JP7329652B1 - Positioning device - Google Patents

Abstract

A positioning device that suppresses errors in positioning when radio waves from one base station can be received is provided. A radio positioning device (1) that receives radio signals from one or more base stations and outputs, for each base station, radio positioning distance, which is the distance from the base station to a vehicle, and base station position information. , an autonomous positioning device 2 that outputs the vehicle position detected by autonomous navigation as an autonomous positioning position, and an autonomous positioning distance, which is the distance from the base station to the autonomous positioning position, for each base station. Only when the autonomous positioning distance is greater than the radio positioning distance, the base station whose autonomous positioning distance is greater than the radio positioning distance is the selected base station, the radio positioning distance of the selected base station is the selected radio positioning distance, and the radio positioning distance from the selected base station is It is characterized by comprising a positioning position calculation unit 3 that outputs the position of the selected radio positioning distance in the direction of the autonomous positioning position as the positioning position. [Selection drawing] Fig. 1

Description

The present application relates to a positioning device.

In a vehicle control system that controls a vehicle to travel along a designated travel route, the position of the vehicle to be controlled is measured and the vehicle is controlled to travel within a designated range with respect to the travel route. Positioning of a vehicle requires the distance from the satellite to the vehicle calculated from the propagation time, which is the time it takes for radio waves transmitted from multiple satellites with known positions to be received by the receiver installed in the vehicle. Positioning by GNSS (Global Navigation Satellite System) used, or distance obtained from the propagation time of ultra-short pulses (ultra wideband, UWB: Ultra Wide Band) between a plurality of ground base stations whose positions are known and the vehicle positioning is used. Hereinafter, positioning using the propagation time of radio waves will be referred to as radio wave positioning, and the distance obtained by positioning will be referred to as positioning distance. A satellite or terrestrial base station is also referred to as a base station.

In radio wave positioning, if the radio wave reaches the receiver via a multipath path, which is different from the direct path from the base station to the receiver due to reflections on buildings, etc., an incorrect positioning will be obtained. As a countermeasure, there is known a positioning device that combines radio positioning using the propagation time of radio waves with autonomous positioning using a gyro sensor and vehicle speed sensor mounted on the vehicle to reduce the deterioration of positioning accuracy due to multipath. (See, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2002-333332

Radio positioning is performed by receiving radio waves from a plurality of base stations. For example, in GNSS, positioning is generally performed by receiving radio waves from four or more base stations. In positioning using UWB, positioning is performed by receiving radio waves from two or more base stations. Therefore, even if a conventional positioning device can receive radio waves from a single base station, it has to use the positioning position obtained by autonomous positioning. there were.

SUMMARY OF THE INVENTION The present application has been made to solve the above-described problems, and aims to provide a positioning device that suppresses errors in positioning when radio waves from one base station can be received.

The positioning device disclosed in the present application is a positioning device that is installed in a vehicle and outputs the positioning position of the vehicle, receives radio signals from one or more base stations, and for each base station, A radio positioning device that outputs information on the radio positioning distance, which is the distance to the vehicle, and the base station position, which is the position of the base station; an autonomous positioning device that outputs the position of the vehicle detected by autonomous navigation as the autonomous positioning position; a positioning position calculation unit that obtains and outputs a positioning position from the output of the positioning device and the output of the autonomous positioning device, and the positioning position calculation unit calculates the distance from the base station to the autonomous positioning position for each base station; 2. obtaining the positioning distance, outputting the autonomous positioning position as the positioning position when the autonomous positioning distance is less than or equal to the radio positioning distance for all base stations , and receiving radio signals from two or more base stations; If the autonomous positioning distance is greater than the radio positioning distance for one or more base stations, the radio positioning position is obtained using the base station position and radio positioning distance of the base station whose autonomous positioning distance is greater than the radio positioning distance. , and if the autonomous positioning distance is greater than the radio positioning distance for only one base station, the base station whose autonomous positioning distance is greater than the radio positioning distance is selected as the selected base station, and the radio positioning distance of the selected base station is selected. The position of the selected radio positioning distance in the direction from the selected base station to the autonomous positioning position is used as the radio positioning position, and the radio positioning position is output as the positioning position.

The positioning device disclosed in the present application is a positioning device that is installed in a vehicle and outputs the positioning position of the vehicle, receives radio signals from one or more base stations, and for each base station, A radio positioning device that outputs information on the radio positioning distance, which is the distance to the vehicle, and the base station position, which is the position of the base station; an autonomous positioning device that outputs the position of the vehicle detected by autonomous navigation as the autonomous positioning position; a positioning position calculation unit that obtains and outputs a positioning position from the output of the positioning device and the output of the autonomous positioning device, and the positioning position calculation unit calculates the distance from the base station to the autonomous positioning position for each base station; 2. obtaining the positioning distance, outputting the autonomous positioning position as the positioning position when the autonomous positioning distance is less than or equal to the radio positioning distance for all base stations , and receiving radio signals from two or more base stations; If the autonomous positioning distance is greater than the radio positioning distance for one or more base stations, the radio positioning position is obtained using the base station position and radio positioning distance of the base station whose autonomous positioning distance is greater than the radio positioning distance. , and if the autonomous positioning distance is greater than the radio positioning distance for only one base station, the base station whose autonomous positioning distance is greater than the radio positioning distance is selected as the selected base station, and the radio positioning distance of the selected base station is selected. The position of the selected radio positioning distance in the direction of the autonomous positioning position from the selected base station is the radio positioning position, and the radio positioning position is output as the positioning position, so when radio waves from one base station can be received positioning position error can be suppressed.

1 is a diagram showing the configuration of a positioning device according to Embodiment 1; FIG. FIG. 4 is a diagram for explaining the operation of a positioning position calculation unit according to Embodiment 1; FIG. 4 is a diagram for explaining the operation of a positioning position calculation unit according to Embodiment 1; FIG. 4 is a diagram for explaining the operation of a positioning position calculation unit according to Embodiment 1; 4 is a flowchart for explaining the operation of the positioning device according to Embodiment 1; 4 is a diagram showing the positional relationship between the radio positioning position and the autonomous positioning position obtained by the positioning position calculation unit in Embodiment 1. FIG. FIG. 4 is a diagram for explaining an estimation error when a radio wave positioning position is obtained as a positioning position by a positioning position calculation unit according to Embodiment 1; 8 is a diagram for explaining an angle φ in FIG. 7; FIG. 4 is a diagram showing an example of an omnidirectional estimation error output from an estimation error section according to Embodiment 1; FIG. FIG. 4 is a diagram for explaining an example of vehicle control using the output of the positioning device according to Embodiment 1; 1 is a schematic diagram showing an example of a hardware configuration of a positioning device according to Embodiment 1; FIG.

Hereinafter, positioning devices according to embodiments for carrying out the present application will be described in detail with reference to the drawings. In each figure, the same reference numerals denote the same or corresponding parts.

Embodiment 1.
FIG. 1 is a diagram showing the configuration of a positioning device 100 according to Embodiment 1. As shown in FIG. The positioning device 100 according to Embodiment 1 includes a radio wave positioning device 1 , an autonomous positioning device 2 , a positioning position calculator 3 , a travel route inner determination unit 4 , and an error estimator 5 . A positioning device 100 is installed in a vehicle 10 . The radio positioning device 1 is provided with a receiver for receiving radio waves from base stations via an antenna 1a installed in a vehicle 10, and the number of N base stations from the first base station to the Nth base station is provided. The radio signals from each are received at the same time. Receiving at the same time means receiving when the vehicle 10 is at the same position. Here, N is a natural number. A base station is, for example, a satellite in GNSS or a terrestrial base station in a positioning system using UWB. The radio positioning device 1 outputs the distances between each base station and the vehicle 10, which can be obtained from the propagation delay time of the radio waves received by the receiver, as the radio positioning distances _R1 to _RN . That is, the distance between the first base station and the vehicle 10 obtained by radio positioning by the radio positioning device 1 is _R1 , and the distance between the Nth base station and the vehicle 10 obtained by radio positioning by the radio positioning device 1 is R1. is _RN .

Further, the radio positioning device 1 outputs the positions of the respective base stations whose distances have been obtained as the base station position _S1 to the base station position _SN . That is, the location of the first base station is _S1 , and the location of the Nth base station is _SN . The base station locations _S1 to _SN may use information sent by radio signals from the base stations. Also, for _S1 to _SN , which are the positions of the base stations, information on the identification numbers of the base stations and the positions of the base stations indicated by the identification numbers are stored in advance in the radio positioning device 1, and radio signals from the base stations are stored in advance. Information on the location of the base station obtained by matching the identification number sent by with stored information may be used.

The autonomous positioning device 2 outputs the position of the vehicle 10 detected by the autonomous navigation as the autonomous positioning position u. The autonomous positioning device 2 includes state quantity sensors including, for example, a gyro sensor for measuring angular velocity and a vehicle speed sensor for measuring vehicle speed. Find and output u. The autonomous positioning device 2, for example, acquires the last measured position obtained immediately before from the traveling route inside determination unit 4, calculates the autonomous positioned position u from the measured value by the state quantity sensor and the last measured position obtained immediately before, and outputs it. do. Since the output value of the state quantity sensor contains an error, the autonomous positioning position u contains an error component due to autonomous positioning. When the autonomous positioning device 2 is used continuously, the autonomous positioning position u becomes a value obtained by integrating the output of the state quantity sensor, and the error component due to the autonomous positioning increases over time.

First, the positioning _position calculation unit ₃ calculates autonomous The autonomous positioning distance _rN is obtained from the autonomous positioning distance _r1 , which is the distance to the positioning position u. That is, the distance between the first base station and the autonomous positioning position u is the autonomous positioning distance _r1 , and the distance between the Nth base station and the autonomous positioning position u is the autonomous positioning distance _rN . Next, when n is a value from 1 to N, the radio positioning distance R _n and the autonomous positioning distance r _n are compared for each n from 1 to N, and the autonomous positioning distance is calculated for all n from 1 to N. When the positioning distance _rn is equal to or less than the radio positioning distance _Rn , the autonomous positioning position u is output as the positioning position. Also, the positioning position calculation unit 3 is information indicating the positioning method selected in the positioning position calculation unit 3 when the autonomous positioning distance rn is equal to _or less than the radio positioning distance _Rn for all n from 1 to N. Output autonomous positioning as selective positioning information.

When the autonomous positioning distance _{rn is greater than the radio positioning distance Rn} for two or more values from 1 to N, the positioning position _calculation unit 3 determines that the autonomous positioning distance _rn is equal to the radio positioning distance _Rn. Using the values of the base station position S _n and the radio positioning distance R _n of the base station larger than , the radio positioning position M is obtained, the radio positioning position M is output as the positioning position, and the first radio positioning is selected as the selected positioning information Output. For example, there are five base stations from the first base station to the fifth base station, _r1 is greater than _R1 , _r2 is greater than _R2 , _r3 is greater than _R3 , and _r4 is R ₄ or less, and when _r5 is _R5 or less, the values of _S1 and _R1 , _S2 and _R2 , _S3 and _R3 are used to obtain the radio positioning position M, The positioning position M is output as the positioning position. If two or more points are obtained as the radio positioning position M obtained using the values of the base station position S _n and the radio positioning distance R _n of the base station whose autonomous positioning distance r _n is greater than the radio positioning distance R _n , , the determined radio wave positioning position M closest to the autonomous positioning position u is set as the final radio wave positioning position M, and the final radio wave positioning position M is output as the positioning position.

When the autonomous positioning distance _rn is greater than the radio positioning distance _Rn only in the n-th base station, which is one base station, the positioning position calculation unit 3 selects the n-th base station as the selected base station, and Let the radio wave positioning distance _Rn , which is the distance to the vehicle 10, be the selected radio wave positioning distance, and let the position of the selected radio wave positioning distance in the direction of the autonomous positioning position u from the n-th base station, which is the selected base station, be the radio wave positioning position M, and the radio wave The positioning position M is output as the positioning position, and the second radio wave positioning is output as the selected positioning information. The radio positioning position M obtained in this manner is the selected radio positioning distance _Rn from the selected base station n-th base station, and is the closest position to the autonomous positioning position u. Further, when the autonomous positioning distance _rn is greater than the radio wave positioning distance _Rn only in the n-th base station which is one base station, the positioning position calculation unit 3 determines the direction from the selected base station to the autonomous positioning position u. The information is output to the error estimator 5 as the positioning direction.

The inside-of-travel-route determination unit 4 obtains the final positioned position from the output of the positioned position calculation unit 3 and the output of the autonomous positioning device 2, and outputs it. The traveling route inside determination unit 4 first acquires the selected positioning information from the positioning position calculation unit 3 . When autonomous positioning is acquired as the selected positioning information, the traveling route inside determination unit 4 outputs the acquired positioning position as the autonomous positioning position u, and outputs the positioning position that is the autonomous positioning position u as the final positioning position. When the traveling route inside determination unit 4 acquires the first radio wave positioning or the second radio wave positioning as the selected positioning information, the acquired positioning position is the radio wave positioning position M, and the positioning position that is the radio wave positioning position M is determined in advance. Check if it is within the driving route range. When the radio positioning position M is within the traveling route range, the radio positioning position M is output as the final positioning position. When the radio positioning position M is outside the travel route range, the autonomous positioning position acquired from the autonomous positioning device 2 is output as the final positioning position, and a positioning position change signal is output to the error estimator 5 .

The error estimating unit 5 obtains an omnidirectional estimation error having information on estimated error values in all directions that can be taken as the traveling direction of the vehicle 10 from the output of the positioning position calculating unit 3 and the output of the traveling route inside determining unit 4. Output, for example, with the east at 0 degrees and the north at 90 degrees, output the omnidirectional estimation error with information on the estimated error value from 0 degrees to 360 degrees, and output the estimated error in all directions Store the value as the previous estimated error value. When the error estimating unit 5 acquires autonomous positioning as the selected positioning information output from the positioning position calculating unit 3, the error estimating unit 5 calculates the autonomous positioning error predetermined as the previous estimated error value in all directions from 0 degrees to 360 degrees. is output as a new estimated error value, and the output estimated error value is stored as a new previous estimated error value in all directions. When the error estimating unit 5 acquires the first radio wave positioning as the selected positioning information output from the positioning position calculating unit 3, the error estimating unit 5 calculates a predetermined radio wave positioning error in all directions from 0 degrees to 360 degrees as an estimation error. omnidirectional estimation error is output as a value, and the output estimation error value is stored as a new previous estimation error value in all directions. When the second radio wave positioning is obtained as the selected positioning information output from the positioning position calculation unit 3, the error estimation unit 5 sets the estimated error value of the positioning direction output from the positioning position calculation unit 3 as the radio wave positioning error, Add a predetermined autonomous positioning error to the previous estimated error value for all directions except the positioning direction, and output the omnidirectional estimation error as a new estimated error value, and output the output estimated error value for all directions. is stored as a new previous estimation error value.

Next, the operation of the positioning position calculator 3 in Embodiment 1 will be explained using FIGS. 2 to 5. FIG. 2 to 4 are diagrams for explaining the operation of the positioning position calculation unit 3 in Embodiment 1, and FIG. 2 is a diagram for explaining the operation when the selected positioning information is the first radio wave positioning. 3 is a diagram for explaining the operation when the selective positioning information is the second radio wave positioning, and FIG. 4 is a diagram for explaining the operation when the selective positioning information is the autonomous positioning. . In FIGS. 2 to 4, the vehicle 10 on which the positioning device 100 is installed is assumed to travel within a travel route range 20 on a plane from the starting point PS to the destination PE. It is also assumed that the radio positioning device 1 receives radio waves from two base stations, the first base station BS1 and the second base station BS2, via the antenna 1a. 2 to 4, it is assumed that the first base station BS1 and the second base station BS2 are installed on the ground. For ease of explanation, it is assumed that the position within the traveling route range 20 can be uniquely determined once the distance from the first base station BS1 and the distance from the second base station BS2 are determined.

FIG. 5 is a flow chart for explaining the operation of the positioning device 100 according to the first embodiment. Step ST01 is a radio positioning step, Step ST02 is an autonomous positioning step, Step ST03 is an autonomous positioning distance calculation step, Step ST04 is an autonomous positioning determination step, Step ST05 is an autonomous positioning position determination step, Step ST06 is an autonomous positioning position final determination step, step ST07 is a radio wave positioning determination step, step ST08 is a first radio wave positioning position acquisition step, step ST09 is a second radio wave positioning position acquisition step, and step ST10. is a travel route determination step, step ST11 is a radio positioning position final determination step, step ST12 is a positioning position change step, and step ST13 is an estimation error calculation step.

In step ST01, the radio positioning device 1 receives radio signals from one or more base stations, acquires the number N of base stations for which distance information has been obtained by radio positioning, Information on radio positioning distances R ₁ to R _N , which are the distances from each base station to the vehicle 10, and base station positions S ₁ to _SN , which are the positions of the respective base stations, are acquired, and the acquired information is used as the positioning position. Output to the calculation unit 3 and proceed to step ST02. Here, N is the number of base stations, so it is a natural number. In the examples shown in FIGS. 2 to 4, N is 2, the position of the first base station BS1 is _S1 , the position of the second base station BS2 is _S2 , and is obtained by radio positioning. The radio positioning distance, which is the distance from the first base station BS1 to the vehicle 10, is _R1 , and the radio positioning distance, which is the distance from the second base station BS2 to the vehicle 10 obtained by radio positioning, is _R2 . For example, when N, which is the number of base stations whose distances are obtained by radio positioning, is 4, radio positioning distances R ₁ , R ₂ , which are the distances from each base station to the vehicle 10 obtained by radio positioning. We will have R ₃ , R ₄ and the base station positions S ₁ , S ₂ , S ₃ , S ₄ , which are the positions of the respective base stations. In the following description, n is any value from 1 to N, the position of the n-th base station BSn is S _n , and the radio positioning distance, which is the distance from each n-th base station BSn to the vehicle 10 by radio positioning, is R _n . .

In step ST02, the autonomous positioning device 2 acquires the autonomous positioning position u, which is the position of the vehicle 10 detected by autonomous navigation, outputs the acquired information to the positioning position calculator 3, and proceeds to step ST03. In the example shown in FIG. 2, the acquired autonomous positioning position is the position a, in the example shown in FIG. 3, the acquired autonomous positioning position is the position b, and in the example shown in FIG. 4, the acquired autonomous positioning position is the position of c.

In step ST03, the positioning position calculator 3 calculates the distance from each base station to the autonomous positioning position u based on the information on the base station positions _S1 to _SN , which are the positions of the respective base stations, and the information on the autonomous positioning position u. Then, the autonomous positioning distances r ₁ to r _N are calculated, and the process proceeds to step ST04. In the example shown in FIG. 2, the autonomous positioning distance r ₁ is the distance from the autonomous positioning position a to the first base station BS1, and the autonomous positioning distance r is the distance from the autonomous positioning position a to the second base station BS2. ₂ is calculated. Similarly, in the example shown in FIG. 3, the autonomous positioning distance r ₁ ′ is the distance from the autonomous positioning position b to the first base station BS1, and the distance from the autonomous positioning position b to the second base station BS2 is The autonomous positioning distance r ₂ ′ is calculated, and in the example shown in FIG. 4, the autonomous positioning distance r ₁ ″, which is the distance from the autonomous positioning position c to the first base station BS1, Calculate the autonomous positioning distance r ₂ ″, which is the distance to the station BS2. In the following description, n is any value from 1 to N, and the distance from the n-th base station BSn to the autonomous positioning position u is _rn .

In step ST04, the positioning position calculation unit 3 confirms whether or not the autonomous positioning distance _rn is equal to or less than the radio wave positioning distance _Rn for all n, where n is a number from 1 to N. If r _n is equal to or less than the radio positioning distance R _n , proceed to step ST05; otherwise, proceed to step ST07. In step ST05, the positioning position calculation unit 3 outputs the autonomous positioning position u as the positioning position to the travel route determination unit 4, and outputs a signal indicating the autonomous positioning as the selected positioning information to the travel route determination unit 4 and the error estimation unit 5. , and proceeds to step ST06.

In the example shown in FIG. 4, the autonomous positioning distance r ₁ ″ is less than or equal to the radio positioning distance R ₁ , and the autonomous positioning distance r ₂ ″ is less than or equal to the radio positioning distance R ₂ . It outputs the determined position to the travel route inside determination unit 4 , and outputs a signal indicating autonomous positioning to the travel route inside determination unit 4 and the error estimation unit 5 as the selected positioning information. When a multipath occurs and radio waves from the n-th base station BSn are reflected or refracted and reach the positioning device 100 installed in the vehicle 10, the magnitude of the acquired radio positioning distance _Rn becomes larger than the actual distance. a large value. When the autonomous positioning distance _rn is less than or equal to the radio positioning distance _Rn , there is a possibility that the magnitude of the radio positioning distance _Rn is larger than the actual distance due to multipath. By outputting the autonomous positioning position u as the positioning position without using the information of _n , an erroneous positioning position is not obtained due to multipath.

In step ST06, the inside-of-travel-route determination unit 4 acquires the autonomous positioning as the selected positioning information from the positioning position calculation unit 3, so the positioning position that is the autonomous positioning position u acquired from the positioning position calculation unit 3 is used as the final positioning position. output and proceed to step ST13. In the example shown in FIG. 4 , the inside-of-travel-route determination unit 4 acquires autonomous positioning as the selected positioning information from the positioning position calculation unit 3 , so the positioning position that is the autonomous positioning position c acquired from the positioning position calculation unit 3 is used as the final positioning position. Output as positioning position.

In step ST07, the positioning position calculator 3 checks whether the autonomous positioning distance r _n is greater than the radio positioning distance R _n only for one n-th base station BSn, and determines whether the autonomous positioning distance r n for only one base station BSn. If _n is greater than the radio positioning distance _Rn , proceed to step ST09; otherwise, that is, if the autonomous positioning distance _rn for two or more base stations is greater than the radio positioning distance _Rn , proceed to step ST08. move on. In step ST08, the positioning position calculator 3 obtains the radio positioning position M using the base station position _Sn of the base station whose autonomous positioning distance _rn is greater than the radio positioning distance _Rn and the information on the radio positioning distance _Rn . Then, it outputs the radio wave positioning position M as the measured position to the travel route determination unit 4, outputs a signal indicating the first radio wave positioning as the selected positioning information to the travel route determination unit 4 and the error estimation unit 5, and proceeds to step ST10. move on.

In the example shown in FIG. 2, the autonomous positioning distance _r1 is greater than the radio positioning distance _R1 , the autonomous positioning distance _r2 is greater than the radio positioning distance _R2 , and two or more base stations have autonomous positioning distances _rn . Since the radio positioning distance Rn is greater than the radio positioning distance _Rn , the positioning position calculation unit 3 calculates the base station position _{S1 of the first base station BS1 whose autonomous positioning distance r1 is greater than the radio positioning distance R1 and the} radio positioning distance _R1 , From the base station position _S2 of the second base station BS2 whose autonomous positioning distance _r2 is greater than the radio positioning distance _R2 and the radio positioning distance _R2 , the radio positioning position A is obtained, and the radio positioning position A is used as the positioning position. It outputs to the traveling route inside determination unit 4 and outputs a signal indicating the first radio wave positioning as the selected positioning information to the traveling route inside determination unit 4 and the error estimation unit 5 . When the autonomous positioning distance _rn is greater than the radio positioning distance _Rn , there is a high possibility that an accurate value is obtained as the radio positioning distance _Rn without the occurrence of multipath _. The radio positioning position M is obtained without being affected by multipath by obtaining the radio positioning position M using the base station position S _n of the base station larger than the radio positioning distance R _n and the information of the radio positioning distance R _n . be able to.

In step ST09, the positioning position calculator 3 selects the n-th base station BSn whose autonomous positioning distance _rn is greater than the radio positioning distance _Rn , and selects the radio positioning distance _Rn of the selected base station. , the position of the selected radio wave positioning distance _{R n} in the direction from the base station position Sn of the selected base station to the autonomous positioning position u is set as the radio wave positioning position M, and the radio wave positioning position M is output to the traveling route determination unit 4 as the positioning position. Then, a signal indicating the second radio wave positioning as the selected positioning information is output to the traveling route inside determining section 4 and the error estimating section 5, and the process proceeds to step ST10.

In the example shown in FIG. 3, the autonomous positioning distance r ₁ ′ is greater than the radio positioning distance R ₁ , the autonomous positioning distance r ₂ ′ is less than or equal to the radio positioning distance R ₂ , and only one first base station BS1 is autonomously positioned. Since the distance r _n is greater than the radio positioning distance R _n , the positioning position calculator 3 selects the first base station BS1 whose autonomous positioning distance r ₁ ′ is greater than the radio positioning distance R ₁ as the selected base station. The radio positioning distance _R1 is set as the selected radio positioning distance. Furthermore, the position of the selected radio wave positioning distance R ₁ in the direction from the base station position S ₁ of the selected base station to the autonomous positioning position b is set as the radio wave positioning position B, and the radio wave positioning position B is output to the traveling route determination unit 4 as the positioning position. Then, it outputs a signal indicating the second radio wave positioning as the selected positioning information to the traveling route inside determining section 4 and the error estimating section 5 . Since the autonomous positioning distance r ₂ ′ is less than or equal to the radio positioning distance R ₂ , there is a possibility that the magnitude of the radio positioning distance R ₂ may be larger than the actual distance due to multipath, so the first base station Using the information of the base station position S ₁ and the radio positioning distance R ₁ of BS 1 and the information of the autonomous positioning position b to obtain the radio positioning position B, thereby obtaining the positioning position without being affected by multipath. can be done. Further, the radio wave positioning position B obtained in this manner is always closer to the correct positioning position P than the autonomous positioning position b.

FIG. 6 is a diagram showing the positional relationship between the radio positioning position B and the autonomous positioning position b obtained by the positioning position calculator 3 in Embodiment 1 in the example shown in FIG. FIG. 6 shows the positional relationship among the first base station BS1, the radio positioning position B, and the autonomous positioning position b in the example shown in FIG. In FIG. 6, the position of the first base station BS1 is the origin O, the correct positioning position P is on the x-axis, and the distance between the correct positioning position P and the first base station BS1 at the origin O is the radio positioning distance R ₁ , and an axis perpendicular to the x-axis is the y-axis. Let θ be the angle bOP, and 0<θ<π. At this time, the square of the length of the line segment bP is represented by the following formula (1), the square of the length of the line segment BP is represented by the following formula (2), and from the square of the length of the line segment bP A value obtained by subtracting the square of the length of the line segment BP is represented by the following equation (3).

Here, in equation (3), since the maximum value of cos θ is 1 when 0<θ<π, the minimum value of (r ₁ '+R ₁ -2R ₁ cos θ) is (r ₁ '-R ₁ ). . 3 and 6 show an example in which the autonomous positioning range r ₁ 'is greater than the radio positioning range R ₁ , so (r ₁ '−R ₁ ) is always positive, and is shown in equation (3). The value obtained by subtracting the square of the length of the line segment BP from the square of the length of the line segment bP is always positive. Therefore, the length of the line segment BP is always shorter than the length of the line segment bP, and the radio positioning position B is always closer to the correct positioning position P than the autonomous positioning position b. Therefore, even if radio signals from multiple base stations cannot be received, if the radio signal from one base station can be received and the autonomous positioning distance is greater than the radio positioning distance, the positioning is more correct than the autonomous positioning position b. A radio positioning position B located near the position P can be output as the positioning position.

In the flowchart shown in FIG. 5 , in step ST<b>10 , the travel route inside determination unit 4 acquires the selected positioning information and the measured position from the measured position calculation unit 3 . In step ST10, the selected positioning information acquired by the traveling route inside determination unit 4 is the first radio wave positioning or the second radio wave positioning, and the positioning position acquired by the traveling route inside determination unit 4 is the radio wave positioning position M. In step ST10, the inside-of-travel-route determining unit 4 confirms whether or not the positioning position, which is the radio wave positioning position M, is within the predetermined traveling route range 20, and confirms whether the positioning position, which is the radio wave positioning position M, is determined in advance. If it is within the travel route range 20, the process proceeds to step ST11.

In step ST11, the traveling route inside determination unit 4 outputs the positioning position, which is the radio positioning position M, as the final positioning position, and proceeds to step ST13. In step ST12, the traveling route inside determination unit 4 acquires the autonomous positioning position u from the autonomous positioning device 2, outputs the autonomous positioning position u as the final positioning position, outputs a positioning position change signal to the error estimation unit 5, Go to step ST13. When the positioning position, which is the radio positioning position M, is outside the predetermined travel route range 20, the radio positioning distance may be shorter than the actual distance due to an abnormality in the device or noise. . Therefore, by outputting the autonomous positioning position u as the final positioning position when the positioning position that is the radio positioning position M is outside the predetermined travel route range 20, the radio positioning position that is shorter than the actual distance is output. Using distance information can be avoided.

In step ST13, the error estimating section 5 obtains an omnidirectional estimation error including estimated error values in all possible directions of travel of the vehicle 10 from the output of the positioning position calculating section 3 and the output of the traveling route inside determining section 4. and stores the output estimated error values in all directions as previous estimated error values, and terminates the process. Specifically, in step ST13, when the error estimating unit 5 acquires autonomous positioning as the selected positioning information or acquires a positioning position change signal, the error estimating unit 5 adds the autonomous positioning error to the previous estimated error value in all directions. Output the omnidirectional estimation error with the added value as the new estimation error value, and estimate the radio wave positioning error in all directions when the first radio wave positioning is acquired as the selective positioning information without acquiring the positioning position change signal. When the omnidirectional estimation error is output as the error value and the second radio wave positioning is obtained as the selected positioning information without obtaining the positioning position change signal, the radio wave positioning error is output as the positioning direction estimation error value and the positioning direction is output. In directions other than , a value obtained by adding an autonomous positioning error to the previous estimated error is output as an estimated error.

The estimation error will be described with reference to FIGS. 7 and 8. FIG. FIG. 7 is a diagram for explaining the actual estimation error 30 when the radio positioning position B is obtained as the positioning position by the positioning position calculator 3 in Embodiment 1 in the example shown in FIG. FIG. 8 is a diagram for explaining the angle φ in FIG. 7. FIG. In FIG. 7, the direction of the correct positioning position P viewed from the first base station BS1 is defined as the positive direction of the x-axis, and the estimated error value in each direction is represented by the distance from the origin 0 as indicated by the dotted line. 30. In FIG. 8, the position of the first base station BS1 is the origin O, the correct positioning position P is on the x-axis, and the distance between the correct positioning position P and the first base station BS1 at the origin O is the radio positioning distance _R1. and the axis perpendicular to the x-axis is the y-axis. In FIG. 8, the autonomous positioning position b is located at a position separated from the correct positioning position P by an estimated error value d due to autonomous positioning. Let φ be the angle QOP when the point Q is the point of intersection of a circle with a radius _R1 centered at the origin O and a circle with a radius d centered at the correct positioning position P. φ is an angle represented, for example, by the following equation (4).

As shown in FIG. 7, for the estimated error 30, the radio wave positioning error D is the estimated error value in the positive direction of the x-axis, which is the direction in which the correct positioning position P is viewed from the first base station BS1. Assuming that the positive direction of the x-axis is 0 degrees, the estimated error 30 increases as the angle increases. Become. Note that the estimated error value d due to autonomous positioning increases over time. In FIG. 7, the distance from the origin 0 to _EB is the estimated error value when the angle is θ, and the distance from the origin 0 to _EB is larger than the radio positioning error D and larger than the estimated error value d by autonomous positioning. small. In FIG. 7, the distance from the origin 0 to _EQ is the estimated error value when the angle is φ, and the distance from the origin 0 to _EQ is the estimated error value d by autonomous positioning. However, in actual operation, the position of the correct positioning position P is not known, but since the radio positioning distance _R1 is sufficiently larger than the estimated error value d by autonomous positioning, in the error estimator 5, φ=0 7, the estimated error value in the positive direction of the x-axis is the radio wave positioning error D, and the estimated error value in the directions other than the positive direction of the x-axis is the estimated error value d by autonomous positioning. Output the estimated error.

FIG. 9 is a diagram showing an example of the omnidirectional estimation error output from the error estimator 5 according to the first embodiment. FIG. 9 shows that the vehicle 10 travels in a traveling route range 20 from the departure point PS to the destination PE on a plane, and the positioning position is indicated by the positioning device 100 according to Embodiment 1 while traveling. 100 shows the omnidirectional estimation error when processing is always performed in a state where the autonomous positioning distance r ₁ ′ is greater than the radio positioning distance R ₁ only for one first base station BS1 as shown in FIG. there is In FIG. 9, for ease of explanation, the radio positioning error D is assumed to be 0, and the estimated error value d due to autonomous positioning is assumed to be constant regardless of the passage of time. The omnidirectional estimation error EE1 when the departure point PS is output as the positioning position is 0, which is the radio wave positioning error D, in the direction from the first base station BS1 toward the departure point PS, which is the positioning position. is the estimated error value d by autonomous positioning. While the vehicle 10 is traveling from the departure point PS to the waypoint P1, the direction toward the positioning position from the first base station BS1 changes, and the omnidirectional estimation error EE2 when the waypoint P1 is output as the positioning position is The angle at which the estimated error value is 0, which is the radio wave positioning error D, is larger than the estimated error EE1. In the omnidirectional estimation error EE3 when the vehicle 10 rotates 90 degrees to the right at the waypoint P1, the angle at which the estimated error value is 0, which is the radio wave positioning error D, becomes even larger. The omnidirectional estimation error EE4 is obtained when the waypoint P2 is output as the positioning position, and the omnidirectional estimation error EE5 is obtained when the vehicle 10 rotates 90 degrees to the right at the waypoint P2. EE6 is the result when the waypoint P3 is output as the measured position, the omnidirectional estimation error EE7 is the result when the vehicle 10 is rotated 90 degrees to the right at the waypoint P3, and the omnidirectional estimation error EE8 is the measured position. is output when the destination PE is output as . In the omnidirectional estimation error, the angle at which the estimated error value becomes the radio wave positioning error D increases as the vehicle 10 travels along the travel route from the departure point PS toward the destination PE.

In the first embodiment, the travel route range 20 is described as being on a plane, but the travel route range 20 may be in a three-dimensional space. Further, in the case where the range of the travel route of the vehicle 10 is controlled by electromagnetic induction wires, the range in which the electromagnetic induction wires are installed may be the travel route region 20 . 2 to 4 show the case where there are two base stations, but the number of base stations may be one or more, and may be plural. Although the base station is installed on the ground in Embodiment 1, the base station may be a GNSS satellite. If the base stations are GNSS satellites, for example, radio signals from two or more base stations may be received, and the processing shown in Embodiment 1 may be performed after correcting the clock error from the radio signals. When the output of the positioning device 100 according to Embodiment 1 is used for controlling the vehicle 10, the control may be performed with a margin according to the estimated error value of each direction.

FIG. 10 is a diagram for explaining an example of vehicle control using the output of the positioning device 100 according to the first embodiment. FIG. 10 shows a state in which the vehicle 10 on which the positioning device 100 is installed is traveling in a travel route range 20 from the starting point PS to the destination PE on a plane. FIG. 10 shows how the positioning device 100 outputs the positioning position D and the omnidirectional estimation error EE10 while the vehicle 10 is traveling at the correct positioning position P, which is the actual position. It shows the traveling direction of the vehicle 10 when the position D is output. In the example shown in FIG. 10, the estimated error value in the direction opposite to the traveling direction of the vehicle 10 is a large value, and the correct positioning position P, which is the actual position of the vehicle 10, is located ahead of the positioning position D in the traveling direction. ing. In this way, when the estimated error value in the direction opposite to the traveling direction of the vehicle 10 is a large value, for example, when the estimated error value in the direction opposite to the traveling direction of the vehicle 10 is larger than a predetermined threshold value, Since there is a high possibility that the correct positioning position P, which is the actual position of the vehicle 10, is positioned ahead of the positioning position D in the direction of travel, it is possible that the vehicle 10 will travel in a portion near the end of the travel route range 20. , the speed of the vehicle 10 is reduced. Further, when the estimated error value in the direction opposite to the traveling direction of the vehicle 10 is a small value, for example, when the estimated error value in the direction opposite to the traveling direction of the vehicle 10 does not exceed a predetermined threshold value, the vehicle 10 Since there is a small possibility that the correct positioning position P, which is the actual position of the vehicle 10, is positioned ahead of the positioning position D in the direction of travel, control is performed to maintain the speed of the vehicle 10 so as not to waste time. do.

Further, the positioning device 100 according to Embodiment 1 may be configured without the travel route inside determination unit 4 . In this case, the measured position that is the output of the positioned position calculator 3 becomes the measured position that is the output of the positioning device 100 as it is. Further, when the error estimating unit 5 acquires autonomous positioning as the selected positioning information from the positioning position calculating unit 3, the error estimating unit 5 adds a predetermined autonomous positioning error to the previous estimated error value in all directions as an estimated error value. , and when the first radio wave positioning is acquired as the selective positioning information from the positioning position calculation unit 3, a predetermined radio wave positioning error is output as an estimated error value in all directions, and the selected positioning error is output from the positioning position calculation unit When the second radio wave positioning is acquired as information, the radio wave positioning error is output as the estimated error value of the positioning direction, and in the directions other than the positioning direction, the value obtained by adding the autonomous positioning error to the previous estimated error value is output as the estimated error value. do.

As described above, the positioning device 100 according to Embodiment 1 is installed in the vehicle 10 and outputs the positioning position of the vehicle 10, receives radio signals from one or more base stations, For each base station, a radio positioning device 1 that outputs information on the radio positioning distance, which is the distance from the base station to the vehicle 10, and the base station position, which is the position of the base station, and the position of the vehicle 10 detected by autonomous navigation. An autonomous positioning device that outputs as an autonomous positioning position, and a positioning position calculation unit 3 that obtains and outputs a positioning position from the output of the radio positioning device 1 and the output of the autonomous positioning device 2, and the positioning position calculation unit 3 outputs each For each base station, determine the autonomous positioning distance, which is the distance from the base station to the autonomous positioning position, and output the autonomous positioning position as the positioning position when the autonomous positioning distance is less than or equal to the radio positioning distance for all base stations. If the autonomous positioning distance of the base station is greater than the radio positioning distance, use the base station position and radio positioning distance of the base station whose autonomous positioning distance is greater than the radio positioning distance to obtain the radio positioning position and output it as the positioning position. However, if the autonomous positioning distance is greater than the radio positioning distance for only one base station, the base station whose autonomous positioning distance is greater than the radio positioning distance is selected as the selected base station, and the radio positioning distance of the selected base station is selected. The position of the selected radio positioning distance in the direction of the autonomous positioning position from the selected base station is used as the radio positioning position, and the radio positioning position is output as the positioning position. Positional errors can be reduced.

11 is a schematic diagram showing an example of the hardware configuration of the positioning device according to Embodiment 1. FIG. The positioning position calculation unit 3 , the travel route inside determination unit 4 , and the error estimation unit 5 are implemented by a processor 201 such as a CPU (Central Processing Unit) that executes programs stored in a memory 202 . The memory 202 is also used as a temporary storage device for each process executed by the processor 201 . Also, a plurality of processing circuits may work together to perform the functions described above. Furthermore, the above functions may be realized by dedicated hardware. When dedicated hardware implements the above functions, the dedicated hardware may be, for example, a single circuit, multiple circuits, a programmed processor, an ASIC, an FPGA, or a combination thereof. The above functions may be realized by a combination of dedicated hardware and software, or a combination of dedicated hardware and firmware. The memory 202 is, for example, RAM, ROM, flash memory, non-volatile or volatile semiconductor memory such as EPROM, magnetic disk, optical disk, or a combination thereof. The processor 201, the memory 202, the radio positioning device 1 and the autonomous positioning device 2 are bus-connected to each other.

Although the present application describes exemplary embodiments, the various features, aspects, and functions described in the embodiments are not limited to application of particular embodiments, alone or Various combinations are applicable to the embodiments.
Therefore, countless modifications not illustrated are envisioned within the scope of the technology disclosed in the present application. For example, the modification, addition, or omission of at least one component shall be included.

1 Radio Positioning Device 1a Antenna 2 Autonomous Positioning Device 3 Positioning Position Calculation Unit 4 Driving Route Inner Determining Unit 5 Error Estimating Unit 10 Vehicle 20 Driving Route Range 30 Estimation Error 100 Positioning Device 201 Processor 202 memory.

Claims (4)

A positioning device that is installed in a vehicle and outputs a positioning position of the vehicle,
Receives radio signals from one or more base stations, and outputs, for each of the base stations, radio positioning distance, which is the distance from the base station to the vehicle, and base station position information, which is the position of the base station. a radio positioning device that
an autonomous positioning device that outputs the position of the vehicle detected by autonomous navigation as an autonomous positioning position;
A positioning position calculation unit that obtains and outputs the positioning position from the output of the radio positioning device and the output of the autonomous positioning device,
The positioning position calculation unit,
Obtaining an autonomous positioning distance, which is the distance from the base station to the autonomous positioning position, for each of the base stations;
outputting the autonomous positioning position as the positioning position when the autonomous positioning distance is equal to or less than the radio positioning distance for all the base stations;
When the radio positioning device receives radio signals from two or more of the base stations, and the autonomous positioning distance is greater than the radio positioning distance for the two or more base stations, the autonomous positioning distance is greater than the radio wave determining a radio positioning position using the base station position and the radio positioning distance of the base station greater than the positioning distance, and outputting the radio positioning position as the positioning position;
When the autonomous positioning distance is greater than the radio positioning distance for only one base station, the base station having the autonomous positioning distance greater than the radio positioning distance is selected as a selected base station, and the radio wave of the selected base station is selected. The positioning distance is a selected radio wave positioning distance, the position of the selected radio wave positioning distance in the direction from the selected base station to the autonomous positioning position is the radio wave positioning position, and the radio wave positioning position is output as the positioning position. positioning device. A travel route determination unit that obtains and outputs a final positioning position from the output of the positioning position calculation unit and the output of the autonomous positioning device,
The positioning position calculation unit,
when the autonomous positioning distance is less than or equal to the radio positioning distance for all of the base stations, outputting autonomous positioning as selected positioning information together with the positioning position;
When the radio positioning device receives radio signals from two or more of the base stations, and the value of the autonomous positioning distance is greater than the value of the radio positioning distance for two or more of the base stations, the positioning position and output the first radio wave positioning as the selected positioning information,
when the autonomous positioning distance is greater than the radio positioning distance only for one of the base stations, outputting a second radio positioning as the selected positioning information together with the positioning position;
The inside of the traveling route determination unit
when the autonomous positioning is acquired as the selected positioning information, outputting the positioning position as the final positioning position;
Acquiring the first radio positioning or the second radio positioning as the selected positioning information, and outputting the positioning position as the final positioning position when the positioning position is within a predetermined traveling route range,
The first radio positioning or the second radio positioning is obtained as the selected positioning information, and when the positioning position is outside the driving route range, the autonomous positioning position obtained from the autonomous positioning device is used as the final positioning. 2. The positioning device according to claim 1, wherein the position is output. obtaining and outputting an omnidirectional estimation error including estimation error values in all directions that can be taken as the traveling direction of the vehicle from the output of the positioning position calculation unit, and outputting the estimation error values in all directions that have been output as previous estimation error values; and an error estimator that stores as
The positioning position calculation unit,
when the autonomous positioning distance is less than or equal to the radio positioning distance for all of the base stations, outputting autonomous positioning as selected positioning information together with the positioning position;
When the radio positioning device receives radio signals from two or more of the base stations, and the value of the autonomous positioning distance is greater than the value of the radio positioning distance for two or more of the base stations, the positioning position and output the first radio wave positioning as the selected positioning information,
When the autonomous positioning distance is greater than the radio positioning distance for only one base station, a second radio positioning is output as the selected positioning information together with the positioning position, and the selected base station goes to the autonomous positioning position. Output the positioning direction, which is the direction,
The error estimator is
when the autonomous positioning is acquired as the selected positioning information from the positioning position calculation unit, in all directions, a value obtained by adding a predetermined autonomous positioning error to the previous estimated error value is output as the estimated error value;
when the first radio wave positioning is obtained as the selected positioning information from the positioning position calculation unit, outputting a predetermined radio wave positioning error as the estimated error value in all directions;
When the second radio wave positioning is obtained as the selected positioning information from the positioning position calculation unit, the radio wave positioning error is output as the estimated error value in the positioning direction, and the previous estimation error is output in directions other than the positioning direction. 2. The positioning device according to claim 1, wherein a value obtained by adding the autonomous positioning error to a value is output as the estimated error value. Based on the output of the positioning position calculation unit and the output of the travel route inside determination unit, an omnidirectional estimation error including estimated error values of all directions that can be taken as the traveling direction of the vehicle is obtained and output. An error estimating unit that stores the estimated error value as a previous estimated error value,
The positioning position calculation unit,
when the autonomous positioning distance is greater than the radio positioning distance for only one of the base stations, outputting a positioning direction that is a direction from the selected base station to the autonomous positioning position;
The inside of the traveling route determination unit
when outputting the autonomous positioning position acquired from the autonomous positioning device as the final positioning position, outputting a positioning position change signal;
The error estimator is
When the autonomous positioning is acquired as the selected positioning information from the positioning position calculation unit, or when the positioning position change signal is acquired from the travel route inside determination unit, the previous estimation error value is predetermined in all directions. outputting the omnidirectional estimation error obtained by adding the obtained autonomous positioning error to the estimated error value;
When the first radio wave positioning as the selected positioning information is obtained from the positioning position calculation unit without acquiring the positioning position change signal from the traveling route inside determination unit, a predetermined radio wave positioning error is obtained in all directions. outputting the omnidirectional estimation error as the estimated error value;
When the second radio wave positioning is obtained as the selected positioning information from the positioning position calculation unit without obtaining the positioning position change signal from the traveling route inside determination unit, the radio wave positioning is obtained as the estimated error value of the positioning direction. 3. The positioning apparatus according to claim 2, wherein an error is output, and a value obtained by adding the autonomous positioning error to the previous estimated error value is output as the estimated error value in directions other than the positioning direction.

Images