Mobile body display device, mobile body display method, and mobile body display program

Abstract

A mobile body display device according to the present invention comprises: a position information acquisition unit that acquires one or more pieces of position information of a mobile body; a movement history storage unit that stores one or more movement histories of the mobile body; a route information generation unit that generates one or more pieces of route information from the movement histories; a position correction information generation unit that generates, from the position information, position correction information for correcting the position information; a position information correction unit that generates corrected position information by correcting the position information by using the route information and the position correction information; and a position information display unit that displays the corrected position information.

Description

MOBILE OBJECT DISPLAY DEVICE, MOBILE OBJECT DISPLAY METHOD, AND MOBILE OBJECT DISPLAY PROGRAM

[0001] The present invention relates to a mobile object display device, a mobile object display method, and a mobile object display program.

[0002] Satellite positioning systems, such as GPS, are widely used as a means for determining the position (latitude, longitude, and altitude) of a moving object on the ground in real time.

[0003] Mobile display devices are known that use satellite positioning systems to capture the location of a moving object and display it on a screen along with a route or course on a map. One example of such a mobile display device is a car navigation system. Mobile display devices are also used for watching bicycle, motorcycle, and car races.

[0004] In a satellite positioning system, a receiver receives radio waves transmitted from multiple communication satellites, and determines the receiver's two-dimensional or three-dimensional position by calculating the distance from each communication satellite using the difference between the transmission time and the reception time, the propagation speed of the radio waves, and the satellite's position (orbital information).

[0005] Such satellite positioning systems usually contain errors for several reasons. The first is when the transmitted time is inaccurate due to the precision of the clock on the communication satellite. The second is when the received radio waves are inaccurate due to diffraction or reflection. The third is when the radio waves cannot be received at all due to being absorbed or blocked by high-rise buildings or other structures.

[0006] To solve these problems, satellite positioning systems use multiple communication satellites to determine positioning, but because radio satellites are not geostationary, it is known that accuracy varies depending on the location, time, and environment. For this reason, it is necessary to take measures such as using an index value (position accuracy degradation rate) that indicates the satellite configuration status to exclude low-accuracy location information.

[0007] Map matching is a method for correcting location information of a moving object, which may contain errors, by comparing its movement history, which is the time transition of the location information, with route information to derive a plausible route. Route information is generally represented using a graph represented by nodes and edges.

[0008] For example, car navigation systems use geographic information, particularly road information such as road shapes, as route information and correct location information onto the road, thereby providing highly accurate services such as presenting a map of the surrounding area and providing route guidance to the destination.

[0009] Non-Patent Document 1 describes a map matching method that uses a hidden Markov model to match movement history with route information with high accuracy.

[0010] As map matching, in addition to the method disclosed in Non-Patent Document 1, various methods have been proposed, such as those using geometric analysis, topological analysis, and probabilistic methods.

[0011] Newson P., Krumm J., "Hidden Markov Map Matching Through Noise and Sparseness," Proceedings of the 17th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, Seattle, WA, 2009, pp. 336-343.

[0012] Map matching assumes that geographic information does not change frequently and corrects location information using predetermined static route information. In addition, car navigation systems only need to correct the vehicle's position on the road, so even if the accuracy of location information is on the order of meters, there are few service issues.

[0013] On the other hand, in a bicycle road race, for example, bicycles move to various locations on the road depending on the situation of the race, so predetermined static geographic information cannot be used as route information. Furthermore, conventional map matching corrects the position information of all bicycles to a reference position on the road (for example, the center of the road), so it is not possible to grasp situations such as when riders are racing side by side from the corrected position information.

[0014] The present invention has been made in light of the above-mentioned circumstances, and its purpose is to provide a moving object display device, a moving object display method, and a moving object display program that accurately correct and display the position information of a moving object.

[0015] One aspect of the present invention is a mobile object display device that displays the movement of one or more mobile objects. The mobile object display device includes a position information acquisition unit that acquires one or more pieces of position information of the mobile objects, a movement history storage unit that stores one or more movement histories of the mobile objects, a route information generation unit that generates one or more pieces of route information from the movement histories, a position correction information generation unit that generates position correction information for correcting the position information from the position information, a position information correction unit that corrects the position information using the route information and the position correction information to generate corrected position information, and a position information display unit that displays the corrected position information.

[0016] One aspect of the present invention is a moving object display method for displaying the movement of one or more moving objects, the moving object display method including the steps of acquiring one or more pieces of position information of the moving objects, retaining one or more movement histories of the moving objects, generating one or more pieces of route information from the movement histories, generating position correction information for correcting the position information from the position information, correcting the position information using the route information and the position correction information to generate corrected position information, and displaying the corrected position information.

[0017] One aspect of the present invention is a moving object display program that causes a computer to execute at least some of the functions of the components of the above-described moving object display device.

[0018] According to the present invention, there are provided a moving object display device, a moving object display method, and a moving object display program that accurately correct and display position information of a moving object.

[0019] FIG. 1 is a block diagram showing the functional configuration of a mobile object display device according to an embodiment. FIG. 2 is a diagram showing an example of a screen displayed on a position information display unit of a mobile object display device according to a first embodiment. FIG. 3 is a diagram showing an example of a graph of a travel path created by arranging positions at each time in a travel history on a two-dimensional plane in the first embodiment. FIG. 4 is a diagram showing how, in the first embodiment, the corrected position information approaches the position information on the route as the position correction information increases, and how, in the first embodiment, the corrected position information approaches the measured position information as the position correction information decreases. FIG. 5 is a diagram showing an example of a screen displayed on a position information display unit of a mobile object display device according to a second embodiment. FIG. 6 is a diagram showing each travel path calculated by arranging positions at each time in each travel history on a two-dimensional plane to derive a representative travel path in the second embodiment. FIG. 7 is a diagram showing intersections between each travel path calculated to derive a representative travel path and multiple line segments in the second embodiment. FIG. 8 is a diagram showing a representative travel path determined as a new travel history by arranging a set of representative positions of each cluster in the second embodiment. FIG. 9 is a diagram showing a representative travel path including tolerance range information. FIG. 10 is a diagram showing position information divided into clusters in order to obtain position information on a route in the second embodiment. FIG. 11 is a diagram showing a representative position obtained from position information included in a cluster in order to obtain position information on a route in the second embodiment. FIG. 12 is a diagram showing position information on a route obtained by matching a representative position with a moving route in the second embodiment. FIG. 13 is a diagram showing position accuracy for position information included in a cluster in the second embodiment. FIG. 14 is a diagram showing correction information for correcting position information on a route of a cluster in the second embodiment. FIG. 15 is a block diagram showing the hardware configuration of a mobile object display device according to an embodiment.

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0021] (Functional Configuration) First, the functional configuration of a mobile object display device 10 according to the embodiment will be described with reference to Fig. 1. Fig. 1 is a block diagram showing the functional configuration of a mobile object display device 10 according to the embodiment.

[0022] The mobile object display device 10 includes a position information acquisition unit 20, a movement history storage unit 30, a route information generation unit 40, a position correction information generation unit 50, a position information correction unit 60, and a position information display unit .

[0023] The position information acquisition unit 20 acquires position information of the moving object and outputs the acquired position information of the moving object to the movement history storage unit 30, the position correction information generation unit 50, and the position information correction unit 60.

[0024] The movement history storage unit 30 stores one or more movement histories for each moving object. The movement history is a collection of pairs of location information of the moving object and information on the time when the location information was acquired. In other words, the movement history storage unit 30 stores, as the movement history, a collection of pairs of location information of the moving object acquired by the location information acquisition unit 20 and information on the time when the location information was acquired.

[0025] When reproducing the movement of the moving object, as a preliminary preparation, the movement history storage unit 30 stores a past movement history in advance. The past movement history is, for example, a movement history stored by the movement history storage unit 30 before reproducing the movement of the moving object this time. Alternatively, the past movement history may be a movement history recorded by other means.

[0026] Furthermore, the movement history holding unit 30 holds, as a current movement history, a set of pairs of the position information of the moving object currently acquired by the position information acquiring unit 20 and the time information of the acquisition thereof, in order to reproduce the movement of the moving object.

[0027] The route information generating unit 40 generates one or more travel routes using one or more travel histories stored by the travel history storing unit 30, and stores a collection of the generated travel routes as route information. In one example, the travel route is a travel route of a moving object. In another example, the travel route is a representative travel route determined from multiple travel histories. Details of the travel route will be described later in the examples.

[0028] The position correction information generating unit 50 generates position correction information for correcting the position information from one or more pieces of position information. Details of the position correction information will be described later in the embodiment.

[0029] The position information correction unit 60 corrects the position information acquired by the position information acquisition unit 20 based on the route information held by the route information generation unit 40 and the position correction information generated by the position correction information generation unit 50, and generates corrected position information.

[0030] The position information display unit 70 displays on a screen the corrected position information generated by the position information correction unit 60. For example, the position information display unit 70 presents each piece of corrected position information in a 3D space, and reproduces and displays the movement of the moving object as time passes.

[0031] For example, the mobile display device 10 is a bicycle road race viewing system that continuously acquires bicycle position information and displays it as a movement history in a bicycle road race in which multiple bicycles compete.

[0032] The following describes an embodiment in which the mobile display device 10 is a bicycle road race viewing system. That is, the object of viewing by the mobile display device 10 is a bicycle road race, and the moving object of viewing is a bicycle.

[0033] (First embodiment) The mobile display device 10 according to this embodiment is an example of a bicycle road race viewing system that, in a bicycle road race in which multiple bicycles compete, acquires and displays the position information of a bicycle every moment and displays it as a movement history, thereby presenting the behavior of the bicycle in an easy-to-understand manner.

[0034] An example of a screen displayed on the position information display unit 70 of the mobile object display device 10 according to this embodiment is shown in Fig. 2. As shown in Fig. 2, a specific bicycle is dynamically displayed as an icon in 3D space on the screen of the position information display unit 70, and the behavior of the bicycle is expressed in an easy-to-understand manner.

[0035] In the following description, the viewing target of the mobile body display device 10 according to this embodiment is a specific bicycle. However, the viewing target of the mobile body display device 10 according to this embodiment is not limited to this, and may be a specific plurality of bicycles.

[0036] The operation of each unit in the mobile object display device 10 according to this embodiment will be described below.

[0037] First, the location information acquisition unit 20 acquires location information p(i, t) from a satellite positioning system using a receiver such as a GPS logger attached to the bicycle, where i represents a certain bicycle i and t represents the time t when the positioning was performed.

[0038] The location information p(i, t) includes, but is not limited to, the bicycle's position (latitude, longitude, altitude) obtained from the satellite positioning system, an index value indicating its accuracy (such as the rate of decrease in position accuracy), and the bicycle's acceleration and direction obtained by the receiver.

[0039] The movement history storage unit 30 stores one or more movement histories h(j, n) in advance. The movement history h(j, n) is a time t ０ From t ｎ A set S of location information of bicycle j at each time up to ｐ (j, n) = (p(j, t ０ ), p(j,t １ ), ..., p(j, t ｎ )).

[0040] In the case of bicycle road races targeted by the mobile object display device 10 according to this embodiment, the movement history h(j, n) refers to the movement history of multiple bicycles, multiple laps, and multiple events previously acquired in races on the same course. The value of n generally differs for each bicycle j. Since the traveling speed of each bicycle participating in a race differs, if the bicycle position is acquired at regular time intervals, the value of n will change depending on the speed in the movement history for one lap of the course. Of course, in some cases, n may be a fixed value, i.e., only movement history within a certain period of time may be used.

[0041] Also, the start time of the meeting is t ０Instead, for example, only a specific section where a large error in the position information is expected due to the shadow of a building may be used as the movement history. In this case, the mobile object display device 10 corrects the position information only for that section and uses the position information for other sections as is to represent the behavior of the bicycle.

[0042] If the race has not yet been held, movement history may be obtained by prior practice runs, etc. Furthermore, movement history does not necessarily have to rely on location information obtained by a satellite positioning system. Images may be obtained from onboard cameras on motorcycles accompanying bicycles or fixed cameras installed around the course, and movement history may be obtained using existing object position estimation technology. However, in the case of road races, motorcycles are not always present accompanying all bicycles, so it is difficult to obtain movement history for all bicycles participating in the race. Furthermore, because road race courses are several kilometers long, it is generally difficult to install fixed cameras at every position along the course.

[0043] When using location information from a satellite positioning system, there is a possibility that it may contain errors, so it is desirable to correct it manually in advance.

[0044] Furthermore, the movement history storage unit 30 stores the time t ０ From t ｎ Set S of location information at each time up to ｐ (i, n) = (p(i, t ０ ), p(i,t １ ), ..., p(i, t ｎ )) is stored as a movement history h(i, n).

[0045] Next, the route information generation unit 40 generates a travel route r(j) on the course for bicycle j using one or more travel histories, and stores the set R = (r(0), r(1), ..., r(l)) of these routes as route information, where l indicates the total number of bicycles whose travel histories have been acquired.

[0046] The travel route r(j) is the travel history h(j, n) of bicycle j at time t ｍ Position p(j, t) at (0≦m≦n) ｍ) on a two-dimensional plane or in a three-dimensional space with elevation differences using geographic information, and ｍ ) as nodes and connect them with edges. Figure 3 shows an example of a graph of travel routes created by arranging the positions at each time in the travel history on a two-dimensional plane. In Figure 3, as an example, the travel routes of two bicycles are shown by a solid line (r(0)) and a dotted line (r(1)).

[0047] Next, the position correction information generator 50 generates position correction information c(i, t) for correcting the position information from one or more pieces of position information p(i, t). In this embodiment, the position correction information is generated using the positional dilution of precision (PDOP) acquired by the satellite positioning system. The PDOP is one of the indices related to the geometric arrangement of the satellite constellation used for positioning, and the smaller the value, the higher the measurement accuracy. Since the PDOP value is calculated each time positioning is performed, in this embodiment, the position correction information c(i, t) is the positional dilution of precision d(i, t) of the position information p(i, t).

[0048] The position correction information c(i, t) does not need to be the position accuracy degradation rate. Instead of the position accuracy degradation rate, the position correction information c(i, t) may be, for example, the position information p(i, t-1) estimated using a Kalman filter or the like. ｋ Position correction information c (i, t) represents the degree of deviation between the position information p(i, t) and the position information p(i, t), i.e., the degree of deviation between the estimated position based on the position information and the geometric position measured by the satellite positioning system. ｋ (i, t) may be used. In this case, for example, ｋ (i, t) is expressed by the right side of the following equation (1), and p ｋ Position correction information c whose value increases as the distance between (i, t) and p(i, t) increases ｋ (i, t) is obtained.

[0049]

[0050] Next, the position information correction unit 60 corrects the position information p(i,t) of the bicycle i using the route information R, the movement history h(i,n-1), and the position correction information c(i,t). First, the position information correction unit 60 uses map matching to derive the position information p(i,t) on the route from the route information R, the position information p(i,t), and the movement history h(i,n-1). Ｒ For example, the closest route information r(j) is calculated using the method described in Non-Patent Document 1, and the intersection point with the perpendicular line from p(i,t) is calculated as p(i,t). Ｒ The position information correction unit 60 calculates the position information p(i, t) and the position information p Ｒ (i, t), and the position correction information c(i, t) are used to obtain the corrected position information p ｃ (i, t) is calculated using the following equation (2). ｄ means a constant value that is predetermined to determine the reliability of the position correction information.

[0051]

[0052] According to the above formula (2), the larger the position correction information c(i, t), that is, the larger the error in the position measured by the satellite positioning system, the larger the corrected position information p ｃ (i, t) is the position information p Ｒ On the other hand, the smaller the position correction information c(i, t), that is, the smaller the error in the position measured by the satellite positioning system, the more reliable the measurement value becomes. ｃ (i, t) is close to the measured position information p(i, t) (FIG. 4).

[0053] In this embodiment, the corrected position information p ｃ The above formula was used to calculate (i, t), but the corrected position information p(i, t) is calculated using the position information p(i, t), movement history h(i, n-1), and position correction information c(i, t). ｃ There are no particular restrictions on the method for determining (i, t).

[0054] Next, the position information display unit 70 displays the corrected position information p on a 3D space reproduced using a 3D city model such as PLATEAU. ｃ By presenting (i, t), the system reproduces and displays how the bicycle moves as time t changes. PLATEAU is a project led by the Ministry of Land, Infrastructure, Transport and Tourism to create 3D city model facilities across Japan and make the data open.

[0055] By using the mobile object display device 10 according to the present embodiment, when correcting location information containing errors using route information, map matching can be used to select a close route from one or more pieces of route information generated from a collection of past travel histories, thereby correcting the location information to various travel routes without using static geographic information as route information. Furthermore, by acquiring location correction information from one or more pieces of location information and correcting the location information, the location information can be corrected to an appropriate position depending on, for example, the reliability of the location information.

[0056] (Second Example) The mobile display device 10 according to this example is an example of a bicycle road race viewing system that acquires and displays the position information of multiple bicycles in real time in a bicycle road race in which multiple bicycles compete, and displays this information as a movement history, thereby clearly presenting the behavior of individual bicycles and the situation in which bicycles compete against each other.

[0057] An example of a screen displayed on the position information display unit 70 of the mobile object display device 10 according to this embodiment is shown in Fig. 5. As shown in Fig. 5, multiple bicycles are dynamically displayed as icons in a 3D space on the screen of the position information display unit 70, and the behavior of individual bicycles and the state of competition between them are clearly displayed.

[0058] The operation of each unit in the mobile object display device 10 according to this embodiment will be described below.

[0059] First, the position information acquisition unit 20 acquires position information p(i, t) from a satellite positioning system using a receiver such as a GPS logger attached to the bicycle.

[0060] The difference from the first embodiment is that in this embodiment, position information p(i, t) (0≦i≦l) is obtained not only for a specific bicycle i, but also for all l bicycles participating in the race.

[0061] Next, the movement history holding unit 30 holds one or more movement histories h(j, n) in advance, as in the first embodiment. The movement history h(j, n) is ０ From t ｎ A set S of location information of bicycle j at each time up to ｐ (j, n) = (p(j, t ０ ), p(j,t １ ), ..., p(j, t ｎ )).

[0062] Furthermore, the movement history storage unit 30 stores the time t ０ From t ｎ Set S of location information at each time up to ｐ (i, n) = (p(i, t ０ ), p(i,t １ ), ..., p(i, t ｎ )) are stored as movement histories h(i, n).

[0063] Next, the route information generation unit 40 generates a representative route r(j') on the course using one or more travel histories h(j, n), and stores the set R = (r(0), r(1), ..., r(l')) of these routes as route information, where l' indicates the total number of travel histories created.

[0064] Unlike the first embodiment, in this embodiment, by combining multiple movement histories h(j, n), l' (l'≦l") representative movement routes r(j') are obtained from l" (l"≦l) movement histories h(j, n).

[0065] In this embodiment, the method for determining the representative travel route r(j') is to determine the intersections between each travel route r(j) determined from each travel history h(j,n) by the method of the first embodiment and a course divided into a certain number of sections, and then to determine l' representative travel routes r(j') by clustering these intersections.

[0066] The procedure for deriving the representative movement route r(j') will be described below with reference to FIGS.

[0067] First, on a two-dimensional plane for which a travel path is to be determined, a plurality of line segments L(x) are drawn to divide the plane. The intervals at which the line segments are drawn do not need to be constant; for example, the intervals may be varied by referring to geographical information, such as drawing the line segments more closely around curves, which tend to complicate travel paths. Furthermore, when using a three-dimensional space, the space may be divided using planes instead of line segments. In this embodiment, a two-dimensional plane is used to make the explanation easier to understand.

[0068] Next, the positions at each time of each movement history h(j,n) are arranged on a two-dimensional plane to obtain each movement path r(j) (Fig. 6). Next, the intersections p(j,x) between each movement path r(j) and multiple line segments L(x) are obtained (Fig. 7). Next, the multiple intersections p(j,x) on each line segment L(x) are clustered using the k-means method or the like, and the representative position p(j,x) of each cluster c(j',x) is obtained. ｃ (j', x) are calculated, and a set of these is used as a new movement history h(j', n) to determine a representative movement route r(j') (FIG. 8).

[0069] Representative position p ｃ For example, the average value of the coordinates of each intersection p(j, x) included in the cluster may be used as (j', x). Alternatively, the representative position p(j, x) may be determined by weighting p(j, x) using the PDOPs of two points before and after the intersection p(j, x) in the movement history used to determine the intersection p(j, x). ｃ (j', x) may be calculated by using a method other than the method described here. ｃ In this embodiment, the average value of the former coordinates is used as the representative position p ｃ Used for (j', x).

[0070] When determining the representative movement path r(j'), ｃ (j', x) is a set of multiple p ｃ Regarding which of (j', x+1) is connected, for example, when the vertical direction of the schematic diagrams of FIGS. 6 to 8 is the y axis, the p ｃ (j', x) and p ｃThere is a method of adopting (j', x+1) as the movement history h(j', n).

[0071] In this embodiment, when there are multiple connection candidate clusters c(j', x+1) for a certain cluster c(j', x), the connection candidate cluster c(j', x+1) that contains the most p(j, x+1) connected to each intersection p(j, x) in c(j', x) is selected as the connection destination, and its representative position p ｃ (j', x) is adopted as the movement history h(j', n), and the route connecting them is taken as the representative movement route r(j').

[0072] In this embodiment, the clustering method, representative position determination method, and movement history selection method described above are used, but other methods may also be used to determine the l' representative movement routes r(j').

[0073] Furthermore, in this embodiment, the route information generating unit 40 generates tolerance range information t(j') indicating the tolerance range of the representative route r(j'), and stores the tolerance range information t(j') as the representative route r(j'). FIG. 9 is a schematic diagram showing a representative route including tolerance range information. In FIG. 9, the range expressed in gradation along the representative route r(j') represents the tolerance range information t(j').

[0074] Here, each representative position p ｃ In (j', x), a Gaussian distribution g(j', x) is calculated from each intersection p(j, x) in the cluster c(j', x) used to calculate the representative position, and the tolerance t(j', x, x') between each intersection is calculated using the following formula (3), and the set of these is used as the tolerance range information t(j'). Here, l(j, x) is the representative position p ｃ (j', x) and representative position p ｃ (j', x+1), and x' is the distance between the representative position p ｃ (j', x) and representative position p ｃ Representative position p on the line segment connecting (j', x+1) ｃ (j', x). According to formula (3), the tolerance information t(j') is calculated by dividing the Gaussian distribution g(j', x) at each point by the representative position p ｃIt is calculated as a value obtained by linearly interpolating between (j', x).

[0075]

[0076] Since the representative movement route r(j') is obtained from multiple movement routes r(j), the actual bicycle does not necessarily have to be at the representative position p ｃ (j', x) will not necessarily move along the representative travel route r(j') connecting the bicycles. The allowable range information t(j') is information indicating how far the actual bicycle can move from the representative travel route r(j'). In this embodiment, the allowable range information t(j') is calculated using the method described above, but the allowable range information t(j') may also be calculated using a method other than the method described here, such as calculating the allowable range information t(j) for each of the multiple travel routes r(j) used when calculating the representative travel route r(j') and standardizing them to obtain the allowable range information t(j').

[0077] In this embodiment, the reason for determining l' representative movement paths r(j') is that when there is a large number of movement histories h(j,n), determining a movement path r(j) from each movement history individually results in a dense network of paths, increasing the amount of map matching processing and making it difficult to select an appropriate path. In road races, for example, there may be biases in movement paths, such as a tendency to choose the outside-in-out at corners, a tendency to run on the left or right side rather than the center on wide roads to avoid being overtaken by following runners, and avoiding slippery areas such as manholes. By determining a representative movement path from multiple movement paths using such biases, as in this embodiment, map matching becomes easier.

[0078] Next, the position correction information generating unit 50 generates position correction information c(i, t) for correcting the position information from one or more pieces of position information p(i, t) acquired by the position information acquiring unit 20 .

[0079] In this embodiment, first, the position information p(i, t) is clustered to obtain a representative position p ｐ (i', t) is calculated, and the representative position p ｐ(i', t) is matched with the l' representative movement routes r(j') generated by the route information generating unit 40, and the position information p Ｒ (i', t) is obtained.

[0080] 10 to 14, the position information p Ｒ The procedure for obtaining (i', t) will be explained.

[0081] First, the location information p(i, t) at a certain time t is divided into clusters c using the k-means method or the like. ｐ (i', t) (Fig. 10). Next, for each cluster c ｐ From the position information p(i, t) contained in (i', t), the representative position p ｐ (i', t) is calculated (Fig. 11). ｐ There are various methods for obtaining (i', t), including the above-mentioned method. In this embodiment, as described in relation to the route information generating unit 40, the average value of the coordinates of each piece of position information p(i, t) is calculated as the representative position p ｐ Next, let (i', t) be the representative position p ｐ (i', t) and the position information p Ｒ (i', t) is obtained (FIG. 12).

[0082] In this embodiment, the representative position p ｐ As a method for finding the representative path r(j') that is geometrically closest to (i', t), the representative path r(j') that includes the path with the shortest perpendicular line extended to the edge of the representative path r(j') is selected as the path, and the intersection of the edge and the perpendicular line is calculated as position information p Ｒ Let (i', t).

[0083] In this embodiment, the above method is used to obtain the position information p Ｒ (i', t), but using other methods to obtain position information p Ｒ For example, each cluster c at time t-1 already derived by this procedure may be obtained. ｐ The cluster c that is geometrically close to (i', t-1) ｐ (i', t-1) is selected and its representative position p ｐ(i', t-1) is found, and the representative positions p ｐ (i', t-2), p ｐ (i', t-3), ... to obtain the position information p Ｒ By using (i', t) as the movement history and performing map matching using the method shown in Non-Patent Document 1, position information p Ｒ (i', t) may be obtained.

[0084] Next, for each cluster c ｐ For the position information p(i,t) included in (i',t), a position accuracy a(i,t) indicating the accuracy of the position information is calculated (FIG. 13). As mentioned above, since the position information p(i,t) may contain errors, the correct position may exist within a certain range centered on the position information p(i,t). In this embodiment, the position accuracy a(i,t) is calculated with a mean μ=0 and a variance σ ２ A Gaussian distribution with values ​​shown in the following formula 4 is used for C σ is a predetermined constant value that controls the degree of dispersion, and PDOP(i,t) refers to the PDOP value of the position information p(i,t). The larger the PDOP value, i.e., the lower the position accuracy, the wider the base of the Gaussian distribution, so the position accuracy a(i,t) indicates that the position information is ambiguous, with the position information p(i,t) at its center. Conversely, the smaller the PDOP value, the narrower the base of the Gaussian distribution, so the position accuracy a(i,t) indicates that the position information p(i,t) has a high degree of accuracy.

[0085]

[0086] In this embodiment, the PDOP value and Gaussian distribution are used, but the position accuracy a(i, t) may be calculated using other values ​​and derivation formulas that express the accuracy of the position information.

[0087] Next, the allowable range information t(j') is multiplied by each position accuracy a(i, t) using the following equation (5) to obtain the maximum position correction information c(i, t) (FIG. 14). Here, A(a, c) is a function that translates the center coordinate of the position accuracy a by the coordinate value of c, and Lc is a predetermined constant that restricts the range of movement.

[0088]

[0089] In order to clearly show the above, in FIG. 14, cluster c ｐ Position information p on the route of (i', t) Ｒ By showing the state where (i', t) is corrected by c(i, t), the cluster c ｐ 14, the position accuracy a(i, t) included in (i', t) has been corrected as a whole. As shown in Fig. 14, the position correction information c(i, t) is the value obtained by correcting the position to the location where the product of the allowable range information t(j') and the position accuracy a(i, t) is high, that is, the location where the set of bicycles included in the cluster is most likely to be located within the allowable range in which bicycles can move along the representative movement route r(j').

[0090] In this embodiment, the position correction information c(i,t) is calculated using the above formula (5). However, other methods may be used to calculate the position correction information c(i,t) as long as they can correct the position to a highly accurate position using each position accuracy a(i,t) for the allowable range information t(j'). For example, c(i,t) may include rotation rather than translation of coordinates. Furthermore, each piece of position correction information c(i,t) may be calculated using the allowable range information t(j') to adjust the relative position of each position accuracy a(i,t) to achieve the most accurate position.

[0091] In this embodiment, the reason for calculating the position correction information c(i, t) is that in road races, riders tend to group together to reduce wind resistance and conserve their energy, and because the accuracy of position information is easily affected by the position of communication satellites and the surrounding environment, bicycles in similar positions are likely to contain similar errors. By dividing multiple pieces of position information p(i, t) into clusters and correcting each cluster to the most accurate position within the allowable range, it is possible to perform position corrections in road races that are more likely than correcting each individual position.

[0092] Next, the position information correction unit 60 corrects the position information p(i, t) of the bicycle i using the route information R, the movement history h(i, n-1), and the position correction information c(i, t). ｐ Since the position correction information c(i', t) is obtained in units of (i', t), the corrected position information p ｃ (i, t) can be obtained using the following equation (6): where Ac(a, c) is a function that translates the coordinates of the position information a by the coordinate value of c.

[0093]

[0094] The location information p(i, t) is cluster c ｐ If it is included in (i', t), then cluster c ｐ The position correction information c(i', t) obtained in (i', t) is used to translate the position information p(i, t) to obtain the corrected position information p ｃ (i, t) is found.

[0095] Next, the position information display unit 70 displays each corrected position information p on a 3D space reproduced using a 3D city model such as PLATEAU. ｃ By presenting (i, t), the movement of each bicycle is reproduced and displayed as time t changes.

[0096] By using the mobile object display device 10 of this embodiment, when correcting position information containing errors using route information, a collection of past movement history is combined to generate a representative movement route that includes the range in which the bicycle can move, and the accuracy of the position is calculated on a group basis from one or more position information, and the position with the highest accuracy within the range in which the bicycle can move is obtained as position correction information and the position information is corrected, thereby making it possible to correct the bicycle's position information more plausibly by using the characteristics of satellite positioning systems and road races.

[0097] (Effects) The moving object display device 10 according to the embodiment determines a moving route using one or more movement histories collected in advance, and corrects the position information using one or more pieces of position information, thereby reproducing the plausible movement of the moving object even when the position information contains an error.

[0098] According to the mobile body display device 10 of the embodiment, when correcting location information containing errors using route information, in cases such as bicycle races where static geographical information cannot be used as route information and the location information cannot be corrected directly on the route, route information is determined using one or more movement histories and the location information is corrected using multiple pieces of location information, thereby making it possible to correct the bicycle's location information more plausibly by using the characteristics of satellite positioning systems and road races.

[0099] (Hardware Configuration) Next, a hardware configuration of the mobile object display device 10 will be described. Here, an example will be described in which the mobile object display device 10 is configured as a computer. For example, the mobile object display device 10 may be configured as a personal computer, a server computer, or the like.

[0100] 15 is a block diagram showing an example of the hardware configuration of the mobile object display device 10 according to the embodiment, in other words, the hardware configuration of the computer 100 that constitutes the mobile object display device 10. The mobile object display device 10 (computer 100) has a control device 120, an input device 140, and an output device 150.

[0101] The control device 120 controls the entire mobile object display device 10. The control device 120 includes a processor 121, a read only memory (ROM) 122, a random access memory (RAM) 123, and an auxiliary storage device .

[0102] The processor 121, ROM 122, RAM 123, auxiliary storage device 124, input device 140, and output device 150 are electrically connected to one another via a bus 130, and can transmit and receive data.

[0103] The processor 121 is configured by a general-purpose hardware processor including, for example, a CPU (Central Processing Unit), a GPU (Graphical Processing Unit), etc. The processor 121 executes various functions of the mobile display device 10 by executing programs deployed in the RAM 123.

[0104] The ROM 122 is a non-volatile memory that constitutes part of the main storage device. The ROM 122 non-temporarily stores a startup program required to start up the mobile display device 10. The processor 121 loads the startup program in the ROM 122 into the RAM 123 and executes it to start up the mobile display device 10. The ROM 122 is configured, for example, with an EPROM (Erasable Programmable Read Only Memory), and is capable of storing various settings at startup in addition to the startup program.

[0105] The RAM 123 is a volatile memory that constitutes part of the main storage device. The RAM 123 temporarily stores programs required for processing by the processor 121 and data required for executing the programs. In other words, the RAM 123 functions as a work area for the processor 121.

[0106] The auxiliary storage device 124 is configured with non-volatile memory such as a hard disk drive (HDD) or a solid state drive (SSD). The auxiliary storage device 124 can non-temporarily store various programs executed by the processor 121 and data required for executing the programs. The processor 121 executes various functions of the mobile display device 10 by expanding the programs in the auxiliary storage device 124 into the RAM 123 and executing them.

[0107] The input device 140 is a device for a user to input information and instructions, and accepts input of information and instructions. The input device 140 includes a keyboard, a pointing device, etc. The pointing device includes a mouse, a trackpad, a touch screen, etc.

[0108] The output device 150 is a device that outputs information to provide information to a user. The output device 150 is, for example, a display device that displays characters, images, etc. on a screen. For example, the output device 150 is a liquid crystal display, an organic EL display, a plasma display, etc.

[0109] The output device 150 and the input device 140 may be configured as an input / output device having the functions of both. Such an input / output device may be configured as, for example, a touch panel.

[0110] The input device 140 may also include a device that inputs information or data from the outside. For example, the input device 140 may include a wired or wireless interface or receiving device.

[0111] The output device 150 may also include a device that outputs information or data to the outside. For example, the output device 150 may include a wired or wireless interface or transmission device.

[0112] The input device 140 may also include a device that reads data from a computer-readable recording medium 160 that non-temporarily records data such as a program. For example, the recording medium 160 includes disks such as flexible disks, optical disks (CD-ROM, CD-R, DVD-ROM, DVD-R, etc.), magneto-optical disks (MO, etc.), semiconductor memories, etc. The input device 140 includes drives, readers, etc. for these.

[0113] The program stored in the auxiliary storage device 124 is provided to the mobile display device 10, for example, via the recording medium 160. The program may also be stored in a server on a network and provided to the mobile display device 10 by downloading it.

[0114] For example, when the mobile display device 10 is started up, the processor 121 executes a startup program in the ROM 122 to start up the operating system (OS). Under the control of the OS, the processor 121 monitors input instructions, connections to external devices, etc. Also, under the control of the OS, the processor 121 sets a program area and a data area in the RAM 123.

[0115] In response to an instruction to start a program, processor 121 reads the program from auxiliary storage device 124 into the program area of ​​RAM 123, and also reads data necessary for executing the program from auxiliary storage device 124 into the data area of ​​RAM 123. Processor 121 calculates the data in the data area in accordance with the program and writes the calculation results into the data area.

[0116] Through these operations, the processor 121, RAM 123, and auxiliary storage device 124 work together to execute at least a portion of the functions of the control device 120. Furthermore, the control device 120, input device 140, and output device 150 work together to execute at least a portion of the functions of the mobile display device 10.

[0117] The programs non-temporarily stored in the auxiliary storage device 124 include a moving object display program that causes the processor 121 to execute at least some of the functions of the control device 120. In other words, the processor 121 executes this moving object display program to execute at least some of the functions of the control device 120.

[0118] As a result, the control device 120 works in cooperation with the input device 140 and the output device 150 to perform at least some of the functions of the location information acquisition unit 20, the movement history storage unit 30, the route information generation unit 40, the location correction information generation unit 50, the location information correction unit 60, and the location information display unit 70.

[0119] (Other) Embodiments of the present invention have been described above with reference to the drawings. However, the above embodiment is merely an example of a configuration that embodies the present invention. In other words, it is clear that the present invention is not limited to the above embodiment. Therefore, additions, omissions, substitutions, and other modifications of components may be made within the scope of the technical concept of the present invention.

[0120] In short, the present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

[0121] DESCRIPTION OF SYMBOLS 10... Mobile object display device 20... Position information acquisition unit 30... Movement history storage unit 40... Route information generation unit 50... Position correction information generation unit 60... Position information correction unit 70... Position information display unit 100... Computer 120... Control device 121... Processor 122... ROM 123... RAM 124... Auxiliary storage device 130... Bus 140... Input device 150... Output device 160... Recording medium

Claims

1. A mobile object display device that displays the movement of one or more mobile objects, comprising: a location information acquisition unit that acquires one or more pieces of location information of the mobile objects; a movement history storage unit that stores one or more movement histories of the mobile objects; a route information generation unit that generates one or more pieces of route information from the movement histories; a position correction information generation unit that generates position correction information from the location information to correct the location information; a location information correction unit that corrects the location information using the path information and the position correction information to generate corrected location information; and a location information display unit that displays the corrected location information.

2. A mobile object display device as described in claim 1, wherein the position information acquisition unit acquires position information of a specific mobile object, the movement history storage unit stores the movement history of the specific mobile object, the route information generation unit determines a movement route from the movement history of the specific mobile object and generates a collection of the movement routes as the route information, and the position information display unit displays the corrected position information of the specific mobile object generated by the position information correction unit in 3D space.

3. The mobile display device according to claim 2, wherein the position correction information generation unit generates the position accuracy degradation rate of the position information as the position correction information, and the position information correction unit generates the corrected position information using the position accuracy degradation rate.

4. A mobile body display device as described in claim 1, wherein the position information acquisition unit acquires position information of multiple mobile bodies, the movement history storage unit stores multiple movement histories of the multiple mobile bodies, the route information generation unit determines one or more representative movement routes from the multiple movement histories of the multiple mobile bodies and generates a collection of the representative movement routes as the route information, and the position information display unit simultaneously displays the corrected position information of the multiple mobile bodies generated by the position information correction unit in 3D space.

5. A mobile body display device as described in claim 4, wherein the route information generation unit generates tolerance range information indicating a tolerance range for the representative travel route for the representative travel route, and generates the representative travel route including the tolerance range information; the position correction information generation unit divides the position information of the multiple moving bodies into clusters, determines a representative position for each cluster, matches the representative position to the representative travel route to determine position information on the representative travel route, determines a position accuracy indicating the accuracy of the position information for the position information included in each cluster, and generates the maximum value of the product of the tolerance range information and the position accuracy as the position correction information.

6. The mobile display device according to claim 5, wherein, when the position information is included in the cluster, the position information correction unit generates the corrected position information by translating the position information.

7. A method for displaying the movement of one or more moving objects, comprising the steps of: acquiring one or more pieces of position information for the moving objects; retaining one or more movement histories for the moving objects; generating one or more pieces of route information from the movement histories; generating position correction information for correcting the position information from the position information; correcting the position information using the route information and the position correction information to generate corrected position information; and displaying the corrected position information.

8. A moving object display program that causes a computer to execute at least part of the functions of the components of the moving object display device according to claim 1.

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