Method for identifying sirens of priority vehicles and warning a hearing-impaired driver of the presence of a priority vehicle

Abstract

Disclosed is a device for identifying sirens of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle in an environment of his vehicle, including at least one sound receiver, a computing unit for analyzing the audio recording and a unit for comparing the frequencies of the audio recording with frequencies previously stored in storage of the computing unit as being associated with a siren of a given priority vehicle, and for doing so for each type of priority vehicle, and at least one visual and/or vibratory element for warning the driver when a presence of a priority vehicle is detected in an environment of the motor vehicle.

Claims

1. A method for identifying sirens of a plurality of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle of the plurality of priority vehicles in an environment of the motor vehicle, the method comprising: acquiring an audio recording of the environment; analyzing the audio recording comprising comparing the frequencies acquired from the audio recording with previously-stored frequencies associated with a siren of the at least one priority vehicle, for each type of the plurality of priority vehicles by taking into account at least one fundamental frequency of the siren with at least the first five harmonics of the at least one fundamental frequency; and warning the hearing-impaired driver that the at least one priority vehicle is driving in the environment of the motor vehicle when it is detected that frequencies of the siren of the at least one priority vehicle are present in the audio recording.

2. The method as claimed in claim 1, wherein the acquired frequencies are taken into account only when the amplitude of the acquired frequencies is higher than a minimum threshold.

3. The method as claimed in claim 2, wherein the warning comprises emitting a light signal in a field of view of the hearing-impaired driver.

4. The method as claimed in claim 2, wherein, for each siren of the plurality of priority vehicles, one or more fundamental frequencies specific to the respective siren are stored with an alternation and a number of cycles per minute of repetitions of the frequencies specific to the respective siren.

5. The method as claimed in claim 2, further comprising carrying out band-pass filtering with a pass band comprised between 400 Hz and 7 kHz on the audio recording before the analyzing.

6. The method as claimed in claim 1, wherein the warning comprises emitting a light signal in a field of view of the hearing-impaired driver.

7. The method as claimed in claim 6, wherein the light signal is emitted by one or more indicator lights.

8. The method as claimed in claim 7, wherein the warning indicates an origin of the siren with respect to the motor vehicle and the type of priority vehicle associated with the detected siren.

9. The method as claimed in claim 7, wherein, for each siren of the plurality of priority vehicles, one or more fundamental frequencies specific to the respective siren are stored with an alternation and a number of cycles per minute of repetitions of the frequencies specific to the respective siren.

10. The method as claimed in claim 6, wherein the warning indicates an origin of the siren with respect to the motor vehicle and the type of priority vehicle associated with the detected siren.

11. The method as claimed in claim 10, wherein, for each siren of the plurality of priority vehicles, one or more fundamental frequencies specific to the respective siren are stored with an alternation and a number of cycles per minute of repetitions of the frequencies specific to the respective siren.

12. The method as claimed in claim 6, wherein, for each siren of the plurality of priority vehicles, one or more fundamental frequencies specific to the respective siren are stored with an alternation and a number of cycles per minute of repetitions of the frequencies specific to the respective siren.

13. The method as claimed in claim 6, wherein the light signal is displayed on an instrument panel.

14. The method as claimed in claim 6, wherein the light signal is displayed as a text message displayed on a screen of an on-board computer of the motor vehicle.

15. The method as claimed in claim 1, wherein, for each siren of the plurality of priority vehicles, one or more fundamental frequencies specific to the respective siren are stored with an alternation and a number of cycles per minute of repetitions of the frequencies specific to the respective siren.

16. The method as claimed in claim 1, further comprising carrying out band-pass filtering with a pass band comprised between 400 Hz and 7 kHz on the audio recording before the analyzing.

17. The method as claimed in claim 1, wherein the warning comprises generating vibrations of a device of the motor vehicle that are transmitted to the hearing-impaired driver.

18. The method as claimed in claim 17, wherein the vibrations affect the seat or the steering wheel of the hearing-impaired driver.

19. A device for implementing a method for identifying sirens of a plurality of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle of the plurality of priority vehicles in an environment of the motor vehicle, the device comprising: at least one sound receiver; a computer comprising a storage configured to store a plurality of sets of frequencies each associated with a siren of a specific type of the plurality of priority vehicles, each of the plurality of sets of frequencies including at least two alternating frequencies, the computer being configured to analyze the audio recording, compare the frequencies of the audio recording with the stored sets of frequencies, and detect the presence of the at least one priority vehicle in the environment of the motor vehicle based on the comparison; and at least one visual and/or vibratory system configured to warn the driver when the presence of the at least one priority vehicle is detected in the environment of the motor vehicle.

20. The device as claimed in claim 19, further comprising at least two microphones disposed towards the right rear and the left rear of the motor vehicle, respectively, said at least one visual and/or vibratory system configured to signal an origin of the siren to the right rear or the left rear of the motor vehicle thereby signaling a location of the at least one priority vehicle with respect to the motor vehicle of the hearing-impaired driver.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other features, aims and advantages of the present invention will become apparent from reading the detailed description that follows and from examining the appended drawings given by way of non-limiting examples, and in which:

(2) FIG. 1 is a schematic representation of a flowchart of the method according to the invention for identifying sirens of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle in an environment of his motor vehicle,

(3) FIG. 2 is a schematic representation of the elements of a device for implementing the method according to the present invention, these elements being shown next to one another in positions different from those they occupy on or in the motor vehicle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(4) With particular reference to FIG. 1, the present invention relates to a method for identifying sirens of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle in an environment of his motor vehicle.

(5) The method comprises a step 1 of acquiring an audio recording of the environment. This step is referenced 1 in FIG. 1 and is carried out using at least one sound receiver referenced 1a in FIG. 2. This acquiring step 1 is followed by a filtering step 2 which is not essential in the context of the present invention and which will be described in more detail below.

(6) The next step is carried out in a computing unit 3 and consists of a step 4, 5 of analyzing the audio recording. This step 4, 5 of analyzing the audio recording is divided into a sub-step 4 of analyzing the audio recording spectrally with a view to identifying the noteworthy frequencies, and a sub-step 5 of comparing the frequencies acquired from the audio recording with frequencies previously stored as being associated with a siren of a given priority vehicle, and of doing so for each type of priority vehicle, these frequencies being referred to as fundamental frequencies.

(7) These frequencies will have been stored in the computing unit 3 prior to its installation in the motor vehicle, but may be updated by download in case of changes to siren frequencies.

(8) The following table gives, by way of nonlimiting example, a list of fundamental frequencies:

(9) TABLE-US-00001 Fundamental frequencies 420 ± 8 Hz 435 ± 8 Hz 488 ± 8 Hz 516 ± 8 Hz 580 ± 8 Hz 651 ± 8 Hz 732 ± 8 Hz

(10) The signal of a siren of a priority vehicle is characterized by the alternation of two or three fundamental frequencies. Each siren possesses a defined and standardized pattern: Ambulance 60 cycles/min: 420 Hz/516 Hz/420 Hz/silence 1.5 s Firemen 25 to 30 cycles/min: 435 Hz/488 Hz Gendarmerie 50 to 60 cycles/min: 435 Hz/732 Hz Police 50 to 60 cycles/min: 435 Hz/580 Hz

(11) The siren signal is made up of these fundamental frequencies and of their harmonics and other integer multiples of the fundamental frequency. Generally, it is possible to detect at most the 7.sup.th harmonic, and therefore to determine at least the 5.sup.th harmonic.

(12) The comparison is made, on the one hand, between the one or more frequencies of each type of siren and, on the other hand, the frequencies acquired and extracted from the audio recording with a view to identifying whether one or more frequencies acquired and extracted from the audio recording are those of a siren of a given priority vehicle.

(13) In the event of an alternation of frequencies in a siren signal of a given priority vehicle, it may also be checked whether this alternation of frequencies is present in the succession of frequencies extracted from the acquired audio signal. It is then possible to identify the exact type of priority or emergency vehicle that emitted the siren.

(14) This comparison may be based on the fundamental frequencies and at least their first five harmonics.

(15) When it is detected that frequencies of a siren of a given priority vehicle are present in the audio recording, a step 6 of warning the hearing-impaired driver that a priority vehicle is driving in the environment of his vehicle is carried out.

(16) This will allow him to give way as quickly as a driver who actually heard the siren and will decrease the number of accidents, the priority vehicle not being forced to wait for a driver to give way.

(17) To avoid false detections of siren signals or to avoid triggering unnecessary warnings, the following optional measures may be implemented.

(18) The acquired frequencies may be taken into account only if their amplitude is higher than a minimum threshold, 93 decibels for example.

(19) As mentioned above, the analyzing step 4, 5 takes into account at least one fundamental frequency of a given siren with at least its first five harmonics with a view to establishing a reliable comparison with previously stored siren fundamental frequencies and harmonics.

(20) The one or more memorized siren frequencies may not be the only parameter of comparison with the acquired audio recording. An alternation of frequencies and a number of cycles per minute of repetitions of the frequencies specific to the siren may be stored.

(21) Thus, it may not be enough for the audio recording to contain two frequencies typical of a stored siren for a warning to be sent to the driver, it then also being required that the extracted frequencies alternate in the order stored for said siren and/or according to the stored cycle.

(22) In order to avoid noises giving rise to parasitic frequencies and to keep only the useful audio signal, prior to the step 4, 5 of analyzing the audio recording, band-pass filtering 2 with a pass band comprised between 400 Hz and 7 kHz may be carried out on the audio recording. The filter 2a may be a passive RLC filter or an active filter, these filters being well known to those skilled in the art.

(23) The warning step 6 may indicate the origin of the siren with respect to the vehicle and the type of priority vehicle associated with the detected siren, i.e. whether the vehicle is coming mainly from the right rear or from the left rear with respect to the vehicle. Detection from in front of the vehicle is less essential, given that the hearing-impaired driver will be able to see the priority vehicle as it arrives.

(24) However, it may be judicious to provide for lateral detection, for example at a right-angle intersection where lateral visibility is limited and the priority vehicle only identifiable by its siren.

(25) With reference to FIGS. 1 and 2, the invention relates to a device for implementing a method such as described above for identifying sirens of priority vehicles and for warning a hearing-impaired driver of a motor vehicle of a presence of at least one priority vehicle in an environment of his vehicle, this device being located on-board the motor vehicle.

(26) The device comprises at least one sound receiver 1a, advantageously taking the form of at least one microphone, and a computing unit 3 with means for analyzing the audio recording and means for comparing the frequencies of the audio recording with frequencies previously stored in storage means of the computing unit 3 as being associated with a siren of a given priority vehicle, and for doing so for each type of priority vehicle.

(27) The device also comprises at least one visual and/or vibratory element 9, 7g, 7d for warning the driver when a presence of a priority vehicle is detected in an environment of the motor vehicle.

(28) The warning elements 9, 7g, 7d may have a number of aspects. The warning element or one of the warning elements may be able to emit a light signal in a field of view of the hearing-impaired driver.

(29) Alternatively or in addition, the warning element or one of the warning elements 9, 7g, 7d may transmit vibrations from a unit 8 of the motor vehicle, said vibrations being transmitted to the hearing-impaired driver.

(30) In FIG. 2, an indicator light 9 and vibrating means 7d and 7g are shown, d and g standing for the right and left of a motor-vehicle steering wheel 8, which is then the part of the motor vehicle made to vibrate.

(31) This is non-limiting and the light signal may be emitted by one or more indicator lights or be displayed on an instrument panel using an icon or in the form of a text message displayed on a screen of an on-board computer of the motor vehicle.

(32) Alternatively or in addition, the vibrating means may act on the seat instead of the steering wheel 8 of the hearing-impaired driver. The text message may also specify the type of priority vehicle approaching.

(33) In one preferred embodiment, the device may comprise at least two microphones 1a by way of sound receivers, arranged towards the right rear and the left rear of the motor vehicle, respectively. The microphones 1a may be positioned on the vehicle between 0.5 and 1.5 meters from the ground.

(34) In the case of a plurality of microphones 1a, it is advantageous for at least one warning element to comprise means 7d, 7g for signaling an origin of the siren to the right rear or the left rear of the motor vehicle and as a consequence a location of the priority vehicle with respect to the motor vehicle of the hearing-impaired driver.

(35) This may be done by making the unit, the steering wheel 8 for example, vibrate only on the side from which the priority vehicle is coming, by means of vibrating means on the right 7d or left 7g of the steering wheel 8. Likewise, the displayed message may comprise the direction of origin of the priority vehicle and the warning icon on the instrument panel may be doubled on the right or left or be associated with a right or left arrow.

(36) It is possible for the driver to put the device on standby, mainly to allow for a change of driver to one who is not hearing-impaired.

(37) In a broader context, the present invention may be integrated into an autonomous vehicle, with the aim of integrating into such vehicles the incorporation of external sounds and danger signals due to the approach of priority vehicles into decision making.