8. Прочитайте и переведите текст. Motioncontrol

Let us consider some of major areas covered by motion control.

Parts picking: the manner in which we instruct the robots to pick the product parts. The operation requires high robot repeatability accuracy.

Assembly: programming strategies for the final assembly of parts. This operation requires very high repeatability level.

Transfer: programs, which move the robots from one operation to another. This series of movements is to be carried out as quickly as possible, without collisions, but has no high accuracy demands.

Tooling: programs, which drive the robots to different tools.

Recovery routines: special robot motions, which solve given problems. They include small micromovements and require high accuracy motion.

Cell calibration: automatic calibration routine, which corrects for small robot positional error.

The most common robot motion problem consists in the fact that the robots have difficulty in reaching the necessary position. Possible causes of this effect in the robot program are: 1) Tool center point error. 2) Programming error. 3) Error due to mechanical discrepancies. 4) Non-linearities in robots: inaccurate knowledge of different kinematic parameters. 5) Robot resolvers are uncalibrated – manual recovery.

Error cause 1 is a programming error. It should not really occur if the flexible assembly system has been programmed correctly. Error 2 is easily corrected by recovery routines. Error 4 is usually recovered by robot calibration methods. This error is a real problem in welding application where the robot movement must maintain very high repeatability and absolute accuracy levels. It does not affect assembly, because in this process it is only the final positions, which are of interest. Hence, we can correct this error by cell calibration methods.

Error 3 can also be corrected by cell calibration if one utilizes an object oriented programming environment. This type of error recovery requires robust sensors and object oriented programming environments.

9. Ответьте на вопросы.

1. What are the main areas covered by motion control?

2. What is the main robot motion problem?

3. What are possible causes of the difficulties in reaching the necessary position?

4. How can programming error be corrected?

5. How are non-linearities recovered?

6. How can error due to mechanical discrepancies be corrected?

7. What does the recovery of error due to mechanical discrepancies require?

10. Подберите слова близкие по значению из данного ряда.

movement, update, routine, constraint, motion, limitation, due to, program, because of, modernize.

11. Замените пропуски нужным глаголом (to affect, to transfer, to pick up, to reach, to maintain) в соответствующей форме.

1. The robots…………from one operation to another as quickly as possible.

2. The robot…………the necessary position getting over some difficult problems.

3. During this operation the robot movement…………very high repeatability and absolute accuracy level.

4. All the parts of the tool…………by the robot.

5. If the cause of the error is due to the hardware, then the same error…………the next product of the batch.