Abstract:ydraulic manipulator has the disadvantage of low energy efficiency in the process of realizing closed-loop motion control because of using hydraulic system as the driving device. To solve this problem, an energy saving control method based on global energy optimization was proposed. The motion transformation between the joint of the hydraulic manipulator and the driving hydraulic cylinder was analyzed, and the nonlinear mapping relationship between the joint motion and the pressure of the two chambers of the hydraulic cylinder was deduced. On this basis, the energy consumption function of the hydraulic manipulator was constructed to form a multi-objective optimization problem with the motion time, and the improved NSGA-Ⅱ multi-objective optimization algorithm was used to solve the optimal solution. By comparing the simulation results, it can be found that the proposed energy-saving control method saves 46.73% energy compared with the traditional constant-supply pressure control method, and the energy is saved by 8.62% compared with the traditional time-energy optimization strategy, verifying the effectiveness of the proposed method.