Robot adaptive placement system with end-effector position estimation

Patent metadata

Field	Value
Publication number	US-10058996-B2
Application number	US-201514944603-A
Country	US
Kind code	B2
Filing date	Nov 18, 2015
Priority date	Nov 18, 2014
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A method including, based at least partially upon a command transmission to at least one motor of a robot, estimating deflection for at least one member of the robot during movement of the robot; based at least partially upon the estimated deflection, determining calculated end effector coordinates for an end effector of the robot; and based at least partially upon the calculated end effector coordinates, adjusting movement of the robot for placing a substrate, located on the robot, at a desired location.

First claim

What is claimed is:

1. A method comprising:
sensing a substrate by at least one sensor as the substrate is moved past the at least one sensor, where the substrate is on an end effector of a robot;
calculating, by a controller, model end effector coordinates of the end effector when the at least one sensor senses the substrate moving past the at least one sensor, where the controller comprises at least one processor and at least one non-transitory memory, where an adaptive placement system is provided configured to use the sensing of the substrate by the at least one sensor and to use of the calculated model end effector coordinates to control placing of the substrate at a desired position;
estimating by the controller deflection for at least one member of the robot during movement of the robot;
based at least partially upon the estimated deflection, determining by the controller estimated end effector coordinates for the end effector of the robot;
generating by the controller at least one signal, which is based at least partially upon the estimated end effector coordinates; and
adjusting movement of the robot by the adaptive placement system based at least partially upon the at least one signal generated by the controller, the sensing of the substrate by the at least one sensor, and the calculated model end effector coordinates for placing the substrate at a desired location.

2. A method as in claim 1 where the estimating by the controller is based, at least partially, upon a command transmission to at least one motor of the robot, where the command transmission comprises a command torque transmission which is transmitted to the at least one motor to generate a predetermined torque vector.

3. A method as in claim 1 where the estimated deflection for the at least one member of the robot comprises at least one of:
a flexible frame member of a drive section of the robot,
a flexible drive shaft of the at least one motor,
a flexible link of an arm of the robot,
a flexible joint between links of the arm of the robot, and
an elastic belt or band of the arm of the robot.

4. A method as in claim 1 where the estimating comprises at least one of:
estimation of flexibility effects using dynamic modeling,
estimation of flexibility effects using a state observer,
estimation of belt positioning error effects, and
direct measurement of flexibility effects using at least one auxiliary sensor.

5. A method as in claim 1 where the estimating of the deflection is based, at least partially, upon location information from at least one sensor regarding at least one of:
a portion of the robot, and
the substrate carried by the robot.

6. A method as in claim 1 where the adjusting of movement of the robot is further based upon forward kinematics determination of the end effector which subsequently provides modified estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

7. A method as in claim 1 where the adjusting movement of the robot comprises providing the estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

8. A method as in claim 1 where the estimated end effector coordinates are provided to a robot location sensing system and/or to a substrate location sensing system, which subsequently provides modified estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

9. An apparatus comprising:
at least one processor; and
at least one non-transitory memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to:
calculate model end effector coordinates of an end effector of a robot when at least one sensor senses a substrate moving past the at least one sensor, where the substrate is on the end effector, and where an adaptive placement system is provided configured to use the sensing of the substrate by the at least one sensor and to use the calculated model end effector coordinates to control placing of the substrate at a desired position;
estimate deflection for at least one member of the robot during movement of the robot;
based at least partially upon the estimated deflection, determine estimated end effector coordinates for the end effector of the robot; and
generate at least one signal which is based at least partially upon the estimated end effector coordinates; and
adjust movement of the robot by the adaptive placement system based at least partially upon the at least one signal generated by the controller, the sensing of the substrate by the at least one sensor, and the calculated model end effector coordinates for placing the substrate at a desired location.

10. An apparatus as in claim 9 where the estimating of the deflection comprises a command transmission to at least one motor of the robot being used as an input to estimate the deflection, and where the command transmission comprises a command torque transmission which is transmitted to the at least one motor to generate a predetermined torque vector.

11. An apparatus as in claim 9 where the estimated deflection for the at least one member of the robot comprises at least one of:
a flexible frame member of a drive section of the robot,
a flexible drive shaft of the at least one motor,
a flexible link of an arm of the robot,
a flexible joint between links of the arm of the robot, and
an elastic belt or band of the arm of the robot.

12. An apparatus as in claim 9 where the estimating comprises at least one of:
estimation of flexibility effects using dynamic modeling,
estimation of flexibility effects using a state observer,
estimation of belt positioning error effects, and
direct measurement of flexibility effects using at least one auxiliary sensor.

13. An apparatus as in claim 9 where the estimating of the deflection is based, at least partially, upon location information from at least one sensor regarding at least one of:
a portion of the robot, and
the substrate carried by the robot.

14. An apparatus as in claim 9 where the adjusting of movement of the robot is further based upon forward kinematics determination of the end effector which subsequently provides modified estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

15. An apparatus as in claim 9 where the adjusting of the movement of the robot comprises providing the estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

16. An apparatus as in claim 9 where the estimated end effector coordinates are provided to a robot location sensing system and/or to a substrate location sensing system, which subsequently provides modified estimated end effector coordinates to the adaptive placement system to determine adjusted end effector coordinates to be used to drive at least one motor of the robot.

17. A non-transitory program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine for performing operations, the operations comprising:
calculating model end effector coordinates of an end effector of a robot when at least one

Assignees

• Persimmon Technologies Corp
• Persimmon Tech Corporation

Inventors

• Hosek Martin
• Lipcon Jacob

Classifications

• B25J9/1638 Primary

  compensation for arm bending/inertia, pay load weight/inertia · CPC title

• G05B2219/39176

  Compensation deflection arm · CPC title

• B25J9/104

  with cables, chains or ribbons · CPC title

• Y10S901/09

  Closed loop, sensor feedback controls arm movement · CPC title

• Y10S901/02

  Arm motion controller · CPC title