Six degree-of-freedom and three degree-of-freedom robotic systems for automatic and/or collaborative fastening operations

Patent metadata

Field	Value
Publication number	US-11813743-B2
Application number	US-202117554549-A
Country	US
Kind code	B2
Filing date	Dec 17, 2021
Priority date	Nov 17, 2021
Publication date	Nov 14, 2023
Grant date	Nov 14, 2023

Abstract

A robotic system includes a support structure, a platform, a center serial chain, outer serial chains, motors, a sensor, and a control module. The center serial chain connects a center of the platform to the support structure and includes first joints connected to a linear sliding shaft. The outer serial chains are disposed radially outward of the center serial chain. Each of the outer serial chains includes second joints connecting a bar to the platform and the supporting structure. The motors are connected to the outer serial chains. The sensor is connected to the platform and detects at least one of force or torque applied by a human operator on the platform and generates a signal indicative thereof. The control module controls the motors based on the signal to assist the human operator in at least one of moving or rotating the platform.

First claim

What is claimed is:

1. A robotic system comprising:
a support structure;
a movable platform;
a center serial chain connecting directly or indirectly a center of the movable platform to the support structure and comprising a first plurality of joints connected directly or indirectly to a linear sliding shaft;
a plurality of outer serial chains disposed radially outward of the center serial chain, wherein each of the plurality of outer serial chains comprises a second plurality of joints connecting a bar directly or indirectly to the movable platform and the supporting structure;
a plurality of motors connected to the plurality of outer serial chains;
a sensor connected to the movable platform and configured to detect at least one of force or torque applied by a human operator on the movable platforms and generate a signal indicative of the at least one of force or torque applied; and
a control module configured to control the plurality of motors based on the signal to assist the human operator in at least one of moving or rotating the movable platform.

2. The robotic system of claim 1 , wherein:
the plurality of outer serial chains comprise three pairs of outer serial chains; and
each pair of outer serial chains comprises two outer serial chains.

3. The robotic system of claim 1 , wherein the plurality of outer serial chains comprises six outer serial chains.

4. The robotic system of claim 1 , wherein:
the second plurality of joints of each of the plurality of outer serial chains comprises a first joint and a second joint;
the first joint of each of the plurality of outer serial chains is a universal joint; and
the second joint of each of the plurality of outer serial chains is a spherical joint.

5. The robotic system of claim 4 , wherein:
the plurality of outer serial chains comprise three pairs of chains; and
the control module is configured to independently actuate each of the plurality of outer serial chains.

6. The robotic system of claim 5 , further comprising a plurality of linear sliders, wherein:
the plurality of outer serial chains comprise three pairs of chains; and
each of the three pairs of chains is connected to a respective one of the plurality of linear sliders.

7. The robotic system of claim 1 , wherein:
the first plurality of joints of the center serial chain comprise a first in and a second joint; and
the first joint and the second joint are universal joints.

8. The robotic system of claim 7 , wherein:
a drive fork of the first joint is in alignment with a drive fork of the second joint; and
a driven fork of the first joint is in alignment with a driven fork of the second joint.

9. The robotic system of claim 1 , wherein the plurality of outer serial chains and the center serial chain provide three degrees-of-freedom motion for the movable platform or six degrees-of-freedom motion for the movable platform.

10. The robotic system of claim 1 , wherein the plurality of outer serial chains comprise:
a first outer serial chain;
a second outer serial chain disposed 120° of separation azimuthally from the first outer serial chain relative to a center line extending through the center serial chain; and
a third outer serial chain disposed 120° of separation azimuthally from the first outer serial chain and the second outer serial chain relative to the center line extending through the center serial chain.

11. The robotic system of claim 1 , wherein the plurality of outer serial chains comprise:
a first outer serial chain;
a second outer serial chain disposed 90° of separation azimuthally from the first outer serial chain relative to a center line extending through the center serial chain; and
a third outer serial chain disposed 180° of separation azimuthally from the first outer serial chain and the second outer serial chain relative to the center line extending through the center serial chain.

12. The robotic system of claim 1 , further comprising:
a fastening tool; and
a bearing disposed between the movable platform and the fastening tool.

13. A robotic system comprising:
a support structure;
a movable platform;
a universal-prismatic-universal serial chain directly or indirectly connecting a center of the movable platform to the support structure;
a plurality of outer serial chains disposed radially outward of the universal-prismatic-universal serial chain, wherein each of the plurality of outer serial chains is a prismatic-universal-spherical serial chain, and wherein each of the plurality of outer serial chains connects the movable platform to the support structure;
a plurality of motors connected to the plurality of outer serial chains;
a sensor connected to the movable platform and configured to detect at least one of force or torque applied by a human operator on the movable platform and generate a signal indicative of the at least one of force or torque applied; and
a control module configured to control the plurality of motors based on the signal to assist the human operator in at least one of moving or rotating the movable platform.

14. The robotic system of claim 13 , wherein the universal-prismatic-universal serial chain comprises a first universal joint, a linear sliding shaft, and a second universal joint.

15. The robotic system of claim 13 , wherein each of the plurality of outer serial chains comprise a linear slider, a universal joint, a bar and a spherical joint.

16. A robotic system comprising:
a support structure;
a movable platform;
a universal-prismatic-universal serial chain directly or indirectly connecting a center of the movable platform to the support structure;
a plurality of revolute-universal-spherical serial chains disposed radially outward of the universal-prismatic-universal serial chain, wherein each of the plurality of revolute-universal-spherical serial chains connects the movable platform to the support structure;
a plurality of motors connected to the plurality of revolute-universal-spherical serial chains;
a sensor connected to the movable platform and configured to detect at least one of force or torque applied by a human operator on the movable platform and generate a signal indicative of the at least one of force or torque applied; and
a control module configured to control the plurality of motors based on the signal to assist the human operator in at least one of moving or rotating the movable platform.

17. The robotic system of claim 16 , wherein the universal-prismatic-universal serial chain comprises a first universal joint, a linear sliding shaft, and a second universal joint.

18. The robotic system of claim 16 , wherein each of the plurality of revolute-universal-spherical serial chains comprise a revolute joint, a first bar, a universal joint, a second bar and a spherical joint.

19. The robotic system of claim 1 , wherein:
an end of the center serial chain that is connected to the support structure is not connected to a motor; and
the control module is configured to control the plurality of motors for six degrees-of-freedom motion of the movable platform.

20. The robotic system of claim 1 , wherein:
the plurality of motors include six motors for independent actuation of six outer serial chains; and
the plurality of outer serial chains comprise the six outer serial chains.

Assignees

• Gm Global Tech Operations Llc
• Univ Shanghai Jiaotong

Inventors

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

Classifications

• B25J9/0072 Primary

  of the hybrid type, i.e. having different kinematics chains · CPC title

• B25J9/106

  with articulated links · CPC title

• B25J11/005

  Manipulators for mechanical processing tasks · CPC title

• B25J13/085 Primary

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

• B25J17/0216

  comprising a stewart mechanism · CPC title