Robot and method of controlling the same

Patent metadata

Field	Value
Publication number	US-2023278195-A1
Application number	US-202318173342-A
Country	US
Kind code	A1
Filing date	Feb 23, 2023
Priority date	Mar 4, 2022
Publication date	Sep 7, 2023
Grant date	—

Abstract

A robot includes a robot hand, a robot arm, a force sensor, and a control device. The control device performs admittance control to determine a position of the robot hand in accordance with a force detected by the force sensor, and provides, to the robot arm, an instruction to move the robot hand to the determined position. Further, the control device records, as teaching data, the instruction provided to the robot arm.

First claim

1 . A robot comprising:
a robot arm; a robot hand attached to the robot hand; a force sensor configured to detect a force acting on the robot hand; and a control device that performs admittance control to determine a position of the robot hand in accordance with the force detected by the force sensor, provides, to the robot arm, an instruction to move the robot hand to the determined position, and records, as teaching data, the instruction provided to the robot arm.

2 . The robot according to claim 1 , further comprising a manipulating device,
wherein the control device operating in a first operation mode performs admittance control to determine positions in three directions of the robot hand in accordance with forces in the three directions detected by the force sensor, and wherein the control device operating in a second operation mode performs admittance control to determine positions in two directions of the robot hand in accordance with forces in the two directions detected by the force sensor, and performs velocity control to determine a position in the remaining one direction of the robot hand in accordance with a manipulated variable inputted into the manipulating device.

3 . The robot according to claim 2 , wherein the control device operating in the first operation mode determines positions x, y, and z of the robot hand by solving an equation of motion including forces F x , F y , and F z detected by the force sensor and force sensitivities α x , α y , and α z .

4 . The robot according to claim 3 , wherein the equation of motion is the following formulas (1):

x
″

=

-

c
x

m
x

⁢

x
′

+

a
x

m
x

⁢

F
x

(
1
)

y
″

=

-

c
y

m
y

⁢

x
′

+

a
y

m
y

⁢

F
y

z
″

=

-

c
z

m
z

⁢

x
′

+

a
z

m
z

⁢

F
z

wherein each of m x , m y , and m z is a constant representing a virtual mass, and each of c x , c y , and c z is a constant representing a virtual coefficient of viscosity.

5 . The robot according to claim 2 , wherein the control device operating in the second operation mode determines positions x and y of the robot hand by solving a first equation of motion including forces F x and F y detected by the force sensor and force sensitivities α x , α y , and α z , and determines position z of the robot hand by solving a second equation of motion including manipulated variable θ inputted into the manipulating device.

6 . The robot according to claim 5 , wherein the first equation of motion is the following formulas (2a), and the second equation of motion is the following formula (2b):

x
″

=

-

c
x

m
x

⁢

x
′

+

a
x

m
x

⁢

F
x

(

2
⁢
a

)

y

Assignees

• Sintokogio Ltd
• Univ Yamanashi

Inventors

• Tanaami Yoshikane
• Hayashi Miyuki
• Noda Yoshiyuki

Classifications

• B25J9/1633 Primary

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

• G05B2219/39529

  Force, torque sensor in wrist, end effector · CPC title

• B25J9/1687

  Assembly, peg and hole, palletising, straight line, weaving pattern movement · CPC title

• G05B19/423

  Teaching successive positions by walk-through, i.e. the tool head or end effector being grasped and guided directly, with or without servo-assistance, to follow a path · CPC title

• G05B2219/39319

  Force control, force as reference, active compliance · CPC title