Abstract: This paper proposes a nonlinear digital PD corrector scheme where a nonlinoar link of "Anti--Backlash" has been introduced into the nonrocursive digital filter of PD nature, the latter will adjust and update itself in real time with a certain quantity characterizing the dynamic performance. The resultant corrector gives much improvement in dynamics(stability and accuracy) as compared with the linear filter (corrector). An example of time variant attitude control system has been given to show the merit of this new scheme.