US 12,314,051 B2
Method for navigating root through limited space, robot and computer-readable storage medium
Dunhao Liu, Shenzhen (CN); Youjun Xiong, Shenzhen (CN); and Huan Tan, Shenzhen (CN)
Assigned to UBTECH ROBOTICS CORP LTD, Shenzhen (CN)
Filed by UBTECH ROBOTICS CORP LTD, Shenzhen (CN)
Filed on Dec. 12, 2022, as Appl. No. 18/079,807.
Claims priority of application No. 202210177915.4 (CN), filed on Feb. 24, 2022.
Prior Publication US 2023/0266763 A1, Aug. 24, 2023
Int. Cl. G05D 1/00 (2024.01); G01C 21/20 (2006.01)
CPC G05D 1/0214 (2013.01) [G01C 21/20 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A computer-implemented method for navigating a robot through a limited space, the method comprising:
obtaining a planned first path for the robot to reach a target position;
calculating curvature and/or normal vectors of points in the first path;
according to the curvature and a preset curvature threshold, and/or according to the normal vectors and a preset normal vector change threshold, obtaining a first straight path for the robot outside the limited space by curve fitting;
determining an intersection of a centerline of the limited space and the first straight path, and determining a second straight path for the robot to move through the limited space according to the centerline and the intersection; and
generating a second path for the robot to move through the limited space based on the first straight path and the second straight path, and navigating the robot to move through the limited space according to the second path;
wherein obtaining the first straight path for the robot outside the limited space by curve fitting according to the curvature and a preset curvature threshold, comprises:
comparing the curvature of each of the points in the first path with the preset curvature threshold, and determining ones of the points in the first path whose curvature is less than the curvature threshold; and
obtaining the first straight path by performing straight line fitting on points before entering the limited space and whose curvature is less than the curvature threshold; and/or
wherein obtaining the first straight path for the robot outside the limited space by curve fitting according to the normal vectors and a preset normal vector change threshold, comprises:
determining normal vector change values according to pairs of two adjacent points in the first path;
comparing each of the normal vector change values with the preset normal vector change threshold, and determining ones of the normal vector change values smaller than the normal vector change threshold; and
obtaining the first straight path by performing straight line fitting on points corresponding to the normal vector change values smaller than the normal vector change threshold.