Affiliations: [a] College of Locomotive and Rolling Stock Engineering, Dalian Jiaotong University, Dalian, China
| [b] CRRC Qingdao Sifang Locomotive & Rolling Stock Co., Ltd., Qingdao, China
Correspondence:
[*]
Corresponding author. Xiaodong Liu, College of Locomotive and Rolling Stock Engineering, Dalian Jiaotong University, 110618, Dalian, China. E-mail: lxd_djtu@126.com.
Abstract: In the process of visual sorting, in order to solve the problem that the irregular contour target position is difficult to locate quickly and accurately, and it is difficult to realize the self-defined grab point, a method of target pose detection based on the contour center of gravity edge distance vector and local polar coordinates is proposed. Firstly, the target contour is determined by adaptive edge detection and the comparison of contour moments, and the larger distance direction from the contour center of gravity to the smallest outer rectangle is defined as the direction from the contour center of gravity to the edge distance vector. The deflection angle of the target is determined by the vector direction and the position of the outer rectangle to detect the deflection angle of the irregular workpiece. On this basis, judge whether the designated point is the relative center of gravity in the local polar coordinate system, and realize the intelligent positioning of the set point on the target by detecting the coordinates of the designated point in the center of gravity positioning. The experimental results show that the method is suitable for complex contour targets, and the positioning results are accurate and the positioning time is short, so it has high engineering application value.
Keywords: Edge distance vector, declination detection, attitude detection, relative
center, contour recognition, fixed point positioning
