Intuitive motion coordinate system for controlling an industrial robot

• US 9,958,862 B2
• Filed: 08/08/2014
• Issued: 05/01/2018
• Est. Priority Date: 05/08/2014
• Status: Active Grant

• Current Assignee: Yaskawa America, Inc. (Yaskawa Electric Corporation)
• Original Assignee: Yaskawa America, Inc. (Yaskawa Electric Corporation)
• Inventors: Kapoor, Chetan, Rajan, Ratheesh
• Primary Examiner(s): MANCHO, RONNIE M
• Application Number:
  US14/455,345
• Publication Number:
  US 20150321351A1
• Time in Patent Office: 1,362 Days
• Field of Search: 700264, 700229, 700253, 700259, 700245, 700 98, 901 30, 901 47, 901 3
• CPC Class Codes: B25J 9/161 Hardware, e.g. neural networks, fuzzy logic, interfaces, processor
• CPC Class Codes: G05B 19/427 Teaching successive positions by tracking the position of a joystick or handle to control the positioning servo of the tool head, master-slave control G05B19/423 takes precedence
• CPC Class Codes: G05B 2219/39445 Select between jog modes, user, robot coordinates, tool, system feed, joint feed
• CPC Class Codes: Y10S 901/06 Communication with another machine
• CPC Class Codes: Y10S 901/14 Arm movement, spatial
• CPC Class Codes: Y10S 901/28 Joint
• CPC Class Codes: Y10S 901/30 End effector

Abstract

A method and apparatus for controlling an industrial robot relative to an intuitive motion coordinate system. The current 3D position of a touch-screen teach pendant relative to the robot is sensed, and an operator-centric frame of reference is developed relative to the robot-centric frame of reference. A simulacra of the robot is generated, oriented so as to correspond with an operator view of the robot from the current position of the controller, and displayed on the pendant. A motion-control construction, generated and displayed on the pendant, is adapted to receive jog commands from the operator indicative of a respective incremental movement of the simulacra in the operator-centric frame of reference. Each jog command is transformed from the operator-centric frame of reference to the robot-centric frame of reference, and the robot moved in accordance with the transformed jog command. Movement of the pendant relative to the robot is sensed and, in response, the displayed simulacra is reoriented to correspond to the new position of the pendant relative to the robot as viewed by the operator.

Claims

1. A method for controlling a multi-axis robot using an operator interface adapted to interact with an operator, the operator interface comprising a teach pendant having an input element, a display element, and a sensor element adapted to sense a current 3D position of the pendant, the method comprising the steps of:

[1] generating a simulacra of the robot for display on the display element;

[2] determining a current 3D position of the robot relative to a robot-centric first frame of reference;

[3] using the sensor element to sense the current 3D position of the pendant relative to the first frame of reference;

[4] developing an operator-centric second frame of reference corresponding to the current 3D position of the pendant with respect to the first frame of reference;

[5] orienting the simulacra in the second frame of reference to correspond with an operator view of the robot from the current 3D position of the pendant;

[6] displaying the oriented simulacra on the display element;

[7] receiving from the operator via the input element a jog command indicative of a respective incremental movement of the simulacra in the second frame of reference;

[8] transforming the jog command from the second frame of reference to the first frame of reference; and

[9] moving the robot in the first frame of reference in accordance with the transformed jog command.

2. The method of claim 1 further comprising the steps of:

[10] displaying on the display element a motion-control construct representing a movement of the robot;

wherein step [7] is further characterized as;

[7] receiving from the operator via the motion-control construct displayed on the display element a jog command indicative of a respective incremental movement of the simulacra in the second frame of reference.

3. The method of claim 2 further comprising the steps of:

[11] sensing a change in the current 3D position of the pendant relative to the first frame of reference;

[12] translating the second frame of reference to correspond to the current 3D position of the pendant with respect to the first frame of reference; and

[13] returning to step [5].

10. Apparatus configured to perform the method according to any preceding claim.

11. A computer readable medium including executable instructions which, when executed by a computer, cause the computer to perform a method according to any one of claims 1 to 9.

4. A method for controlling a multi-axis robot using an operator interface adapted to interact with an operator, the operator interface comprising a teach pendant having an input element, a display element, and a sensor element adapted to sense a current 3D position of the pendant, the method comprising the steps of:

[1] generating a simulacra of the robot for display on the display element;

[2] determining a current 3D position of the robot relative to a robot-centric first frame of reference;

[3] using the sensor element to sense the current 3D position of the pendant relative to the first frame of reference;

[4] developing an operator-centric second frame of reference corresponding to the current 3D position of the pendant with respect to the first frame of reference;

[5] orienting the simulacra in the second frame of reference to correspond with an operator view of the robot from the current 3D position of the pendant;

[6] displaying the oriented simulacra on the display element;

[7] displaying on the display element a motion-control construct suggestive of a movement of the simulacra;

[8] receiving from the operator via the motion-control construct displayed on the display element a jog command indicative of a respective incremental movement of the simulacra in the second frame of reference;

[9] transforming the jog command from the second frame of reference to the first frame of reference;

[10] moving the robot in the first frame of reference in accordance with the transformed jog command;

[11] sensing a change in the current 3D position of the pendant relative to the first frame of reference;

[12] translating the second frame of reference to correspond to the current 3D position of the pendant with respect to the first frame of reference; and

[13] returning to step [5].

5. A computer-implemented method for controlling a multi-axis robot using an operator interface adapted to interact with an operator, the operator interface comprising a teach pendant having an input element, a display element, and a sensor element adapted to sense a current 3D position of the pendant, the method comprising the steps of:

[1] determining a current 3D position of the robot relative to a robot-centric first frame of reference;

[2] using the sensor element to sense the current 3D position of the pendant relative to the first frame of reference;

[3] developing an operator-centric second frame of reference corresponding to the current 3D position of the pendant with respect to the first frame of reference;

[4] displaying on the display element a motion-control construct suggestive of a movement of the robot;

[5] receiving from the operator via the motion-control construct a jog command indicative of a respective incremental movement of the robot in the second frame of reference;

[6] transforming the jog command from the second frame of reference to the first frame of reference; and

[7] moving the robot in the first frame of reference in accordance with the transformed jog command.

6. The method of claim 5 further comprising the steps of:

[4.1] generating a simulacra of the robot for display on the display element;

[4.2] orienting the simulacra in the second frame of reference to correspond with an operator view of the robot from the current 3D position of the pendant; and

[4.3] displaying the oriented simulacra on the display element in association with the displayed motion-control construct.

7. The method of claim 6 further comprising the steps of:

[8] sensing a change in the current 3D position of the pendant relative to the first frame of reference;

[9] translating the second frame of reference to correspond to the current 3D position of the pendant with respect to the first frame of reference; and

[10] returning to step [4].

8. A method for using a computer to develop a simulacra of a multi-axis robot for display on a display screen integrated into a teach pendant adapted for use by an operator to control the robot, the method comprising the steps of:

[1] generating a simulacra of the robot for display on the display screen;

[2] determining a current 3D position of the robot relative to a robot-centric first frame of reference;

[3] sensing a current 3D position of the pendant relative to the first frame of reference;

[4] developing an operator-centric second frame of reference corresponding to the current 3D position of the pendant with respect to the first frame of reference;

[5] orienting the simulacra in the second frame of reference to correspond with an operator view of the robot from the current 3D position of the pendant; and

[6] displaying the oriented simulacra on the display screen.

9. The method of claim 8 further comprising the steps of:

[7] sensing a change in the current 3D position of the pendant relative to the first frame of reference;

[8] translating the second frame of reference to correspond to the current 3D position of the pendant with respect to the first frame of reference; and

[9] returning to step [5].