Abstract: An apparatus comprising a variable force suspension system including a wheel, a body portion and a variable force actuator, a sensor for detecting a relative velocity between the wheel and the body portion, a control circuit for detecting an occurrence of a present sign change in the relative velocity, for determining a time lapse between the present sign change and a previous sign change in the relative velocity, and for determining control gains responsive to the determined time lapse, and an actuator controller for controlling the variable force actuator responsive to the determined control gains.

Abstract: A method of control for a vehicle suspension system comprising four quarter car suspensions and a suspended vehicle body, comprising the steps of developing a quarter car command for each quarter car suspension in response to a signal representative of that quarter car state, developing a semi-rigid body command in response to a signal representative of a state of the suspended vehicle body, and developing a force command controlling force between sprung and unsprung masses in each quarter car suspension, the force command equal to the greater of the quarter car command and the semi-rigid body command.