JP5511905B2 - Navigation server and navigation system - Google Patents

Description

  The present invention relates to a navigation server that supports guidance by a navigation device based on communication with the navigation device.

In order to estimate the movement cost in the target road section, a technique using a search result of a time change pattern of the movement cost in the past time zone similar to the time change pattern of the movement cost in the current time zone has been proposed (Patent Document 1). reference). Further, a technique has been proposed that uses a standard time-varying pattern of accumulated traffic volume in a road section in order to estimate a movement cost in a road section where a contingency such as temporary closure has occurred (Patent Document 2). reference).
Japanese Patent No. 3888985 Japanese Patent No. 4678695

  However, the time change pattern such as the movement cost may vary according to differences in various factors such as the type and degree of the event that the user who passes through the same link or road section contacts. For this reason, there is a possibility that the estimation accuracy of the movement cost in each road section and the accumulated movement cost to the destination point may be lowered.

  In view of the above, an object of the present invention is to provide a navigation server and a navigation system that can further improve the estimation accuracy when estimating a traffic state variable value such as a movement cost in each link.

  The navigation server of the present invention recognizes the traffic condition variable value in each link constituting the road network and the temporal change pattern of the environmental factor that influences the traffic condition, and then the temporal change of the environmental factor with respect to the first related period. A first server arithmetic processing element configured to recognize a second related period of the same width that has a pattern similarity equal to or greater than a first reference value and before the first related period; and the first server Of the time change pattern of the traffic state variable value recognized up to the current time point recognized by the arithmetic processing element, the time change pattern of the traffic state variable value in the second period of the same width after the second related period for the specified period. The traffic state variable value after the end of the first period of the same width after the specified period and after the current time point is estimated based on the first related period in each link. Characterized in that it comprises a second server arithmetic processing element are, the.

  In the navigation server of the present invention, the first server computation processing element has a similarity of the time change pattern of the traffic state variable value with respect to the first period equal to or greater than a second reference value, and before the first period. It is preferable that a period of the same width is recognized as the second period.

  In the navigation server according to the present invention, the second server computation processing element is configured so that the link in the period after the end of the first period in each link is based on the time change pattern of the environmental factor in the period after the end of the first related period. It is preferable that the time change pattern of the traffic state variable value is estimated.

  In the navigation server of the present invention, the second server calculation processing element is based on a deviation of a time change pattern of the environmental factor in a period after the end of the first related period with respect to a period after the end of the second related period. The time change pattern of the traffic state variable value after the end of one period and after the current time point is corrected, and based on the time change pattern of the traffic state variable value after the correction and after the end of the first period in each link and the present It is preferable that the traffic state variable value after the time point is estimated.

  In the navigation server of the present invention, the first server calculation processing element recognizes a predictable first type environmental factor among the environmental factors in a future period after the current time point based on communication with the first external device. Based on the communication with the second external device, the second type environmental factor that is unpredictable among the environmental factors in the past period after the end of the second related period and before the current time point, or the first and second type environments It is preferably configured to recognize the factor.

  In the navigation server according to the present invention, the first server computation processing element recognizes the target designated link from the road network based on the communication with the navigation device, and then the current point in the designated link up to the current time point. The second server computation processing element is configured to recognize a temporal change pattern of a traffic state variable value, and the second server computation processing element is configured to receive a current period after the end of a first period of the same width after the specified period from the first related period in the specified link. It is preferable that the traffic state variable value after the time point is estimated, and based on communication with the navigation device, the navigation device is made to recognize the estimation result or designated traffic information based on the estimation result.

  The navigation system of the present invention includes the navigation server and the navigation device, and the first server computation processing element is based on communication with the navigation device, and the traffic state variable up to the current time point in each link. It is comprised so that the time change pattern of each of a value or the said traffic state variable value and the said environmental factor may be recognized.

  According to the navigation server of the present invention and the navigation system having this as a component, in view of the similarity of the temporal change pattern of environmental factors that affect the traffic state in each link, the traffic state variable value of an appropriate time zone The time change pattern is recognized as the basis for estimating the traffic state variable values after the current time. Thereby, the further improvement of the estimation precision of a traffic state variable value is achieved.

The navigation system of this invention, and the structure explanatory drawing of the navigation server which is the component, and a navigation apparatus. Functional explanatory drawing of the navigation server of this invention. Explanatory drawing regarding the search result of a server route. Explanatory drawing regarding the search of a 2nd related period. Explanatory drawing regarding the estimation method of movement cost.

(Constitution)
The navigation system shown in FIG. 1 includes a plurality of navigation devices 200 and a navigation server 100 having a communication function with each navigation device 200. The navigation server 100 includes a server storage element 104, a first server arithmetic processing element 110, and a second server arithmetic processing element 120.

  The server storage element 104 includes a storage device such as a memory, and is configured to store server map information including a road network arrangement mode. The server storage element 104 stores the movement cost pattern τ (i, t) and the environmental factor pattern γ (i, t) in each link L (i) (i = 1, 2,... N) constituting the road network. It is configured to store in association.

  The movement cost pattern τ (i, t) is a time change pattern of the movement cost τ (i) as a traffic state variable value. The environmental factor pattern γ (i, t) is a temporal change pattern of the environmental factor γ (i) that affects the traffic state.

  The environmental factor γ (i) includes a predictable “first type environmental factor” such as weather conditions such as climate, rainfall, snowfall, outside temperature or outside humidity, road construction or traffic regulation, “Type 2 environmental factors” that are unpredictable (or difficult to predict), such as the occurrence of an accident, are included. The environmental factor γ (i) is described by a variable value. When the environmental factor γ (i) is a state quantity, it is described by a continuous numerical value. When the environmental factor γ (i) is the presence or absence of an event, discrete numerical values such as “1” and “0” are used. Is described by

  The first type and second type environmental factors may not be distinguished. The environmental factor γ (i) may be composed of only one of the first type and second type environmental factors.

  The 1st server arithmetic processing element 110 and the 2nd server arithmetic processing element 120 are comprised so that the below-mentioned arithmetic processing may be performed. “Constructed” means that the arithmetic processing element executes the assigned arithmetic processing. A processor (such as a CPU) that constitutes the arithmetic processing element reads necessary data and software from a predetermined memory. This means that the object is “programmed” to execute arithmetic processing according to the software.

  One or a plurality of processors constituting each of the first server arithmetic processing element 110 and the second server arithmetic processing element 120 may be partly or entirely common or may be separate.

  The navigation device 200 has a self-position measurement function using GPS and a communication function with external devices including the navigation server 100, and is configured by a terminal device carried by a user or a terminal device mounted on a vehicle. Yes. The navigation device 200 includes an input device 201, an output device 202, a navigation storage element 204, a first navigation calculation processing element 210, and a second navigation calculation processing element 220.

  The input device 201 is configured by an operation button, a touch panel switch, or the like, and configured to allow input to the navigation device 200 at a target position intended by the user. As the input device 201, an imaging device and a recording device are mounted on the navigation device 200. The output device 202 includes a display device that can display and output the current position together with the navigation map. The output device 202 may display an image representing a switch as a touch panel.

  The navigation storage element 204 is configured to store data such as a navigation map including a road network constituted by a plurality of links.

  The first navigation calculation processing element 210 and the second navigation calculation processing element 220 are configured to execute calculation processing described later. One or a plurality of processors constituting each of the first navigation computation processing element 210 and the second navigation computation processing element 220 may be partly or entirely common or may be separate.

  The component of the present invention “recognizes” information means that the component receives information, retrieves information from a database, reads information from a storage device, and retrieves basic information. Execute predetermined arithmetic processing among all arithmetic processing for making the information available, such as calculating or estimating information by executing arithmetic processing, storing information in a storage device, etc. It is a concept that includes things.

(function)
“Probe information” is transmitted from each of the plurality of navigation devices 200 to the navigation server 100 (FIG. 2 / arrow S0). Each probe information represents a time-series measurement position ((latitude, longitude) or (latitude, longitude, altitude)) obtained by the positioning function of the navigation device 200.

  The first server arithmetic processing element 110 calculates the movement cost pattern τ (i, t) for each link L (i) based on the probe information according to a predetermined calculation rule (FIG. 2 / STEP 110). For example, a movement cost time change pattern is calculated from each of the plurality of probe information of each link L (i), and the calculation result is averaged to calculate the movement cost pattern τ (i, t).

  In addition to or in place of the probe information, movement is performed according to a predetermined calculation rule based on the traffic volume in the corresponding link detected by the traffic volume detector installed in some or all of the links L (i). A cost pattern τ (i, t) may be calculated.

As a result, for each link L (i), a movement cost pattern τ (i, t) up to the current time point t ₀ as represented by a curve on the t-τ plane in FIG. Stored in the server storage element 104.

  “First type environmental factor information” is transmitted from the first external device 200A to the navigation server 100 (FIG. 2 / arrow S1). “First-class environmental factor information” includes “first-class environment” such as weather, rainfall, or traffic regulation that can predict future aspects among environmental factors in each link L (i) or an area including the link L (i). "Factor". The first external device 200A includes a navigation device 200 in addition to a weather information station and a traffic information station server.

The first server arithmetic processing element 110 calculates the first type environmental factor pattern γ ₁ (i, t) in each link L (i) based on the first type environmental factor information according to a predetermined calculation rule (FIG. 2 / STEP 111). As a result, for each link L (i), for example, the first type environmental factor pattern γ ₁ (i, i) up to the current time t ₀ as represented by the curve on the t-γ ₁ plane in FIG. t) is determined and stored in the server storage element 104.

  The “second type environmental factor information” is transmitted from the second external device 200B to the navigation server 100 (FIG. 2 / arrow S2). “Type 2 environmental factor information” is the second of the environmental factors in each link L (i) or the area including the link, such as the presence or absence of sudden heavy rains or traffic accidents whose future aspects are unpredictable or difficult. It represents species environmental factors. The second external device 200B includes a navigation device 200 in addition to a weather information station and a traffic information station server.

The first server arithmetic processing element 110 calculates the second type environmental factor pattern γ ₂ (i, t) in each link L (i) based on the second type environmental factor information according to a predetermined calculation rule (FIG. 2 / STEP 112). As a result, for each link L (i), the second kind of environmental factor up to the current time point t ₀ as represented by, for example, curves on the t-γ _s plane and the t-γ _m plane in FIG. The patterns γ _s (i, t) and γ _m (i, t) are obtained and stored in the server storage element 104.

The recognition process of the movement cost pattern τ (i, t), the first type environmental factor pattern γ ₁ (i, t) and the second type environmental factor pattern γ ₂ (i, t) as described above is sequentially repeated. The recognition result is updated.

  In the navigation device 200, the user sets the destination point P2 through the input device 201 (FIG. 2 / STEP 210). The first navigation calculation processing element 210 recognizes the position of the navigation device 200 at this time as the departure point P1, and transmits information for specifying the departure point P1 and the destination point P2 to the navigation server 100 ( FIG. 2 / arrow S3).

In response to this, the first server computation processing element 110 searches for one or a plurality of server routes R connecting the departure point P1 and the destination point P2 based on the server map information (FIG. 2 / STEP 120). As a result, for example, as shown in FIG. 3, a server route R constituted by a plurality of links L (q _k ) (k = 1 to M) connecting the departure point P1 and the destination point P2 is searched. The first server arithmetic processing element 110 recognizes a plurality of links L (q _k ) constituting the server route R as designated links (FIG. 2 / STEP 121).

  Subsequently, the first server arithmetic processing element 110 searches for the “second period” (FIG. 2 / STEP 122). The search process will be described with reference to FIG.

The movement cost pattern τ (q _k , t) of each designated link L (q _k ) in the first period [t ₁ , t ₁ + T] with a width T starting from the first time t ₁ is _obtained from the server storage element 104. It is read (see FIG. 4A). The end time t ₁ + T of the first period coincides with the current time t ₀ . The end time t ₁ + T of the first period may be a time _earlier than the current time t ₀ .

The environmental factor of each designated link L (q _k ) in the first related period [t ₁ −Δt, t ₁ + T−Δt] that is before the first period by the designated period Δt and has the same width T as the first period. The pattern γ (q _k , t) = {γ ₁ (q _k , t), γ ₂ (q _k , t)} is read from the server storage element 104 (see FIG. 4A).

The designated period Δt may be different depending on the type of the environmental factor γ. For example, the designated period Δt (γ ₁ ) for the first type environmental factor γ ₁ may be set shorter than the designated period Δt (γ ₂ ) for the second type environmental factor γ ₂ . The designated period Δt may be zero for some or all environmental factors. That is, the first period and the first related period may coincide with some or all of the environmental factors.

The second degree of similarity of the environmental factor pattern γ (q _k , t) with respect to the first related period is equal to or more than the first reference value, is before the first related period, and has the same width T as the first related period. The related period [t ₂ −Δt, t ₂ + T−Δt] (t ₂ <t ₁ ) is searched (see FIG. 4B). From FIG. 4B, the environmental factor pattern γ (q _k , t) (see the broken line) in the first related period is similar to the environmental factor pattern γ (q _k , t) (see the solid line) in the second related period. You can see that The “first reference value” may be defined so as to increase continuously or stepwise as the period to be searched increases from the current time t ₀ to the past.

  The similarity between two variable value patterns is, for example, the interval between the start time and the end time after the start time and the end time of the two variable value patterns are aligned. It is calculated by integrating with time.

A period [t ₂ , t ₂ + T] after the specified period Δt from the second related period and having the same width T as the second related period is specified as the second period (see FIG. 4B).

With the requirement that the similarity of the movement cost pattern τ (q _k , t) to the first period [t ₁ , t ₁ + T] is equal to or greater than the second reference value, the period [t ₂ , t ₂ + T] is the first It may be specified as two periods. From FIG. 4B, the movement cost pattern τ (q _k , t) (see the broken line) in the first period is similar to the movement cost pattern τ (q _k , t) (see the solid line) in the second period. I understand that. The “second reference value” may be defined so as to increase continuously or stepwise as the period to be searched is further away from the current time point t ₀ .

Second server arithmetic processing element 120, moving cost pattern τ (q _k, t) until the present time t ₀ of the movement cost pattern τ (q _k, t) of the second period based on, each designated link L ( q _k) in estimating the movement cost of the current time t ₀ after τ (q _k) (Fig. 2 / STEP124). The estimation process will be described with reference to FIG.

For example, the movement cost pattern τ (q _k , t) after the end time t ₂ + T of the second period shown in FIG. 4 (b) is as shown by the broken line in FIG. 5 (a). It is estimated as a movement cost pattern τ (q _k , t) after time t ₀ .

The second server arithmetic processing element 120 has the environmental factor pattern γ (q _k , t) of the period (t ₁ + T <t) after the end of the first related period with respect to the period (t ₂ + T <t) after the end of the second related period. ) Is corrected for the movement cost pattern τ (q _k , t) in the period after the current time (t ₀ <t).

  The deviation between the two variable value patterns is calculated as, for example, a time change pattern of the deviation between the variable values at an arbitrary time after the start time and end time of the two variable value patterns are aligned.

Specifically, the environmental factor pattern γ (q _k , t> t ₂ + T−Δt) (see the broken line in FIG. 5B) for the period after the end of the second related period, and the period after the end of the first related period The environmental factor pattern γ (q _k , t> t ₁ + T−Δt) (see the solid line in FIG. 5B) is recognized. Since the environmental factor γ ₁ corresponds to the first type environmental factor Γ ₁ , the environmental factor γ ₁ in the period after the current time point t ₀ as shown by the solid line on the t-γ ₁ plane in FIG. Can be predicted.

Meanwhile, since environmental factors gamma _m corresponds to the second type environmental factor gamma _2, FIG. 5 (b) t-γ _m current time as indicated by the solid line in the plane t ₀ before and the first relevant period Only the environmental factor γ _m in the period [t ₁ + T−Δt, t ₀ (= t ₁ + T)] after the end can be acquired.

The environmental factor γ ₁ has a property that, for example, the movement cost τ (q _k ) increases as the value increases. For this reason, there is a period in which the deviation Δγ ₁ = γ ₁ (q _k , t> t ₁ + T−Δt) −γ ₁ (q _k , t> t ₂ + T−Δt) of the environmental factor γ ₁ is a positive value. In this case, the movement cost pattern τ (q _k , t) is corrected so that the movement cost τ (q _k ) in the period after the specified period Δt increases from the period (FIG. 5 (b) am (γ ₁ )reference). Meanwhile, if the deviation [Delta] [gamma] ₁ of the environmental factors gamma ₁ there is a time period is negative, as the movement cost in the period designated period Δt only later than the period τ (q _k) is decreased, moving cost pattern tau (Q _k , t) is corrected (same as above).

The environmental factors γ _s and γ _m have a property that, for example, the movement cost τ (q _k ) increases as the value increases. Therefore, if the deviation [Delta] [gamma] _m environmental factors gamma _m there is a time period which is positive, as the movement cost in the period designated period Δt only later than the period τ (q _k) is increased, moves the cost pattern tau (Q _k , t) is corrected (see FIG. 5 (b) am (γ _m )). Meanwhile, if the deviation [Delta] [gamma] _s of the environmental factors gamma _s there is a time period is negative, as the movement cost in the period designated period Δt only later than the period τ (q _k) is decreased, moving cost pattern tau (Q _k , t) is corrected (see FIG. 5 (b) am (γ _s )).

The second server arithmetic processing element 120 uses the corrected travel cost pattern τ (q _k , t) (see FIG. 5B) to navigate after the current time t ₀ in each designated link L (q _k ). The movement cost τ (q _k ) of the user of the device 200 or its moving means is estimated. The correction process is omitted, movement cost pattern tau before correction _{(q k, t> t 0} ) based on (see FIG. 5 (a) broken lines), moving cost tau (q _k in each designated link L (q _k) ) May be estimated.

The movement cost τ (q ₁ ) in the first designated link L (q ₁ ) after the current time t ₀ or a predetermined time Δt ₀ from the current time is estimated. From the current time point t ₀ , a predetermined time Δt ₀ , a sum Σ _{k = 1toj} τ (q _k ) of estimated movement costs from the _first designated link L (q ₁ ) to the jth designated link L (q _j ) The movement cost τ (q _{j + 1} ) in the j + 1-th designated link L (q _{j + 1} ) after elapses is estimated (see FIG. 3).

Then, the navigation server 100 transmits traffic information including the estimated travel required time τ (q _{j + 1} ) by the second server computation processing element 120 from the navigation server 100 to the navigation device 200 (FIG. 2 / arrow). S4).

  In response to this, the second navigation calculation processing element 220 searches for a navigation route r connecting the departure point P1 and the destination point P2 based on the traffic information and the navigation map information stored in the navigation storage element 204. (FIG. 2 / STEP 221). Thereby, a navigation route r that is the same as or similar to the server route shown in FIG. 3 is searched.

  The second navigation calculation processing element 220 outputs and displays the navigation route r, the current position of the navigation device 200, and the navigation map information around the current position on the output device 202. The estimated travel cost along the navigation route r is displayed with characters such as “the required travel time (travel cost) is minutes” and the color, pattern or shape of the link according to the length of the estimated travel cost It may be displayed so as to be visually distinguishable according to the difference.

When the search in the second period (FIG. 2 / STEP 122) fails, the estimation of the movement cost τ (q _k ) in each designated link L (q _k ) (FIG. 2 / STEP 124) is stopped. Accordingly, the traffic information (see FIG. 2 / arrow S4) is not transmitted from the navigation server 100 to the navigation device 200.

(Function and effect)
According to the navigation system that exhibits the above function, in view of the similarity of the environmental factor pattern γ (i, t) that affects the traffic state in each link L (i), the movement cost pattern τ ( i, t) is recognized as an estimation basis of the movement cost τ (i) after the current time t ₀ . Thereby, the further improvement of the estimation precision of the movement cost (tau) (i) as a traffic state variable value is achieved.

(Other embodiments of the present invention)
As another embodiment of the present invention, the second server arithmetic processing element 120 is configured so that each link is based on an environmental factor pattern γ (i, t) in a period (t> t ₁ + T−Δt) after the end of the first related period. The movement cost pattern τ (i, t) in the period (t> t ₁ + T) after the end of the first period in L (i) may be estimated.

DESCRIPTION OF SYMBOLS 100 ... Navi server, 104 ... Server storage element, 110 ... First server arithmetic processing element, 120 ... Second server arithmetic processing element, 200 ... Navigation device, 204 ... Navigation storage element, 210 ... First navigation arithmetic processing element, 220 ... 2nd navigation calculation processing element.

Claims (7)

After recognizing the traffic state variable value at each link constituting the road network and the time change pattern of the environmental factor affecting the traffic state, the similarity of the time change pattern of the environmental factor with respect to the first related period is the first. A first server arithmetic processing element that is configured to recognize a second related period of the same width that is equal to or greater than a reference value and before the first related period;
Of the time change pattern of the traffic state variable value recognized up to the current time point recognized by the first server computation processing element, the traffic state variable value in the second period of the same width after the second related period for a specified period. The traffic state variable value is estimated after the end of the first period of the same width after the specified period and after the current time point based on the time change pattern of the first link. And a two-server arithmetic processing element. The navigation server according to claim 1, wherein
The first server computation processing element has a similar degree of the time change pattern of the traffic state variable value with respect to the first period equal to or greater than a second reference value, and a period of the same width before the first period as the first period. A navigation server configured to be recognized as two periods. In the navigation server according to claim 1 or 2,
The second server computation processing element, based on the time change pattern of the environmental factor in the period after the end of the first related period, the time change of the traffic state variable value in the period after the end of the first period in each link A navigation server configured to estimate a pattern. In the navigation server according to claim 3,
The second server computation processing element is based on a deviation of a time change pattern of the environmental factor in a period after the end of the first related period with respect to a period after the end of the second related period, and after the end of the first period and the current time point Subsequent correction of the time change pattern of the traffic state variable value, and based on the corrected time change pattern of the traffic state variable value, the traffic state variable after the end of the first period and after the current time point in each link. A navigation server configured to estimate a value. In the navigation server according to claim 3 or 4,
The first server arithmetic processing element recognizes a predictable first type environmental factor among the environmental factors in a future period after the current time point based on communication with the first external device, and with the second external device. Based on communication, configured to recognize an unpredictable second type environmental factor or the first and second type environmental factors among the environmental factors in the past period after the end of the second related period and before the current time point Navi server characterized by being. In the navigation server according to any one of claims 1 to 5,
The first server arithmetic processing element recognizes a target designated link from the road network based on communication with a navigation device, and then the time change of the traffic state variable value up to the current point in the designated link Configured to recognize patterns,
The second server computation processing element estimates the traffic state variable value after the end of the first period of the same width after the specified period from the first related period in the specified link and after the current time point; A navigation server configured to cause the navigation device to recognize the estimation result or designated traffic information based on the estimation result based on the communication.   It is comprised by the navigation server as described in any one of Claims 1-6, and a navigation apparatus, The said 1st server arithmetic processing element is based on communication with the said navigation apparatus, and until the present time in each said link The navigation system is configured to recognize the traffic state variable values of the vehicle, or the time change patterns of the traffic state variable values and the environmental factors.

Images