Stability and performance of image based visual servo control using first order spherical image moments.

Image moments provide an important class of image features used for image-based visual servo control. Spherical image moments have the additional desirable property that they are invariant under rotation of the camera frame. For these features one can study the local and global stability and performance of the position control independently of the rotation control. In this paper we study a range of control algorithms including the classical approximately linearising control, a recently proposed robust control based on Lyapunov function design methodology, and modi cations of these designs to improve global and asymptotic performance and robustness of the schemes. The comparison of performance demonstrates that the choice of image feature and control design for image-based visual servo are each equally important and highly coupled. We nally propose a control law using a modi ed image feature and a Lyapunov control design that ensures global asymptotic stability and good performance equally in image space as in task space.