JP7016782B2 - Mobile devices, programs and methods for estimating initial orientation - Google Patents

Description

The present invention relates to a technique for hybrid positioning using both absolute positioning and relative positioning indoors.

Conventionally, in order to estimate the user's position outdoors, there is a technique that combines absolute position positioning by GPS (Global Positioning System) in a portable device and relative position positioning by an acceleration / magnetic sensor (see, for example, Non-Patent Document 1). .. According to this technique, the absolute position and the relative position obtained as the positioning result can be combined by the Kalman filter to determine the position with high accuracy.

On the other hand, since GPS cannot be used indoors, a beacon for short-range wireless communication is used for absolute positioning. As short-range wireless communication, there is BLE (Bluetooth Low Energy) using Bluetooth (registered trademark). BLE is standardized as "low power consumption version Bluetooth" by "Bluetooth SIG" which is a specification development organization of short-range wireless standard Bluetooth. In addition, iBeacon (registered trademark) based on Apple's iOS 7 or later OS is also based on BLE.

In order to estimate the user position indoors, there is a technique for switching between absolute position positioning using BLE and relative position positioning of PDR (Pedestrian Dead Reckoning) of a portable device (see, for example, Non-Patent Document 2). The PDR, which is called walking autonomous navigation, uses an acceleration / angular velocity sensor mounted on a mobile device. According to this technique, when all the received signal strength Intensity (RSSI) observed from the BLE beacon tends to decrease, the relative positioning of the PDR is switched to. Further, when it is determined that the position is directly under the BLE beacon during the relative positioning of the PDR, the position is switched to the absolute positioning of the BLE. That is, the absolute positioning and the relative positioning of the portable device indoors are switched according to the reception intensity of the BLE beacon.

Ryo Ogawara, et al., "Study on Position Estimating System Based on GPS Positioning Information and Sensor Information", IPSJ Journal Vol.56, No.1, 2-12, 2015-01-15, [online], [Heisei Search on September 8, 2018], Internet <URL: https://ipsj.ixsq.nii.ac.jp/ej/?action=repository_uri&item_id=112719&file_id=1&file_no=1> Miyoshi Horikawa, et al., "Proposal of hybrid indoor positioning method using BLE positioning and PDR", IPSJ Research Report, Vol.2015-CDS-14 No.13, 2015/10/2, [online] , [Search on September 8, 2018], Internet <URL: https://ipsj.ixsq.nii.ac.jp/ej/index.php?action=pages_view_main&active_action=repository_action_common_download&item_id=145223&item_no=1&attribute_id=1&file_no=1&page_id= 13 & block_id = 8 ＞

In the case of absolute positioning of BLE, the portable device stores the position (floor map) of the tag device arranged indoors in advance. Then, the portable device receives BLE beacons from a plurality of tag devices and positions the absolute position by a three-point survey based on the reception intensity of each BLE beacon.
However, when indoors, radio waves are reflected and diffracted by walls and installations. Further, when a shielding obstacle suddenly occurs between the tag device and the mobile terminal, the reception strength changes even at the same absolute position. That is, in the case of absolute positioning of BLE, the reception intensity of the BLE beacon is easily affected by the surrounding environment. As a result, the positioning accuracy of the absolute position has to be unstable.

Further, in the case of relative position positioning of PDR, when using only the acceleration / angular velocity sensor, it is not possible to know the absolute direction of the terminal (eg, the direction with the north as 0 degree). This is because the accelerometer can only acquire the direction of gravity, it cannot obtain information on the direction perpendicular to the direction of gravity, and the angular velocity sensor can only acquire the angular velocity, that is, the amount of change in the direction. This is because the absolute direction cannot be obtained. When using a magnetic sensor, the absolute orientation can be obtained by detecting the geomagnetism, but the magnetic sensor needs to be calibrated in advance, and the magnetic field distortion due to the building itself indoors. It is difficult to obtain more accurate geomagnetism. Therefore, the reliability is improved by calibrating the initial direction at the start of positioning in advance or estimating the initial direction accurately.
However , if the initial orientation setting fails, there is a problem that the accuracy is greatly deteriorated.

Therefore, an object of the present invention is to provide a portable device, a program, and a method capable of estimating the initial direction of relative positioning using absolute positioning.

According to the present invention, in a portable device,
From the start of positioning, the first absolute position positioning means for acquiring the first absolute position of the mobile device in chronological order, and
Relative positioning means that acquires the relative position of the mobile device in chronological order from the start of positioning,
A second absolute position positioning means that sets a plurality of temporary initial directions in advance and calculates a time series of a second absolute position from a time series of relative positions for each temporary initial direction from the start of positioning.
With a predetermined condition determination means that outputs a selection instruction when a predetermined time from the positioning start time is reached or when a predetermined distance from the positioning start position is reached.
When the selection instruction is output, the one most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute position is selected. It is characterized by having an initial direction selection means for selecting a temporary initial direction in the time series of the above as an initial direction.

According to another embodiment of the portable device of the present invention.
It is also preferable to set the plurality of temporary initial orientations so that the temporary initial orientations are at equal angles between each other.

According to another embodiment of the portable device of the present invention.
The first absolute position positioning means positions the first absolute position using a communication device that receives short-range radio waves from a plurality of other devices.
It is also preferable that the relative position positioning means measures the relative position by using an acceleration sensor and an angular velocity sensor.

According to another embodiment of the portable device of the present invention.
The communication device receives BLE (Bluetooth Low Energy) or iBeacon (registered trademark) radio waves and uses them for positioning.
It is also preferable that the accelerometer and the angular velocity sensor are for pedestrian autonomous navigation (PDR).

According to another embodiment of the portable device of the present invention.
The optimum position is calculated using the first absolute position output from the first absolute position positioning means, the initial direction selected by the initial direction selection means, and the relative position output from the relative position positioning means. It is also preferable to have further hybrid positioning means.

According to another embodiment of the portable device of the present invention.
It is also preferable that the initial direction selection means selects the one having the smallest mean square error as compared with the time series of the first absolute position among the time series of the plurality of second absolute positions.

According to another embodiment of the portable device of the present invention.
It is also preferable that the predetermined distance in the predetermined condition determination means is a preset cumulative movement distance and / or a linear distance from the positioning start position.

According to the present invention, in a program for operating a computer mounted on a mobile device,
From the start of positioning, the first absolute position positioning means for acquiring the first absolute position of the mobile device in chronological order, and
Relative positioning means that acquires the relative position of the mobile device in chronological order from the start of positioning,
A second absolute position positioning means that sets a plurality of temporary initial directions in advance and calculates a time series of a second absolute position from a time series of relative positions for each temporary initial direction from the start of positioning.
With a predetermined condition determination means that outputs a selection instruction when a predetermined time from the positioning start time is reached or when a predetermined distance from the positioning start position is reached.
When the selection instruction is output, the one most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute position is selected. It is characterized in that the computer functions as an initial direction selection means for selecting a temporary initial direction in the time series of.

According to the present invention, in the method of determining the initial orientation of a portable device,
The mobile device is
From the start of positioning, the first step of acquiring the first absolute position of the mobile device in chronological order, and
From the start of positioning, the second step of acquiring the relative position of the mobile device in chronological order,
A third step in which a plurality of temporary initial directions are set in advance and the time series of the second absolute position is calculated from the time series of relative positions for each temporary initial direction from the start of positioning.
The fourth step of outputting the selection instruction when the predetermined time from the positioning start time is reached or when the predetermined distance from the positioning start position is reached.
When the selection instruction is output, the one most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute position is selected. It is characterized by executing the fifth step of selecting the tentative initial direction in the time series as the initial direction.

According to the portable device, program and method of the present invention, the initial orientation of relative positioning can be estimated using absolute positioning.

It is a functional block diagram of the portable device in this invention. It is explanatory drawing which shows the time series of the 1st absolute position. It is explanatory drawing which shows the plurality of tentative initial directions in this invention. It is explanatory drawing which shows the time series of the 2nd absolute position which corresponded the relative position to the tentative initial direction. It is explanatory drawing which shows the comparison between the absolute position and the relative position based on a plurality of tentative initial directions. It is explanatory drawing which shows the initial orientation determined by this invention. It is explanatory drawing which shows the process of absolute position positioning until the initial direction is determined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a functional configuration diagram of a portable device according to the present invention.

According to FIG. 1, the portable device 1 has a communication device 101 and an acceleration / angular velocity sensor 102 as hardware.
Further, according to FIG. 1, the portable device 1 includes a first absolute positioning unit 11, a relative positioning unit 12, a second absolute positioning unit 13, a predetermined condition determination unit 14, and an initial orientation selection. It has a unit 15 and a hybrid positioning unit 16. These functional components are realized by executing a program that makes a computer mounted on a mobile device function. Further, the flow of processing of these functional components can be understood as a method of determining the initial orientation of the portable device.

[Communication device 101]
The communication device 101 is for a scanner based on the BLE (or iBeacon®) short-range wireless standard. The communication device 101 receives a BLE beacon (Advertising Packet) from a plurality of tag devices arranged indoors. Then, the communication device 101 outputs the received beacon ID and the reception intensity to the first absolute positioning unit 11.

[Acceleration / angular velocity sensor 102]
The acceleration / angular velocity sensor 102 outputs the measured acceleration value and the angular velocity value to the relative positioning unit 12. The acceleration / angular velocity sensor 102 is for pedestrian autonomous navigation (PDR: Pedestrian Dead Reckoning).

[First absolute positioning unit 11]
The first absolute position positioning unit 11 positions the first absolute position using a communication device 101 that receives short-range radio waves from a plurality of other devices.
The first absolute positioning unit 11 stores the positions (floor maps) of the tag devices arranged indoors in advance. Then, the first absolute position positioning unit 11 estimates the first absolute position by a three-point survey method from the beacon IDs and reception intensities of the plurality of tag devices received from the communication device 101. The first absolute position is acquired in chronological order from the start of positioning together with the positioning time.

FIG. 2 is an explanatory diagram showing a time series of the first absolute position.

The first absolute position positioning unit 11 acquires the first absolute position of the portable device in chronological order from the start of positioning. For example, by measuring at predetermined time intervals, the first absolute position can be plotted in time series. However, since the first absolute position in the time series is estimated by the reception intensity of the BLE beacon, it is premised that an error is included.

[Relative positioning unit 12]
The relative position positioning unit 12 positions the relative position using an acceleration sensor and an angular velocity sensor.
The relative position positioning unit 12 acquires the relative position of the portable device in chronological order from the start of positioning. Specifically, the acceleration value and the angular velocity value are constantly received from the acceleration / angular velocity sensor 102. The relative position is acquired by detecting the "step" from the acceleration value and the "change in direction" from the angular velocity value as the displacement of the mobile terminal, and integrating them in combination.

[Second absolute positioning unit 13]
The second absolute positioning unit 13 presets a plurality of temporary initial directions. It is preferable to set the plurality of tentative initial directions so that the tentative initial directions are at equal angles to each other.

FIG. 3 is an explanatory diagram showing a plurality of tentative initial directions in the present invention.

According to FIG. 3, four tentative initial directions (0 °, 90 °, 180 °, 270 °) are set. As a specific embodiment, it is preferable to set, for example, 16 temporary initial directions at equal angles of 22.5 °.

FIG. 4 is an explanatory diagram showing a time series of the second absolute position in which the relative position is associated with the tentative initial direction.

The second absolute position positioning unit 13 associates the second absolute position from the time series of the relative position with the time series for each provisional initial direction from the start of positioning.
Here, according to the present invention, the relative positions from the absolute positions at the start of measurement are plotted in time series corresponding to each of the plurality of temporary initial directions. According to FIG. 4, when one relative position (displacement of the portable device) is measured, the second absolute position is plotted for each of the four tentative initial directions.

[Predetermined condition determination unit 14]
When the following conditions are satisfied, the predetermined condition determination unit 14 outputs a selection instruction to the initial direction selection unit 15.
(1) When a predetermined time is reached from the time of starting positioning, for example, 10 seconds may have passed from the start of positioning.
(2) When the relative positioning unit 12 or the second absolute positioning unit 13 reaches a predetermined distance from the positioning start position, for example, the predetermined distance is the cumulative travel distance and / or the linear distance from the positioning start position. It may be preset by.
This is an attempt to collect sufficient data so that the time series of the first absolute position and the time series of the second absolute position can be sufficiently compared.

FIG. 5 is an explanatory diagram showing a predetermined distance from the position where positioning starts.

According to FIG. 5, the second absolute position is taken as an example.
According to FIG. 5A, it represents the time when the cumulative movement distance from the positioning start position at the second absolute position reaches 10 m.
According to FIG. 5B, it represents the time when the linear distance of 10 m from the position where the positioning is started at the second absolute position is reached.
Further, it may be the time when both FIGS. 5 (a) and 5 (b) are achieved.
When these predetermined conditions are satisfied, the predetermined condition determination unit 14 outputs a selection instruction to the initial direction selection unit 15.

[Initial direction selection unit 15]
The initial direction selection unit 15 selects a time series of a plurality of second absolute positions to which a plurality of provisional initial directions are applied from the position of the start of positioning, which is most similar to the time series of the first absolute position. select.
Here, the initial direction selection unit 15 may select the initial direction when a selection instruction is input.

FIG. 6 is an explanatory diagram showing a comparison between a first absolute position and a plurality of second absolute positions.

The initial orientation selection unit 15 selects the one having the smallest mean square error as compared with the time series of the first absolute position among the time series of the plurality of second absolute positions. Specifically, the mean square error Err between the plots is calculated by comparing the plots of the plurality of second absolute positions based on substantially the same time with the plots of the first absolute position.
Err = 1 / n Σ _t ((H _t －A _t ) ² ) t = 0,1, ···, T
T: Time when the selection instruction is input from the predetermined condition determination unit 14.
n: Number of data at the position acquired between the measurement start time and the time when the selection instruction is input At: First absolute position at time t Ht: Second absolute position at time t And the mean square error Select the smallest second absolute position time series.

FIG. 7 is an explanatory diagram showing the determined initial orientation.

According to FIG. 7, the tentative initial direction in the time series of the selected second absolute position is selected as the initial direction. The initial direction is output to the hybrid positioning unit 16.

[Hybrid positioning unit 16]
The hybrid positioning unit 16 calculates the optimum position using the following information.
(1) First absolute position output from the first absolute position positioning unit 11 (2) Initial direction selected by the initial direction selection unit 15 (3) Relative position output from the relative position positioning unit 12

The hybrid positioning unit 16 outputs the first absolute position as a positioning result until the initial direction is selected.
After that, after the initial direction is selected, the hybrid positioning result using the first absolute position and the relative position is output based on the initial direction. That is, after the initial orientation is selected, the first absolute position and the relative position can be continuously input, and the hybrid positioning result can be continuously output.

As a specific hybrid positioning method, even if it is an existing one and, for example, as in Non-Patent Document 1 described above, the absolute position and the relative position are combined by a Kalman filter to determine the position with high accuracy. good.

As described above in detail, according to the portable device, the program and the method of the present invention, the initial direction of the relative position positioning can be estimated by using the absolute position positioning.

Various modifications, modifications and omissions of the above-mentioned various embodiments of the present invention within the scope of the technical idea and viewpoint of the present invention can be easily carried out by those skilled in the art. The above explanation is just an example and does not attempt to limit anything. The present invention is limited only to the scope of claims and their equivalents.

1 Mobile device 101 Communication device 102 Acceleration / angular velocity sensor 11 First absolute positioning unit 12 Relative positioning unit 13 Second absolute positioning unit 14 Predetermined condition determination unit 15 Initial direction selection unit 16 Hybrid positioning unit

Claims (9)

In mobile devices
From the start of positioning, the first absolute position positioning means for acquiring the first absolute position of the mobile device in chronological order, and
Relative positioning means that acquires the relative position of the mobile device in chronological order from the start of positioning,
A second absolute position positioning means that sets a plurality of temporary initial directions in advance and calculates a time series of a second absolute position from the time series of the relative positions for each temporary initial direction from the start of positioning.
With a predetermined condition determination means that outputs a selection instruction when a predetermined time from the positioning start time is reached or when a predetermined distance from the positioning start position is reached.
When the selection instruction is output, the time series most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute position is selected. A portable device comprising an initial direction selection means for selecting a tentative initial direction in a time series of positions as an initial direction. The portable device according to claim 1, wherein the plurality of provisional initial orientations are set so that the provisional initial orientations are set to have equal angles between the provisional initial orientations. The first absolute position positioning means positions the first absolute position using a communication device that receives short-range radio waves from a plurality of other devices.
The portable device according to claim 1 or 2, wherein the relative position positioning means measures a relative position using an acceleration sensor and an angular velocity sensor. The communication device receives BLE (Bluetooth Low Energy) or iBeacon (registered trademark) radio waves and uses them for positioning.
The portable device according to claim 3, wherein the accelerometer and the angular velocity sensor are for pedestrian autonomous navigation (PDR). Until the initial orientation is selected, the first absolute position output from the first absolute position positioning means is output as the positioning result.
After the initial orientation is selected, the first absolute position output from the first absolute positioning means and the output from the relative positioning means are output based on the initial orientation selected by the initial orientation selecting means. The portable device according to any one of claims 1 to 4, further comprising a hybrid positioning means for calculating an optimum position using the relative positions. The initial orientation selection means is characterized in that it selects the one having the smallest mean square error as compared with the time series of the first absolute position among the time series of the plurality of second absolute positions. The portable device according to any one of 1 to 5. The one according to any one of claims 1 to 6, wherein the predetermined distance in the predetermined condition determination means is a preset cumulative movement distance and / or a linear distance from a positioning start position. Portable device. In a program that makes a computer installed in a mobile device function
From the start of positioning, the first absolute position positioning means for acquiring the first absolute position of the mobile device in chronological order, and
Relative positioning means that acquires the relative position of the mobile device in chronological order from the start of positioning,
A second absolute position positioning means that sets a plurality of temporary initial directions in advance and calculates a time series of a second absolute position from the time series of the relative positions for each temporary initial direction from the start of positioning.
With a predetermined condition determination means that outputs a selection instruction when a predetermined time from the positioning start time is reached or when a predetermined distance from the positioning start position is reached.
When the selection instruction is output, the one most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute is selected. A program of a portable device characterized in that a computer functions as an initial direction selection means for selecting a temporary initial direction in a time series of positions as an initial direction. In the method of determining the initial orientation of a mobile device,
The portable device is
From the start of positioning, the first step of acquiring the first absolute position of the mobile device in chronological order, and
From the start of positioning, the second step of acquiring the relative position of the mobile device in chronological order,
A third step in which a plurality of temporary initial directions are set in advance and the time series of the second absolute position is calculated from the time series of the relative positions for each temporary initial direction from the start of positioning.
The fourth step of outputting the selection instruction when the predetermined time from the positioning start time is reached or when the predetermined distance from the positioning start position is reached.
When the selection instruction is output, the time series most similar to the time series of the first absolute position is selected from the time series of the plurality of second absolute positions, and the selected second absolute position is selected. A method for determining the initial orientation of a mobile device, which comprises performing a fifth step of selecting a tentative initial orientation in a time series of positions as an initial orientation.

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