JP2023144289A - Position detection system and lighting device - Google Patents

Abstract

A position detection system capable of estimating the coordinates of an object in a predetermined space is provided. A position detection system 10 or a position detection system 10a includes a lighting device 30 installed on the ceiling of an indoor space 60, and an ultrasonic transmitter 20 attached to a moving object that moves on the floor of the indoor space 60. Equipped with The lighting device 30 includes a light source 31, a light source control unit 32 that outputs an optical ID signal by blinking the light source 31, and an ultrasonic wave emitted by the ultrasonic transmitter 20 upon receiving the optical ID signal. It includes an ultrasonic array sensor 35 and a signal processing unit 34 that detects the position of the moving body based on the received ultrasonic waves. [Selection diagram] Figure 1

Description

The present invention relates to a position detection system and a lighting device.

Patent Document 1 discloses a position detection system that can accurately determine the location of each moving object in real time even if there are a large number of moving objects.

JP2003-279640A

The present invention provides a position detection system and the like whose installation work is simplified.

A position detection system according to one aspect of the present invention includes a lighting device installed on the ceiling of a space, and an ultrasonic transmitter attached to a moving body that moves on a floor surface of the space, and the lighting device includes: a light source; a light source control unit that outputs an optical ID signal by blinking the light source; and an ultrasonic array sensor that receives ultrasonic waves emitted when the ultrasonic transmitter receives the optical ID signal; and a signal processing unit that detects the position of the mobile object based on the received ultrasonic waves.

A lighting device according to one aspect of the present invention is a lighting device installed on the ceiling of a space, and includes a light source, a light source control unit that outputs a light ID signal by blinking the light source, and a floor surface of the space. an ultrasonic array sensor that receives ultrasonic waves emitted when an ultrasonic transmitter attached to a moving body that moves receives the optical ID signal; and a signal processing unit that detects the position of.

According to the present invention, a position detection system and the like with simplified installation work are realized.

FIG. 1 is a block diagram showing the functional configuration of a position detection system according to the first embodiment. FIG. 2 is a diagram showing an indoor space to which the position detection system according to the first embodiment is applied. FIG. 3 is a diagram showing an example of the appearance of the lighting device according to the first embodiment. FIG. 4 is a sequence diagram of the operation of the position detection system according to the first embodiment. FIG. 5 is a block diagram showing the functional configuration of the position detection system according to the second embodiment. FIG. 6 is a diagram schematically showing the ultrasonic detectable areas of a plurality of illumination devices. FIG. 7 is a time chart when a position detection error occurs. FIG. 8 is a time chart showing an example 1 of the optical ID signal output operation of the position detection system according to the second embodiment. FIG. 9 is a time chart of a second example of the optical ID signal output operation of the position detection system according to the second embodiment. FIG. 10 is a diagram illustrating an example of a method for determining the predetermined time.

Embodiments will be described below with reference to the drawings. Note that the embodiments described below are all inclusive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, steps, order of steps, etc. shown in the following embodiments are merely examples, and do not limit the present invention. Further, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims will be described as arbitrary constituent elements.

Note that each figure is a schematic diagram and is not necessarily strictly illustrated. Furthermore, in each figure, substantially the same configurations are denoted by the same reference numerals, and overlapping explanations may be omitted or simplified.

(Embodiment 1)
[composition]
First, the configuration of the position detection system according to Embodiment 1 will be explained. FIG. 1 is a block diagram showing the functional configuration of a position detection system according to the first embodiment. FIG. 2 is a diagram showing an indoor space to which the position detection system according to the first embodiment is applied.

The position detection system 10 according to the first embodiment is a system that detects the position (coordinates) of a moving object moving on the floor surface of the indoor space 60 based on ultrasonic waves emitted by the ultrasonic transmitter 20. The indoor space 60 is, for example, an office space, but may also be an indoor space in another facility such as a space in a commercial facility or a space in a residence. The moving object is, for example, a living object such as a person, but may also be a tangible object (an object other than a person; for example, a non-living object) such as a shopping cart.

As shown in FIGS. 1 and 2, the position detection system 10 includes a plurality of ultrasonic transmitters 20 and a lighting device 30. Note that the position detection system 10 only needs to include at least one ultrasonic transmitter 20.

First, the ultrasonic transmitter 20 will be explained. The ultrasonic transmitter 20 emits ultrasonic waves while attached to a moving object (a person in the example of FIG. 2). The ultrasonic transmitter 20 includes, for example, a strap and is hung around a person's neck, but the specific method of attaching the ultrasonic transmitter 20 to a moving body (person) is not particularly limited. The ultrasonic transmitter 20 includes a light receiving section 21, a demodulating section 22, a control section 23, a memory 24, a driver 25, and a sound source 26.

The light receiving unit 21 receives the optical ID signal output by the lighting device 30. The light receiving section 21 is realized by a photodiode, an image sensor, or the like. In other words, the optical ID signal is a visible light communication signal, and is realized by flickering (blinking) of a light source included in the lighting device 30.

Specifically, the optical ID signal is a signal indicating the ID of the ultrasonic transmitter 20, and upon receiving the optical ID signal indicating the ID of the ultrasonic transmitter 20, the ultrasonic transmitter 20 uses this as a trigger. emits ultrasonic waves. Note that the optical ID signal is a signal modulated by a modulation method such as ASK (Amplitude Shift Keying) or PPM (Pulse Position Modulation).

The demodulator 22 is a demodulator circuit that demodulates the optical ID signal received by the light receiver 21.

The control unit 23 determines whether the optical ID signal demodulated by the demodulation unit 22 indicates the ID of the ultrasonic transmitter 20 (hereinafter also referred to as its own device) including the control unit 23, and When it is determined that it is the ID of the device, a control signal is output to the driver 25, thereby causing the sound source 26 to generate ultrasonic waves. Note that when the control unit 23 determines that the optical ID signal demodulated by the demodulation unit 22 is not the ID of the device itself, the control unit 23 does not cause the sound source 26 to generate ultrasonic waves.

The control unit 23 is specifically implemented by a processor or a microcomputer. The functions of the control section 23 are realized by a processor or a microcomputer constituting the control section 23 executing a computer program stored in the memory 24.

The memory 24 is a storage device in which computer programs and the like executed by the control unit 23 are stored. Specifically, the memory 24 is realized by a semiconductor memory or the like. The memory 24 may be built into the control unit 23.

The driver 25 is an amplifier circuit that amplifies the signal level of the control signal output by the control section 23. The control signal amplified by the driver 25 is output to the sound source 26.

The sound source 26 generates ultrasonic waves by vibrating air based on the control signal amplified by the driver 25. Specifically, the sound source 26 is realized by a thermally excited ultrasonic generating element, but may also be realized by a piezoelectric ultrasonic generating element.

Next, the lighting device 30 will be explained. The lighting device 30 is installed on the ceiling of the indoor space 60 and illuminates the indoor space 60. The lighting device 30 is, for example, a base light, but may also be a ceiling light, a spotlight, a downlight, or the like, and the specific aspect of the lighting device 30 is not particularly limited. The lighting device 30 includes a light source 31, a light source control section 32, a memory 33, a signal processing section 34, and an ultrasonic array sensor 35.

The light source 31 irradiates the indoor space 60 with white light (visible light). The light source 31 is realized by, for example, an LED (Light Emitting Diode) element, but may be realized by other light emitting elements such as a semiconductor laser, an organic EL (Electro-Luminescence), or an inorganic EL.

The light source control unit 32 controls the light emission of the light source 31. For example, the light source control unit 32 outputs the optical ID signal by making the light source 31 flicker. Note that the light source 31 blinks at a high speed while outputting the optical ID signal, and to the human eye it appears as if the light source 31 is emitting light constantly, but if the light receiving unit 21 detects this blinking as an electrical signal. can be recognized as Blinking means that the state in which the light source 31 emits light brightly and the state in which it emits darkly (or the state in which the light source 31 lights out) are repeated, and includes blinking.

The light source control unit 32 is specifically implemented by a processor or a microcomputer. The functions of the light source control section 32 are realized by a processor or a microcomputer constituting the light source control section 32 executing a computer program stored in the memory 33.

The memory 33 is a storage device that stores a computer program executed by the light source control unit 32, a computer program executed by the signal processing unit 34, and the like. Specifically, the memory 33 is realized by a semiconductor memory or the like. In FIG. 1, the memory 33 is shared by the light source control section 32 and the signal processing section 34, but the lighting device 30 includes a memory for the light source control section 32 and a memory for the signal processing section 34 separately. It's okay.

The signal processing unit 34 detects the position of the ultrasonic transmitter 20, that is, the position of the moving body, based on the ultrasonic waves received by the ultrasonic array sensor 35. Specifically, the signal processing unit 34 identifies the direction in which the ultrasonic transmitter 20 is located based on the difference in the reception timing of the ultrasonic waves in each of the plurality of wave receiving elements included in the ultrasonic array sensor 35. . Further, the signal processing unit 34 specifies the distance from the lighting device 30 to the ultrasound transmitter 20 based on the difference between the output timing of the optical ID signal and the reception timing of the ultrasound. The signal processing unit 34 can detect the position of the moving object based on the specified direction and distance.

The signal processing unit 34 is specifically implemented by a processor or a microcomputer. The functions of the signal processing section 34 are realized by a processor or a microcomputer constituting the signal processing section 34 executing a computer program stored in the memory 33.

The ultrasonic array sensor 35 includes a plurality of wave receiving elements arranged in a two-dimensional array (in other words, in a matrix), and each of the plurality of wave receiving elements receives ultrasonic waves. The wave receiving element is realized by, for example, a capacitive microphone, but may also be realized by a piezoelectric element.

The components included in the lighting device 30 described above are housed in an outer casing provided in the lighting device 30. FIG. 3 is a diagram showing an example of the appearance of the lighting device 30. As shown in FIG. 3, the light source 31 is covered with a translucent cover 36, for example. The ultrasonic array sensor 35 is covered, for example, by a non-transparent cover 37 provided with a plurality of small openings for passing ultrasonic waves.

In this manner, in the position detection system 10, the illumination device 30 that outputs the optical ID signal that is a trigger for transmitting ultrasonic waves is equipped with the ultrasonic array sensor 35 (ultrasonic receiving device). Thereby, the installation work of the device in the position detection system 10 is simplified compared to a position detection system that requires separately installing the illumination device 30 and the ultrasonic receiving device.

By the way, in the case where the sound source 26 realized by a thermally excited ultrasonic generating element has a resonance characteristic Q value of about 1, and the ultrasonic array sensor 35 is equipped with a wave receiving element realized by a capacitance type microphone. The Q value of the resonance characteristic of the wave receiving element is about 3 to 4.

According to such a configuration, the dead zone caused by reverberation components in the ultrasonic waves transmitted from the sound source 26 can be made shorter than when the sound source 26 and the wave receiving element are each realized by piezoelectric elements. . It is also possible to shorten the reverberation time of the received signal generated when the receiving element receives ultrasonic waves, thereby shortening the dead zone caused by reverberation components in the received signal output from the receiving element. be able to. Therefore, angular resolution can be improved. Note that, unlike a piezoelectric element, a capacitive microphone does not have a high Q value with resonance characteristics, so it is possible to widen the range of reception frequencies. Furthermore, the Q values of the resonance characteristics of the sound source 26 and the wave receiving element are both preferably 10 or less, and more preferably 5 or less.

[motion]
Next, the operation of the position detection system 10 will be explained. FIG. 4 is a sequence diagram of the operation of the position detection system 10. In the following description of FIG. 4, the ultrasonic transmitter 20 attached to the mobile body 1 will be referred to as an ultrasonic transmitter 1, and the ultrasonic transmitter 20 attached to the mobile body 2 will be referred to as an ultrasonic transmitter 2. It is written as. It is assumed that the ID of the ultrasonic transmitter 1 is 001 and the ID of the ultrasonic transmitter 2 is 002.

The light source control unit 32 of the lighting device 30 generates a plurality of optical ID signals (an optical ID signal indicating ID001) corresponding to the IDs of the plurality of ultrasonic transmitters 20 (ultrasonic transmitters 1 and ultrasonic transmitters 2), and (optical ID signal indicating ID002) are output in order. For example, the light source control unit 32 outputs a light ID signal indicating ID001 by blinking the light source 31 (S11). At this time, the light source control unit 32 stores the output timing of the optical ID signal in the memory 33.

When the optical ID signal is received by the light receiving unit 21 of the ultrasonic transmitter 1, the control unit 23 of the ultrasonic transmitter 1 determines that the ID indicated by the optical ID signal is ID001 (this is the ID of the own device). After making a determination, ultrasonic waves are emitted via the driver 25 and sound source 26 (S12). That is, the control unit 23 of the ultrasonic transmitter 1 emits ultrasonic waves upon receiving the optical ID signal indicating ID001.

On the other hand, when the optical ID signal is received by the light receiving unit 21 of the ultrasonic transmitter 2, the control unit 23 of the ultrasonic transmitter 2 determines that the ID indicated by the optical ID signal is not ID002 (it is not the ID of the own device). ) and does not emit ultrasound.

When the ultrasonic waves emitted in step S12 are received by the ultrasonic array sensor 35, the signal processing unit 34 of the illumination device 30 determines the position of the ultrasonic transmitter 1, that is, the movement thereof, based on the received ultrasonic waves. The position of the body 1 is detected (S13). Specifically, the signal processing unit 34 identifies the direction in which the ultrasonic transmitter 1 is located based on the difference in the reception timing of the ultrasonic waves in each of the plurality of wave receiving elements included in the ultrasonic array sensor 35. . Further, the signal processing unit 34 specifies the distance from the lighting device 30 to the ultrasound transmitter 1 based on the difference between the output timing of the optical ID signal and the reception timing of the ultrasound.

Here, the installation position of the lighting device 30 in the indoor space 60 (more specifically, the coordinates of the ultrasonic array sensor) is stored in the memory 33 in advance. The signal processing unit 34 can detect the position (coordinates) of the moving object 1 based on the installation position of the lighting device 30, the specified direction, and the specified distance. The detected position (coordinates) is stored in the memory 33 in association with the current time and ID001.

Next, the light source control unit 32 of the lighting device 30 outputs a light ID signal indicating ID002 by blinking the light source 31 (S14). At this time, the light source control unit 32 stores the output timing of the optical ID signal in the memory 33.

When the optical ID signal is received by the light receiving unit 21 of the ultrasonic transmitter 1, the control unit 23 of the ultrasonic transmitter 1 determines that the ID indicated by the optical ID signal is not ID001 (not the ID of the own device). judgment and do not emit ultrasound.

On the other hand, when the optical ID signal is received by the light receiving unit 21 of the ultrasonic transmitter 2, the control unit 23 of the ultrasonic transmitter 2 determines that the ID indicated by the optical ID signal is ID002 (this is the ID of the own device). ), and an ultrasonic wave is emitted via the driver 25 and sound source 26 (S15). That is, the control unit 23 of the ultrasonic transmitter 2 emits ultrasonic waves upon receiving the optical ID signal indicating ID002.

When the ultrasonic waves emitted in step S15 are received by the ultrasonic array sensor 35, the signal processing unit 34 of the illumination device 30 determines the position of the ultrasonic transmitter 2, that is, the movement thereof, based on the received ultrasonic waves. The position of the body 2 is detected (S16). Specifically, the signal processing unit 34 identifies the direction in which the ultrasonic transmitter 2 is located based on the difference in the reception timing of the ultrasonic waves in each of the plurality of wave receiving elements included in the ultrasonic array sensor 35. . Further, the signal processing unit 34 specifies the distance from the lighting device 30 to the ultrasound transmitter 20 based on the difference between the output timing of the optical ID signal and the reception timing of the ultrasound.

The signal processing unit 34 can detect the position (coordinates) of the moving object 2 based on the installation position of the lighting device 30, the specified direction, and the specified distance. The detected position (coordinates) is stored in the memory 33 in association with the current time and ID002.

The output of the light ID by the light source control unit 32 is periodically repeated. Therefore, the memory 33 stores time-series data of the position of the mobile body 1 (ultrasonic transmitter 1) and time-series data of the position of the mobile body 2 (ultrasonic transmitter 2). If such time series data is taken out from the lighting device 30 to a personal computer or the like, flow line analysis using the time series data becomes possible.

As explained above, in the position detection system 10, the signal processing unit 34 of the illumination device 30 distinguishes the position of the mobile body 1 from the position of another mobile body 2 based on the output timing of the plurality of optical ID signals. can be detected separately.

(Embodiment 2)
[composition]
Next, the configuration of the position detection system according to the second embodiment will be explained. FIG. 5 is a block diagram showing the functional configuration of the position detection system according to the second embodiment.

As shown in FIG. 5, the position detection system 10a according to the second embodiment includes a plurality of ultrasonic transmitters 20, a plurality of lighting devices 30, a control computer 40, and a hub 50. Note that the number of ultrasonic transmitters 20 and the number of lighting devices 30 included in the position detection system 10a are not particularly limited.

The ultrasonic transmitter 20 and the illumination device 30 have the same configuration as in Embodiment 1, so a detailed explanation will be omitted. Note that the position detection system 10a can detect the position of a moving object by performing the same operation as the position detection system 10.

The control computer 40 outputs time information for synchronizing the plurality of lighting devices 30. The time information is broadcasted to the plurality of lighting devices 30 via the hub 50.

The control computer 40 is connected to the input port of the hub 50, and the lighting device 30 is connected to each of the plurality of output ports. Note that the communication standard between the control computer 40 and the plurality of lighting devices 30 is, for example, EIA-232-E, but other communication standards may be used.

[Optical ID signal output operation example 1]
In a system in which a plurality of illumination devices 30 exist, such as the position detection system 10a, the areas where the plurality of illumination devices 30 can detect ultrasonic waves may overlap. FIG. 6 is a diagram schematically showing the ultrasonic detectable areas of the plurality of illumination devices 30. In addition, in FIG. 6, the plurality of lighting devices 30 are distinguished by symbols such as lighting device 30a and lighting device 30b.

In FIG. 6, an ultrasonic detectable area A of the lighting device 30a and an ultrasonic detectable area B of the lighting device 30b are illustrated. Here, as shown in FIG. 6, if mobile object 1 exists in area C where area A and area B overlap, and mobile object 2 exists in area B, the position detection of the mobile object is performed as follows. Errors can occur. FIG. 7 is a time chart when a position detection error occurs.

As shown in FIG. 7, when the lighting device 30a is outputting a light ID signal indicating ID001 ((a) in FIG. 7), the lighting device 30b is outputting a light ID signal indicating ID002. ((c) in Figure 7). The ultrasonic transmitter 2 attached to the moving body 2 emits ultrasonic waves upon receiving the optical ID signal output by the lighting device 30b. Here, since the mobile object 2 is located outside area A and within area B, the ultrasonic waves emitted by the ultrasonic transmitter 2 are transmitted to the ultrasonic array sensor 35 of the illumination device 30b. ((d) in FIG. 7), but does not reach the ultrasonic array sensor 35 of the illumination device 30a.

On the other hand, the ultrasonic transmitter 1 attached to the moving body 1 emits ultrasonic waves upon receiving the optical ID signal output by the lighting device 30a. Here, since the mobile object 1 is located in area C which is within area A and also within area B, the ultrasound emitted by the ultrasound transmitter 1 is transmitted to the ultrasound array of the illumination device 30a. It reaches the sensor 35 ((b) in FIG. 7), and further reaches the ultrasonic array sensor 35 of the lighting device 30b ((d) in FIG. 7).

Then, in response to the illumination device 30b outputting the optical ID signal, the ultrasonic array sensor 35 of the illumination device 30b detects the ultrasonic waves emitted by the ultrasonic transmitter 1 and the ultrasonic transmitter 2. The device receives ultrasonic waves.

Therefore, in the position detection system 10a, the illumination device 30a and the illumination device 30b are synchronized so that they output optical ID signals indicating the same ID at the same timing based on the time information output by the control computer 40. Operate. FIG. 8 is a time chart showing example 1 of such an optical ID signal output operation. According to the first optical ID signal output operation example, occurrence of position detection errors as shown in FIG. 7 is suppressed. Note that the same timing here does not mean strictly the same, but means substantially the same.

[Optical ID signal output operation example 2]
In the first example of the optical ID signal output operation shown in FIG. There is a possibility that the ultrasonic transmitter 20 located at a place where it can receive the two optical ID signals will not be able to receive the optical ID signal.

Therefore, in the position detection system 10a, each of the lighting device 30a and the lighting device 30b outputs the plurality of optical ID signals in the same order at a period of T+α. FIG. 9 is a time chart of example 2 of such an optical ID signal output operation.

T is a period of fixed length, for example 0.8 seconds. α is an adjustment amount determined based on uniformly distributed random numbers, and its value changes every time the optical ID signal is output. α is, for example, an arbitrary value in the range of −0.2 seconds or more and 0.2 seconds or less. Note that the absolute value of α is smaller than the absolute value of T.

According to the second example of the optical ID signal output operation, the output timing of the optical ID signals of the lighting device 30a and the lighting device 30b tends to shift due to the adjustment amount α. , successive occurrences of collisions between two optical ID signals are suppressed. Therefore, even if the ultrasonic transmitter 20 is unable to receive an optical ID signal due to a collision between two optical ID signals, the possibility of receiving the next optical ID signal is increased.

[Limit on time until ultrasound is received]
By the way, it is assumed that a place like area C in FIG. 6 and a place where the collision of the optical ID signals occurs is often a place far from both the lighting device 30a and the lighting device 30b. . Therefore, the signal processing section 34 may invalidate the ultrasonic waves emitted by the ultrasonic transmitter 20 located far from the lighting device 30 including the signal processing section 34 . Specifically, when the signal processing unit 34 receives an ultrasonic wave after a predetermined time has elapsed from the output timing of the optical ID signal, the signal processing unit 34 treats the ultrasonic wave as invalid and determines the position of the moving body based on the ultrasonic wave. No detection is required.

In detecting the position of a moving body, it is necessary to store in the memory 33 the waveforms of ultrasound waves received by each of the plurality of wave receiving elements, but according to the above configuration, unnecessary waveforms of ultrasound waves are discarded. and is not stored in the memory 33, the capacity of the memory 33 can be effectively utilized.

The predetermined time is determined, for example, as shown in FIG. FIG. 10 is a diagram illustrating an example of a method for determining the predetermined time. If the height from the floor to the ceiling is h and the range of 60° from the lighting device 30 is defined as the effective range, then the ultrasonic waves from the ultrasonic transmitter 20 located further away than the point P in FIG. 10 will be discarded. That's fine.

The distance from the installation position of the lighting device 30 to point P is 2 hours, and the time required for the ultrasonic transmitter 20 located at point P to emit an ultrasonic wave immediately after receiving the optical ID signal is equal to the speed of sound. Assuming that 340 [m/s], it becomes 2×2h/340. Let t be the time required for processing from when the ultrasonic transmitter 20 receives the optical ID signal until it emits an ultrasonic wave, then after the ultrasonic transmitter 20 located at point P receives the optical ID The time required to emit ultrasonic waves is t+2×2h/340. The predetermined time is determined, for example, based on this formula. Note that when h=3 [m], the predetermined time is t+35.3 [ms].

Note that such a configuration in which the time from outputting the optical ID signal to receiving the ultrasonic wave is limited can be realized not only in the position detection system 10a but also in the position detection system 10.

(summary)
As explained above, the position detection system 10 or the position detection system 10a includes the lighting device 30 installed on the ceiling of the indoor space 60 and the ultrasonic transmitter attached to a moving object that moves on the floor of the indoor space 60. 20. The lighting device 30 includes a light source 31, a light source control unit 32 that outputs an optical ID signal by blinking the light source 31, and receives ultrasonic waves emitted when the ultrasonic transmitter 20 receives the optical ID signal. It includes an ultrasonic array sensor 35 and a signal processing unit 34 that detects the position of the moving body based on the received ultrasonic waves.

The installation work of the position detection system 10 or the position detection system 10a is simplified because the illumination device 30 that outputs the optical ID signal includes the ultrasonic array sensor 35. In other words, the position detection system 10 or the position detection system 10a is useful as a position detection system whose installation work is simplified.

Further, for example, the position detection system 10 or the position detection system 10a includes a plurality of ultrasonic transmitters 20. Each of the plurality of ultrasound transmitters 20 emits ultrasound upon receiving an optical ID signal indicating the ID of the ultrasound transmitter 20. The light source control unit 32 sequentially outputs a plurality of optical ID signals corresponding to the IDs of the plurality of ultrasound transmitters 20. The signal processing unit 34 distinguishes and detects the position of a moving object and the position of another moving object based on the output timing of a plurality of optical ID signals.

Such a position detection system 10 or position detection system 10a can distinguish and detect the positions of a plurality of moving objects.

Further, for example, the position detection system 10a includes a plurality of lighting devices 30. Each of the plurality of lighting devices 30 outputs a plurality of optical ID signals in the same order, and the plurality of lighting devices are synchronized so as to output the optical ID signals indicating the same ID at the same timing.

Such a position detection system 10a can suppress occurrence of position detection errors as shown in FIG.

Further, for example, the position detection system 10a includes a plurality of lighting devices 30. Each of the plurality of lighting devices 30 is synchronized with the other lighting devices 30 and outputs a plurality of optical ID signals in the same order with a period having a fixed length adjusted by an adjustment amount based on a random number.

Such a position detection system 10a can reduce the frequency of collisions of optical ID signals output by the plurality of lighting devices 30.

Further, for example, when the signal processing unit 34 receives an ultrasound after a predetermined time has elapsed from the output timing of the optical ID signal, the signal processing unit 34 does not detect the position of the moving body based on the ultrasound.

Such a position detection system 10 or position detection system 10a can suppress erroneous detection of the position of a moving body.

Further, for example, the moving object is a person, and the ultrasonic transmitter 20 further includes a strap for attaching the ultrasonic transmitter 20 to the person.

Such a position detection system 10 or position detection system 10a can detect the position of a person.

Further, the lighting device 30 is a lighting device installed on the ceiling of the indoor space 60. The lighting device 30 includes a light source 31, a light source control unit 32 that outputs an optical ID signal by blinking the light source 31, and an ultrasonic transmitter 20 attached to a moving object that moves on the floor of an indoor space 60. It includes an ultrasonic array sensor 35 that receives ultrasonic waves emitted upon receiving an ID signal, and a signal processing unit 34 that detects the position of a moving body based on the received ultrasonic waves.

Such a lighting device 30 can simplify the installation work of the position detection system 10 or the position detection system 10a.

(Other embodiments)
Although the position detection system according to the embodiment has been described above, the present invention is not limited to the above embodiment.

Further, in the above embodiments, the position detection system is realized by a plurality of devices, but it may be realized as a single device. When the position detection system is realized by a plurality of devices, each component included in the position detection system may be distributed to the plurality of devices in any manner. For example, the position detection system may further include a server device, and some or all of the functions of the signal processing unit included in the lighting device may be provided by the server device.

Further, in the above embodiments, the processing executed by a specific processing unit may be executed by another processing unit. Further, the order of the plurality of processes may be changed, or the plurality of processes may be executed in parallel.

Furthermore, in the embodiments described above, each component may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

Moreover, each component may be realized by hardware. For example, each component may be a circuit (or integrated circuit). These circuits may constitute one circuit as a whole, or may be separate circuits. Further, each of these circuits may be a general-purpose circuit or a dedicated circuit.

Further, general or specific aspects of the present invention may be implemented in a system, apparatus, method, integrated circuit, computer program, or computer readable storage medium such as a CD-ROM. Further, the present invention may be realized by any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

For example, the present invention may be implemented as a position detection method executed by a computer such as a position detection system. Further, the present invention may be realized as a program for causing a computer to execute a position detection method, or may be realized as a computer-readable non-temporary recording medium in which such a program is stored. .

Other embodiments may be obtained by making various modifications to each embodiment that those skilled in the art can think of, or may be realized by arbitrarily combining the components and functions of each embodiment without departing from the spirit of the present invention. The present invention also includes such forms.

10, 10a position detection system 20 ultrasonic transmitter 21 light receiver 22 demodulator 23 controller 24 memory 25 driver 26 sound source 30, 30a, 30b illumination device 31 light source 32 light source controller 33 memory 34 signal processor 35 ultrasonic array sensor 36 Translucent cover 37 Non-transparent cover 40 Control computer 50 Hub 60 Indoor space (space)

Claims (7)

A lighting device installed on the ceiling of the space,
an ultrasonic transmitter attached to a moving body that moves on the floor of the space,
The lighting device includes:
a light source and
a light source control unit that outputs an optical ID signal by blinking the light source;
an ultrasonic array sensor that receives ultrasonic waves emitted when the ultrasonic transmitter receives the optical ID signal;
A position detection system, comprising: a signal processing unit that detects the position of the mobile object based on the received ultrasonic wave. The position detection system includes a plurality of the ultrasonic transmitters,
Each of the plurality of ultrasound transmitters emits the ultrasound upon receiving the optical ID signal indicating the ID of the ultrasound transmitter,
The light source control unit sequentially outputs the plurality of optical ID signals corresponding to the IDs of the plurality of ultrasonic transmitters,
The position detection system according to claim 1, wherein the signal processing unit detects the position of the mobile body and the position of another mobile body while distinguishing them from each other based on output timings of the plurality of optical ID signals. The position detection system includes a plurality of the lighting devices,
Each of the plurality of lighting devices outputs the plurality of optical ID signals in the same order,
The position detection system according to claim 2, wherein the plurality of lighting devices are synchronized so as to output the optical ID signals indicating the same ID at the same timing. The position detection system includes a plurality of the lighting devices,
Each of the plurality of lighting devices is synchronized with the other lighting devices and outputs the plurality of optical ID signals in the same order with a period having a fixed length adjusted by an adjustment amount based on a random number. The position detection system according to claim 2. The position detection according to claim 1, wherein the signal processing unit does not detect the position of the moving object based on the ultrasound when the ultrasound is received after a predetermined time has elapsed from the output timing of the optical ID signal. system. The moving object is a person,
The position detection system according to any one of claims 1 to 5, wherein the ultrasonic transmitter further includes a strap for attaching the ultrasonic transmitter to the person. A lighting device installed on the ceiling of a space,
a light source and
a light source control unit that outputs an optical ID signal by blinking the light source;
an ultrasonic array sensor that receives ultrasonic waves emitted when an ultrasonic transmitter attached to a moving body moving on a floor surface of the space receives the optical ID signal;
A lighting device comprising: a signal processing unit that detects the position of the moving object based on the received ultrasonic wave.

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