Walking control method, biped robot and computer-readable storage medium

Patent metadata

Field	Value
Publication number	US-12311545-B2
Application number	US-202218090457-A
Country	US
Kind code	B2
Filing date	Dec 28, 2022
Priority date	Mar 22, 2021
Publication date	May 27, 2025
Grant date	May 27, 2025

Abstract

A walking control method for a biped robot includes: detecting whether the biped robot is in an unbalanced state; in response to detection that the biped robot is in the unbalanced state, obtaining a predicted balance step length corresponding to the biped robot in the unbalanced state; performing a smooth transition processing on the predicted balance step length according to a current movement step length of the biped robot to obtain a desired balance step length corresponding to the predicted balance step length; determining a planned leg trajectory of the biped robot according to the desired balance step length; and controlling a current swing leg of the biped robot to move according to the planned leg trajectory.

First claim

What is claimed is:

1. A computer-implemented walking control method for a biped robot, comprising:
detecting whether the biped robot is in an unbalanced state;
in response to detection that the biped robot is in the unbalanced state, obtaining a predicted balance step length corresponding to the biped robot in the unbalanced state;
performing a smooth transition processing on the predicted balance step length according to a current movement step length of the biped robot to obtain a desired balance step length corresponding to the predicted balance step length;
determining a planned leg trajectory of the biped robot according to the desired balance step length; and
controlling a current swing leg of the biped robot to move according to the planned leg trajectory.

2. The method of claim 1 , wherein the current movement step length comprises planned step lengths of the biped robot in a pitch direction and a roll direction relative to a horizontal plane respectively, the predicted balance step length comprises estimated step lengths of the biped robot in the pitch direction and the roll direction relative to the horizontal plane respectively, the desired balance step length comprises to-be-realized step lengths of the biped robot in the pitch direction and the roll direction relative to the horizontal plane respectively, the planned step length, the estimated step length, and the to-be-realized step length of the biped robot in the pitch direction corresponds to one another, and the planned step length, the estimated step length, and the to-be-realized step length of the biped robot in the roll direction corresponds to one another;
wherein performing the smooth transition process on the predicted balance step length according to the current movement step length of the biped robot to obtain the desired balance step length corresponding to the predicted balance step length, comprises:
for each planned step length included in the movement step length, calculating a step length difference between the planned step length and the estimated step length corresponding to the planned step length;
calculating a desired acceleration matching the corresponding estimated step length according to the step length difference, a current walking speed corresponding to a moving direction to which the planned step length belongs, a preset position influence coefficient, and a preset speed influence coefficient, wherein the preset position influence coefficient represents an influence weight value of the corresponding step length difference in a smoothing process of the estimated step length, and the preset speed influence coefficient represents an influence weight value corresponding to the current walking speed in the smoothing process of the estimated step length;
calculating a desired walking speed matching the corresponding estimated step length according to current walking speed, the desired acceleration and a step control frame duration of the biped robot; and
calculating the current to-be-realized step length corresponding to the corresponding estimated step length of the biped robot according to the planned step length, the desired walking speed and the step control frame duration.

3. The method of claim 2 , wherein the planned leg trajectory is expressed by the following equations:

{

X
L

=

L
x

2

-

L
x

2

⁢

cos
⁡
(

π
⁢
t
/
T

)

Y
L

=

L
y

2

-

L
y

2

⁢

cos
⁡
(

π
⁢
t
/
T

)

Z
L

=

at
3

+

bt
2

+
ct
+
d

,

where X L represents a projected position of the planned leg trajectory relative to the horizontal plane in the pitch direction, Y L represents a projected position of the planned leg trajectory relative to the horizontal plane in the roll direction, Z L represent a leg position of the planned leg trajectory in a vertical direction, L x represents the to-be-realized step length of the biped robot in the pitch direction relative to the horizontal plane, L y represents the to-be-realized step length of the biped robot in the roll direction relative to the horizontal plane, T represents a gait cycle of the biped robot, t represents a movement moment of the biped robot, and a, b, c and d represents preset leg-lift height coefficients of the biped robot.

4. The method of claim 1 , wherein controlling the current swing leg of the biped robot to move according to the planned leg trajectory comprises:
determining a desired position of a leg end corresponding to a current mom

Assignees

• Ubtech Robotics Corp Ltd

Inventors

• Chen Chunyu
• Bai Jie
• Liu Yizhang
• Ge Ligang
• Xie Zheng
• Xiong Youjun

Classifications

• B62D57/032 Primary

  with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid (B62D57/024 takes precedence) · CPC title

• B25J9/1602 Primary

  characterised by the control system, structure, architecture · CPC title

• G05D1/0223 Primary

  involving speed control of the vehicle (vehicle fittings for automatically controlling, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator B60K31/00) · CPC title