Abstract: A method is disclosed to smooth the ride of a seat occupant by controlling the damping force of a fluid damper positioned between the seat and base. The method selects between different subprocesses to minimize the ride discomfort and to minimize peak seat accelerations and endstop jerks. The controller uses the input from the different subprocesses to create the best ride for the immediate operational conditions.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: A method/system for controlling helicopter vibrations is provided that includes a vibration canceling force generator for actively generating a vibration canceling force. The system includes a resonant actuator having a natural resonant frequency and a resonant actuator electronic control system. The resonant actuator electronic control system provides an electrical drive current to the resonant actuator to drive the resonant actuator about the resonant frequency when commanded by a received command signal. The resonant actuator has a feedback output with the feedback output fed back into the resonant actuator electronic control system wherein the resonant actuator electronic control system adjusts the electrical drive current based on the resonant actuator feedback output to generate the vibration canceling force.

Abstract: Over-voltage protection circuits are provided for power supplies that may limit input voltage spikes to a power converter and amplifiers including a damping loop that may damp filter resonance. Active damping systems incorporating the over-voltage protection circuits and/or damping loops of the present invention are also provided which may be particularly advantageous in applications such as aircraft or other vehicle applications where size and power consumption are important design considerations. The over-voltage protection circuit in various embodiments senses AC and/or DC voltage levels above a detection threshold level and momentarily disconnects the voltage input to thereby reduce the maximum voltage level input transients seen by the power converter. A capacitor may be provided to maintain the input voltage to the power converter while the input is switched out.