Q. 1. Define Automation.
Ans. Automation may be defined in various ways:
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Automation is a process in industry where various, production
operations are converted from a manual process to an automated process.
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Automation can be defined as a technology concerned with the
application of mechanical, electronic and computer based systems to
operate and control production.
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Automation can generally be defined as the process of following a
predetermined sequence of operations with little or no human labor,
using specialized equipment and devices than perform and control
manufacturing processes.
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Automation in its full sense, is achieved through the use of variety
of devices, sensors, actuators techniques and equipments that are
capable of observing the manufacturing processes, making decisions
concerning the changes that need to be made in the operation and
controlling all aspects of it.
Q. 2. Differentiate between Automation and Mechanization.
Ans.
Mechanization refers to the replacement of human power with mechanical
power of some form. The use of hand power tools is not an example of
mechanization.
Automation
and mechanization are often confused with each other; Mechanization
saves the use of human muscles whereas automation saves the use of
human judgement.
Mechanization displaces physical labor, whereas Automation displaces mental labor as well.
Mechanization
affects one or two industries at a time. Automation is the replacement
of human thinking with computers and machines. Automation create jobs
for skilled workers at the cost of unskilled and semi skilled workers.
It affects many industries at the same time.
mechanization
Q. 3. List some major points why automation is required in industry.
Ans. Reasons for Automation:
1. To increase labor productivity: Automating
a manufacturing operation usually increases production rate and labor
productivity. This means greater output per hour of labor input.
2. To reduce labor cost: Due
to ever increasing labor cost, higher investment in automation has
become economically justifiable to replace manual operation.
3. To mitigate the effects of labor shortage: There is a general shortage of labor in many advanced nations and this has stimulated automation.
4. To reduce or eliminate routine manual and clerical tasks:
Tasks that are routine, boring, fatiguing and possible irksome.
Automating such tasks serve a purpose of improving the general level of
working condition.
5. To improve worker safety: By automating a given operation and transferring the worker from active participation in the process to a supervisory role.
6. To improve product quality: Automation
not only results in higher production rate than manual operations; it
also performs the manufacturing process with greater quality.
7. To reduce manufacturing lead time: Automation helps to reduce the elapsed time between customer order and product delivery.
8. To accomplish processes that cannot be done manually: Certain operations cannot be accomplished without the aid of machine automation
Q.4 . What are different types of Automation? (OR) Compare hard automation and soft automation.
Ans. Automation of production systems can be classified into three basic types:
1. Fixed automation (Hard Automation)
2. Programmable automation (Soft Automation)
3. Flexible automation.
1. Fixed automation (Hard automation): Fixed
automation refers to the use of special purpose equipment to automate a
fixed sequence of processing or assembly operations. Each of the
operation in the sequence is usually simple, involving perhaps a plain
linear or rotational motion or an uncomplicated combination of two. It
is relatively difficult to accomodate changes in the product design.
This is called hard automation.
Advantages:
1. Low unit cost
2. Automated material handling
3. High production rate.
Disadvantages:
1. High initial Investment
2. Relatively inflexible in accommodating product changes.
2. Programmable automation: In
programmable automation, the production equipment is designed with the
capability to change the sequence of operations to accomodate
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.
Advantages:
1. Flexible to deal with design variations.
2. Suitable for batch production.
Disadvantages:
1. High investment in general purpose equipment
2. Lower production rate than fixed automation.
Example: Numerical controlled machine tools, industrial robots and programmable logic controller.
3. Fixed Automation: (Soft automation): Flexible
automation is an extension of programmable automation. A flexible
automation system is capable of producing a variety of parts with
virtually no time lost for changeovers from one part style to the next.
There is no lost production time while reprogramming the system and
altering the physical set up.
Advantages:
1. Continuous production of variable mixtures of product.
2. Flexible to deal with product design variation.
Disadvantages:
1. Medium production rate
2. High investment.
3. High ‘unit cost relative to fixed automation.
Q. 5. What are the advantages and disadvantages of automation?
Ans. Advantages:
1. Lesser working hours for the same production.
2. Reduced lead time.
3. Elimination of set up time.
4. Safer working conditions.
5. Better product quality.
6. Increased standard of living.
Disadvantages:
1. Lower skill levels of workers.
2. High initial investment.
3. Retrechment or unemployment.
4. Not suitable for short product life cycle.
5. Not economically justifiable for small scale production.
Q. 6. Discuss the concept of low cost automation with the help of suitable example.
Ans. Low
cost automation is a technology that creates some degree of automation
around the existing equipment, tools, methods, people etc. using
mostly standard component available in the market.
—
A wide range of activities such as loading, feeding, clamping,
machining, welding, forming and packing can be subjected to low cost
automation
—
Low cost automation is very useful for process industries,
manufacturing, chemical, oil or pharmaceuticals. Many operations in
food processing can also be done by low cost automation system.
Benefits:
1. Reduce manual controls without changing the basic set up.
2. Low investment
3. Increased labor productivity
4. Consistent quality
5. Better utilization of material.
Q. 7. (a) Discuss the basic elements of an automated system.
(b) Describe with neat sketch close loop and open loop control system.
Ans. (a) Basic elements of an automated system:
1. Power to accomplish the process and operate the system.
2. A program of instructions to direct the process.
3. A control system to actuate the instructions.
Elements of Automated system
1. Power source: An
automated system is used to operate some process and power is required
to drive the process as well as controls. There are many sources of
power available, but the most commonly used power is electricity. The
actions performed by automated systems are generally of two types:
(a)Processing
(b)Transfer and positioning
In
the first case, energy is applied to accomplish some processing
operation on some entity. The process may involve shaping, moulding or
Loading and unloading. All these actions need power to transfer the
entity from one state or condition into more valuable state or
condition.
The
second type of actions-transfer and positioning. In these cases, the
product must generally be moved from one location to another during the
series of processing steps.
2. Program of instructions: The
actions performed by an automated process are defined by a set of
instructions known as process. The programmed instructions determine the
set of actions that is to be done automatically by the system. The
program specifies what automated system should do and how its various
components must function in order to accomplish the desired results.
3. Control system: The control element of the automated system executes the program of instructions.
The controls in an automated system can be:
(a)Closed loop
(b)Open loop.
(b) Closed loop control system: It
is also known as a feedback control system. In this 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 input.
1. Input parameter: as set point, represents the desired value of output.
2. Output variables: actual value of parameter.
3. Sensors: A sensor is used to measure the output variable and close the loop
4. Between input and output: It performs feedback function.
5. Controller: The
controller compares the output with the input and makes the required
adjustment in the process to reduce the difference between them.
6. Actuator: The
adjustment being done with one or more actuator which are the hardware
devices that physically carry out the control actions such. electric
motor, cylinder etc.
Closed loop control system
Open loop control system: It
is without the feedback loop. In this case the controls operates
without measuring the output variables, so no comparison is made between
the actual value of the output and desired input parameters There is
always risk that the actuator will not have intended effect on the
process.
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