Reconfiguration of four legged walking robot for actuator faults

Abstract

This paper presents fault tolerant control through reconfiguration of a four legged walking robot. It is assumed that the walking robot motion is in sagittal plane and it follows the bounding gait. The bond graph model of walking robot in sagittal plane is developed. A novel and simple attitude control device based on the motion of the moving appendage is proposed. The bond graph model of the system is used to generate the Analytical Redundancy Relations (ARRs) which are then evaluated with actual measurements to generate residuals. These residuals are used to perform structural fault isolation. Once the fault list is updated in the equipment availability database, an automaton selects the best option to reconfigure the system such that the given control objectives are achieved. The developed methodology is validated by considering the joint actuator failure.