Comments on 'An adaptive control scheme for robot manipulators'

Based on an extension of the classical linearization method, an adaptive control scheme has recently been proposed by Choi et al. (1986). This control scheme, however, implicitly involves taking the inverse of the matrix [I + G(x(t), u(x(t)))], which complicates the computation. Moreover, since the matrix inversion depending on the system state x(t) does not necessarily exist for all time, the proposed control scheme may lose its effectiveness. In this paper, we present a modified control scheme in which the aforementioned weakness does not appear.