JP2005080227A - Method for providing sound information, and directional sound information providing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound information providing method for forming a highly directional acoustic space, moving the acoustic space in response to the position or movement of an object person, and changing information to be provided, and to provide a directional sound information providing device. <P>SOLUTION: The device includes: a position measuring part 1 for measuring the position of the object person; a sound information changeover part 3 having a plurality of patterns of sound information, fetching the output of the position measuring part 1 and selectively outputting signal wave to be the sound information in response to the position of the object person; a carrier wave generating part 2 for fetching the output of the position measuring part 1, changing the frequency of the carrier wave in response to a distance to the object person, and outputting it; a modulator 4 for modulating the carrier wave by the signal wave; an ultrasonic transducer 6 which is driven by a modulation signal outputted from the modulator, converts the modulation signal into sonic wave with a finite amplitude level, and oscillates the acoustic signal of a wide frequency band to be radiated into a medium; and a control part 8 for controlling the operations of each part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention provides a sound information providing method and directivity capable of forming a highly directional acoustic space using a broadband ultrasonic transducer and moving the acoustic space in accordance with the position and movement of a target person. The present invention relates to a type audio information providing apparatus.

  There are many scenes where you want to provide audio information only to people in a specific area (location), such as exhibition explanations at museums and art museums, and explanations of operations at ticket machines and ATMs (Automatic Teller Machines). In such a case, the conventional speaker is generally not strong in directivity, so it can be heard by people around the guidance target person, and it can be a noise for those who do not need guidance. There is.

In addition, there is a problem in that unnecessary information is provided to a person who needs another guidance, which is rather confusing.
On the other hand, a loudspeaker having a strong directivity applying the principle of self-demodulation due to air nonlinearity has been proposed (see Patent Documents 1 and 2).
When an ultrasonic carrier wave with high sound pressure is amplitude-modulated with an audible sound signal and radiated into the air, the sound speed increases at high sound pressure, and the sound speed decreases at low sound pressure due to air nonlinearity. Occur.

As a result, it is known that as the sound wave propagates through the air, distortion is accumulated in the waveform, the carrier wave component is gradually attenuated, and the audible sound component used for modulation is self-demodulated. This phenomenon is called a parametric array, and a speaker to which this principle is applied is called a parametric speaker (ultrasonic speaker) or a super directional speaker. Hereinafter, it is described as an ultrasonic speaker in this specification. Since the audible sound that is self-demodulated by being conveyed by ultrasonic waves has a sharp directivity, the ultrasonic speaker is used for local announcements, exhibition explanations, operation guidance, and the like.
JP 2002-204492 A Japanese Patent Laid-Open No. 2003-47085

  By the way, when a sound wave propagates in the air, energy is lost due to viscosity and heat conduction as a result of vibration of particles in the air accompanying the propagation of the sound wave. Since the magnitude of energy attenuation due to such air absorption is proportional to the square of the frequency of the sound wave, the higher the frequency, the shorter the sound wave reach. In other words, by changing the frequency of the carrier wave, the reach distance can be changed without changing the self-demodulated sound pressure, that is, the reproduction sound pressure.

  The conventional ultrasonic speaker uses a resonance type ultrasonic transducer using a piezoelectric element as a vibrating body. However, the resonance type transducer has a vibration frequency characteristic band as shown in FIG. Narrow (narrow band). For this reason, the ultrasonic speaker using the conventional resonant transducer is not suitable for controlling (changing) the reach of acoustic information.

  Furthermore, in order to provide information (guidance) along a person's movement and route, the conventional speaker needs to have a plurality of speakers or mechanically scan the speaker according to the movement of the guidance target. Therefore, there is a problem that the installation space is increased and the cost is increased.

  The present invention has been made in view of such circumstances, and forms an acoustic space with high directivity using an ultrasonic transducer capable of oscillating an acoustic signal in a wide frequency band. Accordingly, an object of the present invention is to provide a voice information providing method and a directional voice information providing apparatus capable of moving the acoustic space and changing the voice information to be provided.

  In order to achieve the above object, the invention described in claim 1 uses position measurement means for measuring the position of the target person and voice information output means for outputting voice information, and the target person is based on the output of the position measurement means. The spatial range in which the audio information is provided by the audio information output means and the content of the audio information to be provided are dynamically changed according to the position of the target person.

  The invention according to claim 2 is a directional information providing device that provides audio information to a target person, and includes a position measuring unit that measures the position of the target person, and a plurality of audio information patterns. Audio information switching means for selectively outputting a signal wave serving as the audio information according to the distance to the target person taking in the output of the position measuring means, and distance to the target person taking in the output of the position measuring means The carrier wave generating means for changing the frequency of the carrier wave according to the output, the modulation means for modulating the carrier wave with the signal wave, and the modulation signal driven by the modulation signal output from the modulation means It has an ultrasonic transducer that can oscillate an acoustic signal in a wide frequency band that is converted into an acoustic wave of an amplitude level and radiates into a medium, and a control means that controls the operation of each part And wherein the door.

  The invention described in claim 3 further includes a driving unit that mechanically changes an angle of a sound wave emission axis of the ultrasonic transducer according to claim 2, and the control unit includes: The drive means is controlled to change the angle of the sound wave emission axis of the ultrasonic transducer according to the position of the target person.

  The invention according to claim 4 is a directional information providing device that provides audio information to a target person, and includes a position measuring unit that measures the position of the target person, and a plurality of audio information patterns. Audio information switching means for selectively outputting a signal wave serving as the audio information according to the distance to the target person taking in the output of the position measuring means, and distance to the target person taking in the output of the position measuring means The carrier wave generating means for changing the frequency of the carrier wave according to the output, the modulation means for modulating the carrier wave with the signal wave, and the modulation signal driven by the modulation signal output from the modulation means A plurality of ultrasonic transducers capable of oscillating a wide frequency band acoustic signal that is converted into an acoustic wave of an amplitude level and radiated into a medium, and the plurality of ultrasonic transducers A plurality of phase shifters that shift the phase of the modulation signal input to each, and a radial direction angle of ultrasonic waves that are output from the plurality of ultrasonic transducers by adjusting the amount of phase shift of the plurality of phase shifters And control means for controlling.

  According to a fifth aspect of the present invention, in the directional audio information providing apparatus according to any one of the second to fourth aspects, the position measuring means is an ultrasonic wave capable of oscillating an acoustic signal in a wide frequency band. A transducer is included, and the ultrasonic transducer is also used as an ultrasonic transducer for outputting voice information.

  Further, the invention according to claim 6 is the directional sound information providing apparatus according to claim 5, wherein the control means is a position measurement mode for measuring the position of the target person, and sound information for outputting sound information. It is characterized by switching the output mode to operate.

  The invention according to claim 7 is the directional audio information providing apparatus according to any one of claims 2 to 6, wherein the control means causes the position measuring means to scan a wide spatial region with ultrasonic waves, The voice information providing operation is started using a state in which the presence of the target person is detected as a trigger.

According to the present invention, since voice information can be provided by limiting the position, information can be provided only to a person who needs guidance, and a person who does not need guidance is confused with unnecessary information. I won't let you down.
In addition, since the information can be provided while changing the contents of the voice information in accordance with the movement of the person, it is possible to realize a polite and reliable information provision (guidance). This is particularly effective for guiding visually handicapped persons. For example, if an ultrasonic transducer is used, a person (moving object) can be detected even when the field of view is lost due to smoke or the like, so that it is possible to perform reliable evacuation guidance in an emergency.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the configuration of a directional audio information providing apparatus according to the first embodiment of the present invention. The audio information providing apparatus uses a position measuring unit that measures the position of the target person and a voice information output unit that outputs audio information, and tracks the target person based on the output of the position measuring unit. An apparatus for carrying out a voice information providing method characterized by dynamically changing a spatial range in which voice information is provided by the voice information output means according to a position and contents of the voice information to be provided.

  In FIG. 1, a directional audio information providing apparatus according to a first embodiment of the present invention includes a position measuring unit 1 that measures the position of a target person P that provides audio information, and a carrier wave generating unit 2 that generates a carrier wave. A voice information switching unit 3 that outputs voice information (signal waves) to be provided, a modulator 4, a power amplifier 5, an ultrasonic transducer 6, a transducer driving unit 7, and a control unit 8 that controls each unit; have.

  An example of a specific configuration of the position measurement unit 1 suitable for the present embodiment is shown in FIG. The position measuring unit 1 includes a first ultrasonic transducer 10 (TS1), a second ultrasonic transducer 11 (TS2), a signal generating unit 12, an ultrasonic receiving unit 13 (RS), and a bandpass filter unit. 14-1 (BPF-A) to 14-n (BPF-S), counter units 15-1 (A) to 15-n (S), and an integrated measuring unit 16 are included.

  This position measurement unit 1 uses the fact that the ultrasonic wave output from the ultrasonic transducer has different ultrasonic directivity characteristics (directivity angle) depending on the frequency, and performs spatial encoding (space) based on the oscillation frequency of the ultrasonic transducer. Wide frequency band oscillation by associating the ultrasonic oscillation frequency output from the ultrasonic transducer with the spatial region that is the ultrasonic radiation region. By using a small number of ultrasonic transducers of the type, position measurement with high spatial resolution in the lateral direction (direction perpendicular to the distance direction) is performed.

  The first ultrasonic transducer 10 (TS1) has a function of oscillating ultrasonic waves over a wide frequency band for radiating ultrasonic waves to a target. The first ultrasonic transducer 10 generates and outputs burst waves having a plurality of frequencies. For this purpose, the first ultrasonic transducer 10 is a wide frequency band oscillation type ultrasonic transducer. As the first ultrasonic transducer 10, for example, an electrostatic ultrasonic transducer is used.

The second ultrasonic transducer 11 (TS2) generates and outputs a single frequency ultrasonic wave. Therefore, unlike the first ultrasonic transducer 10, the second ultrasonic transducer 11 (TS2) does not have to be a wide-frequency-band oscillation type ultrasonic transducer, but a piezoelectric-type narrow-frequency-band oscillation type supersonic transducer. A sonic transducer may be used.
The second ultrasonic transducer 11 (TS2) specifies a spatial region that is an ultrasonic radiation region centered on the ultrasonic radiation axis that is the normal direction of the sound radiation surface of the first ultrasonic transducer 10. It has a function of emitting ultrasonic waves having a single frequency to the region.

The signal generator 12 generates burst signals for driving the first ultrasonic transducer 10 (TS1) and the second ultrasonic transducer 11 (TS2), respectively, and the first ultrasonic transducer 10 (TS1). , And supplied to the second ultrasonic transducer 11 (TS2).
The signal generator 12 generates and supplies a burst signal whose frequency changes stepwise in time series to the first ultrasonic transducer 10 (TS1). That is, the signal generation unit 12 generates a burst wave that lowers the oscillation frequency of the first ultrasonic transducer 10 at first, for example, and increases in a time-series and stepwise manner. 10 is supplied. By driving in this way, the burst wave of ultrasonic waves radiated into the space has a large directivity angle at first, and the directivity angle becomes smaller (sharp) step by step.

In addition, the signal generator 12 generates and supplies a burst signal having a single frequency to the second ultrasonic transducer 11 (TS2).
Further, the signal generator 12 synchronizes with each burst signal output, and trigger signals (trg-A, trg-B,..., Start counting up of the counters in the counter units 15-1 to 15-n. trg-S) is output. In addition, the signal generation unit 12 sends measurement time information, which is time information indicating the output timing of the burst signal output to the first and second ultrasonic transducers 10 and 11 and the output period of the burst signal, to the integrated measurement unit 16. Output. This measurement time information is time information necessary for signal processing in the integrated measurement unit 16.
As will be described later, the integrated measurement unit 16 has a table in which the oscillation frequencies of the first and second ultrasonic transducers 10 and 11 and the ultrasonic radiation space area corresponding to the oscillation frequencies are associated in advance. ing. For this reason, first. By driving the second ultrasonic transducers 10 and 11 as described above, the ultrasonic radiation space is virtually divided, and an oscillation frequency is associated with each divided spatial region (performs spatial coding). ) Becomes possible.

  The ultrasonic receiving unit 13 (RS) has a function of receiving a reflected wave of an ultrasonic wave output from the ultrasonic transducers 10 and 11 and reflected by a target (target person). In the present embodiment, the ultrasonic receiver 13 (RS) uses the electrostatic ultrasonic transducer used in the first ultrasonic transducer 10 and changes voltage generated between both electrodes in a state where a DC bias is applied. By detecting, it is possible to configure the ultrasonic receiver 13 (RS) that converts an ultrasonic signal (reflected wave) in a wide frequency band into an electric signal.

  Each of the bandpass filter units 14-1 (BPF-A) to 14-n (BPF-S) has a bandpass filter, and the frequency of the reflected wave of the ultrasonic wave received by the ultrasonic wave receiving unit 13 (RS). It has a function to separate each. The passbands of the bandpass filters in the bandpass filter units 14-1 (BPF-A) to 14-n (BPF-S) are different from each other, and the filter frequency characteristics are set so that the passbands do not overlap each other. (The pass band of each filter has a filter characteristic such that each burst wave frequency generated by the signal generator 12 is the center frequency of the pass band width and other burst wave frequency components are cut off.)

The counter units 15-1 (A) to 15-n (S) are reflected waves for each frequency component separated by the bandpass filter units 14-1 (BPF-A) to 14-n (BPF-S). It has the function to measure the time from the transmission time of the ultrasonic wave to become the reception time.
Each counter in the counter units 15-1 (A) to 15-n (S) is synchronized with each trigger signal (trg-A, trg-B,..., Trg-S) output from the signal generating unit 12. The count value is reset to start counting up, and the reflected wave detection signals (detA, detB,...) Output from the bandpass filter units 14-1 (BPF-A) to 14-n (BPF-S). , DetS) and the count-up is completed.

Based on the outputs cnt-A to cnt-S of the counter units 15-1 (A) to 15-n (S), the integrated measuring unit 16 transmits a burst wave to each frequency component and then reflects the reflected wave. The time until receiving each is measured, and these measurement results are integrated to calculate the space area where the target person exists and the distance to the target, and determine the position of the target person.
The integrated measurement unit 16 is centered on the oscillation frequency of the first and second ultrasonic transducers 10 and 11 and the ultrasonic radiation axis that is the normal direction of the sound wave radiation surface of the ultrasonic transducer at the oscillation frequency. Storage means for storing a table in which a spatial region to be a radiation region of ultrasonic waves is associated in advance, referring to the table from the frequency of the reflected wave of the ultrasonic wave received by the ultrasonic wave reception unit 13 A spatial region where a target person as a target is present is identified, and a distance from the time point of transmission of ultrasonic waves to the time of reception is calculated.

By the way, in the position measurement unit 1 in the present embodiment, in order to perform measurement with a wide lateral measurement range and high spatial resolution, a wide frequency band oscillation type ultrasonic transducer is used for each transmission / reception unit, and oscillation (transmission) is performed. Although the configuration in which the frequency is changed in stages and the measurement is performed in time series is shown, the present invention is not limited to this. For example, in applications that can be handled only by distance measurement, such as for providing information in a narrow passage, a piezoelectric (narrowband) ultrasonic transducer that is commonly used can be used for each of the transmitting and receiving units. Of course it is possible.
In the present embodiment, an ultrasonic transducer is used as a distance sensor that constitutes the position measurement unit 1, but the position measurement unit 1 is configured using a sensor such as an infrared sensor or an image sensor without being limited thereto. You may do it.
Next, the configuration of the carrier wave generator 2 is shown in FIG. In the figure, the carrier wave generation unit 2 includes a frequency control unit 20, a frequency information storage unit 21, and a carrier wave oscillation source 22.
The frequency information storage unit 21 stores a table indicating the relationship between the distance to the target person as the target and the oscillation frequency of the carrier wave oscillation source.

  The relationship between the distance to the target person and the oscillation frequency of the carrier wave oscillation source is set such that, for example, the frequency of the carrier wave is increased as the target person approaches the audio information providing apparatus, that is, as the distance to the target person decreases. By setting to, it is possible to form an acoustic space in which the audio information to be provided reaches far when the distance to the target person is long, and only reaches a short distance when the distance is close.

The frequency control unit 20 obtains a frequency corresponding to the distance to the target person from the distance data to the target person input from the position measurement unit 1 with reference to a table stored in the frequency information storage unit 21, The carrier wave oscillation source 22 is controlled so as to generate a carrier wave. As a result, the carrier wave generator 2 generates a carrier wave having a frequency corresponding to the distance to the target person and outputs the carrier wave to the modulator 4.
The carrier wave generation unit 2 is configured to have a plurality of oscillation units that oscillate carrier waves of different fixed frequencies, and to switch so that a carrier wave of a predetermined frequency is selected according to distance information. May be.

Next, the configuration of the voice information switching unit 3 is shown in FIG. In the figure, the audio information switching unit 3 includes an audio information output unit 30, an audio information storage unit 31, and a signal wave generation unit 32.
The voice information storage unit 31 stores a table indicating the relationship between the distance to the target person who is the target and the voice information to be provided. For example, a plurality of patterns are prepared in advance for voice information, for example,
Distance to the target person Voice information pattern 10-5m A (Please go straight to XX)
5-2m B (Turn right to XX soon)
2 ~ 0m C (Please turn right here to XX)
Thus, the detected distance range and each pattern of the voice information are associated with each other and stored in the voice information storage unit as a table. Thereby, appropriate audio information (guidance) can be provided according to the position and movement of the target person.

The audio information output unit 30 obtains audio information corresponding to the distance from the distance data to the target person input from the position measurement unit 1 with reference to a table stored in the audio information storage unit 31, and the audio information Is output to the signal wave generator 32.
The signal wave generation unit 32 converts the audio information input from the audio information output unit 30 into a format that can be modulated by the modulator 4, for example, an analog signal (signal wave), and outputs the analog signal (signal wave) to the modulator 4.
As described above, the audio information switching unit 3 switches the audio information to be reproduced according to the distance data to the target person output from the position measurement unit 1.

  The modulator 4 amplitude-modulates the carrier wave output from the carrier wave generation unit 2 with the signal wave (audio information) output from the audio information switching unit 3, and transmits the modulation signal to the ultrasonic transducer via the power amplifier 5. 6 is output.

The ultrasonic transducer 6 is driven by the modulation signal output from the modulator 4 and converts the modulation signal into a sound wave of a finite amplitude level and radiates it into the medium (in the air). When an ultrasonic carrier wave (carrier wave) with a high sound pressure is radiated into the air after amplitude modulation with an audible sound signal as described above, the sound speed increases at high sound pressures and the sound speeds at low sound speeds due to air nonlinearity. Becomes low, and the waveform is distorted. As a result, as the sound wave propagates through the air, distortion is accumulated in the waveform, the carrier wave component is gradually attenuated, and the audible sound component used for modulation is self-demodulated (parametric array effect). The audible sound that is self-demodulated by being conveyed by ultrasonic waves has a sharp directivity, and can constitute an ultrasonic speaker.
The ultrasonic transducer 6 in the embodiment of the present invention can oscillate an acoustic signal in a wide frequency band. A specific configuration of the ultrasonic transducer 6 is shown in FIG. In the figure, the electrostatic ultrasonic transducer 6 uses a dielectric 41 (insulator) such as PET (polyethylene terephthalate resin) having a thickness of about 3 to 10 μm as a vibrating body. For the dielectric 41, an upper electrode 42 formed as a metal foil such as aluminum is integrally formed on the upper surface by a process such as vapor deposition, and a lower electrode 43 formed of brass is formed on the lower surface of the dielectric 41. It is provided so that it may contact a part. The lower electrode 43 is connected to a lead 52 and is fixed to a base plate 45 made of bakelite or the like.

  The upper electrode 42 is connected to a lead 53, and the lead 53 is connected to a DC bias power supply 50. A DC bias voltage for attracting the upper electrode of about 50 to 150 V is always applied to the upper electrode 42 by the DC bias power source 50, and the upper electrode 42 is attracted to the lower electrode 43 side. Reference numeral 51 denotes an AC signal source (in this embodiment, the output of the power amplifier 5). The dielectric 41, the upper electrode 42, and the base plate 45 are caulked by the case 40 together with the metal rings 46, 47, and 48 and the mesh 49.

  On the surface of the lower electrode 43 on the dielectric 41 side, a plurality of minute grooves of about several tens to several hundreds μm having a non-uniform shape are formed. Since this minute groove becomes a gap between the lower electrode 43 and the dielectric 41, the electrostatic capacity distribution between the upper electrode 42 and the lower electrode 43 changes minutely. These random minute grooves are formed by roughing the surface of the lower electrode 43 manually. In the electrostatic ultrasonic transducer, the frequency characteristics of the ultrasonic transducer 6 have a wide band as shown by a curve Q1 in FIG. 9 by forming innumerable capacitors having different gap sizes and depths. ing.

In the ultrasonic transducer 6 having the above configuration, an AC signal voltage (output of the power amplifier 5) is applied between the upper electrode 41 and the lower electrode 43 in a state where a DC bias voltage is applied to the upper electrode. ing. Incidentally, as shown by the curve Q2 in FIG. 9, the frequency characteristic of the resonance type ultrasonic transducer has a center frequency (resonance frequency of the piezoelectric ceramic) of, for example, 40 kHz, and ± 5 kHz with respect to the center frequency that is the maximum sound pressure. -30 dB with respect to the maximum sound pressure at a frequency of. On the other hand, the frequency characteristic of the broadband oscillation type ultrasonic transducer having the above configuration is flat from 40 kHz to around 100 kHz, and is about ± 6 dB compared to the maximum sound pressure at 100 kHz.
As described above, when the ultrasonic wave propagates in the medium (in the air), the reaching distance becomes shorter as the frequency of the sound wave becomes higher. Since the ultrasonic transducer 6 has a wideband frequency characteristic, the self-demodulated sound pressure level, that is, the reproduction sound pressure is changed by driving the ultrasonic transducer 6 while changing the frequency of the carrier wave carrying audio information. The reach of the reproduced sound can be controlled without any problem.
Note that the ultrasonic transducer 10 constituting the position measurement unit 1 also has the same configuration and characteristics as the ultrasonic transducer 6 described above.

  The transducer drive unit 7 has a function of mechanically changing the angle of the sound wave emission axis (normal direction of the sound wave emission surface) of the ultrasonic transducer 6. Although not shown in the figure, for example, an actuator that drives the ultrasonic transducer 6 and a drive unit that electrically drives the actuator, and based on a control signal from the control unit 8, Control to change the angle of the axis.

  The control unit 8 controls operations of the position measurement unit 1, the carrier wave generation unit 2, the audio information switching unit 3, and the transducer driving unit 7. Specifically, according to the position of the target person P measured by the position measuring unit 1, the transducer driving unit 7 is controlled so that the sound wave emission axis of the ultrasonic transducer 6 faces the target person P. Furthermore, the operation of the audio information providing apparatus can be controlled to be switched between a position measurement mode for measuring the position of the target person P and an audio information output mode for outputting audio information to a space area where the target person exists. It is like that.

In the above configuration, the control unit 8 periodically switches the operation mode to the position measurement mode at regular intervals, for example, and operates the position measurement unit 1 to determine the position of the target person P who is the provision target of audio information. measure.
The control unit 8 switches to the audio information output mode every time the operation of the position measurement mode is completed, and operates the carrier wave generation unit 2, the audio information switching unit 3, and the transducer driving unit 7. As a result, the voice information previously associated with the distance to the target person based on the detected distance data between the target person P and the voice information providing apparatus is sent from the voice information switching unit 3 to the modulator 4 as a signal wave. In addition to being output, the carrier wave generation unit 2 outputs a carrier wave whose frequency is changed so that the voice information reaches the target person P to the modulator 4.
In the present embodiment, by adjusting both the arrangement and the oscillation frequency so that the ultrasonic wave output from the position measuring unit 1 and the ultrasonic wave output from the ultrasonic transducer 6 do not strongly interfere with each other, It is also possible to overlap the position measurement mode and the sound information output mode, that is, to output sound information while performing position measurement.

In the modulator 4, the carrier wave input from the carrier wave generator 2 is modulated by the signal wave input from the audio information switching unit 3, and the modulated signal is output to the power amplifier 5. The power amplifier 5 amplifies the modulation signal to a predetermined level and outputs it to the ultrasonic transducer 6.
The ultrasonic transducer 6 is driven by the modulation signal, converts the modulation signal into a sound wave of a finite amplitude level, and radiates it into the medium (air).
The direction of the ultrasonic transducer 6 is controlled by the transducer driving unit 7 based on the position data from the position measuring unit 1 so that the sound wave emission axis of the ultrasonic transducer 6 faces the target person P under the control of the control unit 8. The

  As described above, according to the directional audio information providing apparatus according to the present embodiment, as shown as an image diagram in FIG. 10, a space for providing audio information corresponding to the position (distance) of the target person P to the target person P. The range (audio information reproduction range) and the content of the audio information to be provided can be dynamically changed. In FIG. 10, the distance l between the target person P and the directional audio information providing apparatus has a relationship of l1 <l2 <l3.

  Next, FIG. 5 shows the configuration of a directional audio information providing apparatus according to the second embodiment of the present invention. The directional audio information providing apparatus according to the present embodiment differs from the audio information providing apparatus according to the first embodiment in configuration in that a plurality of ultrasonic transducers 6-1 to 6-1 are used instead of the single ultrasonic transducer 6. 6-6, and a phase shift circuit 9 for controlling the radiation direction of the synthesized wave of the ultrasonic waves radiated from the plurality of ultrasonic transducers 6-1 to 6-6. Since the configuration is the same as that of the first embodiment, a duplicate description is omitted. In this embodiment, the number of ultrasonic transducers is six, but it is not necessary to limit to this.

The configuration of the phase shift circuit 9 is shown in FIG. As shown in the figure, the phase shift circuit 9 includes phase shift shift units 90 to 95 provided in each of the plurality of ultrasonic transducers 6-1 to 6-6. The amount of phase shift of each of the phase shift units 90 to 95 is set by a control signal from the control unit 8.
In FIG. 5, the control unit 8 to which the distance data to the target person P obtained by the operation in the position measurement mode is input corresponds to the phase shift units 90 to 90 in the phase shift circuit 9 according to the position of the target person P. Set a phase shift amount of 95.

  In FIG. 11, in order to output the ultrasonic waves modulated by the signal waves radiated from the ultrasonic transducers 6-1 to 6-6 at the same direction angle θ, the drive signal supplied to the ultrasonic transducer 6-1. If the phase shift amount of the phase shift unit 90 that shifts the phase of the (modulation signal) is used as a reference, the phase shift amounts of the other phase shift units 91 to 95 are set to a predetermined phase shift amount with respect to the phase shift amount of the adjacent phase shift unit. Set to increase or decrease sequentially by the phase amount. Thereby, the synthetic wavefront of the sound wave radiated from each of the ultrasonic transducers 6-1 to 6-6 is radiated at the direction angle θ, and the radiation direction angle of the sound wave to be output according to the position detected by the position measuring unit 1 is set. Can be controlled.

  Next, FIG. 6 shows the configuration of a directional audio information providing apparatus according to the third embodiment of the present invention. The directional audio information providing apparatus according to the present embodiment differs in configuration from the directional audio information providing apparatus according to the first embodiment in that the position measuring unit 1 is provided without providing the ultrasonic transducer 6 for outputting audio information. Of these, the first ultrasonic transducer 10 (TS1) is used for both position measurement and voice information output. For this purpose, a mode switch 100 for switching the input system of the first ultrasonic transducer 10 (TS1) is added and input to the first ultrasonic transducer 10 (TS1) in the position measurement mode and the audio information output mode. The signal is switched.

FIG. 7 shows the configuration of the signal measuring unit 1, and the difference from FIG. 2 is that the first ultrasonic transducer 10 is normally (in the position measurement mode) of the mode switch 100 under the control of the control unit 8. It is switched to the contact a side, and is switched to the contact b side by the control signal CS output from the control unit 8 in the voice information output mode. Since the other configuration is the same as that of the first embodiment, the redundant configuration and the description thereof are omitted.
In the above configuration, in the position measurement mode, the first ultrasonic transducer 10 is driven by the burst signal output from the signal generator 12, and the position of the target person P is measured by the above-described operation.

  When the operation of the audio information providing device is switched to the audio information output mode, the control signal CS is output from the control unit 8 to the mode switch 100, and the mode switch 100 is switched to the contact b side to load the audio information. The modulated signal is amplified by the power amplifier 5, and the output is output to the first ultrasonic transducer 10. As a result, sound information corresponding to the position of the target person P is output from the first ultrasonic transducer 10.

  According to the third embodiment, since the wide frequency band oscillation type ultrasonic transducer can be used for both position measurement and voice information output, the apparatus can be simplified and the cost can be reduced.

  The present invention can be applied to amusement equipment, sound production in facilities, and the like.

The block diagram which shows the structure of the directional audio | voice information provision apparatus which concerns on 1st Embodiment of this invention. The block diagram which shows the structure of the position measurement part in the directional audio | voice information provision apparatus which concerns on 1st Embodiment of this invention shown in FIG. The block diagram which shows the structure of the carrier wave production | generation part in the directional audio | voice information provision apparatus which concerns on 1st Embodiment of this invention shown in FIG. The block diagram which shows the structure of the audio | voice information switching part in the directional audio | voice information provision apparatus which concerns on 1st Embodiment of this invention shown in FIG. The block diagram which shows the structure of the directional audio | voice information provision apparatus which concerns on 2nd Embodiment of this invention. The block diagram which shows the structure of the directional audio | voice information provision apparatus which concerns on 3rd Embodiment of this invention. The block diagram which shows the structure of the position measurement part shown in FIG. The figure which shows the specific structure of the ultrasonic transducer in the directional audio | voice information provision apparatus which concerns on embodiment of this invention shown in FIG. The characteristic view which shows the frequency characteristic of the ultrasonic transducer shown in FIG. The image figure which shows the state which provides audio | voice information with respect to a target person by the audio | voice information provision apparatus which concerns on embodiment of this invention. Explanatory drawing which shows the structure of the phase shift circuit shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Position measuring part, 2 ... Carrier wave production | generation part, 3 ... Audio | voice information switching part, 4 ... Modulator, 5 ... Power amplifier, 6, 10, 11 ... Ultrasonic transducer, 7 ... Transducer drive part, 8 ... Control part , 13 ... ultrasonic wave receivers, 14-1 to 14-n ... band pass filter units, 15-1 to 15-n ... counter units, 16 ... integrated measurement units

Claims (7)

Using the position measurement means for measuring the position of the target person and the sound information output means for outputting sound information, the sound information is tracked according to the position of the target person while tracking the target person based on the output of the position measurement means. A voice information providing method characterized by dynamically changing a spatial range in which voice information is provided by output means and contents of the voice information to be provided. A directional information providing device that provides audio information to a target person,
Position measuring means for measuring the position of the target person;
Voice information switching means that has a plurality of patterns of voice information, takes in the output of the position measurement means, and selectively outputs a signal wave as the voice information according to the distance to the target person;
A carrier wave generating means for taking in the output of the position measuring means and changing the frequency of the carrier wave according to the distance to the target person and outputting the carrier wave;
Modulation means for modulating the carrier wave with the signal wave;
An ultrasonic transducer that is driven by a modulation signal output from the modulation means and can oscillate an acoustic signal in a wide frequency band that is radiated into a medium by converting the modulation signal into a sound wave of a finite amplitude level;
Control means for controlling the operation of each part;
A directional audio information providing apparatus characterized by comprising: Drive means for mechanically changing the angle of the sound radiation axis of the ultrasonic transducer;
3. The directional audio information provision according to claim 2, wherein the control unit controls the driving unit to change an angle of a sound wave emission axis of the ultrasonic transducer according to a position of the target person. apparatus. A directional information providing device that provides audio information to a target person,
Position measuring means for measuring the position of the target person;
Voice information switching means that has a plurality of patterns of voice information, takes in the output of the position measurement means, and selectively outputs a signal wave as the voice information according to the distance to the target person;
A carrier wave generating means for taking in the output of the position measuring means and changing the frequency of the carrier wave according to the distance to the target person and outputting the carrier wave;
Modulation means for modulating the carrier wave with the signal wave;
A plurality of ultrasonic transducers driven by a modulation signal output from the modulation means and capable of oscillating a wide frequency band acoustic signal to be radiated into a medium by converting the modulation signal into a sound wave of a finite amplitude level;
A plurality of phase shifters for shifting the phase of the modulation signal input to each of the plurality of ultrasonic transducers;
Control means for adjusting the amount of phase shift of the plurality of phase shifters to control the radiation direction angle of the ultrasonic waves output from the plurality of ultrasonic transducers;
A directional audio information providing apparatus characterized by comprising: The position measuring means includes an ultrasonic transducer capable of oscillating an acoustic signal in a wide frequency band, and the ultrasonic transducer is also used as an ultrasonic transducer for outputting audio information. Item 5. The directional audio information providing apparatus according to any one of Items 2 to 4. 6. The directional audio information providing apparatus according to claim 5, wherein the control means operates by switching between a position measurement mode for measuring the position of the target person and an audio information output mode for outputting audio information. . 7. The control unit according to claim 2, wherein the position measuring unit scans a wide space area with ultrasonic waves and starts a voice information providing operation using a state in which the presence of the target person is detected as a trigger. The directional audio information providing apparatus according to any one of the above.

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