Урок 8

1. Выпишите из словаря транскрипцию и перевод следующих слов. Запомните их произношение и значения.

tool (n), condition (n), wear out (wore, worn) (v), replace (v), recovery (n), eliminate (v), loop (n), closed loop, open loop, solution (n), variety (n), debug (v)

2. Правильно прочитайте интернациональные слова и дайте их русский эквивалент. Посмотрите в словаре, выпишите с переводом и выучите подчёркнутые слова.

control [kən'trəʊl], collision [kə'lɪʒn], a posteriori [əpəs,terɪ'ɒrɪ], magazine [,mægə'zi:n], compensate ['kɒmpenseɪt]

3. Прочитайте ряды однокоренных слов. Переведите их, исходя из значения словообразовательных элементов.

low (a), lower (v)

influence (v), influence (n)

result (n), result (v) in, result (v) from

place (v), place (n), replace (v), replacement (n)

apply (v), application (n)

eliminate (v), eliminated (p.p.), eliminating (pres.p.), elimination (n)

recover (v), recovery (n)

see (v), foresee (v), foreseeable (a)

4. Прочитайте и переведите словосочетания.

process plan, tool condition, machining process parameters, technological adaptive control system, automatic recovery procedure, closed loop system, different control strategies, on-line manufacturing process, process monitoring, new error recovery routine, system downtime, steady state force level

5. Переведите предложения, обращая внимание на разные функции слов на -ing (Приложение 2, табл. 6, 8).

1. Changing the machining process parameters is often used in technological adaptive system.

2. Knowing the influence of the disturbance, the automatic supervision compensates this influence by some changes in the work of the manufacturing system.

3. When designing an automatic supervision and recovery system, there are some factors to be considered.

4. Safety systems, sometimes also called monitoring systems in industry, are on-line diagnosing systems used to prevent break-downs or to minimize the damage caused by catastrophic tool failure.

6. Переведите предложения, обращая внимание на различные глагольные формы (Приложение 2, табл. 6, 7, 8).

1. The disadvantage of this system, as many industrial installations will show, is the frequent number of false alarms often forcing the operator to disconnect the system.

2. Cutting forces for the safety systems are measured with pieso-electric force transducers placed in a measuring plate.

3. The typical indication of a total breakage is a fast increase of the force from the steady-state force level followed by a temporary drop to zero force.

4. Productivity increases from 20% to 75% have been reported, the highest values being for machining operations.

5. The methods of programming robots are presented in order of increasing complexity, the stages reflecting the development of robot system.

7. Прочитайте и переведите текст. Supervisoryactions

Apart from monitoring, a supervisory system should be capable of taking necessary action to influence operation of manufacturing system.

Changing the machining process parameters is the most common action taken in technological adaptive control systems (a change of tool, for example). When automatic changing of the tool condition in the machine tool is not possible the worn out tool may be automatically replaced by a new one. This is an easy operation for machining centers, because they are equipped with magazines for the automatic changing of tools.

In some cases of disturbances, such as collision between the tool and the production equipment, the automatic supervision in manufacturing system must interrupt the machining process as quickly as possible. An automatic recovery procedure may be applied later. This may involve changes to the process plans and certain types of machining operation may be eliminated.

In a typical system of automatic supervision the results of the manufacturing process are measured and necessary corrections are made to the process. In such a closed-loop system the influences of all disturbances on the measured result of manufacturing may be corrected, but a posteriori (that is, after they have already influenced the result). Another solution is to measure the value of the main disturbance and, knowing how it will influence the result, compensate this influence by appropriate changes in the work of the manufacturing systems. In such a supervisory system, only the influence of measured disturbances may be eliminated or reduced.

The automatic supervision in manufacturing systems may have different structures and work according to different control strategies. This is especially true for on-line manufacturing processes. Because of complicated processes and difficulties in process monitoring, a variety of techniques is often used.