Investigation of the dynamic behavior of a slider crank mechanism-based wheel-legged mobile robot

Abstract This paper presents the design and dynamic analysis of a reconfigurable four-wheeled mobile robot, with front wheels capable of transforming from a conventional circular wheel into a five-spoke wheel-legged (wheg) configuration. The transformation is achieved through a reconfiguration mechanism integrating a slider-crank chain with a rack and pinion system. A comprehensive dynamic analysis of the mechanism is conducted to evaluate the torque requirements for actuation and to support the selection of a suitable off-the-shelf motor. The required actuation torque is primarily influenced by the normal contact (reaction) force between the wheel and the ground or terrain, which varies depending on surface or terrain conditions. This contact force is computed using system dynamics, and its variations are further analyzed through the robot’s dynamic response. Numerical simulations, supported by real-world field tests, validate the effectiveness of the proposed design in moderately uneven environments.