Links & Linkages

Applications in Design & Engineering: Compound Machines Curriculum Packet

1

v2.0

Overview:In this lesson, students will learn how different types of linkages can be used to redirect or convert motion. Students will build a series of mechanisms and then work as a team to create a custom design that includes a linkage.

Click here to explore the entire Kid Spark Curriculum Library.

Learning Objectives & NGSS Alignment: Identify different types of links/linkages. Build and analyze a series of linkages. Use Kid Spark engineering materials to create a custom design.

Scientific/Engineering Practice - Developing and using models Crosscutting Concept - Systems and system models

Convergent Learning Activity:1. What is a Linkage? A linkage is an assembly of links connected by joints or pivots. Linkages can be used to change the direction of motion, convert motion, or to create mechanical advantage to make work easier.

Linkages can be any size or shape. Pictured below are a few examples of straight links and geometric shaped links that can be made using Kid Spark engineering materials.

Activity Time: 120 Minutes

Targeted Grade Level: 6 - 8

Student Grouping: Teams of up to 4 students

Additional Lesson Materials: - Teacher Lesson Plan- Student Engineering Workbook

Kid Spark Mobile STEM Lab: Young Engineers OREngineering Pathways

LinkLink

Joint

Straight Links Geometric Shaped Links

2

2. Creating Different Types of Linkages Instructions: Build and test at least two of the linkages shown below.

Lever A lever is one of the most basic types of linkages and mechanisms. A lever consists of a lever arm (link) and a fulcrum (joint). Levers can be used to change the direction of motion or to create mechanical advantage. Mechanism and machines that create mechanical advantage are extremely useful because they reduce the amount of effort needed to move or raise something. To increase the mechanical advantage in a lever, simply move the fulcrum closer to the load.

Build Instructions: Page 3

Reverse Motion Linkage In a reverse motion linkage, as one end of the linkage is pulled or pushed, the other end of the linkage reacts in an opposite direction. This linkage is comprised of five straight links, connected by four axle joints. The linkage is connected to a center support structure which guides its movement.

Build Instructions: Pages 4 - 5

Parallel Motion Linkage In a parallel motion linkage, as one end of the linkage is pulled or pushed, the other end of the linkage reacts in the same direction. This linkage is comprised of three straight links, connected by two axle joints. The linkage is connected to a support structure which guides its movement.

Build Instructions: Pages 6 - 7

90° Bell Crank Linkage The bell crank linkage transmits motion 90° by pivoting around a center fixed point. This linkage is comprised of three links that are connected by two axle joints. The linkage is connected to a support structure which guides its movement.

Build Instructions: Pages 8 - 9

Lever Arm (Link)

Fulcrum (Joint)

Effort

Load

3

LeverFollow the step-by-step instructions to assemble a lever.

1 2

1x Beams

4x Blocks

2x Half Beams

1x Single Snap Block

1x Hinge Block

3

1x Beams

2x Blocks

1x Snap-In Wheel

Lever Arm (Link)

Fulcrum (Joint)

Effort

Load

Instructions: Press down on one end of the lever and observe how the other end raises in the opposite direction. Try movingthe fulcrum closer to the load and observe how less effort isrequired to raise the load.

4

Reverse Motion LinkageFollow the step-by-step instructions to assemble the reverse motion linkage.

1 2

2x Beams

4x Blocks

3 4

3x Half Beams

1x Risers

4x Blocks

2x Single Snap Block

3x Axle Block

2x Double Snap Block

4x Single Snap Block

5

Reverse Motion LinkageFollow the step-by-step instructions to assemble the reverse motion linkage.

5 6

7

2x Block

1x Half Beam

2x Axle Block

1x Single Snap Block

4x Blocks

2x Beam

Instructions: Pull or push one end of the linkage and observe how the other end moves in the opposite direction.

6

Parallel Motion LinkageFollow the step-by-step instructions to assemble the parallel motion linkage.

1 2

2x Beams

4x Blocks

3 4

2x Half Beams

6x Blocks

2x Axle Block

2x Axle Block

4x Risers

2x Half Beams

2x Half Beams

2x Single Snap Block

7

Parallel Motion LinkageFollow the step-by-step instructions to assemble the parallel motion linkage.

5

4x Block

6

1x Half Beams

2x Axle Block

2x Single Snap Block

Instructions: Pull or push one end of the linkage and observe how the other end moves in the same direction.

8

90° Bell Crank LinkageFollow the step-by-step instructions to assemble the 90˚ bell crank linkage.

1 2

2x Beams

4x Blocks

3 4

3x Half Beams

2x Risers

1x Blocks

2x Single Snap Block

3x Axle Block

2x Double Snap Block

4x Single Snap Block

2x Axle Block

1x Mini Curved Beam

1x Risers

9

90° Bell Crank LinkageFollow the step-by-step instructions to assemble the 90˚ bell crank linkage.

5

8x Block

2x Beams

Instructions: Pull or push one end of the linkage and observe how the linkage transmits motion 90° by pivoting aroundthe center fixed point.

10

Divergent Learning Activity:

Scenario: Kid Spark Engineering is currently accepting proposals for new and creative product inventions or innovations that serve a specific purpose.

Design & Engineering Challenge: Develop a new product or design that includes some type of linkage. See example below.

Specifications/Criteria: 1. Students will work in teams of up to 4 to design and engineer a new product or design that serves a specific purpose. Teams can invent something completely new or improve an already existing product.

2. Teams must work through each step of the design & engineering process to design, prototype, and refine their design. Teams will demonstrate and present their designs to the class when they are finished.

3. The product or design should include some type linkage that enables it to function correctly.

4. Teams must determine the overall dimensions (length, depth, and height) of the product or design, as well as any detailed specifications that are relevant to the design.

5. With each building component costing $2, determine the total cost of the design.

Example Idea:

Product Innovation/Invention: Extendable Gripper

Purpose: Retrieve things safely from a distance

Design Notes: The extendable gripper is a linkage comprised of six links and seven joints (axle blocks). To extend the gripper, push handles together. To retract, pull handles apart. The gripper has a maximum extension of 50 cm.

Dimensions: 22 cm x 12 cm x 6 cm (L x D x H)

Material Cost: 29 components x $2 = $58

Length - 22 cm

Height - 6 cm

Depth - 12 cm

Max Extension - 50 cm

Handle

Handle

11

Challenge EvaluationWhen teams have completed the design & engineering challenge, it should be presented to the teacher and classmates for evaluation. Teams will be graded on the following criteria:

Design and Engineering Process: Did the team complete each step of the design and engineering process?

Design Specification: Did the team complete the design specification?

Team Collaboration: How well did the team work together? Can each student describe how they contributed?

Design Quality/Aesthetics: Is the design of high quality? Is it structurally strong, attractive, and well proportioned?

Presentation: How well did the team communicate/explain all aspects of the design to others?

Design Specification

Team Collaboration

Design Quality/Aesthetics

Complete/well-detailed and of high quality

Every member of theteam contributed

Great design/greataesthetics

Most members of theteam contributed

Good design/goodaesthetics

Average design/average aesthetics

Poor design/pooraesthetics

Few members of the team contributed

Team did not work together

Presentation

Points

Total Points

Proficient4 Points

Advanced5 Points

Partially Proficient3 Points

Not Proficient0 Points

/25

Grading Rubric

Complete/opportunities for improvement

Incomplete/opportunities for improvement Incomplete

Great presentation/very well explained

Good presentation/well explained

Poor presentation/poor explanation

No presentation/no explanation

Design & Engineering Process

Completed all 5 steps of the process

Completed 4 steps of the process

Completed 3 steps of the process

Completed 2 or fewer steps of the process

12

Building BasicsThe following tips will be helpful when using Kid Spark engineering materials.

Connecting/Separating ROK Blocks:

ROK Blocks use a friction-fit, pyramid and opening system to connect. Simply press pyramids into openings to connect. To separate blocks, pull apart.

Connecting/Disconnect Smaller Engineering Materials:

Smaller engineering materials use a tab and opening system to connect. Angle one tab into the opening, and then snap into place. To disconnect, insert key into the engineered slot and twist.

Snapping Across Openings:

Materials can be snapped directly into openings or across openings to provide structural support to a design. This will also allow certain designs to function correctly.

Attaching String:

In some instances, string may be needed in a design. Lay string across the opening and snap any component with tabs or pyramids into that opening. Be sure that the tabs are perpendicular to the string to create a tight fit.

2cm18cm

9 Openings

Measuring:

The outside dimensions of a basic connector block are 2 cm on each edge. This means the length, depth, and height are each 2 cm. To determine the size of a project or build in centimeters, simply count the number of openings and multiply by two. Repeat this process for length, depth, and height.

2cm

2cm

4cm 4cm

4cm

55-02148-200