  Composite adaptive control schemes, which use both the system tracking errors
and the prediction error to drive the update laws, have become widespread in
achieving an improvement of system performance. However, a strong
persistent-excitation (PE) condition should be satisfied to guarantee the
parameter convergence. This paper proposes a novel composite adaptive control
to guarantee parameter convergence without PE condition for nonlinear
teleoperation systems with dynamic uncertainties and time-varying communication
delays. The stability criteria of the closed-loop teleoperation system are
given in terms of linear matrix inequalities. New tracking performance measures
are proposed to evaluate the position tracking between the master and the
slave. Simulation studies are given to show the effectiveness of the proposed
method.
