EP0103256A1 - Verfahren und Schaltung zur Unterdrückung akustischer und mechanischer Schwingungen - Google Patents

Verfahren und Schaltung zur Unterdrückung akustischer und mechanischer Schwingungen Download PDF

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Publication number
EP0103256A1
EP0103256A1 EP83108765A EP83108765A EP0103256A1 EP 0103256 A1 EP0103256 A1 EP 0103256A1 EP 83108765 A EP83108765 A EP 83108765A EP 83108765 A EP83108765 A EP 83108765A EP 0103256 A1 EP0103256 A1 EP 0103256A1
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EP
European Patent Office
Prior art keywords
sensor
vibrations
output
signal
acoustic
Prior art date
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Granted
Application number
EP83108765A
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English (en)
French (fr)
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EP0103256B1 (de
Inventor
Michel Garçonnat
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sintra Alcatel SA
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Sintra Alcatel SA
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Publication date
Application filed by Sintra Alcatel SA filed Critical Sintra Alcatel SA
Publication of EP0103256A1 publication Critical patent/EP0103256A1/de
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    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17857—Geometric disposition, e.g. placement of microphones
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1781—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions
    • G10K11/17821—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions characterised by the analysis of the input signals only
    • G10K11/17823—Reference signals, e.g. ambient acoustic environment
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17853—Methods, e.g. algorithms; Devices of the filter
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17873—General system configurations using a reference signal without an error signal, e.g. pure feedforward
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/129—Vibration, e.g. instead of, or in addition to, acoustic noise
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3018—Correlators, e.g. convolvers or coherence calculators
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3025—Determination of spectrum characteristics, e.g. FFT
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3028—Filtering, e.g. Kalman filters or special analogue or digital filters
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3042—Parallel processing
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3045—Multiple acoustic inputs, single acoustic output
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3216—Cancellation means disposed in the vicinity of the source

Definitions

  • the subject of the present invention is a method and devices for eliminating the effects of acoustic or mechanical vibrations, in particular with a view to creating a zone of silence with respect to one or more sources of noise or preventing the transmission of mechanical vibrations produced by one or more sources of undesirable mechanical vibrations.
  • damping vibrations is often difficult to achieve insofar as it is possible to stifle a known pure frequency vibration emitted by a well-defined source, it is much more difficult to stifle a set of vibrations whose the characteristics are only known globally.
  • the present invention therefore relates to a method and devices for canceling the effects of acoustic or mechanical vibrations.
  • a signal is obtained, for the benefit of a slave transducer, obtained by summing correction signals themselves obtained by individual correlation of a signal received by at least one first sensor located upstream of the environment to be protected, with a plurality of line energy density signals each obtained by different narrow filtering from a signal received by at least one second sensor located on, against or close to the source or sources from which the vibrations are to be eliminated, the application of the signal obtained to the transducer causing the creation of vibration in phase opposition with those generated by the source or sources.
  • a device for eliminating the annoying effects of acoustic vibrations in an area to be protected associates with at least one first acoustic sensor placed upstream of the area to be protected relative to the area where the or annoying sources of vibration, to at least one second sensor placed on or near the sources and to at least one acoustic transducer, a corrector assembly composed of an adder whose output controls the transducer and whose inputs are connected to a plurality correlation modules themselves connected on the one hand at the output of the first sensor and on the other hand individually at the output of as many line filters, with very narrow band, connected at the output of the second sensor, each line filter providing an energy density signal for a line different from that of the other filters.
  • a device for canceling parasitic mechanical vibrations transmitted by an apparatus to its environment via at least one physical link associates with at least a first link vibration sensor, with at least a second sensor. vibration of the apparatus and at least one servo damper, inserted between the apparatus and the link, a corrector assembly as defined above.
  • the cancellation device is essentially intended to eliminate the effects of unwanted acoustic or mechanical vibrations, from signals obtained from at least two sensors referenced 1 and 2 in FIG. 1 in the case of elimination of acoustic vibrations and 1 ′ and 2 ′ in the case of elimination of mechanical vibrations. It therefore aims to create a zone z protected from the noise created by an AP source in the first hypothesis and to avoid the transmission of mechanical vibrations from an AP 'apparatus to its environment via the EL links which connect it to the latter. , in particular its base or its support points, in the second hypothesis.
  • a sensor 1 is placed upstream of a zone z which one wishes to protect in space Z where the source AP exhibits its annoying acoustic effects and a sensor 2 is placed against on or near from the AP source so as to capture the noise emissions.
  • the sensors 1 and 2 are for example microphones, the sensor 1 is possibly a room microphone and the microphone 2 a directional microphone, or even an accelerometer if the noises are of mechanical origin.
  • a sensor 1 ′ is placed on or against the connection (s) EL by which the mechanical vibrations created by the apparatus AP ′ are capable of being transmitted to its environment, not shown.
  • a sensor 2 ' is placed against or on the apparatus AP', it being understood that at least one servo-controlled damper AM is inserted between each link EL and the apparatus AP 'to avoid transmissions of mechanical vibrations.
  • the sensors 1 ′ and 2 ′ are then for example accelerometers
  • the damper AM is for example a damper 11 controlled by electrical control and it is inserted for example between the frame of the apparatus AP ′ and the base serving as a support which then forms the EL bond.
  • sensors 1 and 2 or 1 'and 2' can vary depending on the existing constraints, however insofar as the principle remains the same, a single sensor 1 and a single sensor 2, or a single sensor 1 'and a single sensor 2 ′ is taken into account in the following description.
  • the signals b '(t) generated by the sensor 2, or 2' depending on the case and the signals b (t) generated by the capt are used.
  • the signal b '(t) of the duly amplified sensor 2 is applied to a plurality of narrow-band filters 3a to 3n, called line filters, which are individually centered on different frequencies distributed in the auditory disturbing spectrum.
  • Each line filter 3 provides a reference b '(f) representing the energy spectral density of the noise received by the sensor 2 for the frequency considered as b' (fa) for the line filter 3a centered on the frequency fa.
  • Each filter 3 is connected to an input of a correlation module 4 which is specific to it and which has a second input connected to the output of the sensor 1 from which it therefore receives the signal b (t).
  • the correlation modules 4 are for example of the type described in French patent 2215005 of the Applicant and presented in FIG. 2.
  • the application of the signal S (t) to the acoustic transducer HP causes the emission by the latter of signals in phase opposition with those coming from the noise source AP in the zone z where this transducer is effective.
  • the application of the signal S (t) to the control circuit, not shown, of the controlled damper AM causes the creation in this damper of mechanical vibrations in phase opposition with the mechanical vibrations coming from the apparatus AP ', which are thus thus canceled at the level of the EL connection, for example at the level of the base carrying the apparatus.
  • line filters 3 are necessarily limited as long as one does not use a signal conversion in digital form and it is therefore the filter adjustment possibilities which make it possible to select the lines intended to make the object of correction, since in the most general case, only the energy of certain lines is to be taken into account, the others being either negligible or nonexistent.
  • An attenuation device applying the method according to the invention can advantageously be implemented after conversion of the signals produced by the sensors from an analog form to a digital form, taking advantage of the advantages brought by the Fourier transformations and more particularly the fast Fourier transformations (FFT).
  • FFT fast Fourier transformations
  • each sensor 1 or 2 is connected to an appropriate analog-digital converter 7 and each converter supplies the results of its conversions to a set 8 ′ constituted by a computer capable of calculating a fast double Fourier transform FFT1 , FFT2 from the signals received from each of the converters to deduce therefrom a signal summing the correlated corrections made by each line at the transform point.
  • a set 8 ′ constituted by a computer capable of calculating a fast double Fourier transform FFT1 , FFT2 from the signals received from each of the converters to deduce therefrom a signal summing the correlated corrections made by each line at the transform point.
  • This sum signal is then the object of a Fourier transformation. fast reverse, the result of which is applied to the loudspeaker HP or to the damper AM via a digital-analog converter (9) and possible amplifiers in order to obtain the previously mentioned effects.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
EP83108765A 1982-09-09 1983-09-06 Verfahren und Schaltung zur Unterdrückung akustischer und mechanischer Schwingungen Expired EP0103256B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8215280A FR2533057B1 (fr) 1982-09-09 1982-09-09 Procede et dispositifs pour l'elimination des effets de vibrations acoustiques ou mecaniques
FR8215280 1982-09-09

Publications (2)

Publication Number Publication Date
EP0103256A1 true EP0103256A1 (de) 1984-03-21
EP0103256B1 EP0103256B1 (de) 1988-02-24

Family

ID=9277320

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83108765A Expired EP0103256B1 (de) 1982-09-09 1983-09-06 Verfahren und Schaltung zur Unterdrückung akustischer und mechanischer Schwingungen

Country Status (5)

Country Link
EP (1) EP0103256B1 (de)
AU (1) AU1874983A (de)
CA (1) CA1208351A (de)
DE (1) DE3375744D1 (de)
FR (1) FR2533057B1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992008224A1 (en) * 1990-10-29 1992-05-14 Noise Cancellation Technologies Inc. Active vibration control system with multiple inputs
WO1994009482A1 (en) * 1992-10-21 1994-04-28 Lotus Cars Limited Adaptive control system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4432532A1 (de) * 1994-09-13 1996-03-14 Stn Atlas Elektronik Gmbh Verfahren zur Befreiung von Körperschallstörungen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB782794A (en) * 1955-02-09 1957-09-11 Gen Electric Improvements relating to noise reduction applicable to electric induction apparatus and other sound sources
US4232381A (en) * 1979-06-08 1980-11-04 Northrop Corporation Noise cancellation using tracking filter
EP0043565A1 (de) * 1980-07-03 1982-01-13 Hitachi, Ltd. Vorrichtung zur Vibrations- und/oder Lärmreduktion für elektrische Geräte

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB782794A (en) * 1955-02-09 1957-09-11 Gen Electric Improvements relating to noise reduction applicable to electric induction apparatus and other sound sources
US4232381A (en) * 1979-06-08 1980-11-04 Northrop Corporation Noise cancellation using tracking filter
EP0043565A1 (de) * 1980-07-03 1982-01-13 Hitachi, Ltd. Vorrichtung zur Vibrations- und/oder Lärmreduktion für elektrische Geräte

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992008224A1 (en) * 1990-10-29 1992-05-14 Noise Cancellation Technologies Inc. Active vibration control system with multiple inputs
AU660291B2 (en) * 1990-10-29 1995-06-22 Noise Cancellation Technologies, Inc. Active vibration control system with multiple inputs
WO1994009482A1 (en) * 1992-10-21 1994-04-28 Lotus Cars Limited Adaptive control system
US5691893A (en) * 1992-10-21 1997-11-25 Lotus Cars Limited Adaptive control system

Also Published As

Publication number Publication date
FR2533057B1 (fr) 1986-05-16
DE3375744D1 (en) 1988-03-31
AU1874983A (en) 1984-03-15
EP0103256B1 (de) 1988-02-24
FR2533057A1 (fr) 1984-03-16
CA1208351A (fr) 1986-07-22

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