Recognition Method for Testing Manipulator Trajectory Change-point

doi:10.3901/JME.2020.18.015

Abstract

Abstract: A six-axis manipulator is used in ultrasonic nondestructive testing technology to realize automatic testing, which is an important development direction in the field of testing automation. In ultrasonic testing, the principle of smooth motion is followed. Sudden change in the speed of the manipulator is occurred due to large change in posture in the detection trajectory, and testing results is affected by poor coupling. To solve the above problems, a change-point detection method based on the matrix information geometry of special Euclidean group is proposed. Once a change-point occurs, the distance between the current point and the Riemannian mean of its neighbor points should be a local maximum. According to this principle, the change-points of the trajectory are identified in advance, and then the velocity is smoothed near these change-points. The effectiveness of the Riemannian mean method is verified by the inverse kinematics solution method of six-axis manipulator. Furthermore, the manipulator platform movement experiment is carried out to identify the change-points and reduce its speed near the change-points, so that the detection movement of each axis of the manipulator is more stable.

Key words: six-axis manipulator, change-point recognition, information geometry, Riemannian mean

CLC Number:

TB553

ZHAO Xinyu, WEN Xin, DUAN Xiaomin. Recognition Method for Testing Manipulator Trajectory Change-point[J]. Journal of Mechanical Engineering, 2020, 56(18): 15-21.

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