No-jerk semi-active skyhook control method and apparatus

A method of controlling a controllable force generator within a controllable suspension system interconnected between a first member M.sub.1 and a second member M.sub.2. The method includes the steps of obtaining a first signal (V.sub.abs) representative of the absolute velocity of the first member M.sub.1, obtaining a second signal (V.sub.rel) representative of the relative velocity between the first and second members, and setting a desired damping force for the generator based upon a control policy which defines a control surface. The control policy includes a preselected gain, an absolute velocity, and a shaping function of relative velocity wherein said control surface exhibits only continuous first derivatives for V.sub.rel *V.sub.abs >0 and wherein the control surface is devoid of any surface discontinuities. This control policy effectively eliminates the jerkiness in certain prior art control methods, such as skyhook.