Three degree-of-freedom robotic systems for automatic and/or collaborative planar fastening operations

Patent metadata

Field	Value
Publication number	US-11931892-B2
Application number	US-202117554161-A
Country	US
Kind code	B2
Filing date	Dec 17, 2021
Priority date	Nov 17, 2021
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

A robotic system includes a support structure, a motor mount assembly, first and second parallel chains, a serial translation assembly, a sensor and a control module. The motor mount assembly includes rotary motors, where the rotary motors include a first rotary motor and a second rotary motor. The first and second parallel chains are connected to the movable platform, the rotary motors and the motor mount assembly. The serial translation assembly is connected to the supporting structure and the motor mount assembly and includes a linear actuator and a third rotary motor. The sensor is connected to the movable platform and detects force applied by a human operator on the movable platform and generates a signal indicative of the force applied. The control module controls the rotary motors and the third rotary motor based on the signal to assist the human operator in moving the movable platform.

First claim

What is claimed is:

1. A robotic system comprising:
a support structure;
a movable platform;
a motor mount assembly comprising a plurality of rotary motors, wherein the plurality of rotary motors comprise a first rotary motor and a second rotary motor;
a first plurality of parallel chains connected to the movable platform, the first rotary motor, and the motor mount assembly;
a second plurality of parallel chains connected to the movable platform, the second rotary motor, and the motor mount assembly;
a serial translation assembly connected to the supporting structure and the motor mount assembly and comprising a linear actuator and a third rotary motor;
a sensor connected to the movable platform and configured to detect force applied by a human operator on the movable platform and generate a signal indicative of the force applied; and
a control module configured to control the plurality of rotary motors and the third rotary motor based on the signal to assist the human operator in moving the movable platform relative to the supporting structure.

2. The robotic system of claim 1 , wherein:
the first plurality of parallel chains comprises a first chain and a second chain;
the first chain extends parallel to the second chain;
the second plurality of parallel chains comprises a third chain and a fourth chain; and
the third chain extends parallel to the fourth chain.

3. The robotic system of claim 1 , wherein:
the first plurality of parallel chains comprises a first chain;
the first chain is connected to a first motor of the motor mount assembly and to a plate of the motor mount assembly;
the second plurality of parallel chains comprises a second chain; and
the second chain is connected to a second motor of the motor mount assembly and to the plate of the motor mount assembly.

4. The robotic system of claim 1 , the first plurality of parallel chains comprises:
an upper outer chain; and
a lower inner chain disposed inward and below the upper outer chain.

5. The robotic system of claim 4 , wherein the lower inner chain comprises two parallel extending chains.

6. The robotic system of claim 1 , wherein the first plurality of parallel chains comprises:
a first chain comprising three joints, a link, two bars and a fork; and
a second chain comprising five joints and three bars.

7. The robotic system of claim 1 , wherein the first plurality of parallel chains comprises:
a first chain comprising a first plurality of revolute joints; and
a second chain comprising a second plurality of revolute joints.

8. The robotic system of claim 1 , the first plurality of parallel chains and the second plurality of parallel chains provide a two parallelogram-shaped arrangements.

9. The robotic system of claim 1 , wherein the first plurality of parallel chains, the second plurality of parallel chains, the motor mount assembly and the serial translation assembly provide three degrees-of-freedom motion for the movable platform.

10. The robotic system of claim 1 , further comprising a fastening tool attached to at least one of the movable platform and the sensor.

11. The robotic system of claim 1 , wherein the linear actuator comprises:
a belt;
a first plurality of guide rails;
a mounting block slidable on the first plurality of guide rails and connected to the motor mount assembly and the belt;
a second plurality of guide rails; and
a counterbalance weight slidable on the second plurality of guide rails and connected to the belt.

12. A robotic system comprising:
a support structure;
a movable platform;
a motor mount assembly comprising a plurality of rotary motors, wherein the plurality of rotary motors comprise a first rotary motor and a second rotary motor;
a plurality of parallel chain sets are connected to the movable platform, the plurality of rotary motors, and the motor mount assembly and provide a parallelogram-shaped arrangement;
a serial translation assembly connected to the supporting structure and the motor mount assembly and comprising a linear actuator and a third rotary motor, where the linear actuator moves the plurality of parallel chain sets based on output of the third rotary motor; and
a control module configured to control the plurality of rotary motors and the third rotary motor to provide three degrees-of-freedom motion of the movable platform relative to the supporting structure.

13. The robotic system of claim 12 , wherein the plurality of parallel chain sets comprise:
a first upper outer chain;
a second upper outer chain providing a first parallelogram-arrangement with the first upper outer chain;
a first lower inner chain; and
a second lower inner chain providing a second parallelogram-arrangement with the first lower inner chain.

14. The robotic system of claim 13 , wherein each of the first upper outer chain, the second upper outer chain, the first lower inner chain and the second lower inner chain include a plurality of joints and a plurality of bars connected serially.

15. The robotic system of claim 13 , wherein:
the first upper outer chain extends parallel to the first lower inner chain; and
the second upper outer chain extends parallel to the second lower inner chain.

16. The robotic system of claim 13 , wherein:
the first lower inner chain comprises two chains; and
the second lower inner chain comprises two chains.

17. The robotic system of claim 12 , further comprising a sensor connected to the movable platform and configured to detect force applied by a human operator on the movable platform and generate a signal indicative of the force applied,
wherein the control module is configured to control operation of the plurality of rotary motors and the third rotary motor to assist the human operator in movement of the movable platform.

18. The robotic system of claim 12 , wherein the plurality of parallel chain sets are configured to move parallel to a plane.

19. The robotic system of claim 12 , wherein the plurality of parallel chain sets provide:
a first loop for translation of the movable platform; and
a second loop to compensate for torque exerted on the movable platform.

20. The robotic system of claim 12 , wherein the linear actuator comprises:
a belt;
a first plurality of guide rails;
a mounting block slidable on the first plurality of guide rails and connected to the motor mount assembly and the belt;
a second plurality of guide rails; and
a counterbalance weight slidable on the second plurality of guide rails and connected to the belt.

Assignees

• Gm Global Tech Operations Llc
• Univ Shanghai Jiaotong

Inventors

• Sun Qiao
• Chen Xianbao
• Sun Jing
• Gao Feng
• Gao Dalong
• Huang Ningjian

Classifications

• B25J9/0081 Primary

  with leader teach-in means · CPC title

• B25J9/0009

  Constructional details, e.g. manipulator supports, bases · CPC title

• B25J9/0045

  with kinematics chains having a rotary joint at the base · CPC title

• B25J9/1633

  compliant, force, torque control, e.g. combined with position control · CPC title

• B25J13/085 Primary

  Force or torque sensors (B25J13/082, B25J13/084 take precedence) · CPC title