Vibration/noise control system including adaptive digital filters for simulating dynamic characteristics of a vibration/noise source having a rotating member

• US 5,912,821 A
• Filed: 03/17/1997
• Issued: 06/15/1999
• Est. Priority Date: 03/21/1996
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Kobayashi, Toshiaki
• Primary Examiner(s): WACHSMAN, HAL D
• Application Number:
  US08/819,215
• Time in Patent Office: 820 Days
• Field of Search: 364/528.15, 364/528.1, 364/148.01, 364/148.09, 364/148.1, 364/194, 364/724.012, 364/724.19, 364/824, 364/825, 364/578, 364/802, 364/816, 381/71.11, 381/71.12, 381/71.8, 381/71.4, 381/71.7, 381/73.1, 381/86, 381/94.1, 381/94.2, 381/94.8, 381/94.9, 701/111, 702/17, 702/33-35, 702/39, 702/42, 702/56, 702/79, 702/103, 702/105, 702/111, 702/113, 702/125, 702/189-191, 702/195, 702/197, 702/199, 73/35.09, 73/570, 73/571, 73/577, 73/579, 73/659, 73/660, 73/662, 73/496, 73/504.04, 73/504.12, 73/514.15, 73/DIG. 1, 706/14, 706/22, 706/903, 706/904, 706/905, 706/907, 706/912, 706/913, 706/915
• US Class Current: 700/280
• CPC Class Codes: F16F 15/02 Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems F16F15/005 takes precedence ; layered products B32B; suppression of vibration in ships B63; relieving load on bearings, using magnetic means F16C39/06
• CPC Class Codes: G10K 11/17817 between the output signals and the error signals, i.e. secondary path
• 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 11/17883 the reference signal being derived from a machine operating condition, e.g. engine RPM or vehicle speed
• CPC Class Codes: G10K 2210/121 Rotating machines, e.g. engines, turbines, motors; Periodic or quasi-periodic signals in general
• CPC Class Codes: G10K 2210/1282 Automobiles
• CPC Class Codes: G10K 2210/1291 Anti-Vibration-Control, e.g. reducing vibrations in panels or beams
• CPC Class Codes: G10K 2210/30232 Transfer functions, e.g. impulse response
• CPC Class Codes: G10K 2210/3211 Active mounts for vibrating structures with means to actively suppress the vibration, e.g. for vehicles
• CPC Class Codes: G10K 2210/502 Ageing, e.g. of the control system
• CPC Class Codes: G10K 2210/511 Narrow band, e.g. implementations for single frequency cancellation

Abstract

A control system for controlling vibrations and noises generated by a vibration/noise source having at least a rotating member includes a first filter which generates a control signal for controlling the vibrations and noises. A self-expanding engine mount is arranged in a noise transmission path and converts the control signal into a driving signal for driving the noise source. An error sensor detects an error signal indicative of a difference between the driving signal and the vibrations and noises. A second filter stores a transfer characteristic of a portion of the noise transmission path extending between the first filter and the error sensor, and generates a reference signal based on the transfer characteristic. The control signal is updated in a manner such that the error signal is minimized. In addition, adaptive digital filters are provided for simulating both a dynamic characteristic of a physical system extending between the first filter and a predetermined control area and a dynamic characteristic of the portion of the transmission path extending between the first filter and the error sensor. The filter coefficients of the adaptive digital filters are updated in accordance with a genetic algorithm.

Claims

1. A vibration/noise control system for controlling vibrations and noises generated with a periodicity or a quasi-periodicity from a vibration/noise source having at least a rotating member, said system comprising:

timing pulse signal-detecting means for detecting at least one timing pulse signal indicative of a period of vibrations and noises peculiar to at least one component part of said vibration/noise source;

first filter means for generating a control signal for controlling said vibrations and noises from said vibration/noise source, said first filter means comprising an adaptive digital filter and having an adjustable filter coefficient;

electromechanical transducer means, arranged in at least one vibration/noise transmission path through which said vibrations and noises from said vibration/noise source are transmitted, for converting said control signal into a driving signal for driving said vibration/noise source;

error signal-detecting means for detecting an error signal indicative of a difference between said driving signal and a vibration/noise signal indicative of said vibrations and noises from said vibration/noise source;

second filter means for storing a transfer characteristic of a portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means, and for generating a reference signal based on said transfer characteristic and said at least one timing pulse signal, said second filter means also having an adjustable filter coefficient;

control signal-updating means for updating said filter coefficient of said first filter means so that said first filter means generates said control signal in a manner such that said error signal is minimized, based on said error signal, said reference signal and said filter coefficient of said first filter means;

first dynamic characteristic-identifying means for simulating a dynamic characteristic of a physical system extending between said first filter means and a predetermined control area;

second dynamic characteristic-identifying means for simulating a dynamic characteristic of said portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means; and

reference signal-updating means for updating said filter coefficient of said second filter means based on a simulation result of said second dynamic characteristic-identifying means;

wherein each of said first and second dynamic characteristic-identifying means includes an adaptive digital filter having a filter coefficient, and filter coefficient-updating means for updating said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means.

2. A vibration/noise control system as claimed in claim 1, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means in accordance with one of a genetic algorithm, an LMS algorithm and a neuro algorithm.

3. A vibration/noise control system as claimed in claim 2, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means:

(i) calculates values of a performance function based on a residual signal representing a difference between said error signal and a quasi error signal from said first and second dynamic characteristic-identifying means in accordance with said genetic algorithm, and (ii) updates said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means according to an optimum one of the calculated values of said performance function.

4. A vibration/noise control system as claimed in claim 3, wherein said filter coefficient-updating means of said first dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of said first dynamic characteristic-identifying means based on said optimum one of the calculated values of said performance function and said at least one timing pulse signal from said timing pulse signal-detecting means, and wherein said filter coefficient-updating means of said second dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of said second dynamic characteristic-identifying means based on said optimum one of the calculated values of said performance function and said control signal from said first filter means.

5. A vibration/noise control system as claimed in claim 3, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means calculates said performance function in a manner such that a value of said residual signal is minimized.

6. A vibration/noise control system as claimed in claim 1, further comprising:

rotational speed-detecting means for detecting a rotational speed of said rotating member based on a detection result of said timing pulse signal-detecting means;

first dynamic characteristic-storing means for storing said simulated dynamic characteristic of said physical system extending between said first filter means and said predetermined control area as a function of the rotational speed of said rotating member;

second dynamic characteristic-storing means for storing said simulated dynamic characteristic of said portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means as a function of the rotational speed of said rotating member; and

dynamic characteristic-updating means for updating said simulated dynamic characteristics stored in said first and second dynamic characteristic-storing means based on updated simulation results of said first and second dynamic characteristic-identifying means.

7. A vibration/noise control system for controlling vibrations and noises generated with a periodicity or a quasi-periodicity from a vibration/noise source having at least a rotating member, said system comprising:

timing pulse signal-detecting means for detecting at least one timing pulse signal indicative of a period of vibrations and noises peculiar to at least one component part of said vibration/noise source;

sine wave-generating means for generating a reference sine wave having a single repetition period dependent upon time intervals of generation of said at least one timing pulse signal;

delayed sine wave-generating means for generating a delayed sine wave which is delayed by a delay period T of 1/3≧

T≧

1/7 relative to said reference sine wave, wherein T is a real number;

first filter means for generating a control signal for controlling said vibrations and noises from said vibration/noise source, said first filter means comprising an adaptive digital filter including two taps, and said first filter means having an adjustable filter coefficient;

electromechanical transducer means, arranged in at least one vibration/noise transmission path through which said vibrations and noises from said vibration/noise source are transmitted, for converting said control signal into a driving signal for driving said vibration/noise source;

error signal-detecting means for detecting an error signal indicative of a difference between said driving signal and a vibration/noise signal indicative of said vibrations and noises from said vibration/noise source;

second filter means for storing a transfer characteristic of a portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means, and for generating a reference signal based on said transfer characteristic and said at least one timing pulse signal, said second filter means also having an adjustable filter coefficient;

control signal-updating means for updating said filter coefficient of said first filter means so that said first filter means generates said control signal in a manner such that said error signal is minimized, based on said error signal, said reference signal and said filter coefficient of said first filter means;

first dynamic characteristic-identifying means for simulating a dynamic characteristic of a physical system extending between said first filter means and a predetermined control area;

second dynamic characteristic-identifying means for simulating a dynamic characteristic of said portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means; and

reference signal-updating means for updating said filter coefficient of said second filter means based on a simulation result of said second dynamic characteristic-identifying means;

wherein each of said first and second dynamic characteristic-identifying means includes an adaptive digital filter having a filter coefficient, and filter coefficient-updating means for updating said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means; and

wherein said adaptive digital filter of each of said first and second dynamic characteristic means includes two taps.

8. A vibration/noise control system as claimed in claim 7, wherein said delay period T is set to 1/4 of a repetition period of said reference sine wave.

9. A vibration/noise control system as claimed in claim 7, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means in accordance with one of a genetic algorithm, an LMS algorithm and a neuro algorithm.

10. A vibration/noise control system as claimed in claim 9, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means:

(i) calculates values of a performance function based on a residual signal representing a difference between said error signal and a quasi error signal from said first and second dynamic characteristic-identifying means in accordance with said genetic algorithm, and (ii) updates said filter coefficient of said adaptive digital filter of each of said first and second dynamic characteristic-identifying means according to an optimum one of the calculated values of said performance function.

11. A vibration/noise control system as claimed in claim 10, wherein said first filter means generates a first control signal corresponding to said reference sine wave and a second control signal corresponding to said delayed sine wave, wherein said filter coefficient-updating means of said first dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of said first dynamic characteristic-identifying means based on said optimum one of the calculated values of said performance function and one of said reference sine wave and said delayed sine wave, and wherein said filter coefficient-updating means of said second dynamic characteristic-identifying means updates said filter coefficient of said adaptive digital filter of said second dynamic characteristic-identifying means based on said optimum one of the calculated values of said performance function and said first and second control signals.

12. A vibration/noise control system as claimed in claim 10, wherein said filter coefficient-updating means of each of said first and second dynamic characteristic-identifying means calculates said performance function in a manner such that a value of said residual signal is minimized.

13. A vibration/noise control system as claimed in claim 7, further comprising:

rotational speed-detecting means for detecting a rotational speed of said rotating member based on a detection result of said timing pulse signal-detecting means;

first dynamic characteristic-storing means for storing said simulated dynamic characteristic of said physical system extending between said first filter means and said predetermined control area as a function of the rotational speed of said rotating members;

second dynamic characteristic-storing means for storing said simulated dynamic characteristic of said portion of said at least one vibration/noise transmission path extending between said first filter means and said error signal-detecting means as a function of the rotational speed of said rotating member; and

dynamic characteristic-updating means for updating said simulated dynamic characteristics stored in said first and second dynamic characteristic-storing means based on updated simulation results of said first and second dynamic characteristic-identifying means.