In order to improve the positioning accuracy of the six-axis robot

the manta ray optimization algorithm(MROA)is optimized to make it suitable for kinematic parameter errors identification of the robot.Firstly

the modified D-H(MD-H) method is used to derive the robot error model

and the redundant parameters in 25 parameters are removed and dimensionally reduced to a 10-parameter model

so as to improve the parameter error identification speed of the algorithm.Secondly

the identification of robot kinematic parameters is transformed into a nonlinear optimization problem

and the original MROA is improved by using self-tuning parameter control strategy and survival of the fittest strategy

to improve the identification precision of kinematic parameter errors.Finally

MROA and least square method are used to identify and compensate the geometric parameter errors and test the absolute positioning accuracy.The experimental results are as follows:The positioning error of the robot measured by the laser tracker is 5.9287mm before compensation

positioning error of robot is 0.2876mm after the least square method identification and compensation

and positioning error of robot is 0.1481mm after the MROA identification and compensation

the error is significantly reduced.Moreover

the positioning accuracy of the MROA is 44.31% higher than that of the least square method

indicating the effectiveness of the proposed method.