Fault Tolerant Control and Reconfiguration of Mobile Manipulator

Trajectory control of mobile manipulator under joint lock failure poses new challenges. In this work fault tolerant scheme is proposed for trajectory control under joint lock failure through reconfiguration while exploiting the existing redundancy of the mobile manipulator system. Closed loop inverse kinematics (CLIK) algorithm are employed to transform the tip trajectory control problem to joint space control problem. In this work, two kinds of reconfiguration schemes are proposed, one using the redundancy in the manipulator only and another using the redundancy available with complete mobile manipulator system. Both types of the reconfiguration schemes use CLIK algorithm to calculate mobile base position and manipulator joint configurations so that the tip follows the reference trajectory in spite of locked joint failure of manipulator. Simulation and experimental results are presented to validate the proposed fault tolerant schemes.