Modeling and optimal control of rescue quadruped robot with high payload

Abstract

Timely and efficient rescue missions in nuclear power plant accidents require operating robots to work under high payload typically more than 300 lb. Dynamics of the high payload quadruped robots driven by hydraulic cylinder with parallel designed legs are typically studied by commercial software due to its complexity to establish proper models. This paper proposes a kinematics model and an approximate dynamics model to describe the velocity and the force of the hydraulic cylinder, which are then used to characterize the energy requirement for rescuing walking performance. Furthermore, the models are used to optimally design the step length and height in robot rescue mission that balances the trade off between the energy consumption in robotic motion due to limited battery capacity and the requirement for timely rescuing. We applied Nelder-Mead algorithm to solve for the optimal pair of length and height.