a magnetic actuator for providing a single - axis , noncontacting force capability with unconstrained cross - axis mobility utilizes flux feedback force linearization . electromagnets cooperating with an armature suspended therebetween are energized by a bias flux and a signal derived from flux densities sensed in the air gaps . the bias flux density may be optimized to minimize the peak power required by the actuator . the flux density signals are applied in a closed force loop to provide a net force directly proportional to the commanded flux .