JP4539634B2 - Engine sound processing device - Google Patents

Description

  The present invention relates to an engine sound processing apparatus that processes engine sound and the like collected in a vehicle and outputs the processed engine sound.

  In recent years, there has been a demand for vehicles that emit less engine sound to the outside from the viewpoint of noise prevention. On the other hand, there is also a demand for enjoying powerful engine sounds in the vehicle. Therefore, as technical means for meeting such demands, various engine sound processing apparatuses have been proposed that pick up engine sound with a microphone in a vehicle, process it, and emit the sound into the vehicle interior. As this type of engine sound processing apparatus, there is one that picks up engine sound, amplifies it with a fixed gain such as 2 or 3 times, and emits the sound into the passenger compartment (hereinafter referred to as “first prior art”). "). As another engine sound processing apparatus, there is one that picks up engine sound, amplifies it with a gain proportional to the accelerator opening, and emits the sound into the passenger compartment (hereinafter referred to as “second prior art”). Called).

  By the way, when the driver performs a driving operation of depressing the accelerator to increase the speed of the vehicle, for example, the engine sound generated by the vehicle changes. In this sense, it can be said that the engine sound is a response from the vehicle side to the driving operation. The driver can feel the response of the driving operation of depressing the accelerator from the change (that is, response) of the engine sound that can be heard by his / her ear. Therefore, in order to make the driver perform a comfortable driving, it is extremely important to generate an engine sound that provides an appropriate response for the driver. In the first prior art described above, the collected engine sound is amplified with a fixed gain and emitted. Here, since the engine sound collected in the vehicle reflects the driving operation, even if this engine sound is amplified with a fixed gain and emitted into the passenger compartment, the emitted engine sound is emitted. Serves as a response. However, the degree of the response of the engine sound cannot be emphasized from the original engine sound of the vehicle, for example, the volume changes more sensitively to changes in the accelerator opening or the vehicle speed than the original engine sound of the vehicle. The second prior art described above can be said to add a response corresponding to the driving operation to the engine sound inherent in the vehicle in that the volume of the engine sound is proportional to the accelerator opening. However, the aspect of the change in the volume of the engine sound obtained by the second prior art is not suitable as a response to the depression of the accelerator, and gives the driver an artificial and unnatural impression. In addition, since the accelerator opening often changes sharply, there is a problem in that the engine sound becomes awkward if the volume of the engine sound emitted into the vehicle interior is changed according to the accelerator opening. .

  The present invention has been made in view of the above-described circumstances, and provides an engine sound processing device that can process and reflect sound generated from engine sound that has been collected or reproduced. The purpose is to provide.

The present invention includes a driving state detection unit that detects a driving state of a vehicle, a driving state parameter acquisition unit that outputs a driving state detected by the driving state detection unit as a driving state parameter, and a time differential value of the driving state parameter. Control parameter generation means for calculating an engine sound processing control parameter based on the time differential value, and collecting the engine sound generated in the vehicle, or a storage medium at a speed synchronized with the rotation of the engine of the vehicle The engine sound signal acquisition means for acquiring the engine sound signal by reproducing the engine sound waveform from the engine, the engine sound processing means for processing the engine sound signal based on the engine sound processing control parameter, and the engine sound signal An engine that outputs the engine sound signal processed by the processing means to the vehicle as sound To provide an engine sound processing apparatus characterized by comprising a sound output means.
According to this invention, the engine sound processing control parameter is calculated based on the time differential value of the driving state parameter, and the processing based on the engine sound processing control parameter is performed on the engine sound signal, so that the driving operation is reflected. An engine sound signal is obtained.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of an engine sound processing apparatus according to an embodiment of the present invention. This engine sound processing device is a device that processes engine sound picked up by a vehicle and outputs the processed sound to the passenger compartment. In FIG. 1, a driving state parameter acquisition unit 10 includes driving state detection means such as an engine speed sensor, an accelerator opening sensor, and a vehicle speed sensor (all not shown) via an in-vehicle network 11 such as a LAN (Local Area Network). It is connected to the. The driving state parameter acquisition unit 10 acquires engine speed, accelerator opening, vehicle speed, and the like from the driving state detection means via the in-vehicle network 11, and engine speed data D1, accelerator opening data D2, vehicle speed data D3, etc. Is output as the operation state parameter.

  The switch unit 20, the parameter processing units 31 to 34, and the synthesis unit 40 are engine speed data D1, accelerator opening degree data, and engine sound processing control parameters used to control engine sound processing under the control of the control unit 100. A control parameter generating means for generating from driving state parameters such as D2 and vehicle speed data D3 is configured.

  More specifically, switch control information is given to the switch unit 20 from the control unit 100. This switch control information specifies what is selected for use in the synthesis of engine sound processing control parameters from among various operation state parameters, and supplies the selected operation state parameters to any of the parameter processing units 31 to 34. This information specifies what should be done. The switch unit 20 selects an operation state parameter designated by the switch control information from among operation state parameters such as engine speed data D1, accelerator opening data D2, vehicle speed data D3, and the like among the parameter processing units 31 to 34. This is supplied to the parameter processing unit specified by the switch control information. In the present embodiment, the operation state parameter instructed to be selected by the switch control information is not limited to one type, and there are cases in which selection of a plurality of types of operation state parameters is instructed. Further, the supply destination of the selected operation state parameter is not limited to one place, and a plurality of parameter processing units are designated by the switch control information as one type of operation state parameter supply destination, for example, the parameter processing units 31 and 33. In some cases.

The parameter processing units 31 and 32 are devices that perform a time differential operation of the operation state parameter given through the switch unit 20 and output a time differential value of the operation state parameter. Further, the parameter processing units 33 and 34 calculate a time differential value by performing a time differential operation of the operation state parameter given through the switch unit 20, and further, the calculated time differential value sequence has a predetermined time constant. It is an apparatus that generates and outputs envelope data indicating an envelope of a time differential value sequence by performing a low-pass filter process or by calculating a moving average of the calculated time differential value sequence. Here, envelope generation control information is given from the control unit 100 to the parameter processing unit 33 or 34 that generates envelope data. The envelope generation control information is information that specifies which of the following three methods should be used to generate envelope data.
a. Method of generating envelope data using both positive and negative time differential values b. Method of generating envelope data using only positive time derivative values c. Method for Generating Envelope Data Using Only Negative Time Differential Value The parameter processing unit 33 or 34 that generates envelope data generates envelope data by a method specified by the envelope generation control information.

The composition control information is given to the composition unit 40 from the control unit 100. The synthesis control information is obtained by performing any synthesis operation on the time differential value of the operating state parameter or the envelope data of the time differential value of the operating state parameter output from the parameter processing units 31 to 34 to determine the engine sound processing control parameter. Is information that specifies whether to synthesize. The synthesizing unit 40 synthesizes engine sound processing control parameters by performing a synthesizing operation designated by the synthesis control information on each data output from the parameter processing units 31 to 34. There are the following three types of modes of the synthesis operation specified by the synthesis control information.
a. One type of time differential value or envelope data is output as it is as an engine sound processing control parameter.
b. Engine sound processing control parameters are synthesized by weighted addition of multiple types of time differential values or envelope data.
c. Engine sound processing control parameters are synthesized by weighted multiplication of multiple types of time differential values or envelope data.

  In this embodiment, many types of methods are prepared as methods for generating the final engine sound processing control parameters from the operating state parameters, but these methods can be categorized as follows. .

<Method 1>
In this method, one type of operation state parameter (for example, engine speed data D1) is given to the parameter processing unit 31 via the switch unit 20. Then, the synthesizing unit 40 outputs the time differential value of the operation state parameter output from the parameter processing unit 31 as it is as the engine sound processing control parameter.

<Method 2>
In this method, one type of operation state parameter is given to the parameter processing unit 33 via the switch unit 20. Then, the synthesizing unit 40 outputs the envelope data of the time differential value (both positive / negative / only positive / only negative) of the operation state parameter output from the parameter processing unit 33 as it is as the engine sound processing control parameter.

<Method 3>
In this method, one type of operation state parameter is given to the parameter processing units 31 and 33 via the switch unit 20. The synthesizing unit 40 includes the time differential value of the operating state parameter output from the parameter processing unit 31 and the time differential value of the operating state parameter output from the parameter processing unit 33 (both positive / negative / only positive / only negative). Envelope data is synthesized and output as engine sound processing control parameters. As a synthesis method, a method in which a predetermined weight is added to the time differential value of the operating state parameter and the envelope data of the time differential value of the operating state parameter, and the time differential value of the operating state parameter and the time differential of the operating state parameter are added. There is a method of multiplying the value envelope data with a predetermined weight. Which method is used for synthesis is determined by the synthesis control information given from the control unit 100 to the synthesis unit 40.

<Method 4>
In this method, different operating state parameters (for example, engine speed data D1 and accelerator opening degree data D2) are given to the parameter processing units 31 and 33 via the switch unit 20. Then, the synthesizing unit 40 includes the time differential value of the operating state parameter (for example, engine speed data D1) output from the parameter processing unit 31 and the operating state parameter (for example, accelerator opening data D2) output from the parameter processing unit 33. ) And the time differential value envelope data are synthesized and output as engine sound processing control parameters. There are weighted addition and weighted multiplication in the synthesis method.

<Method 5>
In this method, different operating state parameters (for example, engine speed data D1 and accelerator opening data D2) are given to the parameter processing units 33 and 34 via the switch unit 20. Then, the synthesizing unit 40 includes envelope data of the time differential value of the operating state parameter (for example, engine speed data D1) output from the parameter processing unit 33 and the operating state parameter (for example, accelerator opening) output from the parameter processing unit 34. The time differential value envelope data of the degree data D2) is synthesized and output as an engine sound processing control parameter. There are weighted addition and weighted multiplication in the synthesis method.

  In FIG. 1, a sound collection unit 50 is a device that collects engine sound generated in a vehicle with a microphone and outputs an engine sound signal. In a preferred embodiment, intake sound, engine explosion sound, exhaust sound, mechanical sound, and other sounds are selected as components of engine sound, and a plurality of microphones are provided at each location suitable for collecting each of these engine sound components. The engine sound signal is generated by mixing the output signals of the microphones. The engine sound processing unit 60 processes the engine sound signal obtained from the sound collection unit 50 based on the engine sound processing control parameter output from the synthesis unit 40, specifically, the sound pressure based on the engine sound processing control parameter. It is a device that performs control and outputs. The engine sound output unit 70 is a device that emits an engine sound signal that has been processed by the engine sound processing unit 60 into the vehicle interior as a sound, and includes an amplifier and a speaker. The engine sound output unit 70 may use an in-vehicle audio device such as a car stereo.

  The control unit 100 is a device that controls the entire engine sound processing apparatus. A memory 110 and an operation display unit 120 are connected to the control unit 100. The operation display unit 120 is arranged at a position in front of the driver in the passenger compartment, and is a display unit such as a liquid crystal display panel that provides various display information to the driver and a push for receiving commands and information from the driver. It consists of controls such as buttons. The memory 110 stores a control program used for controlling the engine sound processing apparatus and various control data. As already described, in this embodiment, a plurality of types of methods for generating the engine sound processing control parameter from the operation state parameter are prepared. The memory 110 stores a control information set prepared for each of these methods. Here, each control information set includes switch control information, envelope generation control information, and synthesis control information. Note that the envelope generation control information is included in the control information set only when the parameter processing unit 33 or 34 generates envelope data. The control unit 100 refers to these control information sets and controls the switch unit 20, the parameter processing units 31 to 34, and the synthesis unit 40.

  Next, the operation of this embodiment will be described. When a method for generating the engine sound processing control parameter from the operation state parameter is designated by the operation of the operation display unit 120, the control unit 100 designates the method designated from each control information set stored in the memory 110. The control information set corresponding to is selected and read. Then, the switch control information in the read control information set is supplied to the switch unit 20, and the synthesis control information is supplied to the synthesis unit 40. When the read control information set includes envelope generation control information, the control unit 100 supplies the envelope generation control information to the parameter processing unit 33 or 34 that generates envelope data.

  When driving of the vehicle is started, the driving state parameter acquisition unit 10 acquires the engine speed, the accelerator opening, the vehicle speed, and the like via the in-vehicle network 11, and the engine speed data D1, the accelerator opening data D2, the vehicle speed. Output as operation state parameters such as data D3.

  The switch unit 20 selects an operation state parameter specified by the switch control information from these operation state parameters, and supplies the selected parameter to the parameter processing unit specified by the switch control information among the parameter processing units 31 to 34.

  Here, when the operation state parameter is given to the parameter processing unit 31 or 32, the parameter processing unit 31 or 32 to which the operation state parameter is given performs time differentiation calculation of the operation state parameter, and the time differential value is obtained. Output. Further, when the operation state parameter is given to the parameter processing unit 33 or 34, the parameter processing unit 33 or 34 to which the operation state parameter is given calculates the time differential value by performing the time differentiation operation of the operation state parameter. In addition, envelope data of a time differential value sequence is generated and output. At this time, envelope data is generated from both positive and negative time differential values, positive time differential values, or negative time differential values in accordance with the envelope generation control information.

  The synthesizing unit 40 synthesizes engine sound processing control parameters by performing synthesis operation designated by the synthesis control information given from the control unit 100 on each data output from the parameter processing units 31 to 34. The engine sound processing unit 60 performs sound pressure control on the engine sound signal obtained from the sound collection unit 50 based on the engine sound processing control parameter. The engine sound output unit 70 outputs an engine sound signal that has undergone this sound pressure control as sound to the passenger compartment.

  Next, the effect of this embodiment will be described with reference to FIGS. 2 to 4 show the sound pressure of the engine sound picked up by the sound pickup unit 50 when the vehicle travels in a certain section, the accelerator opening of the vehicle detected by the driving state detecting means, and the engine speed. It is a graph shown respectively.

  Here, if engine sound signal processing (in this example, sound pressure control) is performed using the accelerator opening as it is as an engine sound processing control parameter, the sound pressure of the engine sound signal before and after processing is as shown in FIG. It becomes. If engine sound signal processing (in this example, sound pressure control) is performed using the engine speed as it is as an engine sound processing control parameter, the sound pressure of the engine sound signal before and after processing is as shown in FIG. Become. As shown in these figures, when the accelerator opening and the engine speed are used as they are for the processing of the engine sound signal, the sound pressure of the engine sound signal only increases as a result of the processing. It can't be said that the engine sound signal has been emphasized.

  FIG. 7 is a graph showing the time differential value obtained by performing the time differential calculation of the engine speed in FIG. As can be seen from FIG. 7, the time differential value of the engine speed is time-series data reflecting an accelerator operation for increasing or decreasing the engine speed. FIG. 8 is a graph showing envelope data generated from both positive and negative time differential values of the engine speed shown in FIG. The envelope data is time-series data having a relatively gentle undulation, with a rapid change in the time differential value of the engine speed. When engine sound signal processing (in this example, sound pressure control) is performed using the envelope data of FIG. 8 as an engine processing control parameter, the sound pressure of the engine sound signal before and after processing is as shown in FIG. In this case, the sound pressure change of the engine sound signal after processing reflects the accelerator operation. However, since the envelope data generated from the time differential values of both the engine speed and the engine speed are used, the sound pressure of the engine sound signal after processing fluctuates in both positive and negative directions with respect to the original sound pressure. There is a difficulty in changing pressure.

  FIG. 10 is a graph showing envelope data generated only from a positive time differential value among the time differential values of the engine speed shown in FIG. FIG. 11 is a graph showing the sound pressure of the engine sound signal before and after processing when engine sound signal processing (sound pressure control in this example) is performed using the envelope data of FIG. 10 as an engine processing control parameter. It is. In this case, the change in the sound pressure of the engine sound signal obtained by processing reflects the accelerator operation very well. The engine speed was used even if the accelerator opening was used instead of the engine speed, and the envelope data generated from only the positive time derivative of the accelerator opening was used as the engine sound processing control parameter. As in the case, an engine sound signal having a sound pressure change that reflects the accelerator operation very well is obtained. The same applies to the case where envelope data is generated from a negative time differential value instead of a positive time differential value.

  As described above, when the sound pressure control of the engine sound signal is performed using the envelope data of the positive or negative time differential value such as the engine speed as the engine sound processing control parameter, the engine sound in which the response to the accelerator operation is emphasized. A signal is obtained. However, there are various preferences regarding the degree and mode of response emphasis. For example, there are users who prefer a response that is more sensitive to accelerator operation than that shown in FIG. It is considered that there are some users who feel insensitive to operations. According to the present embodiment, various methods for obtaining the engine sound processing control parameter from the operation state parameter are prepared, and the user can select a desired one from them, so that the response enhancement is related. It can meet various demands.

Although one embodiment of the present invention has been described above, other embodiments are possible for the present invention. For example:
(1) In the above embodiment, the engine sound is picked up, processed and reproduced from the engine sound output unit 70. However, instead of actually collecting the engine sound in this way, the engine sound waveform data is stored in the memory in advance, and the waveform data is read from the memory at a reading speed corresponding to the engine speed, and the engine sound signal is The engine sound signal may be reproduced and processed in the same manner as in the above embodiment.
(2) In the above embodiment, the engine sound processing unit 60 controls the sound pressure of the engine sound signal based on the engine sound processing control parameter. However, processing other than sound pressure control, for example, adding noise to the engine sound signal, Processing may be performed such that the noise level at that time is controlled by engine sound processing control parameters.
(3) In the above embodiment, the engine sound processing apparatus is configured to be able to execute any of the above methods 1 to 5, but only one type of the above methods 1 to 5 or only a limited type of method is executed. It is good also as a possible structure.
(4) In the above embodiment, the engine sound processing control parameters are generated using a part of the operation state parameters. However, the number of parameter processing units 31 to 34 is increased, and the engine sound processing control is performed using all the operation state parameters. A parameter may be generated.

It is a block diagram which shows the structure of the engine sound processing apparatus which is one Embodiment of this invention. It is a graph which shows the sound pressure of the engine sound collected when the vehicle drive | worked a certain area. It is a graph which shows the accelerator opening degree of the vehicle which drive | works the same area. It is a graph which shows the engine speed of the vehicle which drive | works the same area. It is a graph which shows the sound pressure of the engine sound signal before and after a process at the time of processing an engine sound signal, using the accelerator opening as it is as an engine sound process control parameter. It is a graph which shows the sound pressure of the engine sound signal before and after a process at the time of processing an engine sound signal, using the same engine speed as an engine sound process control parameter as it is. It is a graph which shows the time differential value obtained by performing the time differential calculation of the engine speed in FIG. It is a graph which shows the envelope data produced | generated from the time differential value of both positive and negative of the engine speed shown in FIG. It is a graph which shows the sound pressure of the engine sound signal before and after a process at the time of processing an engine sound signal using the envelope data shown in FIG. 8 as an engine process control parameter. It is a graph which shows the envelope data produced | generated only from the positive time differential value among the time differential values of the engine speed shown in FIG. It is a graph which shows the sound pressure of the engine sound signal before and after a process at the time of processing an engine sound signal using the envelope data shown in FIG. 10 as an engine process control parameter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Control part, 110 ... Memory, 120 ... Operation display part, 10 ... Driving state parameter acquisition part, 11 ... In-vehicle network, 20 ... Switch part, 31-34 ... Parameter processing part, 40 ... ... synthesizer, 50 ... sound collecting part, 60 ... engine sound processing part, 70 ... engine sound output part.

Claims (6)

Driving state detection means for detecting the driving state of the vehicle;
Driving state parameter acquisition means for outputting the driving state detected by the driving state detection means as a driving state parameter;
Control parameter generating means for calculating a time differential value of the operating state parameter and generating an engine sound processing control parameter based on the time differential value;
Engine sound signal acquisition means for acquiring an engine sound signal by collecting engine sound generated in the vehicle or reproducing an engine sound waveform from a storage medium at a speed synchronized with the rotation of the engine of the vehicle;
Engine sound processing means for processing the engine sound signal based on the engine sound processing control parameters;
An engine sound output means for outputting to the vehicle as a sound engine sound signal is processed by the engine sound machining unit,
With
The control parameter generating means includes parameter processing means for calculating a time differential value from a plurality of types of operation state parameters, and combines the time differential values of the plurality of types of operation state parameters calculated by the parameter processing means to generate engine sound. An engine sound processing device that generates a processing control parameter . The said control parameter production | generation means produces | generates the said engine sound processing control parameter by carrying out weighted addition of the time differential value of the multiple types of movement state parameter calculated by the said parameter processing means, The said engine sound processing control parameter is produced | generated. Engine sound processing device. The said control parameter production | generation means produces | generates the said engine sound process control parameter by carrying out weight multiplication of the time differential value of the several types of exercise state parameter calculated by the said parameter process means. Engine sound processing device.   Driving state detection means for detecting the driving state of the vehicle;
  Driving state parameter acquisition means for outputting the driving state detected by the driving state detection means as a driving state parameter;
  Control parameter generating means for calculating a time differential value of the operating state parameter and generating an engine sound processing control parameter based on the time differential value;
  Engine sound signal acquisition means for acquiring an engine sound signal by collecting engine sound generated in the vehicle or reproducing an engine sound waveform from a storage medium at a speed synchronized with the rotation of the engine of the vehicle;
  Engine sound processing means for processing the engine sound signal based on the engine sound processing control parameters;
  Engine sound output means for outputting the engine sound signal processed by the engine sound processing means as sound in the vehicle;
  With
  The control parameter generation means includes first parameter processing means for calculating envelope data indicating an envelope of a time differential value of the operating state parameter, and based on the envelope data calculated by the first parameter processing means Generate engine sound processing control parameters
  An engine sound processing device characterized by that. The first parameter processing means calculates time differential value envelope data from a plurality of types of operation state parameters, and the control parameter generation means synthesizes time differential value envelope data of a plurality of types of operation state parameters. The engine sound processing apparatus according to claim 4, wherein the engine sound processing control parameter is generated. The control parameter generation means includes second parameter processing means for calculating a time differential value of the operating state parameter, and is calculated by the envelope data calculated by the first parameter processing means and the second parameter processing means. The engine sound processing apparatus according to claim 4, wherein the engine sound processing control parameter is generated by synthesizing the obtained time differential values.

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