Abstract: A system and method for controlling an electrically controlled pressure relief valve may use a soft position control loop to control the position of the valve. A pressure relief valve may also include a modified orifice shape to improve stability, to uniformly distribute the effective bandwidth over the valve operating range, and to provide a tunable default mode.

Abstract: A semi-active control methodology is provided for a spring/mass system, for example a real-time adjustable shock absorber system. The methodology includes defining a plurality of operating zones based on system parameters and user-definable or preset inputs. The methodology also includes processing to account for non-inertial spring/mass system response and multidimensional forces acting on the system, and an acceleration hedge calculation to accurately define system operation at extrema of travel. The methodology is generally directed at producing a plurality of valve control signals, selecting among the valve control signals, and applying the selected control signal to the valve in a closed-loop feedback system to adjust the energy in the spring/mass system.