Device and method for workpiece calibration

• US 7,218,995 B2
• Filed: 05/11/2006
• Issued: 05/15/2007
• Est. Priority Date: 05/13/2005
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Jahn, Dirk, Vitr, Mirco
• Primary Examiner(s): Masinick; Michael D.
• Application Number:
  US11/432,243
• Publication Number:
  US 20060259180A1
• Time in Patent Office: 369 Days
• Field of Search: 700/186, 700/192, 700/259
• US Class Current: 700/259
• CPC Class Codes: G06T 7/75 involving models

Abstract

The invention relates to a device and a method for determination of location information of a workpiece. To enable rapid calibration of a relative position of the workpiece (1) in relation to a tool provided for processing said workpiece, it is proposed that the device

• • features a camera for recording at least a partial area of the workpiece,
  • first processing means for determination of geometrical parameters on the basis of the partial area recorded by the camera,
  • a memory for a geometry model of the workpiece and
  • second processing means for determining the location in-formation of the workpiece by reconciling the geometrical parameters with the geometry model, with the location information being provided for determining the position of the workpiece in relation to a tool pro-vided for processing it.

Claims

1. A device for determining location information of a workpiece, comprising:

a camera for recording at least a partial area of the workpiece;

a first processing unit for determining geometrical parameters of the workpiece based on the recorded partial area recorded;

a memory having a geometry model of the workpiece; and

a second processing unit for calculating the location information by matching the geometrical parameters to the geometry model, wherein the location information includes information for positioning the workpiece relative to a tool provided for processing the workpiece.

2. The device in accordance with claim 1, wherein the first processing unit includes an image processing algorithm.

3. The device in accordance with claim 1, further comprising a light source for illuminating the workpiece, wherein the first processing unit includes a triangulation algorithm.

4. The device in accordance with claim 1, wherein the second processing unit is configured to detect characteristic elements of the workpiece and to detect perspective distortions of the characteristic elements relative to the geometry model.

5. The device in accordance with claim 1, wherein the second processing unit is configured to determine a matrix representing a displacement or a rotation of the workpiece relative to a reference position.

6. The device in accordance with claim 5, wherein a numerical control unit for controlling the tool is calibrated based on the matrix.

7. The device in accordance with claim 1, further comprising a precision sensor for precisely measuring the workpiece after the location information has been calculated.

8. The device in accordance with claim 7, further comprising a transport device for guiding the precision sensor or the workpiece into a starting position from which the precise measurement is started.

9. A machine tool device for automatically processing a workpiece, comprising:

a device for determining location information of a workpiece, the device comprising;

a camera for recording at least a partial area of the workpiece;

a first processing unit for determining geometrical parameters of the workpiece based on the recorded partial area recorded;

a memory having a geometry model of the workpiece; and

a second processing unit for calculating the location information by matching the geometrical parameters to the geometry model, wherein the location information includes information for positioning the workpiece relative to a tool provided for processing the workpiece; and

a numerical control device for controlling the tool based on the calculated location information.

10. A method of determining location information of a workpiece, comprising:

recording at least a partial area of the workpiece using a camera;

determining geometrical parameters of the workpiece based on the recorded partial area;

calculating the location information by matching the geometrical parameters to a stored geometry model of the workpiece; and

determining a position of the workpiece relative to a tool provided for processing the workpiece based upon the location information.

11. The method in accordance with claim 10, wherein determining geometrical parameters are determined by an image processing algorithm.

12. The method in accordance with claim 10, wherein determining geometrical parameters are determined by an triangulation algorithm.

13. The method in accordance with claim 10, wherein calculating the location information includes detecting characteristic elements of the workpiece and detecting perspective distortions of the characteristic elements relative to the geometry model.

14. The method in accordance with claim 10, wherein calculating the location information includes determining a matrix representing a displacement or a rotation of the workpiece relative to a reference position.

15. The method in accordance with claim 14, further comprising calibrating a numerical control unit for controlling the tool based upon the matrix.

16. The method in accordance with claim 10, further comprising precisely measuring the workpiece location after the location information has been determined, with a precision sensor.