Аннотация:A problem of protection of an object on a movable base from transient impacts by means of an active shock isolator is considered. The peak magnitude of the displacement of the object relative to the base is chosen as the performance index to be minimized. Based on the optimal control without anticipation for the instantaneous impact, a guaranteeing control with optimized instant of engagement is constructed. The control that involves optimization of the engagement instant is compared with other control strategies.