Energy efficiency onboard hydraulic power for quadruped robot based on high-low double pumps supply

This work presents a high energy efficiency onboard hydraulic system for quadruped robot. Firstly, based on the rhythmic motion and mechanical characteristics of leg joints, the energy supply mode that supplies low-pressure oil and high-pressure oil separately for the swing phase and supporting phase is used, and the switch between different oil circuits for each legs is implemented by two digital on-off valves. What's more, to obtain the pressure dynamics characteristics and energy consumption model, the mathematical models is deduced, and the analysis results illustrates that a better rate response can be achieved by adjusting time offset reasonable properly. Finally, the simulations and experiments are conducted to prove that the proposed system shows better energy efficiency compared with that of single pump supply pressure system, meanwhile, the fast dynamic response and the high tracking accuracy are also maintained.