Chapter 1 Introduction to Automation Technology

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1.0 Introduction to Automation TechnologyOUTLINE:1.1 Automation in production systems1.2 Type of manufacturing systems automation1.3 Basic elements of an automated system1.4 Advanced automated function1.5 Levels of Automation1.6 Reason for automated and not automated1.7 Social and Safety issues of industrial automationOBJECTIVES:1. To explain the definition of industrial automation2. To distinguish the fixed, programmable and flexible automation3. To classify the element of automation function and level4. To define the reason of automation, social and safety issues in

automation

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• Automation and robots are two closely related technologies. Both are connected with the use and control of production operations. Automation is a technology dealing with the application of mechatronics and computers for production of goods and services.

• The automated elements of the production system can be separated into two categories:

Automation of the manufacturing systems in the factoryComputerization of the manufacturing support systems

• In modern manufacturing systems, the two categories overlap to some extent, because the automated manufacturing system operating on the factory floor are often implemented by computer systems and connected to the computerized manufacturing support system and management information system operating plant and enterprise level.

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1.1 AUTOMATION IN PRODUCTION SYSTEMS

Cell or system level

Machine level

Device level

Plant level

Enterprise level

Level of automation

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1.1.1 Automated Manufacturing System

• In an industrial context, we can define automation as a technology that is concerned with the use of mechanical, electrical /electronic and computer based system to control production process.

Example of this technology include : transfer lines that perform a series of machining operation mechanical assembly machines feedback control systems numerically controlled machine tools logistic support tools automated inspection system for quality control automated material handling system and storage system to integrate

manufacturing operation CAD/CAM system and robots- robots are mechatronic devices that

assist industrial automation.


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1.1.2 Computerized Manufacturing Support Systems

• Automation of the manufacturing support systems is aimed at reducing the amount of manual and clerical effort in product design, manufacturing planning and control and the business functions of the firm.

• Computer technology is used to implement automation of the manufacturing systems in the factory.

CIM (computer integrated manufacturing) denotes the pervasive use of computer system to design the products, plan the production, control the operations, and perform the various business-related functions in one system that operates throughout the enterprise.

CAD denotes the use of computer systems to support the product design function.

CAM denotes the use of computer systems to perform function related to manufacturing engineering such as process planning and numerical control part programming.

CAD/CAM is used to indicate the integration of two into one systemENT471 Automation


1.2 Type of Automated Manufacturing Systems

1.2.1 Fixed Automation

• Fixed Automation is a system in which the sequence of processing or assembly is fixed by physical equipment configuration. The operation are usually simple, it used with high demand rates and inflexible product design.

• Fixed Automation is used when:• The volume of production is very high (high production rates)• It is therefore appropriate to design specialized equipment to process

products at high production rates and low cost (custom-engineered with special purpose equipment to automate a fixed sequence of operation.

• Relatively inflexible in accommodating product variety

Flexible

Automation

Programmable

Automation

Fixed

Automation

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• A good example of fixed automation can be found in the automobile industry, where highly integrated transfer lines are used to perform machining operation on engine and transmission component.

• The economics of fixed automation is such that the cost of the special equipment can be divided over a large number of units produced, so that the resulting units cost can be lower relative to alternative method of production.

• The risk encountered with fixed automation is that the initial investment cost is high and if the volume of production turns out to lower than anticipated, then the unit costs become greater.

• Another problem with fixed automation is that the equipment is specially designed to produce only one product and after that product’s life cycle is finished, the equipment is likely to become obsolete. Therefore, for products with short life cycles, fixed automation is not economical

1.2 Type of Automated Manufacturing Systems

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1.2.2 Programmable Automation

• Programmable Automation is a system which the production equipment is designed with capability to change the sequence of operations to accommodate different product configurations.

• The operation sequence is controlled by a program which is a set of instructions coded so that they can be read and interpreted by the system. New programs can be prepared and entered into the equipment to produce new products.

• The physical setup of the machine must also be changed, tools must be loaded. Fixtures must be attached to the machine table and the required machine setting must be entered. This change over procedure takes time.

• Programmable Automation is used when:1. The volume of production is relatively low than fixed automation. There is

a variety of products to be made, part typically made in batches. 2. In this case, the production equipment is designed to be adaptable to

variations in a product configuration.3. High investment in general purpose equipment

Introduction to Automation Technology

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• This adaptability feature is accomplished by operating the equipment under the control of a “program” of instructions that has been prepared especially for a given product.

• The program is read into the production equipment and the equipment performs that particular sequence of operations to make that product.

• In terms of economics, the cost of the programmable equipment can be spread over a large number of products even though the products are different. Because of the programming feature and the resulting adaptability of the equipment, may different and unique products can be processed economically in small batches (batches production and medium volume).

Example : SMT production line in PCBA manufacturingSMT – Surface Mount TechnologyPCBA – Printed Circuit Board Assembly


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Flexible Automation

• Flexible Automation is an extension of programmable automation. It is a system capable of producing a variety of products with virtually no time lost due to the change over from one product to next or one part style to the next.

• There is no lost production time while reprogramming the system and altering the physical combination and schedules of parts or products instead of requiring that they be made in batches.

• It is designed to manufacture a variety of product or parts with low production rates, varying product design and demand.

• The features of flexible automation1. High investment for custom-engineered system2. Continuous production of variable mixtures of products and medium

production rates3. Flexibility to deal with product design variation


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• This type of automation is most suitable for the mid-volume production range. Flexible automation possesses some of the features of both fixed and programmable automation. Other terms used for flexible automation include Flexible Manufacturing Systems (FMS) and Computer Integrated Manufacturing (CIM).

• Flexible automation typically consists of a series of workstations that are interconnected by material-handling and storage equipment to process different product configurations at the same time on the same manufacturing system.

• A central computer is used to control the various activities that occur in the system, routing the various parts to the appropriate stations and controlling the programmed operations at the different stations.

• One of the features that distinguish programmable automation from flexible automation is that with programmable automation the products are made in batches. When one batch is completed, the equipment is reprogrammed to process the next batch. (Flex. Auto can produce one of a kind, batches not required)


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• With flexible automation, different products can be made at the same time on the same system. This feature allows a level of versatility that is not available in pure programmable automation.

• This means that products can be produced on a flexible system in batches, if desirable, or that several products can mix on the same system. The computational power of the control computer is what makes this versatility possible.

• Flexible Automation advantages: 1. Increased speed and productivity. 2. Reduced manual labor. 3. Improved consistency. 4. Greater reliability. 5. Greater accuracy and consistency. 6.Reduced cost of assembly

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Three types of automation relative to production quantity and product variety

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Introduction to Automation TechnologyProduction volume of different type of automation

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Introduction to Automation TechnologyBASIC ELEMENTS OF AN AUTOMATED SYSTEM

1) Power to accomplish the automated process2) Program Instruction3) Control System

1. Power to accomplish the automated process• An automated system is used to operate some process and power is required to

drive the process as well as the controls.

• The principal source of power is electricity: Available at moderate cost. Can be readily converted to alternative energy forms (mechanical, thermal,

light, acoustic, hydraulic and pneumatic). Low level power can be used to accomplish functions such as signal

transmission, information processing and data storage and communication. Can be stored in long-life batteries for use in locations where an external

source of electrical power is not available.

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Manufacturing process and their power requirements

PROCESS POWER FORM ACTION ACCOMPLISHED

Casting Thermal Melting of metal

EDM Electrical Metal removal

Forging Mechanical Metal work part deformation

a) Power for the ProcessThe term ‘process’ refers to the manufacturing operation that is performed on work unit as follows:Material handling functions: Loading and unloading the work unit

Material transport between operations

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b) Power for Automation• Controller unit:Need electrical power to read the program of instructions,

calculations and execute the instructions by transmitting the proper commands to actuating devices.

• Power to actuate the control signals:Controller sent the commands by means of low-voltage control signal to provide the proper power level for actuating device (motor).

• Data acquisition and information processing: Keeping the records of process performance or product quality.


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2) Program of instructions

The action performed by an automated process are defined a program of instructions whether the manufacturing operation involves low, medium or high production.

• Work cycle programs The simplest automated processes, 1 step. The more complicated systems

consist of multiple steps. The process parameter changes in each step

• Decision making in the Programmed Work Cycle Each work cycle consists of the same steps and associated process changes

with no variation from one cycle to the next. Operator interaction Different part or product styles are processed by the

systemVariations in the starting work unit.

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3) Control system

• Closed loop control system Known as feedback control system, the output variable is compared with an

input parameter and any difference between the two is used to drive the output into agreement with the output.

• Open loop control system Operates without the feedback loop. The controls operate without measuring the

output variable, so no comparison is made between the actual value of the output and the desired input parameter.

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Introduction to Automation Technology1.4 ADVANCED AUTOMATED FUNCTION

Safety monitoring• An automated system is often installed to perform a potentially dangerous

operation that would otherwise be accomplished manually by human workers.

• To protect human workers in the vicinity of the system

• To protect the equipment associated with the system

Example: Limit switches, photoelectric sensors, temperature sensors, heat or smoke detectors, pressure-sensitive floor pads and machine vision systems.

Maintenance and repair diagnosticsStatus monitoring: To monitor and record the status of key sensors and parameter

of the system during normal operation.

• Failure diagnostics: The failure diagnostics mode is invoked when a malfunction or failure occurs.

• Recommendation of repair procedure: The subsystem provides a recommendation procedure to the repair crew as to the steps that should be taken to effects repairs. ENT471 Automation


Error detection and recovery• Error detection: Used the automated system’s available sensor system to

determine when a deviation or malfunction has occurred, correctly interpret the sensor signal and classify the error.

• Error recovery: Concerned with applying the necessary corrective action to overcome the error and bring the system back to normal operation.

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Cell or system level

Machine level

Device level

Plant level

Enterprise level

Level of automation

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AUTOMATION IN PRODUCTION SYSTEMS

1.5 LEVELS OF AUTOMATION


1.5 LEVELS OF AUTOMATION 1) Device level• The lowest level and it includes the actuators, sensors and other hardware

components that comprise the machine level.• The devices are combined into the individual control loops of the machine.

Example: the feedback control loop for one axis of a CNC machine.

2) Machine level• Hardware at the device level is assembled into individual machines. Example:

CNC machine tools and similar production equipment, industrial robot and AGV.• Control function at this level includes performing the sequence of steps in the

program of instructions in the correct order and making sure that each step is properly executed.

3) Cell or system level• Manufacturing cell or system level, this cell operates under instructions from the

plant level. It is a group of machines or workstations connected and supported by a material handling system, computers, and other equipment appropriate to the manufacturing process.

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4) Plant level• This is the factory or production systems level. It received instructions from the

corporate information system and translates them into operational plans for production.

• The functions include: order processing, process planning, inventory control, purchasing, material requirement planning, shop floor control and quality control.

5) Enterprise level• This is the highest level, consisting of the corporate information system. It

concerned with all of the function necessary to manage the company: marketing and sales, accounting, design, research, aggregate planning and master production scheduling.

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1.6 REASON FOR AUTOMATED AND NOT AUTOMATED1.6.1 REASON FOR AUTOMATED

• To mitigate the effects of labor shortages: There is a general shortage of labor in many advanced nations, and this has stimulated the development of automated operations as a substitute for labor.

• High cost of labor: May not always make sense to establish plants in countries with low labor cost.

• Increased labor productivity: Value of output per person per hour increases-automating a manufacturing operation usually increases production rate and labor productivity.

• Reduce labor cost: Higher investment in automation has become economically justifiable to replace manual operation. Machines are increasingly being substituted for human labor to reduce unit product cost.

• To reduce or eliminate routine manual and clerical tasks: An argument can be put forth that there is social value in automating operations that routine, boring, fatiguing and possibly irksome. Automating such tasks serves a purpose of improving the general level of working conditions.

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Introduction to Automation Technology• Lower costs: Reduce scrap, lower in-process inventory, superior quality, shorter

lines.

• Reducing manufacturing lead time and reduces work-in-progress: Respond quickly to the customers’ needs and rapid response to changes in design.

• Improve worker safety: By automating a given operation and transferring the worker from activate participation in the process to a supervisory role, the work is made safer.

• Improved product quality: Automation performs the manufacturing process with greater uniformity and conformity to quality specifications. Reduction of fraction defect rate is one of the chief benefits of automation.

• To accomplish processes that cannot be done manually: Certain operation cannot be accomplished without the aid of a machine. These processes have requirements for precision, miniaturization or complexity of geometry that cannot be achieved manually. Example: manufacturing process based on CAD models and rapid prototyping.

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Introduction to Automation Technology• Lower costs: Reduce scrap, lower in-process inventory, superior quality, shorter

lines.

• To avoid the high cost of not automating: The advantage of automating cannot easily be demonstrated on a company’s

authorized from. The benefits of automation often show up in unexpected and intangible ways, such as improved quality, higher sales, better labor relationship and better company image.

Companies that do not automate are likely to find themselves at a competitive disadvantage with their customers, their employees and the general public.

• Competition: Lower prices, better product, better image, better labor relation.

• New process technologies require automation: Example; Robot controlled thermal spray torch for coating engine blocks with steel with atomized steel particles.

• Potential for mass customization and reduced inventory.

• High cost of raw materials

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Introduction to Automation Technology1.6.2 Reason for not automated

• Labor resistance

• Cost of upgraded labor :Example : Chrysler Detroit plant spend 1 million hours of retraining

• Initial investment

• Management of process improvement Intellectual assets versus technological assets Appropriate use of technology A system approach to automation is important Equipment incompatibilities

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Introduction to Automation Technology1.7 Social and Safety Issues in Automation

• Automation has had a notable impact in a wide range of highly visible industries beyond manufacturing.

• In general, automation has been responsible for the shift in the world economy from agriculture to industrial in the 19th century and from industrial to services in the 20th century

Example :

1) Telephone operators have been replaced largely by automated telephone switchboard and answering machines.

2) ATM machine have reduced the need for bank visits to obtain cash and carry out transactions

• The widespread impact of industrial automation raises social issues, among them its impact on employment.

• Automation might appear to devalue labor through its replacement with less-expensive machines

• Automation increase the need for skilled workforce who can make repairs and manage the machinery.

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Introduction to Automation Technology1.7.2 Safety Issues In Automation

One safety issue with automation is : •Minimize human error in a system, increasing the degree and levels of automation also increases the consequences of error.

•With automation we have machine designed by people with high levels of expertise, which operate at speeds well beyond human ability to react.

•Disaster and accident will happened when operated by people with relatively more limited education and not fully trained.

•Ultimately, with increasing levels of automation over ever larger domains of activities, when something goes wrong the consequences rapidly approach the catastrophic.

•This is true for all complex systems however, and one of the major goals of safety engineering for nuclear reactors.

•The important thing designing the automation system is to make safety mechanisms as simple and as foolproof as possible. ENT471 Automation

Introduction to Automation TechnologyQ & A

A beverages plant plan to mass produce orange flavor drink for 4 different brands. All 4 brands using the same aluminum can size but different in printing label on the can. In your opinion what types of automated manufacturing system is most suitable to produce 10,000 can/day and each brand is different in quantity?

Identify the situations in which manual labor is preferred over automation?

(1) The task is technologically too difficult to automate.

(2) Short product life cycle.

(3) Customized product.

(4) To cope with ups and downs in demand.

(5) To reduce risk of product failure.

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Chapter 1 Introduction to Automation Technology

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