With the increasing demand for robot control accuracy in fields such as industrial automation, logistics handling, and medical assistance, ensuring the precision of motion control has become crucial; This study investigated the high-precision motion control of a four-wheel robot and optimized the depth deterministic strategy gradient algorithm using an immediate reward priority mechanism and a time difference error priority mechanism; A high-precision system with two proportional integral derivative controllers has been innovatively designed. On the basis of building a chassis kinematic model, independent PID controllers were designed for the x and y directions, and optimization algorithms were used to adaptively adjust the parameters of the controllers; After experimental testing, the tracking error controlled by the x-direction optimization algorithm is 0.0976 m, which is 9.76% lower than the algorithm error before optimization; The tracking error of the y-direction optimization algorithm is 0.1088 m, and the error of the optimization algorithm is reduced by about 48.0% compared to the proportional integral derivative controller; The designed control system meets the practical application of robot motion control engineering, with steady-state error and dynamic error of 0.02 and 0.05, respectively; The system has small errors, high control accuracy, and is suitable for fine control tasks, providing new technical ideas for the field of high-precision motion control of robots.