Stability and L2-Gain Performance Analysis for Robust Visual Servo System

In this paper, we deal with disturbance attenuation property of a controller for the visual servo systems. First, based on Lyapunov stability theory, we propose an asymptotically stable controller without exogenous inputs, e.g. the joint torque disturbances and the motion of a target. Next we show that the proposed controller achieves disturbance attenuation in the L2-gain sense, that is, the L2-gain of the closed loop system from the exogenous inputs to the regulated outputs can be made sufficiency small with a suitable selection of the feedback gains. Finally, our experiments on an industrial manipulator are shown to evaluate the effectiveness of the proposed controller and L2-gain performance analysis for the visual servo system.