A reduced-order adaptive velocity observer for manipulator control

In this paper a new manipulator joint velocity observer is presented. The observer is reduced in its order and it is adaptive with respect to unknown dynamic parameters. The velocity estimate produced by the observer is used in an adaptive controller for trajectory tracking. The result is locally asymptotically stable velocity observation errors and locally asymptotically stable position and velocity trajectory tracking errors. Simulations of the proposed scheme on the PUMA-560 show an improvement over a well known adaptive controller which obtains its joint velocity estimates via numerical differentiation experiments demonstrate the usefulness of the proposed observer.>