In order to improve the trajectory control accuracy of industrial robot,a motion error observation control strategy was proposed.The structure of the robot was analyzed and its working principle was clarified.The coordinate system of the industrial robot was established,and the transformation matrix of the coordinate system between the robot connecting rods was obtained.Using the transformation matrix of the coordinate system between the connecting rods,the kinematic model of the robot end effector was obtained.Finally,based on the measured motion error of the robot and the nominal forward kinematics model of the industrial robot,the transformation model between the sensor frame and the nominal frame and the base was obtained.Through the transformation model,the position vector between the sensor frame and the nominal frame and the rotation matrix of the dynamic error transformation were calculated,and the measured motion error value was obtained.By measuring the motion error value,a motion error observer was constructed to obtain the estimated motion error of the robot,and the estimated motion error was combined with the neural network controller to realize the accurate control of the robot trajectory.The experimental results show that the proposed method can be used to accurately track the planar and spatial calibration trajectories,and the tracking accuracy of the proposed method is improved by 34.25% compared with the sliding mode control strategy.It shows that this method can be used to accurately control the motion trajectory of industrial robot.