Industrial robot high precision peg-in-hole assembly based on hybrid force/position control
WU Bing-long1,2, QU Dao-kui1, XU Fang1
1. Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China
A peg-in-hole assembly strategy and a new implementation of hybrid force/position control strategy were proposed, in order to analyze the application of industrial robot in high precision assembly field and solve the typical peg-in-hole problem in high precision assembly. The assembly process included three stages:search, insert and complete. The proposed hybrid force/position control system was based on the motors velocity control loop, and had a larger system bandwidth compared to the traditional force control system based on position control loop. The control structure was simple and easy to implement, and could integrate the velocity signal, and transform into implementation based on the motors position control loop. The simulation and experiment were conducted to verify the effectiveness of the method. The simulation results show that the force/position hybrid control method based on the velocity control loop has better performance to track higher frequency sinusoidal signal than traditional method which is based on the position control loop. The industrial robot was used to assembly the reducer of robot arm. Experimental results show that the force/position hybrid control method with spiral search hole strategy can find the assembly hole and finish the peg-in-hole assembly task well.
Received: 04 December 2016
Published: 09 March 2018
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