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Exercise 2.3 Recall Information

After reading the text, tell which of the following statements about automation are true and which are false. Correct the false statements to make them true.

1 ___ Automation is a technology in which a process is accomplished by means of programmed instructions.

2 ___ The instructions are not combined with automatic feedback control.

3 ___ Automatic feedback control is used to ensure the proper execution of the instructions.

4 ___ Automation can be used in a wide variety of application areas.

5 ___ There are three basic components of an automated system: (1) power to accomplish the process, (2) machine programming, and (3) feedback controls.

6 ___ Automated system must not include three basic components.

7 ___ Some certain systems may operate by means of open-loop control rather than feedback control.

8 ___ An automated system performs some action to accomplish its function, and the action requires power.

9 ___ The actions performed by an automated system can be divided into two categories: processing and movement or positioning.

10 ___ The use of electric power doesnt have any benefits in the operation of an automated system.

 

Exercise 2.4 Increase Your Vocabulary

 

You may have come across the following words before but perhaps not used in quite this way. Suggest words or phrases which might replace them:

 

by means of to be accomplished

to coin something open-loop control

rather than schematically

cooling to convert occur

to be capable of feedback control

to apply for pneumatic

with the exception of mechanized production

solidification step-by-step lines

molding execution

 

 

Exercise 2.5 Read for Specific Information

 

Read and translate the statements. Correct the statements if they are wrong.

 

1 Automation technology is not applied in manufacturing operations.

2 There are two basic components of an automated system: power to accomplish the process, machine programming.

3 In fact, Del Harder, an engineering manager at Ford Motor Company in 1946, coined the term automation to describe the use of automatic devices and controls in mechanized production lines.

4 An automated system performs some action to accomplish its function, and the action requires power.

5 Use of electric power does not have benefits in the operation of an automated system.

 

 

Exercise 2.6 Choose the Correct Definitions for Terms

 

Match each term with its definition. Translate these definitions into Ukrainian.

 

INSTRUCTION one of several parts of which something is made
TECHNOLOGY performing a task, etc. or putting a plan into action
COMPONENT detailed information on how you should use or do something
CONTROL power and ability to make somebody or something do what you want
EXECUTION the scientific knowledge and/or equipment that is needed for a particular industry

Exercise 2.7 Learn to Write a Summary

Give a short summary of the text in writing.

 

 

Exercise 2.8 Controlled Practice

 

Find sentences with Modal verbs. Translate them into Ukrainian. Write these sentences in Past and Future Tenses.

Exercise 2.9 Focus on Translation

Translate the following sentences into English.

1 , .

2 ֳ , , .

3 , , .

Exercise 2.10 Discussion Point

Talk over the importance of three basic components of an automated system. What is the most important basic component and why?

 

 

Unit 3

Feedback Controls

Pre-reading Task

 

Scan the text for answering the following questions.

1 Why are feedback controls widely used in automated systems?

2 What are five basic components of a feedback control system?

 

Text

Feedback controls are widely used in automated systems to ensure that the programmed commands have been properly executed. A feedback control system consists of five basic components (Figure 1.2); (1) input signal, (2) process, (3) output, (4) feedback sensing elements, and (5) controller and actuators. The input signal represents the desired value of the process output.

Figure 3.1 Diagram of a feedback control system.

The output is some variable that is being measured and compared with the input. The output value is a function of the process. Sensing elements close the loop between output and input. Finally, the controller and actuators compare the output with the desired input and make adjustments in the process to reduce the difference between them.

An important example of feedback control in manufacturing is a positioning system. A typical purpose of the positioning system in production operations is to move a work part to a desired location relative to a tool or work head. Examples of positioning systems include numerical control machine tools, spot welding robots, electronic component insertion machines, and coordinate measuring machines. In operation, a programmed instruction directs the positioning system to move the worktable to a certain location defined by coordinate values in an axis system (e.g., x and y values in a Cartesian coordinate system). For an x-y positioning table, two feedback control systems are required, one for each axis. A common actuator for each axis in such a system consists of a leadscrew driven by an electric motor; rotation of the leadscrew is converted into translation of the table. The controller receives the coordinate value as its input from the program and transmits a signal to the motor to drive the leadscrew. As the table moves closer to the desired location, the difference between actual position and input x -value is reduced. The actual position is sensed by a feedback sensor, commonly an optical encoder. In the ideal, the controller drives the motor until the actual table position is equal to the desired input position.

As the example of the positioning system indicates, the process input is determined by the control program in an automated system. The program consists of a sequence of steps, each step in turn being sent as an input to the controller and actuator of the system. As each step is executed, the next step is then transmitted. In this step-by-step manner, the program is executed.

Post-Text Exercises

Exercise 3.1 Read and Translate the Text into Ukrainian

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