Demonstrating an active vibration isolation system
View Patent ↗Active vibration isolation (AVI) systems are becoming more available in various markets, one such market being vehicle operator seating. Unfamiliarity with the performance of such systems may cause users initial perceptions of system performance to be unfavorable. AVI systems can include a demonstration system capable of providing simulations too users of various types of vibration isolation systems under various input conditions, so that users can be introduced to the system benefits over other systems before using an AVI equipped product in its intended application.
1. A method for providing audible sound and output motion in an active vibration isolation system that comprises a current feedback loop wherein a measured multiphase actuator drive current is compared to a command current for the multiphase actuator, to form an error signal that is used to drive the multiphase actuator, the method comprising:
providing by the active vibration isolation system an audio signal, wherein the audio signal is pre-filtered to invert audio signal rejection that the current feedback loop exerts on the audio signal;
commutating the pre-filtered audio signal to provide commutated audio output signals;
providing by the active vibration isolation system a motion command signal;
commutating the motion command signal to provide commutated motion output signals, and
combining the commutated audio output signals and the commutated motion output signals to form commutated combined output signals for provision to individual phases of the multiphase actuator, to simultaneously provide output motion and an audible acoustic signal.
2. The method of claim 1 wherein the audio signal is further pre-filtered to provide equalization to correct for deviations in the system linear acoustic transfer function from a desired reference acoustic response.
3. The method of claim 1 wherein the total harmonic distortion of the audible acoustic signal is less than 10%.
4. The method of claim 1 wherein the active vibration isolation system is configured and arranged to isolate a suspended seat from a vehicular vibration disturbance.
5. The method of claim 1 wherein the active vibration isolation system further comprises a demonstration system configured to control the audible acoustic signals.
6. The method of claim 5 wherein the audible acoustic signals communicate information about the demonstration.
7. The method of claim 1 wherein the audible acoustic signals communicate a status condition of a system of a vehicle in which the active vibration isolation system is mounted.
8. The method of claim 1 wherein the audible acoustic signals communicate a fault condition of the active vibration isolation system.
9. The method of claim 1 wherein the audible acoustic signals communicate tutorial information on how to operate the active vibration isolation system.
10. An active vibration isolation system for providing vibration isolation and audible sound, the system comprising:
a multi-phase actuator for outputting force to a suspended payload;
a controller for outputting force commands;
a commutator for converting force commands into currents provided to phases of the multi-phase actuator,
wherein the currents provided to the actuator are comprised of a first component which causes a force to be output by the multi-phase actuator to provide vibration isolation of the payload, and a second component which causes a force to be output by the multi-phase actuator for causing audible sound to be radiated by the payload;
a current feedback loop wherein a measured multi-phase actuator drive current is compared to a command current for the multi-phase actuator, to form an error signal that is used to drive the multi-phase actuator; and
a pre-filter that is adapted to invert rejection that the current feedback loop exerts on the second component of the currents provided to the actuator.
11. The active vibration isolation system of claim 10 further comprising a demonstration system configured to control the component of force for producing audible sound.
12. The active vibration isolation system of claim 11 wherein the audible sound communicates information about the demonstration.
13. The active vibration isolation system of claim 10 wherein the audible sound communicates information about a status condition of a system of a vehicle in which the active vibration isolation system is mounted.
14. The active vibration isolation system of claim 10 wherein the audible sound communicates information about a fault condition of the active vibration isolation system.
15. The active vibration isolation system of claim 10 wherein the audible sound communicates tutorial information on how to operate the vibration isolation system.
16. The active vibration isolation system of claim 10 wherein the actuator has sufficient bandwidth to cause the payload to output audible speech.
17. The active vibration isolation system of claim 16 wherein the multi-phase actuator has a bandwidth up to at least 5 KHz.
18. The active vibration isolation system of claim 16 wherein the multi-phase actuator comprises at least one of a rotary or linear electromagnetic actuator.
19. A method for providing audible sound and output motion in an active vibration isolation system that comprises a current feedback loop wherein a measured multi-phase actuator drive current is compared to a command current for the multi-phase actuator, to form an error signal that is used to drive the multi-phase actuator, the method comprising:
providing an audio signal to an active vibration isolation system having a controller with an input adapted for accepting the audio signal, wherein the audio signal is pre-filtered to invert audio signal rejection that the current feedback loop exerts on the audio signal;
providing vibration signals output from vibration sensors to the active vibration isolation system controller, the controller having inputs adapted for accepting the vibration signals output by the vibration sensors;
generating from the pre-filtered audio signal an audio force command for application to a commutation system, wherein the commutation system outputs audio currents adapted for application to phases of the multi-phase actuator of the active vibration isolation system, for causing an audio output to be radiated by a payload of the active vibration isolation system when the audio force command is applied;
generating a vibration force command for application to the commutation system, wherein the commutation system outputs vibration currents adapted for application to phases of the multi-phase actuator of the active vibration isolation system, for causing vibration of the payload of the active vibration isolation system to be controlled when the vibration force command is applied;
combining the audio phase currents with the vibration phase currents; and
applying the combined phase currents to phases of the multi-phase actuator.