Spring parameters design to increase the loading capability of a hydraulic quadruped robot

A quadruped robot “Baby Elephant” with parallel legs has been developed. It is about 1 m tall, 1.2 m long and 0.5m wide. It weighs about 130 kg. Driven by a new type of hydraulic actuation system, the Baby Elephant is designed to work as a mechanical carrier. It can carry a payload more than 50 kg. In this study, the structure of the legs is introduced first. Then the effect of the springs for increasing the loading capability is explained and discovered. The design problem of the spring parameters is also discussed. Finally, simulations and experiments are carried out to confirm the effect.