JP2000275321A - Method and system for measuring position coordinate of traveling object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically find the position coordinate of a traveling object in a specific target area for measurement in real time by utilizing radio waves. SOLUTION: A system for measuring position coordinate of traveling object is provided with a plurality of fixed devices 20A-20D which are arranged at different positions and generate and transmit original signals for measurement to a specific target area for measurement by using radio waves; a movable device 30 which is held by a traveling object M, calculates the receiving intensity levels of the received original signals for measurement, and generates the calculated results as measurement data signals by using radio waves; and a central controller 10 which receives the measurement data signals from the movable device 30. The controller 30 finds the position coordinate of the traveling object M by performing arithmetic processing for finding the position coordinate of the object M in the target area by collating the receiving intensity level calculated by means of the movable device 30 from the measurement data signals with reference information indicating the relation between the distance to the corresponding fixed device and the receiving intensity level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring position coordinates of a moving object, and more particularly to a method for detecting the position of a moving object that moves freely or irregularly in a specific area in the area. And a method and apparatus for measuring position coordinates of a moving object.

[0002]

2. Description of the Related Art In general, for a moving object that moves freely or irregularly in a specific area, such as a specific person or animal on a stage, an automatic traveling robot in a factory, etc., its current position is detected in real time. May be required to do so.

For example, on the stage of a theater or the like, when a specific performer arrives at a specific place, that fact is used as a cue signal (motivation signal) and a specific lighting effect, sound effect,
There is a great demand that various stage effects such as changes in stage equipment be started. Therefore, if the position of the performer can be automatically detected in real time, the detection signal can be used as a direct or indirect cue signal for starting a specific effect.
It is very reasonable and very convenient in practice. In addition, if the current position of the automatic traveling robot in the factory can be automatically detected in real time, the automatic traveling robot is controlled in a state where the maximum efficiency is obtained at that time by combining with the traveling control program. It becomes possible.

Conventionally, as a method of automatically detecting the position of a moving object in a specific area in real time, for example, a method using an ultrasonic wave, a method using a radio wave, or processing image information including a moving object is used. There are known methods.

A method of detecting the position of a moving body by using ultrasonic waves is to hold an ultrasonic transmitter on the moving body and arrange a plurality of ultrasonic detectors at different positions in a measurement target area. By measuring the time difference between the time at which the ultrasonic waves emitted from the moving body reach the respective ultrasonic detectors and are detected, distance information from the position of each ultrasonic detector to the moving body is obtained. Is used to detect the position of the moving object. However, in this method, since the capacity of the ultrasonic wave transmitter that can be held by the moving body is limited, it is not possible to obtain a large distance of the ultrasonic wave, and therefore, the ultrasonic wave with a high arrangement density in the measurement target area. There is a problem that it is necessary to install a detector, and eventually, it is necessary to install a large number of ultrasonic detectors, which is not practical.

In the method of detecting the position of a moving object by processing image information, a program for processing the image information is complicated, requires a great deal of cost, and requires a long time for required information processing. In many cases, there is a problem that reliability is low in terms of detection accuracy and speed.

On the other hand, as a method for detecting the position of a moving object using radio waves, there are, for example, a car navigation system and a ship position specifying system. These systems specify the position of a moving object with a wide area as a target area. For example, a system that detects the direction of a marker radio wave arriving from a wireless station at a specific position is known.

However, for example, indoor space in a building,
In an outdoor theater or a limited relatively narrow area, for example, an area where the longest distance is 1 km or less, radio waves are transmitted to detect the current position of a moving object that moves freely or irregularly within the area. Attempting to use it turned out to be a major obstacle due to the nature of the radio waves.

That is, in a short distance region where the distance from the radio wave transmission source is relatively small, the intensity of the received radio signal is
In essence, even if the function is a function of distance, it does not actually change according to distance or according to a certain law, but vibrates quite irregularly, In addition, no regularity is recognized in the mode of the vibration. In addition, in the short-distance region, the environmental conditions specific to the region have a great effect on the propagation of radio waves. For this reason, for example, in a system in which radio waves transmitted from a plurality of locations are received by one receiver, it is actually meaningful to measure the reception intensity level and detect the state of the attenuation, for example. No results can be obtained.

[0010]

SUMMARY OF THE INVENTION The present invention is based on the above-mentioned circumstances, and as a result of various studies, as a result, a receiver which moves a radio wave emitted from a radio wave transmitter provided at a fixed position is used. The reception intensity level when receiving a signal has an area that vibrates irregularly depending on the distance from the radio wave transmitter, but the pattern (or profile) of the change in the reception intensity level due to a change in position in the vibration area is essentially. It has been found based on this finding that they have the same identity.

An object of the present invention is to provide a method of measuring the position coordinates of a moving object, which can automatically determine the position coordinates of the moving object in a specific measurement target area using radio waves in real time. . Another object of the present invention is to provide an apparatus for measuring the position coordinates of a moving object that can automatically determine the position coordinates of the moving object in a specific measurement target area using radio waves in real time.

[0012]

According to the present invention, there is provided a method of measuring position coordinates of a moving object, the method comprising measuring position coordinates of a moving object moving within a specific measuring object area, in the measuring object area. A plurality of fixing devices that emit an original signal for measurement by radio waves in the measurement target area are fixedly arranged at different positions, receive the original signal for measurement, and calculate the reception intensity level of the received original signal for measurement. A movable unit that emits a result as a measurement data signal by radio waves is held by the moving body, and a central control unit that receives the measurement data signal from the movable unit is provided. The reception intensity level is to be compared with reference information that has been determined in advance and that has a relationship between the distance and the reception intensity level with the arrangement position of the corresponding fixing device as a reference position. Ri, and performs the arithmetic processing for obtaining the position coordinates of the measurement target region of the moving object.

In the above method, the reference information corresponds to each fixing device, and the reference information for each fixing device divides a measurement target region into a number of unit regions and continuously arranges them in one line. A group of two or more unit areas is defined as a unit area series, and for each unit area belonging to this unit area series, the operation of measuring the reception intensity level of the original signal for measurement by the fixing device and obtaining the series reference information is a different unit. It can be an aggregate of series reference information on a plurality of unit area series, obtained by performing on the area series.

[0014] The series reference information is divided into a plurality of divided areas so that one divided area does not have a plurality of portions of the same intensity level.
In the central control unit, a division area including a location of the intensity level corresponding to the reception intensity level is selected as a control division area, and in this comparison division area, the position coordinates of the location of the intensity level corresponding to the reception intensity level are determined. It is preferable that the calculation processing to be performed is performed. In the series reference information, it is preferable that a curve representing an intensity level is subjected to linearization correction processing in units of the divided areas.

In the method for automatically measuring the position coordinates of a moving object in which a measurement operation for obtaining the position coordinates of the moving object in a measurement target area is repeatedly performed, a plurality of points having the same intensity level exist in one series reference information. Of the candidate sub-areas, the sub-area including the position coordinates obtained by the previous measurement operation or the sub-area closest to the sub-area is preferably selected as the control sub-area.

Further, in the method for automatically measuring the position coordinates of a moving object in which a measurement operation for obtaining the position coordinates of the moving object in a measurement target area is repeatedly performed, a plurality of points having the same intensity level exist in one series reference information. Of the candidate sub-areas, the sub-area having the same or the closest relation to the magnitude relation of the intensity levels of the different fixing devices for the position coordinates obtained by the previous measurement operation is selected as the control sub-area. Preferably.

The position coordinate measuring device for a moving object according to the present invention is a device for measuring the position coordinates of a moving object moving within a specific measurement target region in the measurement target region. A plurality of fixing devices fixedly arranged at different positions, which emit an original signal for measurement by
A movable unit held by the moving body, which receives a measurement original signal, calculates a received intensity level of the received measurement original signal, and emits the result as a measurement data signal by radio waves, and a measurement from the movable unit. A central control unit for receiving a data signal, wherein the central control unit determines a reception intensity level of the movable unit obtained from the measured data signal in advance, and sets a corresponding fixed unit arrangement position as a reference position. By comparing the reference information with the content of the relationship between the distance and the intensity level, an arithmetic process for calculating the position coordinates of the moving object in the measurement target area is performed.

In the above apparatus, it is preferable that the original measurement signals from the respective fixing devices are radio waves having substantially the same frequency and output level. Further, it is preferable that the measurement original signal from each fixing device is a radio wave having a frequency of 150 MHz or less. Further, it is preferable that the measurement original signal from each fixing device is pulse-shaped, and one pulse waveform has a high-level portion having a high intensity level and a low-level portion having a low intensity level.

[0019]

According to the method and apparatus for measuring the position coordinates of a moving object according to the present invention, an original signal for measurement by radio waves emitted from a fixed device is received by a movable device held by the moving object, and the reception intensity level at this time is determined by: In the central controller, by comparing with the reference information containing the relationship between the distance and the intensity level with the position where the fixing device is located as the reference position, which has been obtained in advance, the fixed device of the movable device Distance information can be obtained. This is because there is a region where the reception intensity level largely fluctuates, but the pattern (or profile) of the change of the reception intensity level with respect to the distance from the fixed device has essentially the same identity. This is because the location of the intensity level corresponding to the reception intensity level corresponds to the location where the movable unit exists. as a result,
Since the distance information to the position of the movable device can be obtained from the position of the fixed device as a reference position, the distance information from the plurality of fixed devices provided at different positions is combined and arithmetically processed to obtain the movable device. , That is, the position coordinates of the moving body. Moreover, since the transmission and reception of signals are performed by radio waves or electrical communication, the position coordinates of the moving object can be obtained in real time.

By forming the reference information as an aggregate of series reference information relating to one fixing device, arithmetic processing for comparison becomes easy, and the intensity level is included in one series reference information. Even when there are a plurality of the same places, the area can be divided into a plurality of divided areas so that no two or more places of the same intensity level exist in one divided area. In addition, the position coordinates of the moving object can be measured with high accuracy.

Further, since the measurement operation for obtaining the position coordinates of the moving object in the measurement target area is usually performed repeatedly, a plurality of candidate division areas having the same intensity level in one series reference information can be obtained. From among them, the method of selecting the divided area containing the position coordinates obtained by the previous measurement operation or the divided area closest to this as the control divided area, or the position coordinates obtained by the previous measurement operation By using a method of selecting a divisional area having the same or the closest relation to the magnitude relation of the reception intensity levels of the different fixed devices as the reference divisional area, the position coordinates of the target location can be obtained very reliably and rationally. be able to.

In the moving object position coordinate measuring apparatus of the present invention, since the frequency and the output level of the radio wave relating to the original signal for measurement from each fixing device are substantially the same, the movable device should correspond. The range of the radio wave is narrowed, and as a result, the configuration of the movable unit can be simplified.

When the original signal for measurement from the fixing device is a radio wave having a frequency of 150 MHz or less, there is practically no possibility of interference and the position coordinates can be measured with high accuracy. Become. Further, the original signal for measurement from each fixing device is pulse-shaped, and one pulse is
When there is a high level portion with a high intensity level and a low level portion with a low intensity level, it is possible to stably detect the reception intensity level even if there is a change in environmental conditions.

[0024]

FIG. 1 is an explanatory view schematically showing an example of the configuration of a position coordinate measuring apparatus for a moving object according to the present invention.
FIG. 1 is a block diagram schematically showing the outline of main functional portions constituting a position coordinate measuring device of a moving object according to the present invention and the state of their connection. As shown in FIG. 1, in this apparatus, a specific measurement target region P is defined, and a plurality of fixing devices are fixedly arranged at different positions along, for example, the periphery of the measurement target region P. Is done. In the example of this figure, the measurement target area P is a rectangular indoor area, and four fixing devices 20A, 20B, 20C, and 20D are arranged at each corner of the measurement target area P. Actual measurement target areas include, for example, theaters and halls, banquet halls,
Alternatively, it is a site of a factory or other area where the moving body moves, and an area where the position coordinates of the moving body should be obtained for an appropriate purpose.

The position of the plurality of fixing devices varies depending on the shape of the area to be measured, the physical environment such as the presence of an object that affects the arrival of radio waves, and other conditions. It is preferable that the entire area be located at a position that is uniformly covered by radio waves. For example, a position where the individual fixers face the central part of the measurement target area from different directions, or a position where the individual fixers are separated from each other by a large distance can be the arrangement position of the fixers. The specific location of the fixing device is not particularly limited,
For example, in the case of a room, for example, a ceiling in the room,
It may be installed at a wall, floor, pillar, or other appropriate fixed position, but may be a temporary type.

Each of the fixing devices 20A to 20D has an antenna and is connected to the central control device 10. The fixed devices 20A to 20D have a function of generating a pulse-like original signal for measurement by radio waves in response to a transmission command signal from the central control device 10. Have. FIG.
FIG. 3 is a curve diagram showing the temporal situation of the pulse of the measurement original signal of each of these fixers 20A to 20D.
(D) shows the original measurement signal pulses a to d from the fixers 20A to 20D, respectively, and (e) shows the explanatory curves obtained by superimposing the curves (a) to (d) on a common time axis. FIG. Specifically, the transmission command signal from the central control device 10 is applied to the fixing devices 20A to 20D, and in this example, in this example, the measuring original signal pulses are sequentially output from the fixing devices 20A, 20B, 20C, and 20D. a, b, c and d
Are emitted as a pulse group.

In the above, the measurement original signal pulses a to d
The time width t of each pulse is not particularly limited, but is, for example, 10 msec. Further, a pause period N is provided between the last measurement original signal pulse d of one pulse group and the first measurement original signal pulse a of the next pulse group.
And the time width of the pause period N is not particularly limited, but is, for example, 10 msec.

A movable unit 30 is carried or held by a movable body M that moves within the measurement target area P. The movable unit 30 has a radio wave receiving function, a radio wave transmitting function, and an arithmetic processing function. The movable unit 30 receives original measurement signals from the fixing units 20A to 20D, performs an arithmetic process on the reception intensity levels of the respective signals, and obtains the result. The measurement data to be transmitted are collectively transmitted as a measurement data signal by radio waves during the pause period N.

In the measurement area P, a controller 40 having a radio wave receiving function and a radio wave transmitting function for controlling the operation of the movable unit 30 is fixedly arranged. The position of the controller 40 is determined by the movable unit 3 in the measurement target area P.
The position is not particularly limited as long as it is a position where communication can be performed with 0. For example, the position can be the same as that of one of the fixing devices. In this case, there is an advantage that the installation work is easy. is there.

The controller 40 is connected to the central controller 10 and receives a trigger command signal from the controller 40 to generate a trigger signal by radio waves, and receives a measurement data signal by radio waves from the movable unit 30 and 10.

As shown in FIG. 2, the central control unit 10
It has a drive control unit 12, an arithmetic processing unit 14, and a reference information storage unit 16. The drive control unit 12 includes a
And has a function of controlling the operation of the controller 40. Specifically, each of the fixers 20 issues a transmission command signal so as to emit the original signal pulses for measurement in a certain order, and at the same time, the controller 40 is triggered. Issues a command signal. The transmission frequency of the trigger command signal is, for example, 20 to 50 per second.
Times.

The arithmetic processing unit 14 receives the measurement data signal transmitted from the controller 40 and refers to the measurement data signal with reference information stored in the reference information storage unit 16 as described later. And a function of executing a calculation process for calculating the position coordinates of the movable unit 30 in the measurement target region P according to a predetermined process.

In the above, the frequencies of the radio waves of the measurement original signal, the trigger signal and the measurement data signal from the fixing device 20 are not particularly limited, but the frequencies of the radio waves of the trigger signal and the measurement data signal are measured. It is preferable that the frequency can be clearly identified from the frequency of the radio wave of the original signal. In practice, the frequency of the radio wave of the original signal for measurement is usually 150M
Hz or less, for example, about 50 MHz or about 10 MHz. The frequencies of the radio waves of the trigger signal and the measurement data signal are, for example, 250 to 3
It can be 50 MHz. In addition, the central controller 1
0 and each of the fixed devices 20A to 20D and the controller 40 may be connected so as to enable data communication with each other, and may be either a wired connection or a wireless connection.

In the present invention, the reference information has a function similar to a calibration curve in chemical analysis.
Specifically, it is obtained as follows. (1) Set plane coordinates in the measurement target area P. The type and content of the specific coordinates of the plane coordinates are completely arbitrary, but most simply, the plane coordinates on the normal X axis and Y axis may be used. One unit of coordinates may be set according to the target measurement position accuracy, and is not particularly limited. The actual size of the coordinate unit is the measurement target area P
The distance in one coordinate unit in the X direction and the Y direction is, for example, 30 to 500 cm, although it depends on the size of the area of
Should be fine.

(2) The movable unit 30 is moved in a specific direction with the arrangement position of one fixed unit 20 as a reference position, and the reception intensity level of the measurement original signal from the fixed unit 20 is set for each coordinate unit. Detected by the movable unit 30, the relationship between the reception intensity level and the distance from the reference position is obtained, and a graph is created, for example. The relationship between the reception intensity level and the distance is the reference information for the fixing device 20. Then, by performing the same operation as described above, the relationship between the reception intensity level and the distance for all the fixing devices 20 is obtained, so that the target reference information is obtained.

More specifically, for example, in the example of FIG. 1 in which the fixing devices 20A to 20D are arranged at each corner of the rectangular measurement target area P, as shown in FIG. The X axis is set in the horizontal direction of the rectangle, the Y axis is set in the vertical direction perpendicular to the X axis, and the measurement target area P
Are equally divided in the X-axis direction and the Y-axis direction to set square unit areas U, and position coordinates are set in each unit area U. The position coordinates can be set, for example, as addresses (X, Y) when the whole is regarded as a matrix. In the example of FIG. 4, the measurement target area P is divided into a unit area U of 5 rows and 6 columns, and accordingly, the fixing device 20A
The position coordinates of the unit area U to which the 20D belongs are (1, 1), (1, 6), (6, 6), and (6, 1).

Then, one of the fixing devices 20A to 20D
For example, only the fixing device 20A is operated and the other fixing devices are set in a non-operation state. In this state, all the unit areas U belonging to the first row extending in the X-axis direction, that is, the first column to the last column ( In all the unit areas U up to the sixth column in the example of FIG. 4, the reception intensity level at the central point G is detected, and the result is recorded in relation to the position coordinates. (Note that the recorded reception intensity level is simply referred to as “intensity level” in the reference information.)

By the above operation, the fixing units 20 for all the unit areas U belonging to the first row arranged in the X-axis direction are set.
Reference information related to A is obtained. Therefore, by performing the same operation for all rows, reference information on the fixing device 20A for the entire area of the measurement target area P can be obtained. Then, the same operation as described above is performed on all the other fixing devices, whereby reference information on all the fixing devices 20 is obtained.

The reference information obtained as described above is
The reference information is stored in the reference information storage unit 16 of the central control device 10, and this reference information is read out and referred to by the arithmetic processing unit 14 as necessary.

In the present invention, with the above configuration, the moving object M in the measurement target area P will be described as follows.
Are measured. First, a transmission command signal is issued from the central control device 10, whereby the fixing device 20A
20D generate measurement original signal pulses a to d in the state shown in FIG.

On the other hand, a trigger command signal is sent from the central control unit 10 to the controller 40 at the same time as the transmission command signal, and as shown in FIG. Is in the operating state, and the movable unit 30 detects the reception intensity level by each of the measurement original signal pulses a to d from each of the fixed units 20A to 20D. That is, in the movable unit 30,
The reception intensity levels of the measurement original signal pulses a to d from the four fixers 20A to 20D are detected in this order, and each of them is subjected to arithmetic processing according to a predetermined program.
Measurement data corresponding to the four detection results are collectively transmitted from the movable unit 30 as measurement data signals by radio waves. FIG. 5 is an explanatory graph showing a state of transmission and reception of each signal between the movable unit, the fixed unit, and the controller.

The measurement data signal based on the radio wave is received by the controller 40 and transmitted to the central control unit 10. The arithmetic processing unit 14 of the central control unit 10 stores the reference information stored in the reference information storage unit 16 in advance. Is contrasted with.
Then, in the reference information, the position coordinates of the unit area of the intensity level corresponding to the detected reception intensity level are determined, whereby the unit area where the moving object M is located can be obtained as the position coordinates. The above operation is performed during the pause period N between the pulse groups of the measurement original signal shown in FIG. Therefore, in effect, the current position of the moving object can be obtained in real time.

Thus, a certain one obtained as described above
Strictly speaking, the information on the two fixers 20 is
The distance information includes a factor relating to the distance to the movable unit 30 with the arrangement position of 0 as a reference position. Therefore, only a single distance information indicates a circle having a specific radius centered on the position of the fixed unit 20, for example. It is only possible to determine that the movable unit 30 exists on any of the circumferences, and it is not possible to specifically determine specific position coordinates.

However, when a plurality of fixing devices 20 are arranged at different positions and distance information can be obtained from them, a method of obtaining the intersection of circles intersecting each other by combining the plurality of distance information, for example, is used. Similarly, the position coordinates relating to the current position of the movable unit 30 can be obtained with high accuracy. For this reason, in the present invention, it is necessary that the number of the fixing devices 20 to be arranged in one measurement target region is two or more, preferably three or more, and more preferably four. Or more.

The reference information is obtained by dividing the entire surface of the measurement target area P into specific unit areas, and obtaining, for each unit area, the reception intensity level of the original signal for measurement from each fixing device. Therefore, the position coordinates of the moving object obtained by the present invention are based on the position coordinates set in the unit area.

In order to obtain the reference information, the measurement target area P is divided into unit areas each having a size corresponding to the target measurement accuracy, and a group of two or more unit areas (see FIG. 1) that are continuously arranged in one line. This is referred to as a “unit area series”.) For each unit area series, for each unit area belonging to the unit area series, the reception intensity level of the original signal for measurement by a specific fixed device is scanned and measured. An operation of acquiring series reference information is performed for some unit area series, and as a result, all unit areas are included in any one of the unit area series. The collection of the series reference information is the reference information on the specific fixing device for the measurement target area P. In the above, it is important that the unit area series to be measured is large, that is, the number of series reference information is large in order to obtain highly accurate reference information. Therefore, normally, a certain unit area belongs to a plurality of unit area series at the same time.

The one series reference information obtained as described above is not a mere set of reception intensity level information of each unit area belonging to the corresponding unit area series, but a continuous set of unit area continuous in a specific state. Because the information is information, the positional relationship between a certain unit area and unit areas that are continuous before and after the unit area is also an element of the information.

More specifically, for example, the measurement target area P is divided into a matrix of unit areas arranged vertically and horizontally, and each row and each column is defined as a unit area series, and the movable unit is moved along the unit area series. Then, when the reception intensity level is scanned and measured for every unit area belonging to the row or column, series reference information is obtained. Then, if the series reference information for all the rows and columns is obtained, the reference information can be obtained as an aggregate thereof.

FIG. 6 shows series reference information (curve A) relating to the fixing device A and series reference information (curve B) relating to the fixing device B obtained for a certain unit region series in a certain measurement target region. It is a curve figure. In this figure, the horizontal axis is the position coordinate number, that is, the column number, and the vertical axis is the intensity level, which is a relative unit.

In this example, one row (this is referred to as an m-th row) in the case where a measurement target area is divided into a matrix of 15 rows and 19 columns is defined as a unit area series. , A total of 19 unit regions belonging to the fixed unit A are measured by scanning from the unit region in the first column to the nineteenth column in order, and the measurement values are connected in the order of the unit regions arranged continuously. , And a graph (curve B) of series reference information related to the fixing device B according to the present invention.

As is apparent from this figure, the reception intensity level actually obtained for a certain unit area series is such that the position of the unit area series is fixed with respect to the arrangement position (reference position) of the fixing device. Nevertheless, that is, the measurement positions of the 19 unit areas belonging to the m-th row and arranged in the X-axis direction are completely irregular despite having a specific regular distance relationship with the reference position. It has a vibrating profile.

However, when the moving object is present in any of the m-th rows, the reception intensity level of the original signal pulse for measurement by the fixed device A detected by the movable device is "200".
When this reception intensity level is compared with the series reference information of FIG. 6, in the series reference information, the place where the intensity level is “200” is only one point in the fifth column, and It is detected that the movable unit exists at the position coordinates (m, 5). The actual control detection operation of detecting or measuring the position coordinates of the corresponding location by comparing the information of the reception intensity level with the reference information is performed by the arithmetic processing in the arithmetic processing unit 14 of the central control device 10 and the obtained position is determined. The coordinates (m, 5) are output as a measurement signal. At this time, if it is confirmed at the same time that the reception intensity level of the original signal pulse for measurement by the fixed device B is "about 510", it is more certain that the movable device exists in the fifth row, and the measurement accuracy is high. It will be.

As described above, by comparing the reception intensity level of the measurement original signal of the specific fixed device obtained in the movable device with the reference information of the specific fixed device, which is obtained in advance, the relevant information is obtained. Distance information of the movable unit to the specific fixed unit is obtained. Then, as described above, by processing the distance information of the two or more fixed devices arranged at different positions in combination, the position where the movable device actually exists, that is, the position coordinates of the moving body is specifically determined. And specifically.

In a certain series of reference information, if there is only one location of the intensity level corresponding to the reception intensity level as described above, it is clear that the location is the target location from which the position coordinates should be obtained. Usually, a plurality of locations of the same intensity level exist in one series reference information. For example, in the curve A according to the fixing device A in FIG. 6, the location of the intensity level corresponding to the reception intensity level “330” exists at two locations in the fourth and seventh columns. In such a case, it is difficult to determine which location is the target location only from the information on the reception intensity level.

Therefore, in the present invention, when two or more locations of the same intensity level exist in one obtained series reference information, the area of the unit area series related to the series reference information is divided into a plurality of areas. So that no one divided area includes two or more locations of the same intensity level. That is, in the curve of the series reference information, an area in which the intensity level increases or decreases in one direction is defined as one divided area. Therefore, the position of the upwardly convex or downwardly convex vertex in the curve of the series reference information (or the position where the sign of the first derivative changes) may be divided as a dividing line.

For example, in the example of FIG. 6, the curve A has a fifth column, a ninth column,
The positions of the 0th column, the 11th column, the 12th column, the 14th column, and the 17th column are the positions of the dividing lines. On the other hand, regarding the curve B, the positions of the eighth, tenth, eleventh, twelfth, fourteenth, and fifteenth columns are set as the positions of the dividing lines.

In one of the division areas of the series reference information, there is only one location having the same intensity level and there are no more than two locations. By comparing with the series reference information in the area, the target location can be reliably determined.

In the above case, there are a plurality of division areas each including only one location of the intensity level corresponding to the reception intensity level, and each of these division areas is a candidate division having a possibility that a target location exists. Since it is an area, it is necessary to select one of them as a control divided area. The following method can be used to select the division for comparison.

(1) Method of Considering Position Coordinates by Previous Measurement Operation The position coordinate measurement operation according to the present invention is actually performed at a rate of, for example, 20 to 50 times per second in accordance with the frequency of sending a trigger signal. Repeated. Therefore, when there are a plurality of candidate divided areas in one measurement operation, the position coordinates detected in the previous measurement operation belong to all candidate divided areas in consideration of the previous measurement result. Subdivision,
Alternatively, the closest divided area is selected as a control divided area. This is because the actual movement of the moving object is analogous due to continuous position changes, and it takes only a few milliseconds from the time of the last measurement operation to the time of this measurement operation. This is because it is impossible to move to the position coordinates greatly separated from the previous position coordinates, and therefore, the above-mentioned divided area is a control divided area with almost no exception.

(2) Method for Considering the Relationship between Reception Intensity Levels by Different Fixtures in the Previous Measurement Operation For the same reason as described in the above (1), in the previous measurement operation, the position coordinates detected at the detected position coordinates are used. The magnitude relationship between the intensity level of the fixing device A and the intensity level of the fixing device B, and the magnitude of the difference between the intensity levels are obtained as information. Therefore, using these pieces of information between intensity levels, a divided area having the same or closest intensity level relationship or a divided area having the same or closest intensity level difference state is selected as a control divided area. . Alternatively, it is also possible to further select the control division area in consideration of the fact that the tendency when the difference between the intensity levels changes is the same or similar.

In the present invention, appropriate correction processing can be added to the reference information acquired in advance so as to be suitable for the actual comparison processing. One example of a correction process that is practically the most effective is a linearization correction process in which a change in the intensity level is regarded as a linear change for each divided area in the series reference information. Specifically, the curve A in FIG. 6 can be corrected by replacing a curve for each divided area, for example, a curve from the first column to the fifth column with one straight line segment. A straight line segment S directly connecting the coordinates in the first column and the coordinates in the fifth column is obtained.

According to such a linearization correction process, the line representing the intensity level in the divided area is not a curve but an extremely simple y = ax + b that is established in common in all the unit areas related to the divided area. Since it can be expressed by a logical expression based on a simple linear expression, the logical expression for the arithmetic processing in the arithmetic processing unit of the central control unit becomes very simple, and therefore, the processing program becomes simple, and The detection processing time can be greatly reduced, which is extremely advantageous.

In the present invention, the radio wave of the original signal pulse for measurement preferably has substantially the same frequency and output level for each fixing device, and thus has substantially the same frequency and output level. In such a case, the range of radio waves to be received and processed by the movable unit is narrow in terms of frequency and output level, so that the performance of the movable unit may be simple, and after all, the configuration is simple. It can be. In addition, the radio wave related to the measurement original signal preferably has a frequency of 150 MHz or less. In this case, there is practically no risk of reflection or interference, so that it is possible to measure position coordinates with high accuracy. Become.

Further, when the pulse waveform of the measurement original signal from each fixing device has a high-level portion H having a high intensity level and a low-level portion L having a low intensity level as shown in FIG. By detecting the difference between the two, stable detection can be performed. That is, for example, according to a simple rectangular pulse, if the power supply voltage of the movable unit 30 is reduced or the determination circuit is deteriorated, this directly causes an error in the reception intensity level. However, if a difference between the power levels of the high-level portion H and the low-level portion L is received as the reception power level, a stable reception result is always obtained.

In the present invention, the movable unit is not particularly limited. However, in the case where an individual serving as a moving body is changed from time to time, the movable unit is portable.
In this case, the movable unit may be provided with a band or other holding unit for convenience of holding by the moving body, or a pin or a clip for fastening the movable unit to a part of the costume. It is preferable to provide them. Further, it is preferable to use a small battery as a driving power source.

On the other hand, when the individual to be a moving object is a thing that is unlikely to be changed, for example, an automatic traveling robot, a portable movable device may be held.
It is also possible to attach a movable unit to a part of the moving body itself. In this case, not a small battery but a storage battery can be suitably used as the driving power source.

The measurement target area to which the method of the present invention is applied is not particularly limited, and a relatively short distance area where the position of a movable body capable of holding the movable unit should be detected in real time is measured. It can be an area.
Specifically, for example, an indoor space in a building, an indoor space such as a theater stage, an outdoor space such as a rooftop, an outdoor theater, or a limited relatively small area can be set as the measurement target area. However, it may be practically difficult to obtain reference information if a very large area is to be measured. From such a viewpoint, the measurement target region in the present invention has a longest distance of, for example, 1 km or less, particularly 100 m.
It is particularly useful in the following areas:

Although the present invention has been described in detail, various changes can be made in the present invention. For example, it is possible to simultaneously measure the position coordinates of a plurality of moving objects. In this case, it is necessary to be able to individually control the movable units held by each of the plurality of moving objects. For this purpose, for example, the frequency of the measurement original signal received by each movable unit is different. Means, a means for giving a time difference to the original signal for measurement received by each movable unit, and others can be used.If there is no particular problem, a central control unit, a fixed unit and a controller can be commonly used. it can. In the above description, the “pulse” is not particularly limited in its waveform, and may be any pulse that can be processed as a pulse signal. Therefore, a so-called triangular wave, sawtooth wave, trapezoidal wave, a composite wave of these waveform components, or another waveform may be used instead of a rectangular wave pulse or a pulse consisting of only a rectangular wave component.

[0069]

According to the method and apparatus for measuring the position coordinates of a moving object of the present invention, an original signal for measurement by radio waves emitted from a fixed device is received by a moving device held by the moving object, and the reception intensity level at this time is received. The central controller fixes the movable unit by comparing it with the reference information previously obtained, which contains the relationship between the distance and the intensity level with the position where the fixed unit is located as the reference position. Distance information from the vessel can be obtained. As a result, distance information to the position of the movable unit can be obtained from the position of the fixed unit as a reference position.By performing the arithmetic processing by combining the distance information from the plurality of fixed units provided at different positions, The position coordinates of the movable unit, that is, the position coordinates of the moving body can be obtained. Moreover, since the transmission and reception of signals are performed by radio waves or electrical communication, the position coordinates of the moving object can be obtained in real time.

By forming the reference information as an aggregate of series reference information relating to one fixing device, arithmetic processing for comparison becomes easy, and the intensity level is included in one series reference information. Even when there are a plurality of the same places, the area can be divided into a plurality of divided areas so that no two or more places of the same intensity level exist in one divided area. In addition, the position coordinates of the moving object can be measured with high accuracy.

Since the measurement operation for obtaining the position coordinates of the moving object in the measurement target area is usually performed repeatedly, a plurality of candidate division areas having the same intensity level in one series reference information can be obtained. From among them, the method of selecting the divided area containing the position coordinates obtained by the previous measurement operation or the divided area closest to this as the control divided area, or the position coordinates obtained by the previous measurement operation By using a method of selecting a divisional area having the same or the closest relation to the magnitude relation of the reception intensity levels of the different fixed devices as the reference divisional area, the position coordinates of the target location can be obtained very reliably and rationally. be able to.

In the position coordinate measuring apparatus for a moving object according to the present invention, since the frequency and the output level of the radio wave relating to the original signal for measurement from each fixed unit are substantially the same, the movable unit should correspond. The range of the radio wave is narrowed, and as a result, the configuration of the movable unit can be simplified.

If the original signal for measurement from the fixing device is a radio wave having a frequency of 150 MHz or less, there is practically no risk of reflection or interference, and the position coordinates can be measured with high accuracy. It becomes possible. Furthermore, if the original signal for measurement from each fixer is pulse-shaped and one pulse has a high-level portion with a high intensity level and a low-level portion with a low intensity level, the change in environmental conditions will Even if there is, it is possible to stably detect the reception intensity level.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram schematically showing an example of a configuration of a position coordinate measuring device for a moving object according to the present invention.

FIG. 2 is a block diagram schematically showing major functional parts constituting the position coordinate measuring apparatus for a moving object according to the present invention, and schematically showing a state of connection between them.

FIG. 3 is a curve diagram showing a temporal state of a pulse of a measurement original signal of each of the fixing devices 20A to 20D.
(D) shows the original measurement signal pulses a to d from the fixers 20A to 20D, respectively, and (e) shows the explanatory curves obtained by superimposing the curves (a) to (d) on a common time axis. FIG.

FIG. 4 is an explanatory diagram of acquiring reference information according to the present invention.

FIG. 5 is an explanatory graph showing a state of transmission and reception of each signal between a movable unit, a fixed unit, and a controller.

FIG. 6 is a curve diagram showing series reference information (curve A) relating to the fixing device A and series reference information (curve B) relating to the fixing device B obtained for a certain unit region series in a certain measurement target region. is there.

FIG. 7 is an explanatory diagram showing a modified example of the pulse waveform of the measurement original signal.

[Explanation of symbols]

 P Measurement target area 20, 20A to 20D Fixed device 10 Central control device a to d Original signal pulse for measurement M Moving object 30 Movable device N Pause period 40 Controller 12 Drive control unit 14 Operation processing unit 16 Reference information storage unit U unit Area G Central part H High level part L Low level part

Continuing from the front page (72) Inventor Akihisa Sakata 1-4505 Aobudai, Zama-shi, Kanagawa Wakabayashi Building F-term in Emile Electronics Development Building (reference) 3F059 BB04 DA08 DD00 GA00 3F060 CA11 5H301 AA02 AA10 BB14 EE31 FF11 FF25 GG07 KK08 KK18 5J062 BB01 BB05 CC14

Claims (10)

[Claims] 1. A method for measuring the position coordinates of a moving object moving in a specific measurement target area in the measurement target area, wherein each of the plurality of fixed points emits a measurement original signal by radio waves to the measurement target area. A movable unit that receives the original signal for measurement, calculates the reception intensity level of the received original signal for measurement, and emits the result as a measurement data signal by radio waves, And a central controller for receiving the measurement data signal from the movable unit. In the central controller, the reception intensity level at the movable unit obtained from the measurement data signal is determined in advance for the corresponding fixed unit. The position of the moving object in the measurement target area is compared with the reference information containing the relationship between the distance with the arrangement position as the reference position and the reception intensity level. Position coordinate measurement method for a mobile body and performing a computation process for obtaining the. 2. The reference information corresponds to an individual fixing device. The reference information on each fixing device divides a measurement target region into a number of unit regions and continuously arranges two or more unit regions in one line. The group of unit areas is referred to as a unit area series, and for each unit area belonging to this unit area series, the operation of measuring the reception intensity level of the original signal for measurement by the fixing device and obtaining the series reference information is performed for different unit area series. 2. An aggregate of series reference information on a plurality of unit area series obtained by performing the operation.
4. The method for measuring position coordinates of a moving object according to item 1. 3. The series reference information is divided into a plurality of divided sections so that the area does not have a plurality of portions of the same intensity level in one divided section. A divided area including a location of the corresponding intensity level is selected as a control divided area, and in this comparative divided area, a calculation process for calculating the position coordinates of the location of the intensity level corresponding to the reception intensity level is performed. 3. The method for measuring position coordinates of a moving body according to claim 2, wherein 4. The method according to claim 3, wherein in the series reference information, a curve representing an intensity level is subjected to linearization correction processing in units of the divided area. 5. A method for automatically measuring the position coordinates of a moving object in which a measuring operation for obtaining the position coordinates of a moving object in a measurement target area is repeatedly performed, wherein a plurality of points having the same intensity level exist in one series reference information. 4. The divisional section including the position coordinates obtained by the previous measurement operation or the divisional area closest to the divisional division is selected as the control divisional section among the candidate divisional sections of (1) and (2). 4. The method for measuring position coordinates of a moving object according to 4. 6. A method for automatically measuring the position coordinates of a moving body in which a measurement operation for obtaining the position coordinates of a moving body in a measurement target area is repeatedly performed, wherein a plurality of locations having the same intensity level exist in one series reference information. Among the candidate sub-areas, the sub-area having the same or the closest relation to the magnitude relation of the intensity levels of the different fixing devices for the position coordinates obtained by the previous measurement operation is selected as the control sub-area. The method according to claim 3, wherein the position coordinates of the moving object are measured. 7. An apparatus for measuring the position coordinates of a moving object moving within a specific measurement target area in the measurement target area, each of which emits an original signal for measurement by radio waves to the measurement target area. A plurality of fixing devices fixedly arranged at different positions, receiving the measurement original signal, calculating the reception intensity level of the received measurement original signal, and emitting the result as a measurement data signal by radio wave, A movable unit held by the movable body; and a central control unit for receiving a measurement data signal from the movable unit. In the central control unit, a reception intensity level of the movable unit obtained from the measurement data signal is obtained in advance. By comparing with the reference information, which contains the relationship between the distance and the intensity level with the arrangement position of the corresponding fixing device as a reference position, the measurement object of the moving object is used. Position coordinate measurement device of the moving object, wherein the arithmetic processing to obtain the position coordinates in the region are carried out. 8. The apparatus according to claim 7, wherein the measurement original signal from each fixing device is based on radio waves having substantially the same frequency and output level. 9. The apparatus according to claim 7, wherein the original signal for measurement from each fixing device is a radio wave having a frequency of 150 MHz or less. 10. An original signal for measurement from each fixing device is pulse-shaped, and one pulse waveform has a high-level portion having a high intensity level and a low-level portion having a low intensity level. The position coordinate measuring device for a moving object according to claim 7.