CN106646380B  Multibasestation space positioning method and system  Google Patents
Multibasestation space positioning method and system Download PDFInfo
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 CN106646380B CN106646380B CN201611235546.0A CN201611235546A CN106646380B CN 106646380 B CN106646380 B CN 106646380B CN 201611235546 A CN201611235546 A CN 201611235546A CN 106646380 B CN106646380 B CN 106646380B
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Classifications

 G—PHYSICS
 G01—MEASURING; TESTING
 G01S—RADIO DIRECTIONFINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCEDETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
 G01S5/00—Positionfixing by coordinating two or more direction or position line determinations; Positionfixing by coordinating two or more distance determinations
 G01S5/18—Positionfixing by coordinating two or more direction or position line determinations; Positionfixing by coordinating two or more distance determinations using ultrasonic, sonic, or infrasonic waves
 G01S5/26—Position of receiver fixed by coordinating a plurality of position lines defined by pathdifference measurements
Abstract
Description
Technical Field
The invention relates to the technical field of space positioning, in particular to a method and a system for multibasestation space positioning.
Background
With the development and popularization of information technology and wireless communication technology, people increasingly demand positioning and navigation. The Global Positioning System (GPS) is the most widely applied positioning technology at present, and can meet the outdoor positioning requirement of people. However, when the GPS receiver is operated indoors, the signal strength is greatly reduced by the influence of buildings, and the receiver cannot perform positioning.
In order to realize indoor positioning, the related schemes perform positioning sensing through technologies such as an indoor Global Positioning System (GPS), infrared, bluetooth positioning, WIFI positioning, RFID (Radio frequency identification) positioning, and binocular positioning. However, the related indoor positioning schemes have high cost, complex equipment configuration and insufficient positioning accuracy, and cannot meet the requirements of people in the aspects of virtual reality interaction, augmented reality interaction, indoor robot navigation and the like. And in some large space ranges, positioning is particularly difficult, especially for multiple targets.
Disclosure of Invention
The invention provides a multibasestation space positioning method and a system for solving the problems, and achieves the purpose of being applied to a plurality of targets and a large range by networking positioning base stations in space.
According to an aspect of the present invention, there is provided a method for spatial positioning of multiple base stations, comprising the following steps:
s1, respectively measuring the relative positions of every two base stations in the space;
s2, establishing a space coordinate system to obtain the coordinates of each base station in the space coordinate system;
s3, obtaining the coordinate of the equipment to be positioned in any base station coordinate system in the space and the absolute coordinate in the space coordinate system according to the coordinate of the equipment to be positioned in a certain base station coordinate system in the space.
Preferably, the step S1 specifically includes:
s11, respectively measuring the coordinates of the same device to be positioned in the coordinate systems of the two adjacent base stations;
s12, obtaining the transformation relation between one base station coordinate system and the other base station coordinate system through coordinate transformation;
and S13, repeating the steps S11 to S12 to obtain the relative position of every two adjacent coordinate systems in the space.
Preferably, the directions of the axes of the base station coordinate systems corresponding to the plurality of positioning base stations in the space are the same, and the relative positions of every two base station coordinate systems in the space are obtained through translation calculation.
Preferably, when the coordinate systems of the base stations in the space have an inclination angle with each other, the coordinates of the device to be positioned in the space coordinate system in the two base stations are (x1, y1, z1) and (x2, y2, z2), respectively, and the inclination angles of the two base stations with respect to the geodetic coordinate system are (α)_{1}，β_{1}，γ_{1}) And (α)_{2}，β_{2}，γ_{2}) Then, the rotation angle (α, γ) of one base station relative to the other base station can be obtained as (α)_{2}α_{1},β_{2}β_{1},γ_{2}γ_{1}) Then the coordinates (x0, y0, z0) of one base station relative to another base station can be obtained by:
(x_{0},y_{0},z_{0})^{T}＝(x_{1},y_{1},z_{1})^{T}R(α，β，γ)*(x_{2},y_{2},z_{2})^{T}
preferably, the method for measuring the coordinates of the same device to be positioned in two adjacent base station coordinate systems specifically includes:
measuring the distance from the point to be measured to the coordinate origin of the coordinate system of the base station by an ultrasonic ranging method;
respectively measuring the included angle between the point to be measured and the plane formed by the vertical lines of two coordinate axes in the coordinate system of the base station and the two coordinate axes by a rotating plane laser scanning angle measuring method;
and calculating to obtain the coordinates of the point to be measured in the coordinate system of the base station.
Preferably, in step S2, a spatial coordinate system is established with one of the base stations in space as a coordinate origin, and the spatial coordinate system coincides with the coordinate system of the base station.
A multibasestation space positioning system comprises at least two positioning base stations used for sending positioning signals and at least one tobepositioned device used for receiving the positioning signals, wherein each positioning base station is provided with a base station coordinate system, a space coordinate system is arranged in the space, and signal coverage areas of the at least two positioning base stations in the space are mutually overlapped and are not completely overlapped.
Preferably, the two positioning base stations are respectively located in front of and behind the space, the positioning signals are relatively transmitted, and the signal coverage spaces are mutually overlapped and not completely overlapped.
Preferably, the number of the positioning base stations is three, and two of the three positioning base stations are located behind the space and one is located in front of the space, or two of the three positioning base stations are located in front of the space and one is located behind the space; and the positioning signals of the three base stations are relatively transmitted, and the signal coverage areas are mutually overlapped and not completely overlapped.
Preferably, one of the at least two positioning base stations is a master base station, the other positioning base stations are slave base stations, and a base station coordinate system of the master base station is used as a spatial coordinate system.
The application provides a multibasestation space positioning method, which comprises the steps of establishing a base station coordinate system for each base station in a space, establishing a space coordinate system for the whole space, and obtaining the coordinate of any point in one base station in any other base station coordinate system and the absolute coordinate in the space coordinate system through the calculated relative position between the base stations in the space, so that the accurate positioning in a large space can be realized.
Drawings
FIG. 1 is a flow chart of a method of an embodiment of the present invention;
FIG. 2 is a schematic diagram of a method for measuring an angle by laser scanning a rotating plane according to an embodiment of the present invention;
FIG. 3 is a block diagram showing the system configuration in embodiment 2 of the present invention;
fig. 4 is a block diagram of the system configuration of embodiment 3 of the present invention.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Example 1
Fig. 1 shows a multibase station spatial positioning method, which comprises the following steps:
and S1, respectively measuring the relative positions of every two base stations in the space.
Each base station is provided with an independent identification code ID, and the base stations are identified and distinguished through the identification code IDs; the identification code can be the transmitted ultrasonic wave, sound wave, infrared light, visible light, frequency and other marks with different frequencies, and can also be a code word setting for modulating the identification code. The action range of each base station can be a regular sphere or a sector, or an irregular shape, and the action ranges of every two adjacent base stations are overlapped;
the testing method is various, and two testing methods are specifically described in this embodiment.
The first test method comprises the following steps: when the directions of the coordinate systems of the base stations are different, the base stations can know the positions and the inclination angles of the base stations in the space by sending signals to each other. The specific process is as follows:
each base station comprises a positioning signal receiving unit, and the coordinates of the base station relative to other base stations are calculated by receiving positioning signals sent by other base stations.
Each base station includes an inclination measuring unit that measures its own inclination relative to the geodetic coordinate system.
When coordinate systems of the base stations in the space have inclination angles with each other, coordinates of the equipment to be positioned in the space coordinate system in the two base stations are respectively (x1, y1, z1) and (x2, y2, z2), and inclination angles of the two base stations relative to the geodetic coordinate system are respectively (α)_{1}，β_{1}，γ_{1}) And (α)_{2}，β_{2}，γ_{2}) Then, the rotation angle (α, γ) of one base station relative to the other base station can be obtained as (α)_{2}α_{1},β_{2}β_{1},γ_{2}γ_{1}) Then the coordinates (x0, y0, z0) of one base station relative to another base station can be obtained by:
(x_{0},y_{0},z_{0})^{T}＝(x_{1},y_{1},z_{1})^{T}R(α，β，γ)*(x_{2},y_{2},z_{2})^{T}
by using the method, the position relation of every two adjacent base stations can be obtained.
The second test method comprises the following steps: and when the directions of the coordinate systems of the base stations are the same, the positions of the two adjacent base stations are deduced through the coordinates of the equipment to be positioned at each two adjacent base stations.
The method specifically comprises the following steps:
s11, respectively measuring the coordinates of the same device to be positioned in the coordinate systems of the two adjacent base stations;
s12, obtaining the transformation relation from the coordinate of any point in one base station coordinate system to the coordinate system of another base station through coordinate transformation;
s13, the positions of the points to be measured move in the space, and the steps S11 to S12 are repeated to obtain the relative positions of every two adjacent coordinate systems in the space.
And obtaining the relative position relation of the first base station and the second base station according to the coordinates (x1, y1, z1), (x2, y2 and z2) of the same device to be positioned relative to the two base stations. Because the directions of the coordinate systems of the base stations are uniformly arranged, and the coordinate systems of the base stations are in a translation relation, the coordinate position of the P2 base station relative to the coordinate position of the P1 base station is obtained through translation calculation and is as follows: (x1x2, y1y2, z1z 2).
The measurement of the coordinates of the equipment to be positioned in the two test modes can be realized in an optical and ultrasonic mode, or in alloptical signal measurement, ultrasonic measurement or wireless signal measurement and other modes;
in this embodiment, the coordinates of the device to be positioned in the first base station coordinate system are measured by using both optical and ultrasonic waves, and the step S11 specifically includes:
measuring the distance from the equipment to be positioned to the coordinate origin of a P1 coordinate system of the first base station by an ultrasonic ranging method;
measuring the space angle of the equipment to be positioned relative to a P1 coordinate system of the first base station by a rotating plane laser scanning angle measuring method;
and calculating the coordinates of the point to be measured in the first base station coordinate system through the space angle of the equipment to be positioned in the first base station P1 coordinate system and the distance from the point to the coordinate origin of the first base station P1 coordinate system.
In this embodiment, as shown in fig. 2, the method for measuring the angle by scanning the laser with the rotating plane includes:
arranging a first rotating laser plane rotating around an x axis of a base station coordinate system and a second rotating laser plane rotating around a y axis on a base station, and arranging equipment to be positioned on equipment A to be positioned; synchronizing the reference time of the equipment to be positioned and the base station;
the first rotating laser plane rotates around the x axis at a first reference time t 1' to send a first laser plane signal; the second rotating laser plane rotates around the y axis at a second reference time t 2' to send a second laser plane signal;
detecting a first laser plane signal and a second laser plane signal by the equipment to be positioned, and respectively recording a first time t1 when the first laser plane signal is received and a second time t2 when the second laser plane signal is received;
the method comprises the steps of obtaining a rotation angle α ═ (t1t1 ')/w 1 of a first rotating laser plane according to a rotation speed w1 of the first rotating laser plane and a time difference t1t 1' between the first moment and the first reference moment, obtaining a rotation angle β ═ (t2t2 ')/w 2 of a second rotating laser plane according to a rotation speed w2 of the second rotating laser plane and a time difference t2t 2' between the second moment and the second reference moment, wherein the rotation angle of the first rotating laser plane is an included angle between a vertical line from a point A to an x axis to be measured and a xoy plane, and the rotation angle of the first rotating laser plane is an included angle β between a vertical line from the point A to a y axis to the xoy plane to be positioned.
The coordinates (x1, y1, z1) of the device to be positioned relative to the first base station P1 are obtained according to the following calculation method:
x_{1}tanβ＝y_{1}tanα＝z_{1}
x_{1} ^{2}+y_{1} ^{2}+z_{1} ^{2}＝L^{2}
wherein, (x1, y1, z1) is the coordinate of the equipment A to be positioned in the first base station coordinate system, and L is the distance from the equipment to be positioned to the coordinate origin of the base station coordinate system; and solving the upper program group to obtain the coordinate value of the equipment A to be positioned in the corresponding base station coordinate system.
Similarly, the coordinates (x2, y2, z2) of the device to be positioned relative to the adjacent second base station P2 are calculated.
And S2, establishing a space coordinate system, and obtaining the coordinates of each base station in the space coordinate system.
Specifically, in this embodiment, the plurality of base stations can be divided into a master base station and a plurality of slave base stations, and the coordinate system of the master base station is used as a spatial coordinate system, and the positions of the other slave base stations in the spatial coordinate system are obtained according to the coordinate relationship between every two base stations obtained in step S1.
If the position of each slave base station relative to the master base station can be directly obtained through the step of S1, the coordinates of each slave base station in the space coordinate system are directly obtained; if the position of each slave base station relative to the master base station cannot be directly obtained through the step S1, for example, if only the coordinate position of the P2 base station relative to the P1 base station and the coordinate position of the third base station P3 relative to the P2 base station are obtained by taking the P1 as the master base station and the P2 and the P3 as the slave base stations, then the coordinate position of the P3 base station relative to the P1 base station can be obtained by further converting the coordinate positions of the P2 base station relative to the P1 base station and the third base station P3 relative to the P2 base station. By analogy, the coordinates of each slave base station in the spatial coordinate system with respect to the master base station can be obtained.
And S3, obtaining the coordinate of the target in any base station coordinate system in the space and the absolute coordinate in the space coordinate system according to the coordinate of the target in a certain base station coordinate system in the space.
For the case where the coordinate systems of the base stations in space have a mutual inclination, the position of the device to be positioned in the large space can be determined by the following method.
If it has coordinates (x) relative to the slave base station P2_{2},y_{2},z_{2}) The coordinates of the base station P2 with respect to the base station P1 are (x0, y0, z0), and the inclinations of the base stations P1 and P2 with respect to the geodetic coordinate system are (α)_{1}，β_{1}，γ_{1}) And (α)_{2}，β_{2}，γ_{2}) The rotation angle (α, γ) of the base station P2 with respect to the base station P1 is (α)_{2}α_{1}，β_{2}β_{1}，γ_{2}γ_{1}) The coordinates (x) of the device to be positioned relative to the main base station P1_{1},y_{1},z_{1}) Can be obtained by the following formula:
(x_{1},y_{1},z_{1})^{T}＝R(α，β，γ)*(x_{2},y_{2},z_{2})^{T}+(x_{0},y_{0},z_{0})^{T}
wherein:
and for the condition that the directions of coordinate systems of all base stations in the space are uniform, the coordinate conversion and the positioning are quicker. Specifically, if the coordinates of the device to be positioned in the coordinate system of the slave base station P2 are (xA, yA, zA), then: the coordinates of the equipment to be positioned in the main base station P1 coordinate system are as follows: (xA + x1x2, yA + y1y2, zA + z1z 2). Therefore, the coordinates of the equipment to be positioned relative to any slave base station can be converted into the coordinates relative to the master base station P1, and the positioning in a large space is realized.
In the using process, the position of the equipment to be positioned in any base station and the position of the equipment to be positioned in the whole space coordinate system can be obtained by the mutual positions of all the base stations and the position of the equipment to be positioned in one of the base stations, so that the space positioning is expanded, and the uniform positioning of a plurality of targets in a large space is realized.
In this implementation, the system may further include a plurality of devices to be positioned, and the positioning in the large space with the base station P1 as the master base station and the base stations P2, P3 and the like as the slave base stations can be realized by the above method, and the positioning information of each device to be positioned in the large space is transmitted to the terminal, for example, in a VR game, so that the multiperson large space interactive game can be realized.
Example 2
Fig. 3 shows a multibase station spatial positioning system of the present invention, comprising: the positioning system comprises at least two positioning base stations in a space coordinate system and at least one device to be positioned; the positioning base station is used for sending positioning signals, and signal coverage areas of the positioning base stations in space are mutually overlapped and not completely overlapped; the device to be positioned is configured to receive the positioning signal sent by the at least 1 positioning base station, and perform spatial positioning according to the method in embodiment 1.
Specifically, as shown in fig. 3, there is a positioning base station in front of and behind the space, each positioning base station has a base station coordinate system, and the positioning base station transmits positioning signals, such as ultrasonic signals and laser signals, into the space. Assuming that the positioning base station located in front is the main base station, the main base station transmits a positioning signal within a range of about 120 degrees to the rear of the space by using the coordinate system of the positioning base station located in front as a space coordinate system. The positioning base station positioned at the rear part transmits a positioning signal within a range of about 120 degrees to the front space from the base station, and the signals of the front and rear positioning base stations are overlapped but not completely overlapped. The device to be positioned is located in the space, and the positions of the master base station and the slave base station can be determined by using the positioning method of the first embodiment. When the equipment to be positioned is positioned in the signal coverage area of the main base station, the position of the equipment to be positioned in the base station coordinate system of the main base station and the position of the equipment to be positioned in the space coordinate system can be directly obtained; when the position to be located is in the signal coverage area of the slave base station, the position of the slave base station in the coordinate system of the slave base station can be obtained and converted into the coordinate position in the coordinate system relative to the master base station, namely the space coordinate system.
Example 3
As shown in fig. 4, there is a positioning base station in front of the space and two positioning base stations in back, each having a base station coordinate system, and the three base stations transmit positioning signals, such as ultrasonic signals and laser signals, to the inside of the space. Assuming that the positioning base station located in front is a master base station, the coordinate system of the positioning base station located in front is used as a space coordinate system to transmit the positioning signal within about 120 degrees to the rear of the space, two positioning base stations located in rear are slave base stations and are placed at a certain inclination angle to transmit the positioning signal within about 120 degrees to the front of the space, and the signals of the three positioning base stations are overlapped but not completely overlapped. The device to be positioned is located in the space, and the positions of the master base station and the slave base station can be determined by using the positioning method of the first embodiment. When the equipment to be positioned is positioned in the signal coverage area of the main base station, the position of the equipment to be positioned in the base station coordinate system of the main base station and the position of the equipment to be positioned in the space coordinate system can be directly obtained; when the position to be located is in the signal coverage area of the slave base station, the coordinate position of the slave base station relative to the signal coverage area can be obtained and converted into a coordinate system relative to the master base station, namely the coordinate position in a space coordinate system.
The above embodiments 2 and 3 are only for explaining the technical solution of the present invention, and do not limit the present invention, and in the specific implementation, there may be 4 positioning base stations, 5 positioning base stations, etc., the placement positions of the positioning base stations in the space may be in other manners, and the setting of the master base station and the slave base station may be in other manners as long as the intention of the invention can be achieved.
The method comprises the steps of establishing a base station coordinate system for each base station in a space, establishing a space coordinate system for the whole space, and obtaining the coordinate of any point in one base station in any other base station coordinate system and the absolute coordinate in the space coordinate system through the calculated relative position between the base stations in the space.
The multibasestation space positioning system provided by the application has the advantages that the moving range of the equipment to be positioned is larger through the arrangement of the multiple base stations, and the problem that the positioning signal cannot be obtained once the equipment to be positioned is turned or an obstacle exists due to the fact that part of the equipment to be positioned can only face the base station when being used is solved. The multibasestation space positioning system can also be used for multitarget positioning, and after the absolute coordinates of each tobepositioned device are obtained, the absolute coordinates are transmitted to external devices, such as VR devices and unmanned aerial vehicle devices, so that the multitarget positioning in large space can be obtained.
Finally, the method of the present application is only a preferred embodiment and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
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