关键词: 强化学习, 机器人柔顺控制, 轴孔装配, 导纳控制器

Abstract: To solve the problem of uncertain pose (position and pose) of peg and hole for improving the success rate,efficiency,and generalization ability of robot assembly operation,a variable admittance control strategy based on SARSA algorithm was proposed.The mechanism of peg-in-hole assembly was analyzed to guide the design of motion control strategy.Then,the different admittance parameters were analyzed by a series of simulations to obtain the controller parameters.In addition,an action evaluation method combining the displacement in each step and insertion depth was established to solve the problem of complex reward establishment in the assembly process.Meanwhile,qualification trace function is introduced to enhance learning efficiency of SARSA algorithm.Three sets of assembly experiments were implemented on the real robot.The improvement of success rate and efficiency could be verified by position and admittance control experiments.The performance of generalization ability was also validated through experiments in different initial pose.The results indicated that the proposed algorithm could solve the problem of the uncertain pose of peg and hole in the assembly task.

Key words: reinforcement learning, robot compliance control, peg-in-hole assembly, admittance controller