This paper present a method for detecting collision occurs in the robot manipulator and reacting according to collision direction. An experiment was conducted to read the joints speed during collision of the UR3 robot at static position, where the joints speeds are supposed to be zero. The experiment showed that when collision occurs within the manipulator there is oscillatory speed produced in joints, which is suggested to be duo to the stiffness of the harmonic drive. The harmonic drive is a flexible transmission generates stiffness behavior, as a spring, between the motor and the link. The collision is determined from the oscillatory speed produced in robot joints at static position. The method successfully identified the collision impact at joints, and reacted according to the collision direction. The experimental setup and the results are presented in this paper.
Omar Abdelaziz and Minzhou Luo Serial Robot Collision Reaction using Joints Data at Stationary Position International Journal of Engineering Works Vol. 7 Issue 10 PP. 356-360 October 2020 https://doi.org/10.34259/ijew.20.710356360.
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