Modeling, control and gait design of a quadruped robot with active spine towards energy efficiency

Obtaining the dynamical model of a system with high degrees of freedom (DOF) is an extremely tedious and error-prone task. On the other hand, designing suitable and energy efficient gaits for legged robots is a difficult procedure due to the large number of parameters that require tuning and calibration. In this paper we obtain the equations of motion for a quadruped robot with 12 DOF and active spine in sagittal plane. Later, we address the problem of gait implementation and optimization. We propose an evolutionary approach towards fining the optimal trajectory to minimize energy requirements. We present a nonlinear control methodology to achieve exponential stability of the gait. The results of simulations show that the method successfully reduced energy consumption of the system compared to traditional hand-tuned approaches.