JP2020134383A - Distance measuring system - Google Patents

Abstract

To provide a system that measures the distance between a master unit which is a measuring object and a slave unit which is a measured object at an arbitrary timing.SOLUTION: A distance measuring system includes: a master unit 101 that transmits a sound wave 115 and transmits time when the sound wave 115 was transmitted by a radio wave 117; and a slave unit 103 that receives the sound wave 115 and the radio wave 117, and measures a distance to and from the master unit with the time when the sound wave 115 was transmitted and time when the sound wave 115 was received. In the master unit 101 and the slave unit 103, their internal clocks are synchronized with the standard time.SELECTED DRAWING: Figure 1

Description

The present invention relates to a distance measuring system that measures a distance using sound waves.

In a distance measurement system, a transmitter transmits sound waves to hit an object, a receiver receives sound waves bounced off the object, and the time from transmission to reception is measured. By multiplying the measured time and the speed of sound, the round-trip distance to the object can be found.

The time when the sound wave is oscillated and the time when the sound wave is received are required to be accurate. Times are required to be accurate, at least in milliseconds. GPS is a technology currently in use that makes it relatively easy to obtain accurate time. Therefore, Patent Document 1 discloses that a transmitter using GPS transmits an ultrasonic signal at an accurate time, and a receiver using GPS receives ultrasonic waves at an accurate time.

JP-A-63-259484

However, in Patent Document 1, ultrasonic pulses are transmitted at a predetermined time. Therefore, the distance could not be measured at any timing. Therefore, one object of the present invention is to provide a system for measuring the distance between a master unit which is a measurement object and a slave unit which is a measurement object at an arbitrary timing in a distance measurement system synchronized with standard time by GPS or the like. And.

The distance measurement system of the present invention
A master unit that transmits sound waves and transmits the time when the sound waves were transmitted by radio waves,
A distance measuring system including a slave unit that receives the sound wave and the radio wave and measures the distance from the master unit from the time when the sound wave is transmitted and the time when the sound wave is received.
The master unit and the slave unit are characterized in that the internal clock is synchronized with the standard time.

By synchronizing with standard time, there is no need for a large time adjustment between the time when sound waves are transmitted and the time when sound waves are received. Further, by transmitting the time when the sound wave is transmitted and the waveform of the sound wave by radio waves, the distance between the master unit which is the measurement object and the slave unit which is the object to be measured can be measured at an arbitrary timing.

The present invention can provide a system for measuring the distance between a master unit, which is a measuring object, and a slave unit, which is a measured object, at an arbitrary timing in a distance measuring system synchronized with standard time by GPS or the like.

It is a schematic block diagram of the distance measurement system which concerns on Embodiment 1 of this invention. It is a flowchart of one Embodiment of the distance measurement system of this invention. It is a block diagram of a part of the distance measurement system which concerns on Embodiment 2 of this invention. It is a block diagram of a part of the distance measurement system which concerns on Embodiment 3 of this invention. It is a block diagram of a part of the distance measurement system which concerns on Embodiment 4 of this invention. It is a block diagram of a part of the distance measurement system which concerns on Embodiment 5 of this invention.

Hereinafter, various embodiments for carrying out the present invention will be described with reference to the drawings. In consideration of the explanation of the main points or the ease of understanding, the reference numerals are changed for convenience in different drawings. Although the embodiments are shown separately for convenience in consideration of the explanation of the main points or the ease of understanding, partial replacement or combination of the configurations shown in the different embodiments is possible. In the second and subsequent embodiments, the embodiments are shown separately for the sake of convenience in consideration of the ease of explanation or understanding of the main points from the first embodiment, but partial replacement or combination of the configurations shown in the different embodiments. Is possible. Further, in the second and subsequent embodiments, the description of the matters common to the first embodiment will be omitted, and only the differences will be described. In particular, the same action and effect due to the same configuration will not be mentioned sequentially for each embodiment.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a distance measurement system according to a first embodiment of the present invention. The first embodiment will be described with reference to FIG.

As shown in FIG. 1, the present embodiment includes a master unit 101 as a measurement object and a slave unit 103 as a measurement object. If GPS is used, the satellite 105 will also be incorporated into this distance measurement system.

(Sonic transmitter)
The master unit 101 includes a sound wave transmitter 107 that transmits sound waves 115. The sound wave transmitter 107 is preferably a combination of a high resolution amplifier and a speaker. The high resolution amplifier is an ultrasonic transmission / reception means capable of reproducing sound waves having a frequency of up to 96 kHz. Further, the sound wave transmitter 107 may be an audible sound amplifier and a speaker capable of reproducing sound waves having a frequency of up to 20 kHz.

The sound wave 115 may be an audible sound wave or an ultrasonic wave. The sound wave 115 is preferable when the frequency is 16 kHz or higher because it is too high to be heard by almost all people. In particular, when the frequency is about 16 kHz to 20 kHz, it is inaudible to the human ear and has a longer wavelength than ultrasonic waves, so that it can wrap around obstacles, which is more preferable.

(Radio transmitter)
The master unit 101 includes a radio wave transmitter 109 that transmits radio waves 117. The radio wave transmitter 109 can transmit digital data by digital radio such as Bluetooth (registered trademark) and Wifi. Further, it may have a function of not only transmitting radio waves but also receiving digital data from the slave unit 103.

The radio wave 117 transmits the data of the time when the sound wave 115 was transmitted and the frequency and waveform of one or more of the sound waves 115. The radio wave 117 can be transmitted simultaneously with, after, or earlier than the sound wave 115.

(Sonic receiver)
The slave unit 103 includes a sound wave receiver 111 that receives the sound wave 115. As the sound wave receiver 111, it is preferable to use an omnidirectional high-resolution microphone capable of responding up to a frequency of 96 kHz. The sound wave receiver 111 may be a separate member from the slave unit 103. Further, it may be a built-in microphone of a mobile phone device capable of responding to a frequency of up to 20 kHz. It is preferable that the sound wave receiver 111 matches the performance of transmitting and receiving sound waves of the slave unit 103 and the master unit 101.

(Radio receiver)
The slave unit 103 includes a radio wave receiver 113 that receives the radio wave 117. By matching the standard with the radio wave transmitter 109, it is possible to receive the digital data of the radio wave 117. The slave unit 103 may have a function of transmitting radio waves. As the slave unit 103, it is preferable to use a mobile phone device such as a smartphone, which is a device capable of receiving sound waves and radio waves.

(Standard time adjustment)
Here, the internal clocks (not shown) of the master unit 101 and the slave unit 103 are synchronized with the standard time by the GPS signal 119 oscillated from the satellite 105. The time of the master unit 101 and the slave unit 103 needs to be adjusted with an accuracy of 100 μs. GPS (Global Positioning System) uses an atomic clock and meets this condition.

If the master unit and the slave unit are connected to a mobile phone network or the Internet, NITZ (Network Identity and Time Zone) or NTP (Network Time Protocol) may be used instead of GPS as a method of synchronizing at standard time. .. Both are currently relatively easy-to-use means of adjusting to standard time.

(Distance measurement principle)
The slave unit 103 records the time when the sound wave 115 is received. Further, the slave unit 103 obtains the time when the radio wave 117 is received and the sound wave 115 is transmitted. The slave unit 103 subtracts the time when the sound wave 115 is transmitted from the time when the sound wave 115 is received, and measures the time t when the sound wave 115 arrives from the master unit 101 to the slave unit 103. Since the speed v of the sound is known to change depending on the temperature, the distance d between the master unit 101 and the slave unit 103 is given by the following equation.

For example, if the room temperature is 20 ° C, the speed of sound is 343.5950188 m / S.
Assuming that the transmission time is 9:34:10 am 312 ms 120 microseconds on December 27, 2018, and the reception time is 9:34:10 am 313 ms 520 microseconds on December 27, 2018.
343.5950188 × (313.52-31.12.2) × 0.001 = 0.481m
The distance is determined to be 0.481 m.

The above calculation may be performed by the slave unit 103, by the master unit 101 that has received data from the slave unit 103, or by the computer to which the slave unit 103 or the master unit 101 is connected. Further, the speed of sound may be corrected by temperature.

When the GPS error is 10 μs, the distance error is only about 3.4 mm. Since the error is about 2 m when positioning by GPS, the accuracy of measuring the distance can be significantly improved by using the distance measurement system of the present invention. In addition, it can be used in parallel with a distance measuring system using GPS or Bluetooth (registered trademark) built in a smartphone or the like to further improve the accuracy of measuring a distance.

In addition, the reception intensity of sound waves and radio may be used in combination to improve the accuracy of distance measurement. The phase information of the sound wave may be used to improve the accuracy of distance measurement.

The present invention can provide a system for measuring the distance between a master unit, which is a measuring object, and a slave unit, which is a measured object, at an arbitrary timing in a distance measuring system synchronized with standard time by GPS or the like.

Further, the present invention can provide a distance measuring system that technically relatively easily measures a distance or a position by using existing techniques such as a mobile phone device, GPS, NITZ, NTP, and a high resolution sound source.

(Flowchart of distance measurement system)
FIG. 2 is a flowchart of the distance measurement system according to the embodiment of the present invention. The flow of the distance measurement system of the present invention will be described with reference to FIG.

The flow is started, and the slave unit starts constantly receiving sound waves. The slave unit stores data on the time when the sound wave is received, the frequency of the sound wave, and the waveform of the sound wave (201). The slave unit holds data on the frequency of the sound wave, the waveform of the sound wave, and the time when the sound wave is received during a predetermined time (202). On the other hand, the master unit transmits sound waves, and at the same time, transmits the time at which the sound waves are transmitted and data of a single frequency or a plurality of frequencies and waveforms of the sound waves by radio waves.

When the slave unit receives radio waves from the master unit (203), the frequency and waveform data of the received sound waves are collated with the frequency and waveform data of the sound waves transmitted by the master unit by radio waves, and when they match more than a certain level. , The distance shown in the first embodiment is measured (204). Matching above a certain level means roughly matching or perfect matching.

For example, the master unit transmits a 40 kHz sound wave for 10 ms. The slave unit searches for a 40 kHz sound wave transmitted by radio waves over 100 ms. When a sound wave of 40 kHz is found, the rising time of the sound wave is defined as the time when the sound wave is received.

When the radio waves reach the handset, the sound waves may not have arrived yet. In that case, the frequency of the sound wave and the waveform data are collated after waiting until the time when the sound wave arrives. When measuring a distance of about 34 m, the sound wave reaches about 100 ms, so that the sound wave frequency and waveform data can be retained while sufficiently storing the sound wave frequency and waveform data.

After measuring the distance, the time when the sound wave was received and the frequency and waveform data of the sound wave are discarded. Although the process of measuring the distance is completed, the slave unit may return to the standby state in which the sound wave is constantly received after the data is discarded.

When the slave unit does not receive radio waves from the master unit (203), the slave unit discards the data of the time when the sound wave was received, the frequency of the sound wave, and the waveform (205). After discarding the data, the slave unit returns to the standby state in which it constantly receives sound waves. The slave unit may be in a standby state for constantly receiving sound waves while discarding data by multithreading.

The predetermined time is usually a predetermined time according to the distance to be measured, or a time calculated by narrowing the measurement distance to a certain range by GPS or the like. The predetermined time is longer than the time it takes for the master unit to reach the slave unit after transmitting the sound wave. The predetermined time is preferably 100 ms to 250 ms.

By doing so, the distance can be measured according to the master unit that transmits sound waves at an arbitrary timing. The present invention can provide a system for measuring the distance between a master unit, which is a measuring object, and a slave unit, which is a measured object, at an arbitrary timing in a distance measuring system synchronized with standard time by GPS or the like.

(Embodiment 2)
FIG. 3 is a partial configuration diagram of the distance measuring system according to the second embodiment of the present invention. A second embodiment of the present invention will be described with reference to FIG.

The second embodiment is different from the first embodiment in that there are three or more master units. As shown in FIG. 3, the distance measuring system of the present embodiment includes at least a first master unit 301, a second master unit 303, a third master unit 305, and a slave unit 307. Although not shown, the first master unit 301, the second master unit 303, the third master unit 305, and the slave unit 307 are set to the standard time by GPS or the like as in the first embodiment. ..

The first master unit 301, the second master unit 303, and the third master unit 305 are fixed. Further, the relative positions or absolute positions (coordinate positions on the earth) of the first master unit 301, the second master unit 303, and the third master unit 305 are identified.

The first master unit 301 includes a sound wave transmitter 309 that transmits sound waves 325 as in the first embodiment. The second master unit 303 includes a sound wave transmitter 313 that transmits sound waves 329. The third master unit 305 includes a sound wave transmitter 317 that transmits sound waves 333.

The sound waves 325, 329, and 333 also use ultrasonic waves or audible sounds as in the first embodiment. However, the frequencies of the sound waves 325, 329, and 333 are different so that it can be identified from which master unit the sound waves are transmitted.

The first master unit 301 includes a radio wave transmitter 311 that transmits radio waves 327 as in the first embodiment. The second master unit 303 includes a radio wave transmitter 315 that transmits radio waves 331. The third master unit 305 includes a radio wave transmitter 319 that transmits radio waves 335.

The radio wave 327 transmits data on the time when the sound wave 325 was transmitted and the frequency and waveform of the sound wave 325. The radio wave 331 transmits data on the time when the sound wave 329 was transmitted and the frequency and waveform of the sound wave 329. The radio wave 335 transmits data on the time when the sound wave 333 was transmitted and the frequency and waveform of the sound wave 333. However, the radio waves 327, 331, and 335 can be identified from which master unit they are transmitted.

The slave unit 307 includes a sound wave receiver 321 and a radio wave receiver 323. The slave unit 307 is preferably a mobile phone device as in the first embodiment.

The slave unit 307 receives the sound wave 325 and the radio wave 327, and measures the distance between the first master unit 301 and the slave unit 307. The slave unit 307 receives the sound wave 329 and the radio wave 331, and measures the distance between the second master unit 303 and the slave unit 307. The slave unit 307 receives the sound wave 333 and the radio wave 335, and measures the distance between the third master unit 305 and the slave unit 307.

By measuring the distances from the three master units, the relative position of the slave unit 307 from the master unit can be measured in three dimensions. Further, when the absolute positions of the first master unit 301, the second master unit 303, and the third master unit 305 are known, the absolute positions of the slave units can be measured by using this embodiment.

For example, when the first master unit 301, the second master unit 303, and the third master unit 305 are installed on the wall surface of the room, the position of the slave unit 307 in the room can be measured. The x-axis, y-axis, and z-axis are orthogonal to each other, the first master unit 301 is (x1,0,0), the second master unit 303 is (0, y1,0), and the third master unit 305 is. When it is at (0,0, z1), the position of the slave unit 307 (x, y, z) is d1 for the distance from the first master unit 301, d2 for the distance from the second master unit 303, and the second. It is given by the following equation, where d3 is the distance from the master unit 305 of 3.

In the present embodiment, examples in which the frequencies of the sound waves 325, 329, and 333 are different are shown, but they may be the same. In that case, the first master unit 301, the second master unit 303, and the third master unit 305 transmit sound waves one by one at regular intervals, for example, about 250 ms.

Further, in the present embodiment, an example in which there are three or more master units is shown, but there may be two. For example, when a master unit is provided on each of the four wall surfaces orthogonal to each other in the front, rear, left, and right sides of the room, the position in the room can be measured in two dimensions.

As described above, the present invention can provide a distance measuring system for measuring the relative position of the slave unit with respect to the master unit or the absolute position of the slave unit. Further, the present invention can measure the absolute position with an accuracy of several mm, which is higher than the accuracy of GPS.

(Embodiment 3)
FIG. 4 is a partial configuration diagram of the distance measurement system according to the third embodiment of the present invention. Embodiment 3 of the present invention will be described with reference to FIG.

The third embodiment differs from the second embodiment in that there are a plurality of slave units, and at least one slave unit is shielded from at least one master unit and the distance cannot be measured directly.

As shown in FIG. 4, the present embodiment includes at least the first master unit 401, the second master unit 403, and the third master unit 405, and at least the first slave unit 407 and the second slave unit 409. To be equipped with. Although the first master unit 401, the second master unit 403, the third master unit 405, the first slave unit 407, and the second slave unit 409 are not shown, GPS and the like are the same as in the first embodiment. The internal clock is set to standard time.

The first master unit 401, the second master unit 403, and the third master unit 405 are fixed. Further, the relative positions or absolute positions (hereinafter, simply referred to as positions) of the first master unit 401, the second master unit 403, and the third master unit 405 are identified.

The first master unit 401, the second master unit 403, and the third master unit 405 include sound wave transmitters 413, 417, and 421 that transmit sound waves 433, 437, and 441, respectively, as in the second embodiment. .. Further, the first master unit 401, the second master unit 403, and the third master unit 405 are radio wave transmitters 415, 419, 423 that transmit radio waves 435, 439, and 443, respectively, as in the second embodiment. To be equipped.

The first slave unit 407 includes a sound wave receiver 425 and a radio wave receiver 427. Similar to the second embodiment, the first slave unit 407 receives the sound wave 433 and the radio wave 435, and measures the distance between the first master unit 401 and the first slave unit 407. Further, the first slave unit 407 receives the sound wave 437 and the radio wave 439, and measures the distance between the second master unit 403 and the first slave unit 407. Further, the first slave unit 407 receives the sound wave 441 and the radio wave 443, and measures the distance between the third master unit 405 and the first slave unit 407.

By knowing the distances from the first master unit 401, the second master unit 403, and the third master unit 405 whose positions are identified, the position of the first slave unit 407 is measured.

The new second slave unit 409 includes a sound wave receiver 429 and a radio wave receiver 431, and can receive radio waves and sound waves. The sound wave receiver 429 of the second slave unit 409 is the same as that of the first embodiment. The radio wave receiver 431 of the second slave unit 409 transmits radio waves of the first slave unit 407, the first master unit 401, the second master unit 403, and the third master unit 405 as in the first embodiment. It is possible to receive digital data of radio waves by matching the standard with the machine.

The second slave unit 409 wants to receive the sound wave 433 from the first master unit 401 in order to measure the position, but the sound wave 433 from the first master unit 401 is the second because of the shield 411. It does not reach the slave unit 409.

Therefore, the first slave unit 407 is changed to the master unit after the position is measured. The first slave unit 407 can transmit sound waves 445 by a sound wave transmitter (not shown). Further, the first slave unit 407 can transmit radio waves 447 by a radio wave transmitter (not shown).

As for the sound wave transmitter of the first slave unit 407, a combination of a high resolution amplifier and a speaker is preferable as in the case of the first master unit 401, the second master unit 403, and the third master unit 405. The sound wave transmitter of the first slave unit 407 may be a separate member from the first slave unit 407. Further, the sound wave transmitter of the first slave unit 407 may be an audible sound amplifier and a speaker capable of reproducing sound waves having a frequency of up to 20 kHz. Further, the sound wave transmitter of the first slave unit 407 can be shared with the sound wave receiver 425 if the actuator of the sound wave receiver 425 is a ceramic piezoelectric element or the like.

The radio wave transmitter of the first slave unit 407 transmits digital data by digital radio such as Bluetooth (registered trademark) and Wifi, like the first master unit 401, the second master unit 403, and the third master unit 405. Is possible. The radio wave 447 transmits the time when the sound wave 445 is transmitted and the waveform of the transmitted sound wave 445.

After being changed to the master unit, the first slave unit 407 transmits the sound wave 445 and the radio wave 447 carrying the frequency and waveform of the sound wave 445 and the transmission time of the sound wave 445 to the second slave unit 409. Since the mobile phone device can transmit and receive constant ultrasonic waves and radio waves, it is preferable as the first slave unit 407 that can be changed from the slave unit to the master unit.

The second slave unit 409 receives sound waves 437 and radio waves 439 from the second master unit 403, and measures the distance between the second master unit 403 and the second slave unit 409. The second slave unit 409 receives sound waves 437 and radio waves 439 from the third master unit 405, and measures the distance between the third master unit 405 and the second slave unit 409. Further, the second slave unit 409 receives the sound wave 445 and the radio wave 447 from the first slave unit 407 changed to the master unit, and measures the distance between the first slave unit 407 and the second slave unit 409. ..

Since the positions of the second master unit 403, the third master unit 405, and the first slave unit 407 are identified, the position of the second slave unit 409 can also be measured. In this way, the slave unit changed to the master unit can measure the position of the new slave unit by transmitting the data of the position of the slave unit changed to the master unit. In addition, the position of the slave unit that the sound wave does not reach can be measured by the shield.

It is preferable that the first slave unit 407, which has been changed to the master unit, uses an acceleration sensor to perform measurement when it is stationary. If the movement can be predicted using AI or the like, it is possible to measure the distance while moving.

It is preferable that the second slave unit 409 is also a mobile phone device that can be changed to a master unit like the first slave unit 407. If the slave unit can be changed to the master unit, the slave unit can be changed to the master unit and the object to be measured can be changed. When the position of the second slave unit 409 is identified, the position of another slave unit in a further hidden place can be identified. By changing the slave unit to the master unit in a chain in this way, the positions of the plurality of slave units are identified. In addition, the position of the slave unit hidden from any master unit can be identified.

Even in places where sound waves do not reach directly, positioning is possible by going through several slave units. For example, in a vast place, after measuring with the A, B, C master unit-D slave unit, it can be deployed as the B, C, D master unit-E slave unit. Alternatively, even if the slave unit is hidden in the shadow, sound waves are emitted one after another using the surrounding slave units judged by the last ranging data and radio field strength as the master unit, and the slave unit returns the acknowledge (current position by wifi etc.). You can actively search for a specific target, such as continuing the operation until (up).

In addition, like the wireless standard Zigbee and the WWW (World Wide Web) on the Internet, sound waves and wireless transmission and reception can be performed flexibly in a mesh shape, and positioning can be performed so that the positions are mutually corrected, resulting in an error (abnormality). Value) is small, and highly accurate positioning is possible. For example, after measurement with the F slave unit-G, H, I master unit, the error can be offset by switching to the G slave unit-F, H, I master unit and re-measuring, and comparing the values.

The present invention can provide a distance measurement system in which a slave unit is changed to a master unit to change an object to be measured. Further, the present invention can provide a distance measurement system that measures the position of a slave unit that is out of reach of sound waves due to a shield.

(Embodiment 4)
FIG. 5 is a partial configuration diagram of the distance measurement system according to the fourth embodiment of the present invention. A fourth embodiment of the present invention will be described with reference to FIG.

The fourth embodiment is different from the first embodiment in that the distances of a plurality of slave units are measured at the same time. As shown in FIG. 5, the present embodiment includes at least one master unit 501, and at least the first slave unit 503 and the second slave unit 505. Although not shown, the master unit 501, the first slave unit 503, and the second slave unit 505 are set to the standard time by GPS or the like as in the first embodiment.

The master unit 501 includes a sound wave transmitter 507 that transmits sound waves 519 as in the first embodiment. The master unit 501 includes a radio wave transmitter 509 that transmits radio waves 521 as in the first embodiment.

The first slave unit 503 includes a sound wave receiver 511 and a radio wave receiver 513 as in the first embodiment. The second slave unit 505 includes a sound wave receiver 515 and a radio wave receiver 517 as in the first embodiment.

The first slave unit 503 and the second slave unit 505 simultaneously receive the sound wave 519 and the radio wave 521 emitted from the master unit 501, respectively. The first slave unit 503 can receive the sound wave 519 and the radio wave 521 and measure the distance between the master unit 501 and the first slave unit 503. The second slave unit 505 can receive the sound wave 519 and the radio wave 521 and measure the distance between the master unit 501 and the first slave unit 503. Since the sound wave 519 has no directivity and the radio wave 521 also has no directivity, the distances of a plurality of slave units can be measured at the same time.

The present embodiment can be arbitrarily combined with the first to third embodiments. The present invention can provide a distance measuring system that simultaneously measures the distances of a plurality of slave units.

(Embodiment 5)
FIG. 6 is a partial configuration diagram of the distance measurement system according to the fifth embodiment of the present invention. A fifth embodiment of the present invention will be described with reference to FIG.

In the sixth embodiment, the position is measured by radio waves and sound waves from one master unit. As shown in FIG. 6, the present embodiment includes a receiver 601 and a slave unit 603, and a master unit (not shown). Although not shown, the master unit and the slave unit 603 are set to the standard time by GPS or the like as in the first embodiment.

The receiver includes at least a first sound wave receiver 605, a second sound wave receiver 607, and a third sound wave receiver 609. The first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609 are preferably high-resolution microphones capable of responding up to a frequency of 96 kHz. Further, the microphone may have a frequency of up to 20 kHz. It is preferable that the first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609 match the performance of the sound waves transmitted by the master unit. Although three sound wave receivers are shown here, it is preferable that the receiver is a cube having a side of several cm, and the sound wave receiver is omnidirectional and is located in the center of each surface.

The first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609 receive the sound wave 613 transmitted from one master unit. Since the positions of the first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609 are slightly different, the arrival time of the sound wave 613 is different.

The slave unit 603 is an information processing device, preferably a mobile phone device, for example. The slave unit 603 includes a radio wave receiver 611, and receives the radio wave 615 transmitted from one master unit. The radio wave 615 transmits data on the time when the sound wave 613 was transmitted, the frequency of the sound wave 613, and the waveform of the sound wave 613.

The distance from the master unit is obtained from the time when the sound wave 613 reaches the first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609. From the ratio of the distance to each master unit and the distances of the first sound wave receiver 605, the second sound wave receiver 607, and the third sound wave receiver 609, the relative to the master unit of the receiver 601 in three dimensions. The position can be measured. If the absolute position of the master unit is identified, the absolute position of the receiver 601 can be measured. In this way, even if there is only one master unit, the relative position or absolute position of the slave unit can be measured.

By using this embodiment, a plurality of sound wave receivers can be attached to a helmet or the like to measure the movement of the head. For example, physical condition management and fainting can be detected. Unlike a general acceleration sensor, there is no overshoot due to the inertia of the weight inside the sensor, so the movement of the head can be measured more accurately.

The present embodiment can be arbitrarily combined with the first to fourth embodiments. The present invention can provide a distance measurement system that measures the relative position of a slave unit with respect to a master unit or the absolute value of the slave unit from one master unit.

The description of the embodiments described above is exemplary in all respects and is not restrictive. Modifications and changes can be made appropriately for those skilled in the art. The scope of the present invention is indicated by the scope of claims, not by the above-described embodiment. Further, the scope of the present invention includes modifications from the embodiment within the scope of the claims and within the scope of the claims.

For example, the number of slave units and master units can be increased or decreased. Further, although the mobile phone device is exemplified as the slave unit, it may be a mobile device having other sound wave receiving function and radio wave receiving function.

The present invention can provide a system for measuring the distance between a master unit, which is a measuring object, and a slave unit, which is a measured object, at an arbitrary timing in a distance measuring system synchronized with standard time by GPS or the like.

The present invention can also provide a distance measuring system that measures the relative position of the slave unit with respect to the master unit or the absolute position of the slave unit. Further, the present invention can provide a distance measurement system in which a slave unit is changed to a master unit to change an object to be measured. Further, the present invention can provide a distance measurement system that measures the position of a slave unit that is out of reach of sound waves due to a shield.

Further, the present invention can provide a distance measuring system that simultaneously measures the distances of a plurality of slave units. The present invention can provide a distance measurement system that measures the relative position of a slave unit with respect to a master unit or the absolute value of the slave unit from one master unit.

Further, the present invention can provide a distance measuring system that technically relatively easily measures a distance or a position by using existing techniques such as a mobile phone device, GPS, NITZ, NTP, and a high resolution sound source.

By using the present invention, it is possible to perform a bird's-eye view of all the slave units at a target location, and at the same time, precisely target a specific device in the vicinity. Therefore, for example, the self-driving robot and the employee may be equipped with this device, and the robot may take evasive action against the approach of the employee by mutually measuring the distance with the surrounding employees while the robot is traveling. it can. Instead of evasive action, the robot may alert the employee. Therefore, it is possible to prevent the robot from colliding with the employee.

The present invention can search for a person with a mobile phone. For example, in a vast place such as a shopping center, a master unit can search for a lost child by speaking out and searching for a slave unit.

101 Master unit 103 Slave unit 105 Satellite 107 Sonic transmitter 109 Radio transmitter 111 Sonic receiver 113 Radio receiver 115 Sonic 117 Radio 119 GPS signal 301 First master 303 Second master 305 Third master 307 Slave unit 309 Sonic transmitter 311 Radio transmitter 313 Sonic transmitter 315 Radio transmitter 317 Sonic transmitter 319 Radio transmitter 321 Sonic receiver 323 Radio receiver 325 Sonic 327 Radio 329 Sonic 331 Radio 333 Sonic 335 Radio 401 First Master unit 403 2nd master unit 405 3rd master unit 407 1st slave unit 409 2nd slave unit 411 Obstruction 413 Sound transmitter 415 Radio transmitter 417 Sound transmitter 419 Radio transmitter 421 Sound transmitter 423 Radio transmitter 425 Sound wave receiver 427 Radio wave receiver 429 Sound wave receiver 431 Radio wave receiver 433 Sound wave 435 Radio wave 437 Sound wave 439 Radio wave 441 Sound wave 443 Radio wave 445 Sound wave 447 Radio wave 501 Master unit 503 First slave unit 505 Second slave unit 507 Sonic transmitter 509 Radio transmitter 511 Sonic receiver 513 Radio receiver 515 Sonic receiver 517 Radio receiver 519 Sonic 521 Radio 601 Receiver 603 Slave unit 605 1st Sonic receiver 607 2nd Sonic receiver 609 3rd Sonic receiver 611 Radio receiver 613 Sonic 615 Radio

Claims (11)

A master unit that transmits sound waves and transmits the time when the sound waves were transmitted by radio waves,
A distance measuring system including a slave unit that receives the sound wave and the radio wave and measures the distance from the master unit from the time when the sound wave is transmitted and the time when the sound wave is received.
The master unit and the slave unit are distance measurement systems in which the internal clock is synchronized with the standard time. The master unit transmits data of a single frequency and a plurality of frequencies and waveforms of the sound wave by the radio wave.
The slave unit constantly receives sound waves, stores the time when the sound waves are received, the frequency of the sound waves, and the waveform data of the sound waves.
The slave unit holds the data for a predetermined time,
When the slave unit does not receive the radio wave from the master unit, the data is discarded.
The slave unit receives the radio wave from the master unit, and the frequency of the sound wave and the waveform data of the sound wave transmitted by the radio wave, the frequency of the received sound wave, and the waveform data of the sound wave are approximated. The distance measuring system according to claim 1, wherein when they match or match, the distance between the master unit and the slave unit is measured. The distance measuring system according to claim 1 or 2, wherein the slave unit can be changed to the master unit. The distance measurement system according to any one of claims 1 to 3, wherein the master unit has three or more locations, and the frequencies of sound waves transmitted are different from each other. The master unit is fixed and its absolute position is identified.
The distance measuring system according to claim 4, wherein the plurality of master units can measure the absolute position of the slave unit by transmitting the absolute position of each of the master units by the radio wave. Claim 3 quoting claim 3, wherein the slave unit changed to the master unit can measure the absolute position of the new slave unit by transmitting the data of the absolute position of the slave unit changed to the master unit. The distance measuring system according to claim 5, which cites item 4. There are multiple slave units,
The distance measuring system according to any one of claims 1 to 6, which can measure the distances of a plurality of the slave units at the same time. The distance measuring system according to any one of claims 1 to 7, wherein the slave unit receives the sound waves at a plurality of locations. The distance measuring system according to any one of claims 1 to 8, wherein the slave unit includes a mobile phone device. The distance measuring system according to any one of claims 1 to 9, wherein the method of synchronizing the internal clock with the standard time uses NITZ, NTP, or GPS. The distance measurement system according to any one of claims 1 to 10, wherein the frequency of the sound wave is 16 kHz or more and 96 kHz or less.

Images