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Manufacturing Automation - short answer questions from AMIE exams (Winter 2017)

What is the difference between mechanization and automation?

  • 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 labour, whereas Automation displaces mental labour as well.
  • Mechanization affects one or two industries at a time. Automation is the replacement of human thinking with computers and machines. Automation creates jobs for skilled workers at the cost of unskilled and semi-skilled workers. It affects many industries at the same time.

Give examples of programmable automation and flexible automation.

  • Flexible automation refers to the ability of a robot or system to do various tasks. To change from one task to another, a simple software change, or a change in the commands input to the controller, is all that is necessary. A simple example of flexible automation is a robot arm that can be programmed to insert screws, drill holes, sand, weld, insert rivets, and spray paint on objects in an assembly line. Flexible automation is an extension of programmable automation.
  • Programmable automation is a form of automation for producing products in batches. The products are made in batch quantities ranging from several dozen to several thousand units at a time. For each new batch, the production equipment must be reprogrammed and changed over to accommodate the new product style. The disadvantage with programmable automation is the time required to reprogram and change over the production equipment for each batch of new products.

What do you mean by intermittent transfer mechanism?

Intermittent Transfer: The parts are transported with discontinuous motion. The workstations are fixed in position and parts are moved between stations. All parts are transported at the same time. (Synchronous transfer). Such systems are used in the machining operation, press working operations, and mechanised assembly.

What is a transducer?

A transducer is a device for the conversion of physical quantities to electrical ones. For instance, it converts the physical quantity to voltage or electric current. In general words, it changes the quantities to the form, which is measurable in the form of electrical signals. The primary quantity may be temperature, pressure, level, displacement, etc. The transducer’s output is equal to the input, but it has an electrical form. For instance, a temperature transducer converts the temperature into an equivalent electrical signal. The signal is employed to control the temperature and display it.

Differentiate between precision and accuracy.

  • Accuracy is how close a value is to its True Value. Accuracy is obtained by taking small readings, and these small readings reduce the calculation error.
  • Precision is how repeatable a measurement is. If a given substance is weighed five times and gets 3.2 kg every time, the measurement is very precise but not necessarily accurate. Precision is always independent of accuracy.

Define a robot.

A robot is a type of automated machine that can execute specific tasks with little or no human intervention and with speed and precision.

What is meant by the accuracy of robots?

Accuracy is the ability of a robot to move its end effector to a desired position and orientation that has never been attained before. Technically, no robot or manufacturing process is 100% accurate.

What is the role of group technology in FMS?

Group technology is a rapidly developing productivity improvement tool that can have a significant impact on the development of totally integrated manufacturing facilities and flexible manufacturing systems. In the flexible manufacturing systems (FMS), parts grouping into families can be performed to simplify the long- and short-horizon planning.

Non-contact sensors.

  • Non-contact sensors refer to ones that have the ability to function without the need to physically touch the object being monitored. 
  • For example, rather than using an oral thermometer to measure a patient’s temperature (which requires the thermometer to be physically placed in the patient’s mouth so that the thermometer bulb can make contact), a nurse or physician may employ an infrared thermometer. This type of thermometer is an example of non-contact sensor technology that uses infrared radiation to establish a temperature reading – thus avoiding the need for direct physical contact to occur.
  • Non-contact sensors, therefore, generally rely on technologies that are based on electrical, magnetic, optical, sonic, or other principles, rather than depending on physical contact or mechanical movement to obtain readings. 
  • The sensors often emit a form of energy such as radiation that can be used to detect a condition without needing physical contact. The object being sensed or detected is usually referred to as the target.

Define repeatability and resolution.

  • Repeatability – describes how well a system or device can reproduce an outcome in unchanged conditions. In some applications, repeatability is more important than accuracy. If the system is repeatable, an error can be mapped and compensated for.
  • Resolution – is the smallest increment the system can display or measure. A system can have a high resolution with poor repeatability and accuracy. Resolution is a primary concern in applications regarding speed control or surface finish.
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