Digital hydraulic circuits control hydraulic flow rate and pressure by switching a control valve at a high-frequency PWM signal and have the advantage of energy efficiency. A flow booster and a pressure booster are typical examples of the digital hydraulic circuit and both of them have been studied. In this paper, a flow booster model with a feedback controller and a pressure booster model with a feedforward controller are applied to a simple double-rod cylinder model considering only inertia-load. As a result of simulation study, the system achieves both cylinder drive by flow booster and energy accumulation by pressure booster simultaneously. But it is worth mentioning that there are technical issues such as response delay due to accumulator dynamics and excessive oil supply when driving at a constant speed. Additional control schemes to solve the issues and application to more realistic systems are future research works.
MAESHIMA et al. (Wed,) studied this question.