with

the cost of material

Group presentations to the class will

allow further discussion and refinement

of criteria.

Additionally, students can state why particular materials

are chosen for functional, aesthetic and recyclable

properties, e.g. PET is strong and smooth, and judge

how far a product can fit for its purpose, and whether

resources have been used appropriately.


12

Students should

understand the

importance of reuse and

recycling in design, and

know how to minimise

environmental damage

when selecting materials,

e.g. disposal of plastic

products.

� Students are required to consider, through studying

information about resources such as newspaper and

magazine, how to broaden the selections to meet

requirements or solving a problem. They can consider

whether the resources are worth selecting to meet the

needs, and whether the proposed solution has other

consequences that should be taken into account, e.g.

environmentally damaging by-products from

manufacturing processes and difficulties in safe

disposal of manufacturing by-products. Students may

consider the following questions:

– What happen to the product after use?

– How long will it last?

Topic 2.1

Theme-based learning task: PET bottle

Sample products, e.g. chopsticks which can

be made of (compressed) thermosetting

plastic or (shaped) wood/ bamboo

Learn to read and write specifically

when reviewing texts from ‘Choice’

magazine or Green Power – Students are

required to discuss objectivity and bias

in use of words, e.g. the author’s

standpoint and its effects on meaning.

They can review information of a

manufacturing company and a consumer

group about a contentious issue, e.g. the

use of bio-degradable shopping bag or

food container.

To promote recycling of materials or

reusing product itself, students can

collect recyclable materials, e.g. PET

bottle, and develop a design idea for an

interesting product that can be made

from these materials, e.g. water rocket.

– What factors may limit or lengthen its lifespan?

– How easily can it be recycled?

– Who will pay the cost of recycling?

– What materials have been used and why?

– Where did the materials come from?

– Are the resources likely to run out?

– Is there a problem with side effects, e.g. waste

disposal and pollution?

– What effects will it have on natural

environment?

– Is there any impact that goes beyond the

purpose for which the product is designed for?


13

In this activity, students are expected to discuss a range

of resource issues when designing, e.g. what happens to

a product after it has outgrown its usefulness.

Furthermore, they should understand that choosing the

best materials for a product may not simply mean

choosing the same materials for manufacturing and meet

environmental requirements at the same time.

� Teachers will divide students into groups and give

each group a product which are closely related to

daily life in various areas such as clothing, catering, accommodation, transport, etc. Ask them to brain-

storm the possible benefits, resources, costs and other

consequences, and make a conclusion. Ask them to

report their findings on that particular product.

In this activity, each group of students carries out a life-

cycle analysis of a product (by drawing a flow chart) to

explore its impact on the natural environment of the

extraction, production and disposal of the materials

used. After that, each group presents their findings to

the others. As a whole class, they consider how a range

of products is made, used and disposed of, and identify

their impact on users, other people and the environment.


14

Students should

understand that designers

and engineers have to

take into account

resources, waste disposal,

human health and other

environmental issues

when planning the

production.

� Teachers will explain to students that many

manufacturing industries use huge quantities of raw

materials and resources, e.g. electricity, water, and

produce waste products. Discuss how the impact on

the environment can be minimised when

manufacturing products. Discuss with students the

values issues relating to sources of materials, e.g.

finite resources and reuse of materials. Students are

required to what steps they think can be taken to make

manufacturing more environmentally friendly.

Topic 2.1

Photos or video clips showing the extraction,

use and eventual disposal of some materials

used in manufacturing

After going through the activity, students need to list out

several ways a manufacturer can make its product more

environmentally friendly, e.g. reducing waste, reducing

materials used and reducing energy used, planning to

reuse parts.

Students should learn that

useful information can be

gained by analysing

existing products that are

similar to the one they are

designing; and products

are designed to meet

particular consumer needs

and are also influenced by

manufacturing constraints.

� Teachers can organise a class collection of games or

toys. Students are required to analyse the novelties by

sketching them, describing how the shape and

packaging have been made. Explain how a product

development should respond to the needs and demands

of consumers in order to maintain sales, e.g. meeting

the demand for products that are environmentally

friendly. Discuss with students how the products are

made to meet consumer’s needs.

In this activity, students will analyse a product against a

set of design criteria. Their discussions will be recorded

in note form. They will then need to develop the notes

into a short analysis (say 150 words), with subheadings,

a short paragraph for each criterion and a final paragraph

illustrating their overall analysis and recommendations

for improvement. Students can phrase the subheadings

as questions, e.g. What is the outlook of the product?

Topic 1.1, 2.1

Theme-based learning task: Transformer toy

(Teachers can make use of other suitable

examples to explain the process of product

analysis.)


15

How does the finish look like? How much does it cost?

Who would buy it? Besides, students should describe

how a product design is influenced by manufacturing

constraints, e.g. reducing the number of parts for ease of

assembly.


16

Teaching Activity II (5-6hrs.)

The following activities provide opportunities for students to acquire new skills that will

benefit their design skills and will engage in activities like the following:

� use ICT to search information regarding properties of various materials and

processes

� understand the properties and working characteristics of materials and components

� use a wide range of hand-tools and machine-tools

� apply suitable finishing processes to different products

Unit Objectives Possible Learning &

Teaching Activities Resources Remarks

Students should

learn to use ICT to

seek information

on materials and

processes from

digital sources.

� Teachers will demonstrate

how to use ICT to search

for source material to help

them when designing, e.g.

accessing databases for

information on materials,

processes and products.

In this activity, students will

use appropriate searching

methods and obtain accurate

and relevant information

about materials and

processes, e.g. how PVC is

produced, from a range of

digital sources.

Topic 1.1

Useful website:

www.materialise.com

Use of ICT –

There is an

opportunity to use

databases when

identifying

information about

materials and

manufacturing

processes.

Students should

learn to explore

materials with

different

properties by a

variety of

processes, to find

out about their

working

characteristics.

Students are required to

explore the behaviour of

materials during particular

processes, e.g. heating,

forming and reforming.

Discuss the impact on the

end product and how the

physical properties can be

used to achieve particular

results/ effects when

designing and making. For

example, teachers can set

up a range of tasks to show

how to bend and form

Topic 1.1, 2.1

Equipment for material

processing, e.g. strip

heater and vacuum

former

Health and

safety – Students

should be

reminded about

hazards, risks and

risk control when

using all tools and

equipment. They

should be asked to

explain how they

are managing their

workspace to

ensure the health

and safety of


17

curves in sheet materials, to

give students a practical

understanding of the

rigidity/ flexibility

possibilities.

themselves and

others, and to

explain the steps

they have taken to

control risks.

They should also

be reminded how

to use information

on tools,

equipment and

materials to assess

immediate and

cumulative risks.

All appropriate

health and safety

regulation notices

and signs should

be displayed and

explained to

students.

Moreover,

teachers must

carry out a health

and safety risk

assessment.

� Extended activity:

Students are required to

experiment with different

combinations of materials

for different purposes, e.g.

to laminate wood with

plastic to give it a hard-

wearing surface.

In this activity, students

need to demonstrate how to

process materials, e.g.

shaping, forming and line

bending, to make best use

of their working properties.


18

Students should

learn to apply

their knowledge of

the properties of

materials, e.g.

strength and

durability, to

influence what

they select for

a design.

� Teachers will discuss with

students how to select

materials and analyse the

working properties, func-

tional characteristics,

aesthetic quality, cost, and

appropriate processes.

Discuss how selection of

materials often involves

reconciling conflicting

demands, e.g. strength

versus overall weight of a

product. Discuss methods

of testing those materials,

e.g. making scale model

or using computer

software to undertake

testing of materials.

Topic 1.1, 2.1

Material testing

equipment

For testing

material, it is

desirable to work

with suitable

software.

Through this activity,

students need to consider

several criteria when

selecting materials, e.g. to

choose the material within a

price range that best meets

the function and aesthetic

qualities required. In

addition, they need to test

materials against a

specification before going

into production, e.g. to

check raw materials for

flaws, faults or degradation.


19

Students should

learn to make

prototypes,

models and mock-

ups when

designing and

making.


how to produce

prototypes, models and

mocks-up in a variety of

materials, e.g. use

mouldable materials to

shape a chess-man, use

cardboard to model pieces

of a puzzle, use of

construction kits and

scrap materials. Teachers

will also need to introduce

examples of how

manufacturers have used

prototypes, models and

mock-ups during the

process of design and

making, and give reasons

why these are used.

After practice of modelling

techniques, students should

know how to make their

own prototypes, models and

mock-ups, e.g. a cardboard

box of a game, and should

know when these will be

most useful, e.g. comparing

different design ideas.

Topic 1.1, 2.1

Materials for modelling

If possible please

collaborate with

Module 5. Students

can be assigned to

find examples of

how prototypes,

models and mock-

ups (with a variety

of materials) are

used.

Students should

learn how to use

machining,

forming and

casting safely and

effectively.


to the students several

manufacturing methods

such as machining metal,

casting resin and forming

plastics. Discuss

appropriate and safe use

of equipment. Allow

students to practise

processes by making

simple projects.

Furthermore, teachers

need to provide the

students with an

opportunity to compare

Topic 2.1

Equipment for material

processing, e.g. lathe

and milling machine


20

different methods of

making the same product

and to discuss how the

method chosen will affect

quality, cost, time taken,

tools, equipment and level

of expertise needed.

In this activity, students will

use available equipment

safely and effectively to

produce a simple item and

select a process to achieve a

particular outcome.


21

Students should

learn about

finishing and

decoration and its

impact on a

product’s

performance and

the environment.


to students a range of

finishing techniques, e.g.

electroplating, dip

coating, painting,

polishing, and discuss

their respective

applications. Teachers

will also discuss with

students the difference

between improvement of

appearance and

performance. The content

will also need to include

environmental impact and

health hazards of different

finishing techniques.

At the end of this activity,

students need to identify and

practise common finishing

processes, e.g. enamelling,

dip coating, staining wood,

electroplating. In addition,

they need to be able to

evaluate benefits and haz-

ards when using different

techniques, as well as their

effect on quality before

deciding which one to use,

e.g. students have to choose

between various painting

and polishing, and explain

why they prefer to use a

particular technique.

Topic 2.1

Tools, equipment and

materials to practise

finishing techniques

Students are

required to

investigate

different finishes

and surface

decorations used

on a variety of

materials and

describe how they

alter performance

characteristics.


22

SCHEME FOR TEACHING UNIT 2 - INCREDIBLE STRUCTURES

AND MECHANISMS

This unit covers the following topics:

1.2 – Materials and structures and

1.3 – Mechanisms.

Students should be able to apply their understanding of structures when designing, and be

able to select suitable materials for the task. They will also acquire knowledge of mechanisms,

skills and techniques that are required. This unit is expected to take 12–15 hours and can be

taught in the first term of S5 for ensuring progress of better understanding on structures and

mechanisms.

In this unit, there is a design project that gives students opportunities to show how well they

can work cooperatively and how much they are able to apply their knowledge and experience

learnt at S4. In this project, students will have to participate in designing an activity on the

theme ‘Water Rocket Launch Platform’. They will work as a team to test out different

structural designs on how the platform can withstand greater loading and to identify various

mechanisms to move the loads. They will also design and build a (transportable) platform

from which water rockets can take-off.


At the end of this unit, most students will:

� learn how structures can fail when loaded, and investigate techniques to reinforce

and strengthening them, e.g. through triangulation, by bracing with struts and ties

� measure and calculate the forces of tension, compression and shear throughout their

designs

� use a wide range of mechanisms, e.g. gears, levers, etc. to move a load

� measure and calculate the MA, VR and efficiency of their designs / machines

� devise tests to check the quality of their works at critical points

� clarify their ideas through discussion and modelling and give reasons for choosing

between ideas

Teaching Activity I (4-5hrs.) The following activities provide the opportunities for students to:

� learn about different types of man-made structures

� consider safety factors, such as Young’s modulus, etc. when designing structures

� find out how to draw BM and SF diagrams of beams and cantilevers

� understand how mechanisms used in various products

� describe and analyse products in terms of MA, VR and efficiency


23

Unit

Objectives

Possible Learning & Teaching

Activities Resources Remarks

Students should

understand

several types of

man-made

structures.

� Students are required to compare

load-bearing structures used for

various type of chairs, and

investigate how they deform under

load.

� Students are required to investigate

structures used to carry and protect

vulnerable items, e.g. packaging of

goods, casings for electrical items.

Topic 1.2

A collection of

products, e.g.

chairs, cartons and

vacuum-formed

plastic casings

Slide show, video

clips or models of

assorted buildings,

e.g. framed/ mass/

shell structures

Health and safety –

Investigative activities

which involve products

with potentially dangerous

features, e.g. sharp edges,

should be carefully

supervised by a teacher.

The possibility of products

breaking during inspection,

or components causing

harm, should also be

assessed.

In this activity, students should

identify and describe 3 main types of

structures:

– mass structures

– framed structures

– shell structures

The features of these structures and

how they are used will be also

discussed in the class.

Students are required to collect

pictures of local buildings / structures

and group them into categories, i.e.

mass, framed or shell ones. These may

be photocopies from books or images

downloaded from CD-ROMs or

websites.

Students should

understand that

designers and

engineers have to

take into account

safety factors,

such as Young’s

modulus, BM

and SF, cross-

section of

members, etc.

when designing

structures; and

the methods to

reinforce

structures.

� Teachers will introduce students to a

case study of the Skywalk at Grand

Canyon. Ask them to identify the

aspects that are vital to such

incredible structure.

� Teachers will show students typical

structures of beams, columns and

cantilevers. Explain how to find out

the external and internal forces of a

loaded structure, and its associated

BM and SF diagrams.

� Discuss with students methods of

reinforcing such structures.

Topic 1.2

Theme-Based

Learning Task:

Skywalk at Grand

Canyon

Sample structures

of beams, columns

and cantilevers

Exercise of

structures

Teachers can make use of

other suitable case studies

to look at various structural

designs by means of

videos, photographs and/or

books.


24

In this activity, students are likely to:

– put together criteria and

questions that they can use

to appraise the case and

suggest improvement

– understand the conflicting

demands faced by designers

and engineers, e.g.

reconciling function and

aesthetics with the strength

of a structure

– point out different aspects of

a structure, e.g. cross-section

of members, BM and SF,

that are vital in designing

structures

– identify methods to

reinforce and strengthen

structures, e.g. through

triangulation or by bracing

with struts and ties

Students should

be able to realise

the application of

mechanisms in

daily life.

� Students are required to examine a

range of products, e.g. toys and tools,

in which different types of

mechanism are used.

� Discuss with students the functions

and efficiencies of those mechanisms

by finding out their MA and VR.

In this activity, students look into the

uses of various types of mechanisms in

different products. They have to

describe the products in terms of their

MA and VR. Moreover, they need to

compare efficiencies of similar

products with the same function.

Topic 1.3

A collection of

products, e.g. toys

and tools, in order

to demonstrate how

various mechanisms

are used

Exercise of

mechanisms

Teaching Activity II (4-5hrs.)

The following activities provide opportunities for students to acquire new skills they need to

work on their design and participate in the activity assigned, for example:

� apply the concept of strength and stiffness of a structure when designing, e.g. loads

exerted on the members of a structure

� apply mechanisms for lifting and moving loads

use wide range of tools, machines, kits and techniques to fabricate models of simple structures

and mechanisms


25

Unit

Objectives

Possible Learning & Teaching


Students should

learn to consider

different

structural designs

to withstand

greater loads, use

common

materials to

make models of

structures, and

carry out fair test

procedures.

� Teachers will examine different structures

with students, e.g. structures used in

frameworks, and ask them to identify

forces acting upon the structure.

� Students are required to compare structures

used in a range of products such as tents

and chairs, and to identify criteria for

choosing different structures for different

purposes.

Topic 1.2

Practical tasks

Sample structures

Materials to make

models, e.g. balsa

wood, cardboard or

foam board

Tools and

equipment to carry

out tests

It is desirable to

involve ICT

resources for

collecting, analysing

and presenting data.


Correct procedures

should be written

down, demonstrated

and followed when

testing structures.

Some tests may carry

significant risks and

teachers should judge

when it is appropriate

to use them. Students

should be taught to

manage their

environment to

ensure their own and

others’ health and

safety.

� Teachers will demonstrate how to make

models of structures using a variety of

materials and how fair tests can be carried

out.

� Teachers will divide students in groups and

instruct them to investigate the effects of

loads on various types of test structures of

different materials, to see how the

structures deform under load and the way

in which they fail.

–

In this activity, students are expected to:

– describe different structural

designs to withstand loads

– explain how products can be

designed to distribute the forces of

tension, compression and shear

(with the help of BM and SF

diagrams)

– carry out simple tests for

properties of materials, e.g.

durability, elasticity

– know that excessive loads can

cause structures to fail by bending,

buckling and twisting

making models,

e.g. construction

kit


26

Students should

learn to use

various

mechanisms to

lift and move

loads, and use

models of

mechanisms for

evaluation.

� Teachers will examine various mechanisms

with students, e.g. those used in lifting

machines, and ask them to find out their

features such as MA and VR.

� Teachers will demonstrate how to make

models of mechanisms with kits or

common materials.

Topic 1.3

Sample

mechanisms

Materials of

Measuring

Instrument

Mechanism of a

capsule toy vending

machine is requisite

in Unit 3.

� Teachers will ask groups of students to

fabricate models of mechanisms used

inseveral mechanical systems, e.g. a crane

or a vending machine.

In this activity, students have to:

– analyse various mechanisms with

different functions

– calculate MA, VR, efficiency and

torque of a mechanical system

– construct models to evaluate

feasibility and efficiency of

correlated designs

Teaching Activity (4-5hrs.)

With the use of project guidelines, information sheets and other aids, teachers will assign

students a design project (a group project) – Water Rocket Launch Platform. In this project,

students have to:

� fabricate structures to hold a water rocket supported by a platform

� construct mechanisms to erect the structure which hold the water rocket and make

the platform structure movable

� select materials according to their characteristics and match them with appropriate

processes

� use a range of manufacturing techniques, tools and machines to cut, shape and form

materials safely

� assess design solution against the original design specifications

* Teachers can choose different themes that related to structures and mechanisms for the

design and activity.


27

Unit Objectives Possible Learning &

Teaching Activities Resources Remarks

Students should learn to

work in groups to design

and make a water rocket

launch platform and

applying knowledge, skills

and understanding they

developed during the

research/ investigative

activities and hand-on/

practical activities.

Students are motivated to design

and make several water rocket

launch platforms. Students are

required to search for the pictures

of rocket launch platforms used in

different countries such as China,

Russia and United States (see

figure below).

The making of water rockets is the

extended work of the case study of

PET bottle in Unit 1. Through the

project, students:

– apply the concept of

strength and stiffness of

structure in design

– utilize mechanisms for

lifting and moving loads

Project guidelines,

information sheets

and worksheets

Sample structures

and mechanisms

Materials for

modelling,

construction kits

An outdoor activity

can be arranged for

students to

demonstrate how to

move, erect and

launch their water

rockets. This may be

a cross-curricular

program on school’s

Open Day presenting:

� the concept of

action and

reaction (Science)

� our country’s

greatest

technological

achievement

(Liberal Studies)

– prioritise and settle

decisions on materials,

components, time and

production with the help

of modelling/ testing

– use materials and

components

understandingly

– manipulate tools and

machines safely

– assess their product

against the original

design specifications

Rocket launches platform model


28

SCHEME FOR TEACHING UNIT 3 - SCHOOL OPEN DAY

This unit aims to introduce the concept of designing for manufacturing, and the main enterprise activities that are used by manufacturers. It

includes the following topics

2.2 – Scale of Production,

2.3 – Quality Assurance & Quality Control,

3.1 – CNC & CAM

3.3 – The Impact of CAM on Manufacturing.

The emphasis is on thinking about how a product will be made as an integral part of the design process, rather than as an afterthought once the

design is complete. It is expected to take 20 to 24 hours and will be used in the second term of S5 for ensuring progression in better

understanding about manufacturing. Besides, it is designed to help teachers to understand their students’ abilities and to give students a

motivating insight into enterprise activities.

In this unit, there is a design project that provides students opportunities to show how well they can work cooperatively and how much they are

able to draw on knowledge of a range of manufacturing processes and techniques developed in this module. In this project, students will have to

participate in a design and participate in an activity on the theme ‘Open-day Gift’. It is set in the context of a mini-enterprise project. Students

will work as a team, identifying different roles for team members, design and make a product in large quantity, reflecting similar processes can

be used commercially. Moreover, they will need to develop quality assurance procedures, and use jigs, moulds and CNC machines, when

appropriate, to improve quality.


At the end of this unit, most students will:

� learn what is meant by ‘one-off’ and ‘high-volume’ production

� learn that making identical parts in a batch can be cost effective and ensures accuracy

� design and make a product that is suitable for manufacturing in large quantity


29

� understand the importance of quality assurance and control

� learn how quality assurance systems, e.g. inspection and testing, using jigs, moulds and templates, are used during the design stage to

plan safe and accurate production

� how CNC machines are used in industry

� give reasons for their choices of roles within a team

� describe how team members can be organised to suit their skills and abilities

� work from detailed plans that they have made

� adapt their methods of manufacture to changing circumstances that batch or volume production requires

Suggested Teaching Scheme I (6-7 Hrs.)

The following activities provide opportunities for students to:

:

� investigate different scales of production

� understand how some processes used in school are the same as those used in industry

� understand how CNC machines/ systems are used in industry for design and manufacture

� find out how ICT influences manufacturing in industry and has an impact to people’s lives


30


Students should understand how

everyday products are made, how

identical products are achieved at the

end of a complex production process,

and why these products are often

cheaper than if we were to buy the raw

materials and to make them ourselves.

� Teachers will discuss with students how items

similar to those used for the design and make

activity (design project) are produced cheaply

and in quantity so that they all come out the

same. For discussion sessions, students can be

asked the following questions:

– What kind of materials, tools, equipment and

processes are most suitable when a large quantity

of an identical products is made?

– How serious will it be if one product is below

standard?

Topic 2.2

A collection of capsule toys/ gifts, e.g. key

fobs and magnetic memo holder

In this activity, students need to apply their

understanding of various manufacturing processes

and are expected to describe what must be done to

ensure that identical item are made, when

manufacturing in large quantity.

Students should learn that some small-

scale processes used in school are the

same as those used in industry for

high-volume production.

� Teachers will discuss with students what

specialised tools such as jigs and fixtures and

equipment can be used to simulate small-scale

processes and high-volume production, e.g.

casting, injection moulding, vacuum forming.

Point out how this is the same as those used in

manufacturing industry. If it is different, ask

them: “Why do you think this is?”

Topic 2.2

Slide show, video clips of several commercial

manufacturing processes

Hand-operated injection moulding equipment,

vacuum former, etc.

At the end of this activity, students are likely to be

able to describe two examples of the process used in

school are the same as that in industry.


31

Students should be able to tell how

different products are made as a one-

off or in high volume and how to

compare one-off and high-volume

products.

� First, teachers will discuss with students about

how well particular products are suitable to be

manufactured in large volume.

� Discuss how different products are made in

different ways, e.g.

– a cupboard or work surface in a kitchen might be

specially made to fit an awkward space (a one-

off)

– ball-point pens are made in vast quantities and

each one that comes off the production line is

exactly the same as the others (high-volume

production)

Topic 2.2

Samples of one-off produced items and mass-

produced items

� After that, students are required to compare

hand-made and high-volume products using

these questions:

– How is the product designed so that it is suitable

for small-volume or large-volume production?

– What are the costs of the materials, labour, tools

and equipment needed to make the product?

– Are the tools and equipment used to make the

product specialised or serve general purpose?

In this activity, students are expected to describe

one or two differences between a one-off and the

production products in a large quantity, and give

four examples for each of them. Besides, they need

to compare one-off and large quantity products in

terms of differences, e.g. design features, cost, tools

and equipment used, quality.


32

Students should learn how a

production line is made up of

members with particular roles and

responsibilities.

� Teachers will discuss with students the different

roles required to run a successful production line.

� Students are required to discuss the best roles for

each team member, e.g. supervisor, accountant,

inspector, worker, etc. and what the main tasks

for each might be.

Topic 2.2

Worksheets

� Students are required to think about each other’s

skills and abilities, but remind them that the roles

need to be flexible because of varying

workloads.

After this activity, students are able to list the main

roles and responsibilities of three different members

on a production line, and decide which role will suit

which team member, according to their skills.

Students should realise how CNC sys-

tems/ machines are used to produce

items and the benefits and

disadvantages of using them.

� Teachers need to point out the special features of

CNC manufacturing systems

� Discuss with students the advantages and

disadvantages of using CNC, e.g. reducing waste

as a result of accurate estimation of materials

needed, achieving higher efficiency, reducing

human control, reducing risks, reducing tedious

or repetitive tasks, speeding up laborious tasks,

ensuring quality and accuracy, easily repeatable

products, automation, team working, faster

production, impact on labour supply, ability to

monitor, ability to respond to demand and sales

in shops.

Topic 3.1

CNC systems/ machines

Divide students in small groups

and ask them to list benefits

and disadvantages of

computer-controlled

manufacture. The groups can

then come together and debate

informally about the issues. It

is helpful to have a chair and a

note taker who can report to the

whole class about the

conclusions.


33

In this activity, students will point out when CNC

systems/ machines are being used and give simple

explanations for why they are used, e.g. to make

production quicker, to respond to sales more

quickly.

Students should learn why designers/

engineers use CAD/CAM in their

work and recognise the differences

between products that are designed

using CAD/CAM and those that are

not.

� Teachers will show students a video or

photographs of designers/ engineers using

CAD/CAM in a variety of situations and for a

range of products. Discuss the benefits for their

work, e.g. it is easier to change a design, you can

store design elements in a library, you can get

information about manufacturing (how long it

will take, how much it will cost and so on).

� Students are required to evaluate a product that

was designed and made by using CAD/CAM

Topic 3.1

Sample products made by hand and

CAD/CAM respectively

If possible invite a designer/

engineer to come and talk to

the students.

This activity could be carried

out collaboratively with Topic

3 – CAD, of Module 5.

Students will compare the differences between

products that are being designed and made by using

CAD/CAM, with those that are not, e.g. quality

drawings, accuracy, cost, speed, ease with which

changes can be made, ease of working as a team,

etc.

Students will learn how CAM

influences the manufacturing industry.

� Teachers will lead the students to visit a local

company to see how a product is designed and

manufactured, and how CAM influences the

manufacturing industry.

� Video or slide presentation are introduced to

students if visit to local company is not feasible.

Students are encouraged to visit websites of

different manufacturing companies.

Topic 3.3

Students will need to take notes

when listening to a speaker,

they can refer to the

information later when

working with their design

projects. Students can discuss

the key areas of interest in

groups or as a class.


34

In this activity, students are expected to discuss how

a local company produces a product, e.g. what it

makes, the materials, tools and equipment that it

uses, including CAD/CAM.

Students will learn how local

manufacturing industry has changed

over time.

(extended/ optional activity)

� During the 60’s to 70’s, manufacturing industry

in Hong Kong was blooming. Students are

required to find out what products were produced

in the local area, where were the resources came

from, and where the products went to. Discuss

with them why many companies go for

international manufacturing and set up factories

in different countries.

Topic 2.2

Documentary films of local manufacturing

industry

At the end, students are able to describe the history

of manufacturing industry in the local area, and

explain how it has been changed since 80’s. They

are also expected to name one product that is made

in the local area and name the company that makes

it.

Teaching Activity II (6-7 Hrs.)

The following activities provide opportunities for students to acquire new skills they need for the design and make activity, for example:

� use CAM to make simple items

� how simple quality assurance system(s) and quality control procedure(s) are used

� how to use ICT to gather information about the making process


35


Students should learn how to break

down production plan into simple

stages and represented them in a

flow chart.

� Students are required to describe how a product is

made, by breaking the process down into tasks and

draw a simple flow chart.

Topic 2.2

Sample products, e.g. memo holder

and key fob

Worksheets

Students should learn how to use

CAD/CAM equipment safely

� Teachers will demonstrate to students how they can

use CAD/CAM equipment to design and make items,

for example:

– how to use CAD software to draw ideas and model in

2-D and/or 3-D

– how 3-D modelling software can create realistic

representations of a finished product, e.g. a toy

– how to use 2-D draw/paint programs to produce

images, such as promotional graphics, and apply to the

surface of container, e.g. a capsule

– how to use 2-D draw/paint programs to produce a

pattern or template that can be printed out to ensure

accurate making, such as a pattern or net showing the

position of folding line

– how to use plotter/cutters to produce full-size patterns

or nets in thin sheet material, e.g. paper or PVC

– how to use CNC machines to make simple products

� Advise students on safety and technical issues.

� provide students an opportunity to practise these skills

by making simple items, e.g. a key fob, name plate,

simple container, personal adornment.

In this activity, students:

- use CAD software and follow instructions to set up a

Topic 3.1

CAD/CAM equipment and relevant

training manuals

This activity can be carried out

collaboratively with Topic 3 – CAD,

of Module 5.

A variety of CAD/CAM equipment is

available in the market, each has its

features and limitations. However,

essential techniques should be

considered, for example:

- how to use toolpath simulation to

check a CNC toolpath for safety and

efficiency

- how to save designs in a file format,

e.g. DXF (data exchange file) that can

be imported into specific software for

manufacturing


36

CNC machine

- use CAM machinery safely to make a simple item

Students should learn about the

differences between one-off and

high-volume production, and the

meaning of continuous and

repetitive flow.

� Teachers will ask groups of students to make a batch of

identical, ready-designed products, e.g. key fobs made

from acrylic sheets or items related to the design

project, using different methods:

– an individual working with hand tools

– an individual using jigs, templates, etc.

– a group working as a production line

– an individual using CAD/CAM

� After that, teachers will discuss with students several

ways of making a product in high volume, or use case

studies to discuss how production can be faster, more

cost effective and of a higher quality.

In this activity, students need to give examples of how a

manufacturer can produce an item more quickly, more

cost effectively and/or of a higher quality. Besides, they

must be able to explain why it might be appropriate to use

CAD/CAM rather than hand-tools, e.g. can be cost

effective and can ensure accuracy.

Topic 2.2, 3.1 and 3.3

Working/ production drawing

Hand tools

CAD/CAM equipment

Students will learn that repetitive

quality can be assured with CAM,

accurate measuring, inspection and

testing, and with the use of jigs,

moulds and templates.

� Teachers will discuss with students, or use examples to

show, various ways of achieving high quality when

manufacturing a product by implementing quality

assurance at all the stages of production, e.g. accurate

measuring, inspection and testing, using jigs, moulds

and templates, using remote control devices such as

CAD/CAM equipment.

� Explain the difference between ‘Quality control’,

where the product is checked at the end of the process,

and ‘Quality assurance’, where thorough checking of

the process to ensure that quality is achieved at the end.

Topic 2.3, 3.1 and 3.3

Measuring tools, jigs, moulds and

templates

CAD/CAM equipment

Sample products


37

In this activity, students will describe what is meant by

‘Quality assurance’ and ‘Quality control’ and give an

example of each.

� Teachers will demonstrate how accuracy and quality

can be achieved, e.g. using a template, jig or

CAD/CAM.

In this activity, students use CAD/CAM or other

appropriate manufacturing aids to ensure that all parts of

products are identical when a number of the same item are

designed and made.

Students will learn how to use ICT

to manage their design projects.

(extended/ optional activity)

� Teachers will demonstrate to the students how ICT can

help them to design and make batch-produced items,

and will also discuss when it is appropriate to use ICT,

e.g. using spreadsheets to help with ‘scaling up’ or

costing.

� Students are required to practise their ICT skills, for

example:

– how to use software programs to plan steps in the

making process, e.g. a Gantt chart

– how to use a digital camera or video to record a

making process for others to follow

In this activity, students use ICT to manage a project and

present production systems or instructions for others to

use.

Topic 2.2 and 3.3

Project management or planning

software

AV equipment


38

Teaching Activity III (8-10 hrs.)

With the use of project guidelines, information sheets and other aids, teachers assign students a design project (a group project) – Open-day Gift. In

this project, students are going to design and make a capsule toy for batch production. They have to:

� set up a production line to make hundreds of toys

� use a range of manufacturing techniques, tools and machines safely and efficiently

� apply quality assurance system and quality control procedure to the production

� use self-assessment/ peer evaluation to review their progress and record the skills they have learned and rate their level of competence

Teachers can use different themes that are related to school life, such as Sports Day or Swimming Gala, for the design and activity.

Unit Objectives Possible Learning & Teaching


Students should learn to work

successfully as a team to design for

high-volume manufacturing, by

applying the knowledge, skills and

understanding they developed

during the research/ investigative

activities and hands-on/ practical

activities.

� Using project guidelines, information

sheets and other aids, teachers will assign

students with a design project (a group

project), Open-day Gift, in which they:

– design and make a capsule toy

which will be sold or given away

in school open day

– think about how designing for

high-volume manufacturing

brings new considerations and

constraints to a designer/ engineer

– identify roles for their team

members, perhaps setting up a

mini-enterprise to make the

product in volume

Project guidelines,

information sheets and worksheets

Self-assessment and peer evaluation forms

Sample Capsule Toys


If products are made to be sold, then

teachers must ensure that relevant

safety procedures are followed

Teachers need to

– plan a series of short CAD/CAM

projects to develop students’

expertise with different resources

quickly

– develop and make prototypes of

the product, to ensure that it can

– set achievable limits on designs so

that students need only a short


39

be manufactured easily

– make the product efficiently and

ensure high quality using similar

processes to those used

commercially

– they will develop quality

assurance procedures and use

production aids, e.g. jigs, moulds,

templates, CAM, where

appropriate, to improve the quality

of manufacturing

period of machining time, for

example. limit the size, number of

colours that students can be used;

reduce complexity of the design.

In the project, students will:

– refine a single idea from a range

of ideas and draw up a

manufacturing specification

– resolve conflicting demands when

proposing design ideas in the team

– consider whether a product is

marketable, maintainable and

sustainable when generating ideas

– use a range of CAD applications

in an integrated way to help them

generate ideas, where appropriate

– involve students in planning

activities so that they have other

work to do while waiting for the

machines. Ask them to plan ahead

and indicate when they are likely to

need the machine.


40

– produce plans and predict the time

needed for production

– use CAM equipment to

manufacture the product if

necessary

– review whether the product meets

the design specification at

different development stages

– work effectively within a team,

discuss and respond to

information, working on

designing and making aspects, and

review product outcomes

Special needs note:

CAM machines, e.g. plotter/ cutters,

engravers, mills and lathes, can help students

with motor-control difficulties or a lack of

physical strength to make products with a

quality of finish which are usually beyond

their scope. The opportunity to produce

items that are close to the quality of those

sold in shops helps to motivate students. In

addition, students make a number of

products in a short amount of time will give

them more opportunities to succeed. CAD

can help students who have difficulty in

drawing as well.


41

Moreover, students will analyse and record

their progress by:

– using a tick-box checklist for self-

assessment of relevant skills (can

do well/ can do/ need to improve)

– using record sheets to record how

they feel about tasks that they

carry out. Are they easy or

difficult?

– taking part in class or peer-group

discussions, presentations of

projects, displays of work, and

compilation of portfolios to help

them focus on performance

– writing targets for projects and

discuss with them using prompt

questions, e.g.

� What did you do best?

� What do you need to work at?

� What advice and help have you been

given?

� What is the most useful thing that you

have learned?

� In what ways have you improved?

� What will you do differently next time?


42

SECTION 5 – SAMPLE LESSON PLANS

Teaching Unit 2: Incredible Structures and Mechanisms

Time: 40 min. x 2

One period of this lesson will be used for investigation and another period for practical activities.

Learning Objectives / Outcomes

Students should be able to:

� realize what are the lifting mechanism;

� understand how lifting mechanism work and how they are made;

� make labelled drawings to show how the lifting mechanism work; and

� construct simple lifting mechanism.

Learning and Teaching Activities

Introduction – whole class (15 min.)

� Show students examples of simple lifting mechanisms

constructed with construction kits, e.g. toy cranes.

� Discuss with students:

– How does the lifting mechanism work?

– What is the difference between a pulley wheel and a screw

jack?

� Encourage them to learn and use the correct terminology –

crank, screw jack, wheel and axle, etc.

Concepts and Techniques:

- Pulley system

- Winch

- Screw jack

- Hydraulic lift

- Technical drawing

- Assemble techniques

Resources:

- Everyday items with lifting

mechanisms

- Pre-made lifting mechanisms

(use construction kits such as

Lego, Fischertechnik)

- Topic 1.2, 1.3

Investigative Activities – group work (15 min.)

� Allow students time to explore the lifting mechanisms.

Investigative Activities – whole class (15 min.)

� Using a model to demonstrate how to make labelled drawings.

Introduce arrows to show direction of movement.

� Using components of construction kits, e.g. gears and pulleys to

demonstrate how to make working models of simple lifting

mechanisms.

Generic Skills:

- Collaboration skills

- Communication skills

- Creativity

- Critical thinking skills

- Problem-solving skills


43

Practical Activities – individual work (25 min.)

� Students are required to make their own labelled drawings on

the worksheet of the lifting mechanism.

� Students are required to construct a lifting device with

construction kits.

Reinforcement – whole class (10 min.)

� Quiz – to check student’s understanding of the concepts and the

use of construction techniques.

� Students are required to collect winding toys, pictures of cranes

to be displayed in the class

Assessment Opportunities

� Mark the worksheets and check whether students construct the lifting mechanism properly or not.

� Homework: Students are required to collect (shoe) boxes for the next lesson, and pictures showing

products with mechanisms for classroom display.

Notes

� It can be difficult to locate examples of lifting mechanisms. Toy cranes and pulley systems are

found in science laboratory can be used to demonstrate the working components. Other mechanical

devices are much more difficult to find as they tend to be huge, e.g. hoists, so these will need to be

replicated with construction kits beforehand.

� Adequate amount of suitable construction kits should be available.

� Ask the students to focus on the lifting mechanism which is suitable for the construction of “Water

Rocket Launch Platform” (Design Project of Unit 2)

� Observe students who have difficulty in conveying information by drawing.


44

(II) Teaching Unit 3: School Open Day

Lesson

Time: 40 min. x 3

Learning Objectives / Outcomes

Students should be able to:

� Identify CNC machine and CAM systems

� recognise how CNC machine work and how CAD/CAM system are integrated;

� operate CNC machine

� make simple products using CNC machine.

Learning and Teaching Activities

Introduction – whole class (20 min.)

� Show examples of simple products made by CNC machine(s), e.g.

key fob and chessman.

� Describe the operation of the machine, what it does and how it

works (how it is controlled by the computer).

�

Concepts and Techniques:

- CAD software

- CNC machining

- Part programme

- G/M Code

- CAM system

-

Investigative Activities – group work (40 min.)^

� Allow students to explore the machine(s) and observe the

simulation/ tryout/ dummy run of it.


– How many axes of movement are provided by the machine?

– What is used to transfer the cutting tool? (stepper/ servo

motor)

� Explain how CAD and CNC are interfaced to form a CAD/CAM

system.


– Before CAD/CAM system is developed, how people go

through the data manipulation process? (manual data input)

– Given a simple part programme, how does it work to

accomplish a task? Find out the meaning of codes used in the

programme.

Resources#:

- CAD software such as

CorelDraw, proDesktop,

TechSoft

- CAM equipment such as

CNC lathe, laser engraver

- Sample products made by

CNC machines

- Pictures of different CNC

machines

- Topic 3.1, 3.3

-


45

Enquiry Activities – whole class (20 min.)

� Using pictures, to demonstrate different types of CNC machines

� Students are required to name the CNC machines shown, and

identify the products made by them.

� know how to produce the same item when using traditional

method

� Students are required to compare and contrast the advantages and

disadvantages of CAM with traditional manufacturing methods.

Demonstration – whole class (15 min.)

� Demonstrate how to make simple items using CNC machine.

� Explicate the necessary safety precautions.

Practical Activities – individual work (25 min.)*

� Students are required to input their CAD drawings into the CNC

machine(s).

� Students are required to set up the machine according to the

necessary safety requirements.

� Students are required to make the 3-D model of their design using

the machine.

Generic Skills:

- Collaboration skills

- Communication skills

- Critical thinking skills

- IT skills

- Problem-solving skills

Assessment Opportunities

� Mark work pieces and check for correct adoption of cautious working process.

� Students are required to collect sample products made by CNC machines, and analyse them with

reference to the factors of time, cost, quality, etc., in order to exemplify the advantages and

limitation of CAM for class presentation in next lesson.

Notes

� # Since the CAD/CAM equipment used is different among schools; teachers need to plan their

lessons/ activities subject to the availability of resources.

� ^ This part of Unit 3 can link to some topics of Module 1, e.g. Programmable Control Systems. In

such topic, students may have already explored to the basic architecture of a programmable control

system. It would be better to teach the theory of part programme and G/M Code in detail in another

lesson.

� * CAM equipment is usually a limited resource in schools. It takes time to process all students’

design using the equipment. Teachers may need to make proper scheduling on the use of the

equipment beyond normal lessons.

� Teachers should check the feasibility of students’ design in advance.

Prompt students to focus on the item(s) that is appropriate for their “Open-day Gift” (Design and Make

Activity)


46

SECTION 6 – TEACHING NOTES

(I) Design for Manufacturing

Several factors should be considered when designing a product that is suitable for

manufacturing. These factors include life-expectancy, maintenance, and the cost reduction.

(a) Counting the Costs

When a manufacturer comes across a new product the major consideration is how to keep

production costs to a minimum. Some elements will be considered as fixed costs while others

are known as variable costs. They are described as below:

� Fixed costs are those incurred in setting up the production line such as machines, the

tooling and factory’s space.

� Variable costs are likely to be the cost of materials, energy used, wages of the

workforce, insurance and maintenance, etc. The costs of storage, transportation,

packaging and selling need to be taken into account as well.

� The actual cost of the manufacturing of a product in terms of its materials and labour

will vary but usually only represents some 5-10% of the final selling price.

(b) Design for life expectancy

Many examples of early pre-packed/ flat-pack DIY/ ready-to-assemble furniture has design

faults or being poorly manufactured or have used inferior materials and fittings, see Fig. 1.

Thus, they do not last long. However, customers expect a certain minimum time that a

product such as a drawer unit will work and a product that fails before a reasonable time can

be very costly to the manufacturer to repair, or in some cases replace.

Fig. 1


47

The major problem with furniture that has been produced using manufactured broads tends to

centre on the following:

� The chipboard fractures where there are weaknesses in the design.

� The fixtures or fittings such as handles or drawer-runners break.

� The lipping comes away from the edge.

� Certain fittings are missing.

If the product suffers from any of these problems, the customer is unlikely to make a repeat

purchase of the same brand and the brand may then develop a bad reputation of being

unreliable. However, if the product can last for many years, consumers will not need to buy

replacements so often and its demand will fall. The quantity of products which need to be

manufactured will therefore drop and as a result, the selling price may rise. Many products

therefore contain components that likely to fail after a number of years and would be very

expensive to replace. This is called planned obsolescence.

(c) Design for maintenance

Designers have to consider how often a new product will need to be maintained during its

usage, and have to take this into account while developing ideas. They will also have to think

about how easy it will be to undertake the maintenance work. If a component needs cleaning,

adjusting or replacing by the user own self (e.g. replacing a battery), it must be quick and easy

to do. Other maintenances however may need to be done by trained specialists because it

may result in damages if the user tries to do it themselves. Ideally, a product should be

maintenance free, but this is likely to involve the use of higher quality components and finer

tolerances when manufacturing, which will inevitably increase the cost.

(II) Hazards and Risk

(a) Health and safety

When designers and engineers produce new products, they need to ensure that they are safe to

use and are also safe to make.

(i) Safe to use

The designer must ensure that the product conforms to all the relevant safety standards,

including those of other countries in which it may be sold to. Careful consideration must be

given that people might misuse the product, and necessary safety devices and warning labels

need to be included. The designer is responsible for any accidents which may occur as a

result of poor design.


48

(ii) Safe to make

There are four main areas to consider to avoid potential accidents:

� The design of machinery and tools being used in the manufacturing process

� The physical layout of the work area

� The training of the workforce

� The safety devices and procedures

In the manufacturing process, there are regulations and codes of practice that must be

observed. It is also essential to reduce the number of potential hazards – unsafe acts or

conditions – which may occur in the workplace. Accidents are extremely costly in terms of

personal distress, compensation and lost production. The engineer need to be held

responsible for any accidents which occur as a result of poor implementation.

(b) Reducing the risks

Although we cannot avoid accident, we can take steps to beware the likelihood of an accident

to occur, and minimise its impact if it does. Legal requirements, codes of practice for health

and safety and a considerable amount of documented information is available to help guiding

the design of safe products and working environments. Ergonomic studies and

anthropometric data can be used to, for example determine optimum positions for displays

and controls of products and machines. They also describe the most suitable sizes and

arrangements for workspaces and conditions (e.g. the distribution of light; noise; heating and

ventilation).

(c) Risk assessment

When a production process may induce hazardous situations, it is necessary to analyse and

assess each particular risk situation and ensure that adequate precautions are taken to

minimise the potential danger. It is the responsibility of an engineer to assess the risks

involved in each stage of production and justify the level of precautions adopted to a safety

inspector.

(III) Standardised Design

In many industries, a basic standardised design is used to maximise economy of large-scale

production. Components, features, accessories and finishes are then added to the basic design

to produce a range of models to offer customers. In the car industry, for example, the same

chassis might be used as the basis for a family saloon, an estate car and a sports car with a

powerful engine.


49

The techniques of modern mass-production were pioneered by Henry Ford in the USA

between 1908 and 1916. He wanted to make a family car capable to accomodate a large

number of people. Through the use of standardised parts, assembly and sub-assembly lines

and an efficient organisation of labour, Mr. Ford reduced the time to put together his ‘Model

T’ car from 12.5 hours to 2 hours 40 minutes (see Fig. 2). Output and sales rose by over 40

times, and selling prices decreased by 1/3.

Fig. 2 ‘Model T’ car

Henry Ford was the first person to develop a fully integrated manufacturing capability. His

plant for making the first Model T cars in the early years of the 20th century was a moving

assembly line, where coal, iron and rubber went in at one end and cars rolled out at the other.

(IV) Global Manufacture

For many companies increase competitiveness by means reducing costs including overheads,

materials, and labour costs. Selling the same product in many countries means that high profit

scale can be achieved if production is centralised in one country. There are a variety of

solutions that a global company can adopt. They can design in one country and build the

components in a second and assemble them in third country. Alternatively they can adopt a

policy of fully integrated manufacturing.

Many issues are raised by global manufacturing, such as the quality of life of people involved,

employment, environment and economic development of those countries.

(V) Corrosion and Associated Environments

The corrosion or degradation of materials costs millions of dollars every year. To reduce these

looses in a cost-effective manner, a good designer or engineer can have crucial contribution to

the society and the conservation of resources.


50

(a) Corrosion

Corrosion is very rapid in moist environments, and particularly near the sea, and is much

slower in dry regions.

(b) Electrochemical corrosion

All metals have a tendency to corrode because they can release electrons to form anions. The

tendency of a metal to give up its electrons can be found by measuring the voltage generated

when it is connected to a standard electrode in a standard electrolyte. This is known as the

Standard Electrode Potential. A table of these values, the Electrochemical Series, is shown in

Table 1. (You may learn this as well in your Science / Chemistry class.)

Electrode

Potential (V)

Sodium -2.71 Anode

Magnesium -2.37 ^

Aluminum -1.66 ^

Titanium -1.63 ^

Manganese -1.63 ^

Zinc -0.76 ^

Chromium -0.74 ^

Iron -0.44 ^

Cadmium -0.40 ^

Nickel -0.25 ^

Tin -0.14 ^

Lead -0.13 ^

Hydrogen 0.00 - - - -

Copper +0.34 V

Silver +0.80 V

Platinum +1.20 V

Gold +1.50 Cathode

Table 1 Electrochemical Series

When two of these elements are connected together in the presence of an electrolyte, the

element with the greater tendency to lose electrons (higher up the table) becomes the anode

and the other element (lower in the table) becomes the cathode. Thus the element with

position higher up the table, the anode will corrode. There are different conditions under

which an electrochemical cell can lead to corrosion and three of the more common ones are

explained below.


51

(i) Composition Cells

These result from the connection of dissimilar metals. These may be components made from

different metals like copper and iron or simply different phases of the same alloy.

(ii) Stress Cells

These result from the existence of regions of differing atomic stresses within the material.

The most highly stressed regions (with high energy) act as anodes and the less stressed

regions act as cathodes.

(iii) Concentration Cells

These result from differences in composition within the electrolyte. The region of the metal

in contact with high concentration acts as the cathode and the region of metal in contact with

a low concentration acts as the anode. Waterline corrosion is a similar phenomenon. Hence,

the metal above the waterline is exposed to oxygen and is cathodic. The oxygen

concentration decreases as the depth beneath the surface increases producing anodic regions.

As a result, the major corrosion occurs just below the waterline.

(d) Use E.M.F. in Preventing Corrosion

We can prevent electrochemical corrosion by applying an e.m.f. (electromagnetic force) of the

opposite polarity to that generated by the electrochemical cell as shown in the following

figure:

Fig. 4 Impressed e.m.f. protects a pipe

This method guarantees that the object, e.g. a buried pipe, to be protected is the cathode and

will not corrode. The other lead from the power supply is connected to some scrap metal

which becomes the anode and corrodes.


52

(VI) Finishing Processes

It will not only to give protection against corrosion or the environment. Finishing processes

are undertaken for other reasons as well. For example, technical reasons to improve wear

resistance and fatigue strength. To the designers, finishing may associate with the visual

qualities of the product. There are also factors associated with the product used which may be

crucial, like the reflection or adsorption of radiant heat, insulation from heat or electricity,

anti-fouling, water repellent or anti-condensation finishes. Whatever reason that finishing is

required, the process by which it is applied is almost certain to have implications for the

design of a product.

(a) Protecting Against Environmental Damage

There a number of general approaches to minimize corrosion. Probably, the most important is

a careful design to avoid water traps – simply putting a drain hole may prevent the corrosion

from beginning. It is also a good practice to seal gaps and joints which are not continuously

welded. Equally, bringing dissimilar metals into contact, for example by using steel bolts

with aluminum components, should be avoided if possible. If unavoidable, insulating

washers can stop electrochemical cells occurring.

It is also possible to reduce the effect of the environment, for example, by adding corrosion

inhibitors to products. Electrochemical corrosion can be avoided by using a sacrificial anode

which will corrode in preference to the component. The metal highest in the electrochemical

series will be the anode and hence will corrode first. Zinc and magnesium are used to protect

steel pipelines and ships in this way.

(b) Metal finishes

If it is to stop an electrochemical cell forming, the finish must provide a barrier between the

metal and the environment which is providing the electrolyte. The barrier can either be an

oxide of the metal itself or an applied barrier.

(i) Metal Oxides

Some metal oxides adhere very strongly to the base metals. Aluminum oxide on pure

aluminum is a well known example. Once formed, the oxide layer will effectively prevents

further corrosion taking place. If it is scratched or damaged, it will reform almost

immediately – on aluminum in a small fraction of a second. The oxide layer is so thin that is

transparent and therefore does not affect the high polish which aluminum can have. Besides,

the oxide layer is porous which enables it to absorb dyes and take a variety of coloured

finishes.


53

The chromium additions to steel which make it stainless, work in a similar way. Complex

chromium oxides formed on the surface of steel and it provides corrosion resistance.

The oxide which is formed by iron when heated adheres to the surface, although less strong

than chromium oxides. This means that a process like blueing, which is the common

workshop heat treatment technique for finishing steels, provides some corrosion resistance

because of the oxide layer formed. Blueing is carried out by heating steel to around 300°C

and then quench in oil.

The oxides formed by zinc, lead, copper and nickel can also adhere strongly to the base metal

giving good corrosion resistance. The copper oxide formed tends to react with atmospheric

pollutants forming a green layer of sulphates and carbonates.

(ii) Applied Barriers

There is a very large range of materials which are applied to metals in order to form a barrier

to the environment and prevent corrosion. These coatings such as paints can be applied by

brushing, rolling or spraying them onto the surface or by dipping the components into tanks of

the coating material. It is also possible to dip components into plastic powders by fluidizing

the powder with compressed air.

Generally, other metals are applied by electroplating. They can also be sprayed on by using a

special gun which includes a heating system or applied by dipping the components into a

heated tank containing the molten metal. The following notes on some of the more common

possibilities serve to show the range available.

Zinc is commonly associated with the galvanising process, which involves dipping the fluxed

components into a bath of molten zinc (at 450-460°C). Window frames, litter bins, buckets,

railings, nuts, bolts and screws are all finished in this way. If the zinc coating is damaged and

an electrochemical cell established, the zinc will corrode in preference to the steel because it

is higher in the electrochemical series. No corrosion of the underlying steel will occur until

all the zinc is worn out. Zinc is also applied by electroplating and sprayed onto the large

structures before painting.

Tin is most commonly applied to steels during production by passing steel sheet through

molten baths of tin (at 315-320°C) – producing tinplates. Tinplate is used to produce food

cans, and will generally form an effective barrier. It does however react with some acids and

sulphur, which is sometimes added as a preservative, and in these cases, the inside of the can

needs to be lacquered. If the tin layer is damaged at any point and the underlying steel is

exposed, steel will become the anode and will corrode first because tin is below iron in the

electrochemical series.


54

Vitreous enamel is basically a borosilicate glass and is used not only because of the protection

it offers, it is also due to its aesthetic qualities and the hard, durable finish. Different colours

are produced by adding metal oxides to the glass.

Plastic coatings are applied to metal components in a similar way to vitreous enamels. The

components to be coated are heated and dipped into a fluidised bed of plastic powder

suspended in pressurised air. A uniform layer is obtained which fuses onto the component as

a result of the heat the component contains. A variety of plastics are used, for example, PVC

which is low-cost and corrosion resistant and often used for street furniture; polythene which

is low-cost and non-toxic is often being used on domestic equipment; and PTFE is non-stick.

There are many other plastic coatings such as epoxy, nylon and polyesters.

Painting is one of the traditional methods of finishing metals, and its nature has changed with

the development of paint technology. Paint is not only associated with oil based paints now,

it is also associated with modern polymers and resins. A variety of materials are used as the

basis of paints, for example, cellulose which produces a hard, resistant surface; vinyls are

excellent for outdoor use; polyesters are extremely hard and can be buffed to a high gloss

finish.

(c) Wood finishes

One of the major difficulties in using wood in outdoor applications is its ability to absorb

water. This causes the wood to expand and can lead to its degradation. Wood can also

subject to attack by bacteria and fungi if they are able to gain access. Clearly, one approach

to protecting timber is, therefore, to provide a barrier between the wood and its environment.

Another approach is to soak the internal structure of the wood with a preservative.

(i) Applied Barriers

As for metals a range of new, modern paint materials have been developed. Many paints can

now be used on either wood or metal, but it is important that the wood is first sealed. If this is

not done, the paint will tend to be absorbed into the interior of the wood and not provide an

effective barrier. The other aspect which makes wood very different from metal is the

aesthetic quality of the natural wood surface. It is often desirable for this to be left visible and

consequently a range of transparent varnishes and lacquers are now also available.

(ii) Internal Perspectives

It is important to ensure a sustained long-term life of wood, in particular when they are used

as posts to support overhead cables or constructions for harbours and bridges. The most

effective method is pressure treatment which is carried out in large vessels capable of

accommodating timber up to 40 metres long. Once treated the timber can last fifty years in all

weather conditions. It is particularly important to use internal preservatives where there is

likely to be erosion so that the new wood exposed will not be vulnerable to attack.


55

(VII) Manufacturing Considerations

Resourcing large scale production is expensive. The need to make profit requires several

manufacturing considerations in the design of new products. Manufacturing considerations

include:

� existing equipment

� labour costs

� plant layout

� energy requirements

� waste products

� quantity considerations

(a) Existing Equipment

Investing in new equipment and machinery is expensive and companies need to consider the

time it takes to break even the costs of their investment in their evaluation of a product.

Products which can be processed, assembled and packaged using existing equipment, are

more favourable.

(b) Labour Costs

Labour cost is a major cost in most industries and control of this is an important objective of

management.

(c) Plant Layout

Many companies make different products on the same site. Products which require a different

production sequence can be interfered with the production schedules of other products. If a

product promises to be very successful it is often more cost effective and efficient to provide

purpose built premises or production lines.

(d) Energy Requirements

In many production processes energy can be a significant part of the total cost of a product. It

is therefore often included in the direct costs. Some products will have higher demands on

energy than others.

(e) Waste Products

Many manufacturing processes produce waste products which have to be disposed of in an

environmentally acceptable way. Some packaging materials can be recycled. Environmental

regulations prevent companies from polluting water sources and bio-filters have to be


56

installed to clean up the effluent before it can be fed into the public sewage system. The

amount of gases that can be released to the atmosphere is also controlled. Companies may

have to install filters to reduce the number and amount of the emissions.

(f) Quantity Considerations

The quantity of products made will have an influence on the profitability of the product

because generally the more products made the cheaper the costs of materials, equipment and

labour. The costs of producing a quantity of goods has to be compared with the income

expected from the sale of goods at a realistic price. If the profit is small then two

considerations have to be made:

� a modification to the design to reduce material costs and production time

� employ different production systems

Moreover, manufacturers should consider:

� reduce the time for production

� minimise the manufacturing processes

� use machining instead of hand work

� reduce people involved

� better use of equipment

(VIII) Total Quality Management

Total Quality Management (TQM) is a concept that was developed by the Japanese after the

Second World War. The aim was to become the best by going through a process of

continuous improvement. The principle now includes improving quality in management as

well as in production. The four strategies for TQM are:

� Senior managers must be responsible to make sure that quality procedures are

followed.

� Employees at all levels and in all jobs must be trained in quality procedures.

� Quality improvement must be continuous.

� The workforce must participate in quality improvement.

This concept of joint responsibility for quality has dramatically changed the management

style of much of modern industry from a pyramid structure where the employee was told what

to do and management was held responsible for failures, to a flatter structure with fewer

middle management and the employees play an active part in ensuring the quality of a product.

TQM stretches from the design concept to delivery to the customer, and has four main aspects

as follows:

� Design - influenced greatly by appearance and usefulness

� Manufacture - the build quality


57

� Performance - the function must be as intended at the design stage and as expected

by the user

� Customer satisfaction - cost and quality must be in harmony


58

SECTION 7 – TEACHERS’NOTES FOR DESIGN AND MAKE

ACTIVITY

Open-Day Gift

This learning task is a design project which focuses on designing and making of an open-day

gift in the form of a capsule toy (refer to Project Guidelines). All manufacturing techniques

employed in producing the toy are covered in Topic 2.1 of Chapter 2. This project provides

an opportunity for students to apply knowledge in an authentic context. Teachers should

design the details subject to time constraints, students’ abilities, and availability of resources

and facilities.

Under the same theme – School Open Day, students will create more design-and-make

products, such as:

� the promotional materials for the Open Day, e.g. poster, flyer, etc.;

� the decoration materials of the DAT room, e.g. banner, display board, etc.;

� the signposts to guide the visitors; and

� the CAD modelling of the toy and the capsule.

The chart on the next page gives teachers an overview of various consideration of this project.


59

OPEN-DAY GIFT – DESIGN PROJECT

Organisational Chart

Unit 3: School Open Day

Open-day Gift: Design Project

Capsule Toy Vending

Machine (optional

product) - extended group activity

from Topic 1.3

- purchased item

Capsule Toy (main

product) - magnetic memo holder

- cartoon figure

- slot-together toy

- key fob

Capsule (optional

product) - vacuum formed capsule

- folded-up capsule

- re-used capsule

Production Method - CAD/CAM, e.g. laser

cutting

- injection moulding

- vacuum forming

- casting

- jig and fixture

Production Line - role-playing

- teamwork

- costing

- production planning

Quality Assurance and

Quality Control - dimensions

- functions

- wastage

- working procedures

Module 5 (probable

cross-linked module

under the same theme) - promotion materials

- decoration

- signpost

- CAD modelling

Designing Activities

&

Making Activities


60

Probable Products

There are three possible products could be made. Subject to the resources available, teachers

could decide the most feasible one to make in school environment.

� Capsule Toy – a product to be made in school settings.

� Capsule – an optional product which could be produced if resources are available.

� Capsule Toy Vending Machine – an optional product which could be produced if

resources are available.

(I) Capsule Toy – The Main Product

The target visitors of the Open Day will be the primary pupils, their parents and former

students. Therefore, the gift, in the form of a capsule toy (refer to Information Sheet 1), will

be a souvenir from the school or the DAT department. There are three ways to produce the

capsule toy. It could be one of the following items: a magnetic memo holder made by

injection/ insertion moulding; a cartoon figure cast in resin (see Fig. 1); a slot-together toy or

a key fob produced by CAM (see Fig. 2). The above capsule toys are suggested items for

teachers’ reference. Teachers could design their own products and select their methods of

production.

Fig. 1 Cartoon figure cast in resin

Fig. 2a Slot-together toy


61

Fig. 2b Key fob

The project guidelines provided in this resource material are based on the fact that the toy will

be produced by injection/ insertion moulding. As different schools have different facilities,

the suggested production method will depends on the majority rule (refer to Information Sheet

2). Some schools may have better equipment for injection moulding (see Fig. 3), therefore

the quality of the toy produced would be better. However teachers and their students have to

prepare a more complicated steel split-mould (see Fig. 4) before using the manufacturing

equipment. It is unlikely to manufacture the product in quantity, because it is not cost-

effective to spend too much time and money to make the mould.

Fig. 3 Manual-operated injection moulding equipment

Fig. 4 Steel split-mould for injection moulding


62

(II) Capsule – The Optional Product

The capsules could be produced by vacuum forming or other methods suggested on the

Information Sheet 3. However, this is only for reference. Teachers could make their own

selection and ways of production. Students could also reuse the capsules from toy stores or

collect empty capsules from schoolmates.

(III) Capsule Toy Vending Machine – The Optional Product

This is an extended group activity which is derived from a question in the quiz of this module.

Students will find out how the mechanism works inside the “black box”. Based on the

findings, students could design and make their own vending machines. Students could also

purchase a half-sized toy vending machine as an alternative to serve the purpose.

Production Line Simulation

To simulate the production line in actual industrial practice, students are encouraged to

experience how different parts of the industry are worked together by role-playing. Please

refer to Information Sheet 3. There are three key components:

� Production planning – e.g. setting up of work schedule

� Production method – e.g. using CAD/CAM equipment

� Quality assurance and quality control – e.g. ensure practicability of the working

procedures and the quality of the final products

If resources are available, two production lines could be set up in this activity. For example,

with 20 students in a DAT class, two production lines, one for the capsule toy and one for the

capsule, could be set up. Since the products are going to be manufactured in quantity,

students’ initial designs will be undergone a selection process. Only chosen ones will be put

into the production lines. The selection process could be conducted within the team or the

class.

Mini-enterprise Activity

The Open Day is a carnival for visitors. Students should be aware of the costing of the project,

including manpower and expenditure spent on the vending machines, promotion materials,

toys and capsules, i.e. fixed costs and variable costs.

At the end of each day, students have to conduct a review on their business and make

adjustment on the price and quantity of supply.

This enterprise activity is designed to develop students’ enterprise skills and attributes that are

important within and beyond the school environment. The following is a list of some

enterprise skills and attributes that have been identified by the curriculum:


63

� Identifying, creating, assessing and taking advantage of opportunities

� Using initiative

� Gathering and managing resources

� Matching personal strengths and weaknesses to undertakings

� Being flexible and dealing with changes

� Monitoring and evaluating personal and others’ performance

� Interpersonal communication and influencing skills

Teachers will take into account that each stage of the technological process of designing,

making and appraising product(s) provides opportunities for students to be enterprising. At

the “designing” stage, students are encouraged to come up with new ideas and innovations,

investigate related issues and develop prototypes; at the “making” stage they are to undertake

materials and production planning; and finally at the “appraising” stage they will reflect on

and evaluate the product and processes.

*The assessment for this design and make activity will be discussed in next topic.


64

SECTION 8 – TEACHING NOTES FOR ASSESSMENT TASKS

Assessment is one of the essential elements in learning and teaching. Teachers are encouraged

to design different assessment tasks to meet the learning objectives.

Assessment Rubrics for Theme-Based Learning Tasks

Rubrics provide specific feedback to the students. Teachers and students, may use rubrics to

assess the learning process and evaluate students’ performance. Students, who best know their

own strengths and weaknesses, are often the best judge for their own performance, Rubrics

reflect what they have done well and where they need to improve. This type of rubric rates the

level of performance of students when aiming towards a high standard of achievement.

Example 1

Focus of Assessment: Teamwork Student Name: _____________________

Names of Partners:__________________

Peer Assessors:_____________________

Criteria Self Peer Teacher

1. I performed my assigned role. Yes / No Yes / No Yes / No

2. I stayed on task. Yes / No Yes / No Yes / No

3. I did my fair share of work. Yes / No Yes / No Yes / No

4. I listened to others’ ideas. Yes / No Yes / No Yes / No

5. I helped the group to solve

problems.

Yes / No Yes / No Yes / No

6. I completed my work on time. Yes / No Yes / No Yes / No

Example 2

Focus of Assessment: Making a Gift Student Names: _________________

Peer Assessors:__________________

Criteria Group Peer Teacher

1. We developed a plan for production. 012345 012345 012345

2. We aimed our product to a target group. 012345 012345 012345

3. We made our product function well. 012345 012345 012345

4. We made our product attractive. 012345 012345 012345

5. We made our product easy to use. 012345 012345 012345

6. We made our product safe to use. 012345 012345 012345

* Performance descriptors: 0 is incomplete; 3 is a good effort; 5 is an outstanding effort.


65

Assessment criteria for Design and Make Activity – Open Day Gift

Each student is required to submit a portfolio accompany with the product designed in design

projects. The portfolio should include all investigatory work, the final working drawings,

evaluation and suggested modifications. The following assessment criteria aim to provide a

guideline to reflect student’s performance at various levels.

Students will be assessed through design project under the following six assessment

categories:

� Identification of needs or opportunities leading to a design brief

� Research into design brief and prepare design specifications

� Generation of design solutions

� Product development

� Product planning and realisation

� Evaluation and testing

(a) Identification of a need or an opportunity leading to a design brief

� provide a detailed description of the situation using various means of communication,

e.g. text, drawings, graphs, photographs;

� identify users and the market

� write a design brief

(b) Research into design brief and prepare design specifications

� examine the purpose of the product;

� identify and collect data relevant to the product and its users

� investigate how existing products meet the needs of requirements

� write a design specification

(c) Generation of design solutions

� generate possible design solutions;

� evaluate their design solutions against the specifications;

� consider whether their ideas meet the needs and beset-fit for the purpose;

� identify the final design proposal for product development; and

� present design solutions using a combination of text, graphics, computer generated

images and 2-D and/or 3-D models.


66

(d) Product development

� make reasoned decisions about: materials, production methods and standard

components based on the investigation results

� ensure the product meets the design specifications by testing and modelling

� consider the possibilities and implications for quantity manufacture when developing

the prototype

� modify the final design proposal if necessary

� prepare details about the final solution

� present the final solution using a combination of text, graphics and computer images.

(e) Product planning and realisation

� produce an action plan to arrange different tasks

� complete a quality outcome suitable for the target user(s);

� ensure that the outcome functions effectively;

� use tools and equipment accurately, safely and effectively;

� be prepared to adjust working procedures in response to changing circumstances;

� use a range of skills and techniques appropriate to the task; and

� prepare the materials economically

(f) Evaluation and testing

� evaluate the outcome against its purpose and its original need, e.g. checking against

original specification;

� review whether they use the resources appropriately, e.g. time, materials, equipment

and production methods;

� carry out tests to reach conclusions that suggest necessary modifications/

improvements, e.g. questionnaire

� analyse the performance of the planned quality control system in the manufacture of

the prototype.


67

Design Projects

When using a ladder to carry out maintenance work for a house, there can have problems in

handling tools and equipment while keeping one’s balance and safety. Students are required

to design and make a device which can be attached firmly to the ladder to store/support a

variety of items to be used.

The assessment criteria for design project 1 is described as follows.

(a) Identification of a need leading to design brief

� Analysis different kinds of ladders, tools, equipment and materials using for

household maintenance works

� Consider users’ needs

� Identify the specifications of the problem

(b) Research into design brief resulting in a specification

� Identify possible features of a product that can store and support the items safely.

� Different designs of carriers for maintenance equipment are investigated.

� Design specifications and requirements of the product are listed

(c) Generation of design solutions

� A collection of annotated sketches showing a range of appropriate solutions.

� 2- and/or 3-D models are made to facilitate product development.

� The proposed ideas are evaluated against the specification and advantage and

disadvantage are identified.

� The best ideas are chosen after consideration of need satisfaction and fitness to the

purpose.

� The final design proposal is presented using a combination of text, graphics and

computer generated images.

(d) Product development

� Consider possible choice of materials based on investigation and testing.

� Suitable construction methods as well as available standard components are

considered through investigation and testing.

� The possibilities and implications for quantity manufacture are considered and

recorded.

� The details of materials, production methods and standard components required are

recorded using a combination of text, graphics and computer images.


68

(e) Product planning and realisation

� An action plan is produced to specify the sequence for the manufacturing with

reference to materials, tools and equipment being used.

� Making/ fabrication is carried out to demonstrate the economical and efficient use of

materials, tools and equipment. Modifications will be made during production

process in response to changes.

� Safe working procedures.

� Appropriate choice of skills and techniques are used to produce quality products.

(f) Evaluation and testing

� The outcome is evaluated against the original specification.

� Its fitness for purpose is tested on the target user group.

� Proposals for further development are suggested with illustrations to show where

improvements could be made.

For project 2 and 3, teachers may formulate the assessment criteria accordingly.


69

Exercise for Structures and Mechanisms

For question1 and 2, students are expected to provide examples for each product / structure in

our daily lives.

2 (a) total gear ratio = 6;

(b) MA = 4.8

4 (a) VR = 120;

(b) efficiency = 13%

5 (a) 40;

(b) 2 ms-1

;

(c) 1885 W;

(d) 1320 W;

(e) 630 N


70

QUIZ

Multiple Choice Questions

Each question carries [2] marks.

1. C

2. B

3. B

4. A

5. D

Long Questions

1. [1] mark is given for each reasonable answer [3 marks max.] for appropriate explanations.

� Injection moulding is a manufacturing process where heated plastic is forced into a

mould cavity under pressure.

� The cavity is filled with plastic, and the plastic will solidify

� Injection moulding is suitable for mass production.

� The moulding tools must be made to high levels of precision and must be robust

enough to withstand the moulding process.

2. [3] marks are given for the diagram with correct labels and [1] mark is given for each

reasonable answer, a maximum of [ 8 ]marks will be given for appropriate explanation.

� Drawing of stress / strain graph with labels for elastic region, yield stress, plastic

region and ultimate stress.

� Stress is the force per unit area acting on a body or system.

� Young’s modulus = stress / strain

� The stress / strain graph for a material shows how it responds to tensile, compressive

or bending forces placed upon it.

� Tensile forces are important in relation to design contexts with pulling forces, e.g.

cables.

� Compressive forces are important in relation to design contexts with pushing forces,

e.g. columns.

� Bending forces are important in relation to design contexts where stiffness matters,

e.g. beams.


71

3. (a) [1] for correct name of t material.

(b) [1] for each reasonable answer [2 max]

(c) [1] for correct choice of manufacturing process and [1] for each reasonable

description for the process. [5 max]

4. (a) The normal maximum load for the lift = 80 kg x 10 persons = 800 kg. [1]

(b) Factor of Safety = Design Load / Normal Max. Load;

3 = Design Load / 800 kg;

Hence, Design Load = 2400 kg. [2 max]

(c) A maximum of 3 marks given for reasonable answers. [3 max]

- Structures are designed to carry higher loads than those they are normally

expected to support. The factor of safety ensures that passengers are safe even

if the lift is overloaded.

(d) A maximum of 2 marks is given for reasonable answers. [2 max]

- Painting, plastic coating or addition of chromium to make it stainless

- To produce a corrosion-free, non-tarnishing, smooth, nice-looking surface

(e) The glass will not scattered into pieces on impact. [2 max]

(f) sight- seeing or safety reasons [2 max]


72

SECTION 9 – REFERENCES

Reference Books

Buzan, T. & Buzan, B. (1996). The Mind Map Book. Penguin Group.

Caborn, C. & Mould, I. (2000). Design & Technology. Thomas Nelson & Sons.

Cave, J. (2004). Access Technology: Designing. Nelson.

Cosway, T., & Fasciato, M. (1998). Design & Make It: Resistant Materials. Stanley Thornes.

DATA. (1999). Developing Through Design & Technology. The D&T Association.

Eggleston, J. (2001). Teaching Design & Technology. Open University Press.

Green, W. S. & Jordan, P. W. (1999). Human Factors in Product Design. Taylor & Francis.

Heller S. & Drennan, H. (1997). The Digital Designer. Watson-Guptill.

Kimbell, R. (1997). Assessing Technology. Open University Press.

Kimbell, R. & Stables, K. (1996). Understanding Practice in Design & Technology. Open

University Press.

Lee, R. & Aldridge, J. (1991). Design Briefs: A Complete Introduction to CDT. Cambridge

University.

Loewy, R. (2007). Industrial Design. Penguin.

Morrison, J. et al. (1993). Design Capability & Awareness. Longman

Norman, D. A. (2002). The Design of Everyday Things. Basic Books.

Norman et al. (2000). Advanced Design & Technology. Longman.

Nuffield Foundation. (1996). Nuffield Design & Technology: Product Design. Longman.

Royal College of Art Schools Technology Project. (2000). Advanced Manufacturing Design

& Technology.Hodder Murray.

Sellwood & Hutchinson. (1996). Design & Problem Solving. Thomson Learning.

Shepard, T. & Loft, A. (1998). Design & Make It: Graphic Products. Stanley Thornes.

Sparke, P. & Stone, A. (1997). The New Design Source Book. Knickerbocker Press.


73

Learning Objectives of Design Implementation and Material Processing

Module 3 Design Implementation and Material Processing (Extracted from the Design

and Applied Technology Curriculum and Assessment Guide (S4-6))

This module enables students to explore the conversion of some readily available materials

and components into final products. It focuses on the implementation of design and material

processing, and on how computer-aided manufacturing (CAM) is used in production.

Topics

Students should

learn

Outcomes

Students should be

able to

Explanatory notes

Materials,

components and

systems

• Properties and

choice of

materials

• Materials and

structures

• Mechanisms

• New materials

1. Understand that

properties and

working

characteristics

influence the choice

of materials and

components

2. Understand the

strength of material

and design

appropriate

structures in a

system

3. Apply mechanisms

for control systems

4. Understand the use

of new materials

• Explore various materials for particular

applications in design, fabrication and control

(e.g. classification, working properties,

quality, selection and testing, and standard

components)

• Explore how the choice of materials affects a

design

• Apply the concept of strength and stiffness of

structure in design (e.g. safety factors, simple

calculations: Young’s modulus of a material,

loads experienced by the members of a

structure in equilibrium, and bending moment

and shear force diagrams of simply supported

beams and cantilevers)

• Apply simple calculations to determine the

mechanical advantage (M.A.), velocity ratio

(V.R.), efficiency and torque of a mechanical

system

• Study the use of modern and smart materials

(e.g. solar panels, thermo-ceramics, liquid

crystal displays (LCD), carbon fibres and

nano-materials, and shape memory alloys) in

industry through research and exploration

Processing and

manufacturing

• Manufacturing

processes and

techniques

• Scale of

production

• Quality assurance

and quality

control

5. Select, explain and

execute appropriate

manufacturing

processes and

techniques

6. Explain when it is

most appropriate to

use different scales

of production

7. Consider the

application of

• Suggest appropriate manufacturing processes

for production (e.g. manual or automated, jig

and fixture, tools, machinery and equipment,

fabrication processes, forming and moulding,

and finishing processes)

• Deduce from production analysis how and

why products are manufactured (e.g. using

one off / batch / mass production)

• Study, as in a case, a structured management

process for quality manufacturing (e.g. quality

assurance, quality control, accuracy and


74

Topics

Students should

learn

Outcomes

Students should be

able to

Explanatory notes

quality control in

production

tolerances, and quality standards in

production)

CAM

• Computer

numerical control

(CNC) and CAM

• Basic concepts of

Computer

Integrated

Manufacturing

(CIM) and

Flexible

Manufacturing

System (FMS)

• The impact of

CAM on

manufacturing

8. Understand the use

of CNC machines

and CAM systems

in industry

9. Understand CIM

and FMS, and their

wider application in

industry

• Discuss the advantages and limitation of some

commonly-used computer numerically

controlled machines and computer-controlled

tools (e.g. laser cutter, lathe, milling machine,

and engraver)

• Explain how CAD and CNC can be interfaced

to form a CAD/CAM system

• Explain the impact of CAD/CAM on

manufacturing (e.g. Just-in-time (JIT), mass

customisation, production logistics), and

compare and contrast the advantages and

disadvantages of CAM with traditional

manufacturing methods (e.g. time, costs,

waste management, standardisation and

reliability)


75

SECTION 10 – ACKNOWLEDGEMENTS

The authors wish to thank the following persons/organizations for permission to use their

photographs and images:

Under the GNU Free Documentation License:

- P. 49 authors wish to thank the following persons/organizations for permission to use their

photographs and images:

Every effort has been made to trace the copyright for the photographs and images as needed.

We apologize for any accidental infringement and shall be pleased to come to a suitable

arrangement with the rightful owner if such accidental infringement occurs.


76



Education Bureau

The Government of the HKSAR

Developed by

Institute of Professional Education

And Knowledge (PEAK)

Vocational Training Council

Design and Applied Technology (Secondary 4 - 6) · Design and Applied Technology (Secondary 4 - 6)...

Documents

Transcript of Design and Applied Technology (Secondary 4 - 6) · Design and Applied Technology (Secondary 4 - 6)...