JPS62175238A - Onboard type sound source approach informing device - Google Patents

Abstract

PURPOSE:To know data of necessary sound outboard of a vehicle even though acoustic equipment is operated while all vehicle windows are closed, by discriminating sound whether or not it comes from a sound source of the kind which is previously registered when the sound source approaches, thereby sound outboard of the vehicle is reproduced so that it may be heard in the vehicle. CONSTITUTION:There is provided a sound-electric converter 1 for converting sound outboard of a vehicle into an electrical signal, and the characteristic of an output signal is extracted by band-pass filters 2. Further, there is provided a memory circuit 5 for storing therein the characteristic of each of various kinds of sound sources, as to the frequency distributions of intensity of the sound generated from several kinds of sound sources to be informed, and the time variations thereof. Further, a discriminating circuit 6 compares the characteristics of the sound sources stored in the circuit 5 with output signals from the filters 2, and therefore, discriminates whether the sound comes from a sound source which is one of the kind of sounds to be informed or not. Further, a switch is a reproducing circuit 7 is opened and closed under control in accordance with an output signal from then discriminating circuit 6, and therefore, the sound outboard of the vehicle is reproduced when the sound source approaches, and is transmitted into the vehicle by means of a speaker 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle-mounted sound source approach notification device that notifies the driver of a vehicle of the approach of various sound sources outside the vehicle.

[Conventional technology]

Recently, devices have been developed that detect horn sounds, sirens of emergency vehicles, warning sounds at railroad crossings, etc., convert these sounds into light or vibration stimulation, and notify the driver so that people with hearing loss can drive a car. being developed.

Fig. 7 is a spectrodaram for various sound sources, and Fig. 8 is a block diagram of a conventional in-vehicle sound source approach device. The circuit 4 is a notification device.

Next, the operation will be explained. In the spectrogram in Figure 7, a is the car horn sound, b is the pass horn sound, and C is the emergency car horn sound! i shows the spectrogram of the siren sound of a rickshaw, d shows the spectrogram of the warning sound of a railroad crossing, and e shows the spectrogram of surrounding traffic noise. A - d have sharp peaks in specific frequency bands, and are clearly different from e, traffic noise. In the conventional device shown in FIG. 8, sounds from outside the vehicle during driving are always converted into electrical signals by an acousto-electrical transducer 1 and transmitted to a group of band-pass F-wave devices 2. The characteristics of this bandpass wave transducer '8+2 are the number of channels and the center so that all peak frequencies above a certain intensity are included in the pass band in the spectrogram of source sounds such as horn sounds, sirens, and railroad crossing warning sounds. The frequency, Q value, etc. are set in advance, and when a sound source of the type to be reported approaches, a strong signal is output from a plurality of channels among the channels of the band-pass offshore wave device group 2. A threshold regarding the intensity is set in advance in the verification circuit 3, and when an intensity equal to or higher than the threshold is observed in at least one of the channels during luck/run, the verification circuit 3 transmits the information to the notification device 4.
Outputs a signal to. The notification device 4 notifies the driver that at least one of the sound sources of the 511fi class is approaching by lighting a lamp or by the reaction of a vibrator brought into contact with the driver's body.

[Problem that the invention seeks to solve]

Since the conventional in-vehicle sound source proximity reporting device is configured as described above, it has had problems such as not being able to clearly report information about the uniqueness of the sound source.

In addition, even for people with normal hearing, there are safety issues such as closing the car windows and using audio equipment, making it difficult to hear the horn and other warning sounds, and delaying the time it takes to know when another vehicle is approaching. Ta.

This invention was made to solve the above-mentioned problems, and it not only makes it possible to distinguish the type of sound source, but also makes it easier for people with normal hearing to drive, even if they close the car window and use an acoustic device. The purpose is to develop an in-vehicle sound source approach notification device that can obtain acoustic information.

[Means for solving problems]

The in-vehicle sound source approach notification device according to the present invention includes an acoustoelectric transducer attached to the outside of the vehicle body, a circuit for extracting the characteristics of the output signal of this converter, and a process for processing the output signal of this circuit to determine the sound source. This circuit is constructed using a circuit and a switch that opens and closes based on the output signal to reproduce external sound into the vehicle when the sound source approaches.

[For production]

The in-vehicle sound source d nearby notification device of the present invention collects external sounds from the vehicle using an acousto-electrical transducer, converts this into an electrical signal, extracts all the characteristics of the sound source, and reports that one type of sound source is approaching. Based on this determination result, it is possible to reproduce external sounds into the vehicle when the sound source approaches.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, 1 is an acousto-electrical transducer that converts the external sound of the vehicle into an electrical signal, 2 is a group of band-pass b-wavelength converters that extracts the characteristics of the output signal of this converter 1, and 5 is a group of various types of signals to be reported. A memory circuit 6 stores the characteristics of each sound source by examining the frequency strong inverse component of the sound emitted by the sound source; l]j and its temporal change in advance; A discrimination circuit 7 compares the characteristics of each stored sound source to determine whether it is one of the types of sound sources reported, and 7 includes a switch that opens and closes based on the output signal of the discrimination circuit 6; A reproduction circuit 8 is a speaker that reproduces sound outside the vehicle into the interior of the vehicle when the sound source approaches.

Next, the operation will be explained. Sounds from outside the vehicle during driving are always converted into electrical signals by the acousto-electrical transducer 1 and transmitted to the band-pass F wave device group 2. The characteristics of the bandpass door wave device group 2 are the number of channels, center frequency, Q value, etc. so that the pass band includes all peak frequencies that are above a certain threshold in the spectrogram of the type of source sound to be reported, such as a horn sound. Set in advance. Further, a rectifier circuit is provided for each channel at the final stage of this circuit so that an output proportional to the spectral intensity can be obtained. By setting the characteristics of the bandpass F wave device group 2 in this way, it will be reported that when one type of sound source among the sound sources approaches, each channel will receive the strong 1ν distribution and 1
] The ξ turn of the change between ♀ is output. The discrimination circuit 6 discriminates whether or not the sound source is one of the reported sound sources based on the output signal of the organ group 2.

The discrimination circuit 6 operates in two modes: a registration mode and a discrimination mode. In Muyu recording mode, the sound source sound for the weight that is reported by the horn sound temple! θ''f1. is extracted through acoustoelectric transducer 1 and bandpass filter #2.

The discrimination circuit 6 samples this characteristic No. 1d at equal time intervals. The sampling time length is set to be longer than the maximum period of the sound source sound. By dividing the number of sampling data at this time, the number of channels of band-pass P-wave device group 2 is determined as N1 sound source sound k (k=1).

2...knvm) for the i-th channel (i=1
, 2...N) output from the jth (j=1.2・
... L) sampling data is Si, j, k, then the normalized pattern "/R1, j," is: R;, j, ni = S;, J, ni/宕〒[Si, j, To:
)...In (1), use each '+J as a variable and set Si
, j, is calculated for each k. The discrimination circuit 6 calculates the normalized notation R1, j, k for each source sound k and stores it in the storage circuit 5.

On the other hand, in the discrimination mode, the characteristics of the sound outside the vehicle are extracted through the acoustoelectric transducer 1 and the group of band-pass filters 2, and the discrimination circuit 6 samples at the same time intervals as in the registration mode. However, in the discrimination mode, the number of sampling data is 2L. i-th channel (i=1.2...N)
If the sampling data of the j-th (j=1.2...2L) outside vehicle sound output from
It is expressed as aX[Si,j]·=(2)′+J. Here, maX[:si,j:] is s3
．． The maximum value of Si+J is calculated using each i and j as variables in jvc.

Hereinafter, the operation of the discrimination circuit 6 in the discrimination mode will be explained according to the flowchart shown in FIG.

The 2L sampled data of the sound outside the vehicle are normalized by the above equation (2). Next, the normalized patterns Ri, j, k (f”=1.2
-N), (j=1.2-L), (k=1,2
- knvm ) and the normalized pattern of external sound Xi, j (i
=1, 2...N).

(J = 1 + 2...2L). In Figure 4, we first calculate the 9A similarity with the first source sound as "
1", set it to = 1, and then sequentially set it to 1 (+1→) to calculate each sound source k (k=1.2...knv
m).

As schematically shown in FIG. 3, in general, the normalized turn RLJ+ of the sound source is a turn with a period Tl (repetition) with respect to j. On the other hand, when approaching the source sound, the normalized pattern Xi,j of the external sound also has a period Tk with respect to J.
is input with a temporal shift.

In order to correct this shift, in Fig. 2, from J=O to J+1
→J, Xi, j and R1 shown in FIG.
The similarity is calculated while shifting the patterns of j and k. The simplest example of expressing the degree of similarity is shown below.

Here, dJK represents the degree of similarity between the normalized pattern of the external sound and the normalized pattern of the source sound when the shift amount is J (J=0, 1...L). By equation (3), all J (J
= 0, 1 ・L) and k (k = 1, 2−
After calculating dJK for (knvm), the minimum value of these values is determined. When D is smaller than the preset threshold value THR, the discrimination circuit 6 determines that the sound source sound k (lc=l
, 2 . When 17'CD is greater than or equal to THR, it is determined that no sound source is approaching, and no signal is output to the reproduction circuit 7. Based on the discrimination circuit 6, the reproduction circuit 7 outputs the reproduced sound of the sound outside the vehicle when the sound source approaches to the speaker 8.
Output from After the discrimination circuit 6 finishes the above processing,
Input the sound outside the vehicle again and repeat the process shown in Fig. 3.

In the embodiment, a reproducing circuit 7 is provided as a reporting means, but a volume adjustment circuit for an in-vehicle audio device may also be provided. In this case, as shown in FIG. 4, when the discrimination circuit 6 determines that the sound source is approaching, it reduces the sound Mk of the operating in-vehicle audio equipment 9, and on the other hand, when it determines that the sound source is not approaching, it reduces the sound Mk based on the volume. The signal to be returned is output to the volume adjustment circuit 10. Then, based on this signal, the volume adjustment circuit 10 adjusts the volume of the audio equipment 9, and then adjusts the volume of the speaker 8.
Outputs acoustic sound from.

Further, as a reporting means, a mixing and reproducing circuit may be provided which mixes the sound of the in-vehicle audio equipment 9 and the sound outside the vehicle at a constant ratio and reproduces the mixture in the vehicle. In this case, as shown in FIG. 5, when the discrimination circuit 6 determines that the sound source is approaching, it mixes and reproduces a signal to mix the sound of the in-vehicle acoustics device 9 in operation and the sound outside the vehicle at a fixed ratio. Output to circuit 11. Further, when it is determined that the sound source is not approaching, a signal for reproducing only the sound of the audio equipment 9 is output to the mixing reproduction circuit 11. Based on this signal, the mixing reproducing circuit 11 changes the mixing state.
In example 1, the switch 12 is turned on when the discrimination circuit 6 determines that the sound source is approaching, and is turned off when it is determined that the sound source is not approaching.

The mixing ratio of the output signals of the cut acoustoelectric transducer 1 and the in-vehicle audio equipment 9 is set by the value of the resistor 13.14. The mixed signal passes through the amplifier 15 and is output as sound from the speaker 8 in the car.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to hear outside sounds inside the car when a pre-registered type of sound source approaches, so that people with hearing loss can distinguish the type of sound source from outside the car, and even people with normal hearing can listen to sounds from outside the car. Even if you close the door and use the audio equipment, you can obtain the information on external sounds necessary for driving, which has the effect of improving safety when driving a car.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an in-vehicle sound source approach reporting device according to an embodiment of the present invention, FIG. 2 is a flowchart showing the processing procedure of the discrimination mode, and FIG. 3 is a diagram showing temporal changes in the spectrum of the sound source. 4 and 5 are block diagrams of an in-vehicle sound source approach notification device showing other embodiments, FIG. 6 is a mixing reproduction circuit diagram, FIG. 7 is a spectrogram of various sound source sounds, and FIG. 8 is a conventional one. FIG. 2 is a block diagram of an in-vehicle sound source approaching notification device. 1... Acoustoelectric transducer, 2... Bandpass offshore transducer group,
5... Memory circuit, 6... Discrimination circuit, 7... Reproduction circuit, 8... Speaker, 9... Audio equipment, 10...
Volume adjustment circuit, 11...mixing reproduction circuit, 15...amplifier. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Masuo Oiwa 1st Figure 72 shows the rebellion Figure 2 Figure 3 @ 4th Figure 5 Figure 6 Figure 7 Figure 8 [2]! 23 Procedural amendment (voluntary) Showa month/day

Claims (3)

[Claims] (1) An in-vehicle sound source approach notification device for notifying the driver of the approach of various sound sources outside the vehicle includes an acousto-electrical transducer that is attached to the outside of the vehicle body and converts sounds from outside the vehicle into electrical signals; A feature extraction circuit that extracts the characteristics of the output signal of the converter, a discrimination circuit that processes the output signal of this extraction circuit to discriminate the sound source, and a switch that opens and closes based on the output signal of the discrimination circuit are used to detect sounds outside the vehicle when the sound source approaches. A vehicle-mounted sound source approach notification device characterized by comprising a reproduction circuit for reproducing the sound inside the vehicle. (2) The vehicle-mounted sound source approach notification device according to claim 1, further comprising a volume adjustment circuit that adjusts the volume of an operating in-vehicle audio device based on the output signal of the discrimination circuit. (3) A mixing and reproducing circuit that mixes the sound of the in-vehicle audio equipment operating when the sound source approaches and the sound outside the vehicle at a fixed ratio and reproduces the mixture inside the vehicle by means of a switch that opens and closes based on the output signal of the discrimination circuit. An in-vehicle sound source approach notification device according to claim 1.