Robust variable structure and adaptive control of multi-arm dynamics

The authors have analyzed and simulated the combination of the continuous VSC and the switching-sigma modification control laws for multi-arm manipulators with rigid links holding a rigid object. Although the simulations show that the Cartesian position error is small if the boundary layer is small and/or the estimated resultant force/torque is close to the desired resultant force/torque even if the actuator unmodeled dynamics are considered, the small boundary layer is limited by the physical limitation. The closeness between the estimated resultant force/torque and the desired resultant force/torque is also limited by the measurement or estimation