Positioning control system for moving element and laser drilling machine

Abstract

A positioning control system for positioning a moving element on a basis of position command data is provided with a feedback loop. The system is also provided with a loop gain modifier for determining a loop gain, which is to be used in a following positioning operation, on a basis of a difference between an amount of overshoot measured in a current positioning operation and a predetermined tolerance or on a basis of a difference between an amount of overshoot measured in a current positioning operation and a first predetermined tolerance and a difference between an amount of undershoot measured in the current positioning operation and a second predetermined tolerance. The first and second tolerances may preferably be the same in absolute value. The moving element may specifically be a steerable mirror for drilling holes in a work by reflecting a laser beam. Also disclosed is a laser drilling machine including the system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a steerable mirror control system in Example 1 of the present invention.

FIG. 2 is a flow chart describing operations of a loop gain modifier in the steerable mirror control system of FIG. 1.

FIG. 3 is a diagram showing an illustrative tracking-error response waveform obtained by the steerable mirror control system of FIG. 1.

FIG. 4 is a diagram depicting another illustrative tracking-error response waveform obtained by the steerable mirror control system of FIG. 1.

FIG. 5 is a flow chart describing operations of a loop gain modifier in a steerable mirror control system in Example 2 of the present invention.

FIG. 6 is a diagram showing an illustrative tracking-error response waveform obtained by the steerable mirror control system of FIG. 5.

FIG. 7 is a schematic diagram of a laser drilling machine according to the present invention.

Claims

1. A positioning control system for positioning a moving element on a basis of position command data, said positioning control system being provided with a feedback loop, comprising: a loop gain modifier for determining a loop gain, which is to be used in a following positioning operation, on a basis of a difference between an amount of overshoot measured in a current positioning operation and a predetermined tolerance.

2. A positioning control system according to claim 1, wherein based on a distance or angle over which said moving element is to be moved in said current positioning operation, said loop gain modifier determines whether or not a modification is to be performed.

3. A positioning control system according to claim 2, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

4. A positioning control system according to claim 1, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

5. A positioning control system for positioning a moving element on a basis of position command data, said positioning control system being provided with a feedback loop, comprising: a loop gain modifier for determining a loop gain, which is to be used in a following positioning operation, on a basis of a difference between an amount of overshoot measured in a current positioning operation and a first predetermined tolerance and a difference between an amount of undershoot measured in said current positioning operation and a second predetermined tolerance.

6. A positioning control system according to claim 5, wherein based on a distance or angle over which said moving element is to be moved in said current positioning operation, said loop gain modifier determines whether or not a modification is to be performed.

7. A positioning control system according to claim 6, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

8. A positioning control system according to claim 5, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

9. A positioning control system according to claim 5, wherein an absolute value of said first tolerance and an absolute value of said second tolerance are the same with each other.

10. A positioning control system according to claim 9, wherein based on a distance or angle over which said moving element is to be moved in said current positioning operation, said loop gain modifier determines whether or not a modification is to be performed.

11. A positioning control system according to claim 10, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

12. A positioning control system according to claim 9, wherein said moving element is a steerable mirror for drilling holes in a work by reflecting a laser beam.

13. A laser drilling machine comprising a positioning control system according to claim 3.

14. A laser drilling machine comprising a positioning control system according to claim 4.

15. A laser drilling machine comprising a positioning control system according to claim 7.

16. A laser drilling machine comprising a positioning control system according to claim 8.

17. A laser drilling machine comprising a positioning control system according to claim 11.

18. A laser drilling machine comprising a positioning control system according to claim 12.