Robot off-line simulation apparatus

• US 20050004709A1
• Filed: 07/02/2004
• Published: 01/06/2005
• Est. Priority Date: 07/03/2003
• Status: Active Grant

• Current Assignee: Fanuc Ltd (Fanuc Corporation)
• Original Assignee: Fanuc Ltd (Fanuc Corporation)
• Inventors: Kosaka, Tetsuya, Nagatsuka, Yoshiharu, Watanabe, Atsushi
• Granted Patent: US 7,512,459 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: B25J 9/1664 characterised by motion, path, trajectory planning
• CPC Class Codes: B25J 9/1671 characterised by simulation, either to verify existing program or to create and verify new program, CAD/CAM oriented, graphic oriented programming systems
• CPC Class Codes: G05B 2219/40317 For collision avoidance and detection
• CPC Class Codes: G05B 2219/40465 Criteria is lowest cost function, minimum work path
• CPC Class Codes: G05B 2219/40515 Integration of simulation and planning
• CPC Class Codes: G05B 2219/40629 Manipulation planning, consider manipulation task, path, grasping

Abstract

A robot off-line simulation apparatus that allows a person to know an optimum placement for a robot, an operation margin index, etc. before going to an actual working site. Provisional robot placing positions are selected using data about a given sequence of task points (operation path), etc. The conditions for selection are (i) that solution to the inverse kinematics should be found regarding the entire sequence of task points, (ii) that the robot should not interfere with a peripheral device, and (iii) that regarding all the axes of the robot, the operation margin index should satisfy a criterion value. Simulation is performed according to operation programs under the condition that the robot is placed at each of the provisional placing positions, where data about cycle time, duty, energy value, change in acceleration/speed, etc. is collected. Using the collected data, evaluation of operation is performed regarding each of the provisional placing positions, and those provisional placing positions which allow good operation are identified as placing positions ensuring the robot operation. Further, using an evaluation function in which each aspect is given a weighting, the placing positions ensuring the robot operation are reduced to optimum placing positions ensuring the robot operation.

Claims

1. A robot off-line simulation apparatus for simulating an operation of a robot placed with a workpiece and a peripheral device in a three-dimensional space by simultaneously displaying three-dimensional models of the robot, the workpiece and the peripheral device on a screen, comprising:

means for determining discrete positions at which a base of the robot is to be placed, the robot with the base placed at each of the discrete positions being reachable to a preset sequence of task points for performing tasks on the workpiece;

means for obtaining an index representing an operation margin of the robot when the robot with the base placed at each of the discrete positions reaches the sequence of task points; and

means for displaying the discrete positions and the obtained indices for the respective discrete positions on the screen.

2. A robot off-line simulation apparatus according to claim 1, wherein each of the task points is given one of a three-dimensional position, a combination of the three-dimensional position and a direction vector, and a combination of the three-dimensional position and an orientation, for performing the task on the workpiece by the robot.

3. A robot off-line simulation apparatus according to claim 1, further comprising means for determining whether or not the robot with the base placed at each of the discrete positions interferes with one of the workpiece and the peripheral device when the robot reaches to the sequence of task points, and means for displaying a result of the determination on the screen.

4. A robot off-line simulation apparatus according to claim 1, further comprising means for simulating an operation of the robot with the base placed at each of the discrete positions according to an operation program, to obtain an evaluation value regarding an operation performance of the robot using an evaluation function, means for selecting at least one of the discrete positions for which the evaluation values are preferable, and means for displaying the selected discrete positions on the screen.

5. A robot off-line simulation apparatus according to claim 4, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to cycle time.

6. A robot off-line simulation apparatus according to claim 4, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to duty.

7. A robot off-line simulation apparatus according to claim 4, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to energy.

8. A robot off-line simulation apparatus according to claim 4, further comprising means for determining whether or not the robot with the base placed at each of the discrete positions interferes with one of the workpiece and the peripheral device when the robot reaches to the sequence of task points, and means for displaying a result of the determination on the screen.

9. A robot off-line simulation apparatus for simulating an operation of a robot placed with a workpiece and a peripheral device in a three-dimensional space by simultaneously displaying three-dimensional models of the robot, the workpiece and the peripheral device on a screen, comprising:

means for determining discrete positions at which a base of the robot is to be placed, the robot with the base placed at each of the discrete positions being reachable to a preset operation path of the robot for performing tasks on the workpiece;

means for obtaining an index representing an operation margin of the robot when the robot with the base placed at each of the discrete positions reaches the operation path; and

means for displaying the discrete positions and the obtained indices for the respective discrete positions on the screen.

10. A robot off-line simulation apparatus according to claim 9, wherein the operational path is given one of a direction vector and an orientation for performing the task on the workpiece by the robot.

11. A robot off-line simulation apparatus according to claim 9, further comprising means for determining whether or not the robot with the base placed at each of the discrete positions interferes with one of the workpiece and the peripheral device when the robot reaches to the operation path, and means for displaying a result of the determination on the screen.

12. A robot off-line simulation apparatus according to claim 9, further comprising means for simulating an operation of the robot with the base placed at each of the discrete positions according to an operation program, to obtain an evaluation value regarding an operation performance of the robot using an evaluation function, means for selecting at least one of the discrete positions for which the evaluation values are preferable, and means for displaying the selected discrete positions on the screen.

13. A robot off-line simulation apparatus according to claim 12, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to cycle time.

14. A robot off-line simulation apparatus according to claim 12, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to duty.

15. A robot off-line simulation apparatus according to claim 12, wherein the evaluation function is prepared for evaluating the operation performance of the robot with respect to energy.

16. A robot off-line simulation apparatus according to claim 12, further comprising means for determining whether or not the robot with the base placed at each of the discrete positions interferes with one of the workpiece and the peripheral device when the robot reaches to the operation path, and means for displaying a result of the determination on the screen.