Active seat suspension control system

Abstract

A suspension system supports a seat with respect to a base mounted on a frame of a vehicle. The system includes a hydraulic actuator coupled between the seat and the base. A single accelerometer is attached to the base and generates a base acceleration signal in response to motion of the base. A control unit actively controls the hydraulic actuator as a function of the base acceleration signal. The control unit generates a base velocity signal by integrating the base acceleration signal, generates a seat position signal representing a position of the seat relative to the base, generates a seat position error signal representing a difference between a desired position and the seat position signal, and generates a command signal as a function of the velocity signal and of the position error signal. The control unit controls the actuator by applying the command signal thereto.

1 . An active suspension system for supporting a seat on a base of a vehicle, comprising: 
 an actuator coupled between the seat and the base for moving the seat relative to the base;    only a single accelerometer, said single accelerometer being attached directly to the base and generating only a single base acceleration signal in response to vertical motion of the base; and    a control unit which converts only the single base acceleration signal into a control signal, and actively controls the actuator as a function of the control signal.    
   
   
       2 . The suspension system of  claim 1 , wherein: 
 the control unit generates a base velocity signal by integrating the base acceleration signal;    the control unit generates a seat position signal representing a position of the seat relative to the base;    the control unit generates a seat position error signal representing a difference between a desired position and the seat position signal;    the control unit generates the control signal as a function of the base velocity signal and of the position error signal; and    the control unit controls the actuator by applying the control signal thereto.    
   
   
       3 . (canceled)  
   
   
       4 . The suspension system of  claim 1 , wherein: 
 the control unit and the actuator cooperate so that the velocity of the actuator will be proportional to a magnitude of the control signal.