VIBRATION DAMPING DEVICE AND VEHICLE PROVIDED WITH THE VIBRATION DAMPING DEVICE

• US 20120226414A1
• Filed: 05/17/2012
• Published: 09/06/2012
• Est. Priority Date: 11/25/2009
• Status: Active Grant

• Current Assignee: Sinfonia Technology Company Limited
• Original Assignee: Sinfonia Technology Company Limited
• Inventors: MORIYA, Hideaki, MURAGISHI, Yasushi, TOMIZAKI, Takeshi, ITO, Takeo
• Granted Patent: US 9,075,418 B2
• Time in Patent Office: Days
• US Class Current: 701/36
• CPC Class Codes: F16F 15/002 characterised by the control method or circuitry control of mechanical oscillations per se G05D19/00
• CPC Class Codes: F16F 15/005 using electro- or magnetostrictive actuation means generating of mechanical vibrations operating with electrostriction B06B1/06, with magnetostriction B06B1/08; vehicle suspension arrangements characterised by use of piezoelectric elements B60G17/01941; piezoelectric, electrostrictive and magnetostrictive devices per se H10N30/00
• CPC Class Codes: G05D 19/02 characterised by the use of electric means
• CPC Class Codes: G10K 11/17823 Reference signals, e.g. ambient acoustic environment
• CPC Class Codes: G10K 11/17833 by using a self-diagnostic function or a malfunction prevention function, e.g. detecting abnormal output levels
• CPC Class Codes: G10K 11/17854 the filter being an adaptive filter
• CPC Class Codes: G10K 11/17855 for improving speed or power requirements
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17879 using both a reference signal and an error signal

Abstract

A damping device includes a calculator calculating a pseudo vibration to cancel a source vibration transmitted from a vibration source to a position to be damped, using an adaptive control algorithm. The canceling vibration is generated according to the pseudo vibration. A vibration detector detects an error vibration remaining at the position. The adaptive control algorithm is adapted by learning to reduce the error vibration. A frequency recognizer recognizes a frequency of the source vibration from a signal related to the vibration source. The frequency of the vibration is used to determine a frequency of the pseudo vibration. A phase difference identifier identifies a phase difference between the error vibration and the canceling vibration according to the pseudo vibration, and a frequency corrector corrects, according to the phase difference, the frequency of the vibration to eliminate the phase difference.

Claims

1. A vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device comprising:

a calculator including an adaptive control algorithm that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a vibration applying actuator that generates the canceling vibration at the position based on the pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, wherein the adaptive control algorithm is adapted by learning to reduce the remaining vibration;

a frequency recognizer that recognizes a frequency of the vibration at the position based on a signal related to the vibration caused by the vibration generating source, the frequency of the vibration at the position serving as a basis to determine a frequency of the pseudo vibration;

a phase difference identifier that detects the remaining vibration, identifies a phase of the remaining vibration, and identifies a phase difference between the phase of the remaining vibration and a phase of the canceling vibration generated at the position based on the pseudo vibration; and

a frequency corrector that corrects, based on the phase difference, the frequency of the vibration recognized by the frequency recognizer in a direction of eliminating the phase difference.

2. The vibration damping device according to claim 1, wherein

when the phase difference identifier identifies a phase difference, the frequency corrector corrects the frequency of the vibration recognized by the frequency recognizer by a correction amount not exceeding an upper limit correction amount.

3. The vibration damping device according to claim 1, wherein

the frequency corrector corrects the frequency of the vibration recognized by the frequency recognizer with an amount of correction corresponding to an amount of shift of the phase difference identified by the phase difference identifier.

4. The vibration damping device according to claim 1, wherein

the frequency corrector corrects the frequency of the vibration recognized by the frequency recognizer when an amount of shift of the phase difference identified by the phase difference identifier is larger than a threshold value, and does not correct the frequency of the vibration when the amount of shift of the phase difference is equal to or smaller than the threshold value.

5. The vibration damping device according to claim 3, wherein

the frequency corrector corrects the frequency of the vibration recognized by the frequency recognizer when an amount of shift of the phase difference identified by the phase difference identifier is larger than a threshold value, and does not correct the frequency of the vibration when the amount of shift of the phase difference is equal to or smaller than the threshold value.

6. A vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device comprising:

a controller that receives frequency information corresponding to the vibration and generates a canceling signal for canceling the vibration transmitted from the vibration generating source to the position;

a vibration applying actuator that generates, based on the canceling signal, the canceling vibration to be transmitted to the position;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, the controller generating the canceling signal based on the remaining vibration detected by the vibration detector to reduce the remaining vibration at the position;

a memory that stores transmission characteristics corresponding to a vibration transmission path from the vibration applying actuator to the position, the transmission characteristics indicating sensitivity information in association with frequency of the canceling vibration; and

a sensitivity determiner that determines, based on the sensitivity information, whether a present frequency of the canceling vibration is in a low sensitivity region in which the canceling vibration is not substantially transmitted on the vibration transmission path, wherein

when the sensitivity determiner determines that the present frequency of the canceling vibration is in the low sensitivity region, the controller corrects the canceling signal in a direction of suppressing the canceling vibration generated by the vibration applying actuator.

7. The vibration damping device according to claim 6, wherein

the sensitivity determiner determines that the present frequency of the canceling vibration is in the low sensitivity region when a degree of transfer of an amplitude component for the present frequency of canceling vibration is lower than a predetermined first threshold value, wherein the degree of transfer of the amplitude component is one of the transmission characteristics.

8. The vibration damping device according to claim 7, wherein

the sensitivity determiner determines that the present frequency of the canceling vibration is not in the low sensitivity region when the degree of transfer of the amplitude component is higher than a second threshold value, which is higher than the first threshold value,

the sensitivity determiner does not change the determination when the degree of transfer of the amplitude component is between the first threshold value and the second threshold value, and

the controller does not correct the canceling signal when the sensitivity determiner determines that the present frequency of the canceling vibration is not in the low sensitivity region.

9. The vibration damping device according to claim 6, wherein

the canceling signal is a vibration damping current command to be supplied to the vibration applying actuator,

the vibration damping device further comprising:

a current excess detector that provides a predetermined upper limit current value from the frequency information and sends a current upper limit exceeding signal to the controller when a peak current value of the vibration damping current command exceeds the upper limit current value, wherein

the controller, in response to the current upper limit exceeding signal, limits the vibration damping current command, and

the current excess detector corrects the upper limit current value in a direction of limiting the vibration damping current command when the sensitivity determiner determines that the present frequency of the canceling vibration is in the low sensitivity region.

10. A vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device comprising:

a pseudo vibration calculator including an adaptive filter that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a canceling vibration generator that generates the canceling vibration at the position based on the pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, wherein

the pseudo vibration calculator repeats calculation of the adaptive filter to reduce the remaining vibration based on the remaining vibration detected by the vibration detector and a convergence coefficient for determining a speed of convergence of the adaptive filter to a true value, and

the pseudo vibration calculator converges the pseudo vibration and the adaptive filter to the true value by repeating calculations of the adaptive filter;

a deviation information obtainer that obtains deviation information corresponding to a deviation between the vibration transmitted from the vibration generating source to the position and the canceling vibration generated at the position based on the pseudo vibration; and

a convergence coefficient changer that changes, based on the deviation information, the convergence coefficient to increase the speed of convergence of the adaptive filter as the deviation is increased.

13. The vibration damping device according to claim 10, wherein

the deviation information obtainer obtains an applied vibration force amplitude component, as the deviation information, that corresponds to an amplitude value of the canceling vibration generated at the position, and

the convergence coefficient changer changes the convergence coefficient according to the applied vibration force amplitude component obtained by the deviation information obtainer.

11. A vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device comprising:

a pseudo vibration calculator including an adaptive filter that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a canceling vibration generator that generates the canceling vibration at the position based on the pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, wherein

the pseudo vibration calculator repeats calculation of the adaptive filter to reduce the remaining vibration based on the remaining vibration detected by the vibration detector and a convergence coefficient for determining a speed of convergence of the adaptive filter to a true value, and

the pseudo vibration calculator converges the pseudo vibration and the adaptive filter to the true value by repeating calculations of the adaptive filter;

a deviation information obtainer that obtains deviation information corresponding to a deviation between the vibration transmitted from the vibration generating source to the position and the canceling vibration generated at the position based on the pseudo vibration; and

a convergence coefficient changer that changes, based on the deviation information, the convergence coefficient to decrease the speed of convergence of the adaptive filter as the deviation is decreased.

12. A vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling, the vibration damping device comprising:

a pseudo vibration calculator including an adaptive filter that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a canceling vibration generator that generates the canceling vibration at the position based on the pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, wherein

the pseudo vibration calculator repeats calculation of the adaptive filter to reduce the remaining vibration based on the remaining vibration detected by the vibration detector and a convergence coefficient for determining a speed of convergence of the adaptive filter to a true value, and

the pseudo vibration calculator converges the pseudo vibration and the adaptive filter to the true value by repeating calculations of the adaptive filter;

a deviation information obtainer that obtains deviation information corresponding to a deviation between the vibration transmitted from the vibration generating source to the position and the canceling vibration generated at the position based on the pseudo vibration; and

a convergence coefficient changer that changes, based on the deviation information, the convergence coefficient to increase the speed of convergence of the adaptive filter as the deviation is increased and to decrease the speed of convergence of the adaptive filter as the deviation is decreased.

14. A vehicle comprising:

a vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device including;

a calculator including an adaptive control algorithm that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a vibration applying actuator that generates the canceling vibration at the position based on the calculated pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, the adaptive control algorithm adapted by learning to reduce the remaining vibration;

a frequency recognizer that recognizes a frequency of the vibration at the position based on a signal corresponding to the vibration caused by the vibration generating source, the frequency of the vibration at the position serving as a basis to determine a frequency of the pseudo vibration;

a phase difference identifier that detects the remaining vibration, identifies a phase of the remaining vibration, and identifies a phase difference between the phase of the remaining vibration and a phase of the canceling vibration generated at the position based on the pseudo vibration; and

a frequency corrector that corrects, in accordance with the phase difference, the frequency of the vibration recognized by the frequency recognizer in a direction of eliminating the phase difference.

15. A vehicle comprising:

a vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device including;

a controller that receives frequency information corresponding to the vibration and generates a canceling signal for canceling the vibration transmitted from the vibration generating source to the position;

a vibration applying actuator that generates, based on the canceling signal, the canceling vibration to be transmitted to the position;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, the controller generating the canceling signal based on the remaining vibration detected by the vibration detector to reduce the remaining vibration at the position;

a memory that stores transmission characteristics corresponding to a vibration transmission path from the vibration applying actuator to the position, the transmission characteristics indicating sensitivity information in association with frequency of the canceling vibration; and

a sensitivity determiner that determines, based on the sensitivity information, whether a present frequency of the canceling vibration is in a low sensitivity region in which the canceling vibration is not substantially transmitted on the vibration transmission path, wherein

when the sensitivity determiner determines that the present frequency of the canceling vibration is in the low sensitivity region, the controller corrects the canceling signal in a direction of suppressing the canceling vibration generated by the vibration applying actuator.

16. A vehicle comprising:

a vibration damping device for canceling out, at a position to be damped, a vibration caused by a vibration generating source with a canceling vibration, the vibration damping device including;

a pseudo vibration calculator including an adaptive filter that calculates a pseudo vibration to cancel the vibration transmitted from the vibration generating source to the position;

a canceling vibration generator that generates the canceling vibration at the position based on the pseudo vibration;

a vibration detector that detects a remaining vibration remaining as a cancellation error at the position, wherein

the pseudo vibration calculator repeats calculation of the adaptive filter to reduce the remaining vibration based on the remaining vibration detected by the vibration detector and a convergence coefficient for determining a speed of convergence of the adaptive filter to a true value, and

the pseudo vibration calculator converges the pseudo vibration and the adaptive filter to the true value by repeating calculations of the adaptive filter;

a deviation information obtainer that obtains deviation information corresponding to a deviation between the vibration transmitted from the vibration generating source to the position and the canceling vibration generated at the position based on the pseudo vibration; and

a convergence coefficient changer that changes, based on the deviation information, the convergence coefficient to increase the speed of convergence of the adaptive filter as the deviation is increased.