Simplified power consumption modeling and identification for wheeled skid-steer robotic vehicles on hard horizontal ground

Autonomous mobile robots have limited energy sources. This work studies power consumption of the locomotion system of wheeled skid-steer vehicles on hard horizontal terrain at walking speeds. This issue is very important for this kind of vehicles due to relevant power losses associated to dynamic friction during turnings. The paper adopts a kinematics approach to provide a simplified power model. This static model estimates motor power consumption as a function of the left- and right-side wheels' speeds. The model is defined through three constant parameters: the x-coordinate of the treads' instantaneous center of rotation on the ground plane, a traction resistance constant, and the ground-wheel friction coefficient. Furthermore, a simple experimental identification procedure is proposed to obtain the model parameters. A power analysis of the four-wheel skid-steer mobile robot Quadriga has been performed with different loads on concrete and marble floorings.