System and method for actively influencing sound

Patent metadata

Field	Value
Publication number	US-10002603-B2
Application number	US-201715479946-A
Country	US
Kind code	B2
Filing date	Apr 5, 2017
Priority date	Apr 6, 2016
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

A system has a sound generator ( 20 ) that generates superimposed sound to a sound to be manipulated. An error sensor ( 50 ) measures sound and outputs a corresponding feedback signal (e′(n)). A signal generator ( 91 ) generates a sound signal (y(n)). A controller ( 92 ) generates a control signals (λ 1 (n)) and (λ 2 (n)). The adder ( 94 ) subtracts one control signal (λ 2 (n)) from the feedback signal (e′(n)) and outputs a modified feedback signal (en(n)) to the signal generator ( 91 ). A weighter ( 95 ) weights the sound signal (y(n)) with the control signal (λ 1 (n)) and outputs the weighted sound signal (y′(n)). The generated sound signal (y(n)) is a function of the modified feedback signal (e(n)). The controller ( 92 ) generates the control signals (λ 1 (n), λ 2 (n)) such that a value of the amplitudes of the feedback signal (∥e′(n)∥) corresponds to a predefinable value (Δ).

First claim

What is claimed is:

1. A system for actively influencing sound, the system comprising:
a sound generator configured to generate sound when an audio signal is sent to the sound generator and to superimpose the sound generated by the sound generator to a sound to be manipulated;
an error sensor configured to measure superimposed sound, which is obtained from the superimposition of the sound generated by the sound generator to the sound to be manipulated and to output a corresponding feedback signal;
a signal generator configured to generate and output a sound signal;
a controller configured to generate a first control signal and a second control signal;
an adder configured to subtract the second control signal from the feedback signal and to output a modified feedback signal, obtained, to the signal generator; and
a weighter configured to weight the sound signal outputted by the signal generator with a first control signal generated by the controller and to output a weighted sound signal to generate the audio signal;
wherein the signal generator is configured to generate the sound signal as a function of the modified feedback signal; and
wherein the controller is configured to generate the first and second control signals such that the value of the amplitudes of the feedback signal corresponds to a predefinable value.

2. A system in accordance with claim 1 ,
wherein the controller is configured to generate the first and second control signals with the use of a basic control signal, wherein the basic control signal represents a value from a sequence of rational numbers greater than or equal to zero,
wherein the basic control signal corresponds to a quotient of the predefinable value to a value of the amplitudes of the signal generated by the sound generator if the value of the amplitudes of the signal generated by the sound generator is greater than a threshold value greater than zero, and
wherein the basic control signal corresponds to a predefined maximum if the value of the amplitudes of the signal generated by the sound generator is lower than or equal to the threshold value.

3. A system in accordance with claim 2 , wherein the controller is configured to generate the first control signal from the difference from one and the basic control signal.

4. A system in accordance with claim 2 , wherein the controller is configured to generate the second control signal from the product of the basic control signal and a signal generated by the sound generator at an earlier time.

5. A system in accordance with claim 4 , wherein the earlier times of the signal generated by the sound generator precede the basic control signal by one internal clock frequency or multiples of an internal clock frequency of the signal generator.

6. A system in accordance with claim 2 , wherein the controller is configured to determine the signal generated by the sound generator by convoluting a transfer function of the sound generator with the weighted sound signal weighted by the weighter.

7. A system in accordance with claim 6 , wherein the controller is configured to use an estimated transfer function which is stored in the controller, instead of the transfer function of the sound generator, in order to obtain an estimate for the signal generated by the sound generator.

8. A system in accordance with claim 1 , wherein the generator is further configured to receive an input wave vector, which input wave vector depends on the sound to be manipulated, and to generate the sound signal as a function of the input wave vector.

9. A system in accordance with claim 8 , wherein the input wave vector is representative of at least one of the following speed of rotation or engine load or torque of an engine, which generates the sound to be manipulated,
an accelerator position or an accelerator gradient, wherein the accelerator controls an engine, which generates the sound to be manipulated,
a state of a clutch or a transmission, which are connected to an engine, which generates the sound to be manipulated,
a mode of operation of an engine, which generates the sound to be manipulated,
a voltage of a battery connected to an engine, which generates the sound to be manipulated, and
an operating state of an engine, which generates the sound to be manipulated.

10. A system in accordance with claim 8 ,
further comprising a microphone, which measures the sound to be manipulated and outputs a measured signal corresponding to the measured sound to be manipulated, wherein the signal generator is further configured to generate the sound signal by taking into account the measured signal, which is outputted by the microphone; and/or
a user interface which is configured to receive a user input, wherein the signal generator is further configured to generate the sound signal by taking into account the user input, which is received via the user interface and/or
wherein the signal generator can be connected to an engine control of an engine and is configured to generate the sound signal by taking into account signals that are received from the engine control.

11. A motor vehicle comprising:
an internal combustion engine with an engine control; and a system comprising:
a sound generator configured to generate sound when an audio signal is sent to the sound generator and to superimpose the sound generated by the sound generator to a sound to be manipulated;
an error sensor configured to measure superimposed sound, which is obtained from the superimposition of the sound generated by the sound generator to the sound to be manipulated and to output a corresponding feedback signal;
a signal generator configured to generate and output a sound signal;
a controller configured to generate a first control signal and a second control signal;
an adder, configured to subtract the second control signal from the feedback signal and to output a modified feedback signal obtained to the signal generator; and
a weighter, configured to weight the sound signal outputted by the signal generator with a first control signal generated by the controller and to output a weighted sound signal to generate the audio signal;
wherein the signal generator is configured to generate the sound signal as a function of the modified feedback signal; and
wherein the controller is configured to generate the first and second control signals such that the value of the amplitudes of the feedback signal corresponds to a predefinable value,
wherein the control is connected to at least one of the signal generator and the controller and is configured to determine the at least one of a speed of rotation, an engine load and a torque of the internal combustion engine and to output same as an input wave vector to the signal generator and/or controller.

12. A method for actively influencing sound, having the steps of:
generating a sound signal;
measuring a superimposed sound, which is obtained from the superimposition of sound generated as a function of the sound signal to a sound to be manipulated in order to obtain a corresponding feedback signal;
generating a basic control signal, wherein the basic control signal represents a value of a sequence of rational numbers greater than or equal to zero, wherein the basic control signal corresponds to a quotient of a predefinable value to a value of the amplitudes of a signal generated by a sound generator, if the value of the signal generated by the sound generator is greater than a threshold value greater than zero, and wherein the basic control signal corresponds to a predefined maximum if the value of the amplitudes of the signal generated by the sound generator is lower than or equal to the threshold value

Assignees

• Eberspaecher Exhaust Tech Gmbh

Inventors

• Buganza Federico

Classifications

• G10K2210/3014

  Adaptive noise equalizers [ANE], i.e. where part of the unwanted sound is retained · CPC title

• G10K2210/112

  Ducts · CPC title

• G10K2210/3026

  Feedback · CPC title

• G10K2210/12822

  Exhaust pipes or mufflers · CPC title

• G10K2210/30232

  Transfer functions, e.g. impulse response · CPC title