Design and control method of a hydraulic power unit for a wheel-legged robot

For a hydraulic wheel-legged robot (WLR), it is essential to have a powerful and lightweight power supply. In this paper, a compact hydraulic power unit (HPU) is developed, and a control method to reduce the energy consumption of the robot is proposed. To achieve a high jump of the robot, an accumulator serves as an auxiliary oil source. To reduce the pressure loss caused by the throttle of the servo valve, we control the pressure of the system through load sensing. Simulation results showed that the power of the HPU using the accumulator could be amplified 3.3 times. The experimental results obtained through physical testing showed that the power consumption of the system using the load sensing mechanism was reduced by more than 50 %.

Automated summary

In this paper, a compact hydraulic power unit (HPU) is developed, and a control method to reduce the energy consumption of the robot is proposed. By using an accumulator and load sensing mechanism, the robot's jumping ability is improved and energy consumption is reduced.