JP2012221167A - Traveling information arithmetic device and traveling information arithmetic method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To estimate the cycle of a traffic light even when the accuracy of a GPS is low.SOLUTION: A traveling information arithmetic device 100 includes: a traveling information acquisition part 102 for acquiring traveling information including the measured location of an automobile and a measurement time via a network 20 from an in-vehicle unit loaded on the automobile; a stop detection part 104 for specifying a period when the automobile stays within a predetermined location range on the basis of the traveling information acquired by the traveling information acquisition part 102; a signal pre-stop period acquisition part 106 for determining whether or not a location range corresponding to the period specified by the stop detection part 104 and the already known location of the traffic light are made to correspond to each other, and for, when the result of determination is positive, acquiring the period specified by the stop detection part 104 as a period corresponding to the traffic light; and a cycle arithmetic part 142 for calculating a period when a predetermined traffic light is turned into a red light by combining a plurality of periods to be obtained by the signal pre-stop period acquisition part 106 about the traffic light.

Description

  The present invention relates to a travel information calculation device and travel information calculation information, and more particularly to a travel information calculation technique for collecting and processing travel information from a vehicle.

  If a car traveling on a road can travel continuously without being stopped by a traffic signal (hereinafter simply referred to as a traffic light), the fuel efficiency of the car will be significantly improved. This is because a relatively large amount of fuel is required to stop and start the automobile.

  Therefore, first of all, it is conceivable to acquire and use the cycle of the traffic light directly from the traffic light (for example, see Patent Document 1). However, this method is not realistic. This is because, at present, no mechanism has been established for transmitting the cycle of the traffic light from each traffic light to the vehicle. Although there is currently a movement to develop such a mechanism for research purposes, etc., it is unlikely that such a mechanism will be attached to all the traffic signals throughout the country, and even if it is realized, it will take a considerable amount of time. Will.

  Another possible solution is to gather information from the moving car and estimate the traffic light cycle. For example, in Patent Document 2, the flow in which each vehicle in a train that stops in front of a traffic light starts with a green light or stops with a red traffic light is considered as a flow of dense waves of traffic flow. A method for estimating the switching time is disclosed.

JP 2008-296798 A JP 2009-116508 A

  In the method disclosed in Patent Document 2, it is necessary to measure the moving distance of the vehicle in the vicinity of the intersection with relatively high accuracy, and therefore, it is necessary to position the vehicle relatively accurately. Although the accuracy of positioning systems such as GPS (Global Positioning System) for identifying the position of a vehicle has been improving year by year, there are still those that can provide high accuracy as required by the technique disclosed in Patent Document 2. Few. Therefore, in the method disclosed in Patent Document 2, it is not possible to collect quality and quantity data necessary for estimation, or there is a possibility that it takes time to collect the data.

  The present invention has been made in view of these problems, and an object of the present invention is to provide a technique that can estimate the cycle of a traffic light from information obtained from a vehicle even if the accuracy of the positioning system is not so high.

  One embodiment of the present invention relates to a travel information calculation device. The travel information calculation device is acquired by a travel information acquisition unit that acquires travel information including a measured position and measurement time of a vehicle from a communication device mounted on the vehicle via a network, and a travel information acquisition unit. Based on the travel information, the stop detection unit that identifies the period during which the vehicle remains within the predetermined position range, the position range corresponding to the period specified by the stop detection unit, and the position of a known traffic signal A stop period acquisition unit that acquires a period specified by the stop detection unit as a period corresponding to the traffic signal when it is determined that it corresponds.

  According to this aspect, even if the accuracy of the measured position of the vehicle is relatively low, if the position stays within the predetermined position range, it can be detected as a stop of the vehicle.

  It should be noted that any combination of the above-described constituent elements, or those obtained by replacing the constituent elements and expressions of the present invention with each other between apparatuses, methods, systems, computer programs, recording media storing computer programs, and the like are also included in the present invention. It is effective as an embodiment of

  According to the present invention, the cycle of a traffic light can be estimated from information obtained from a vehicle even if the accuracy of the positioning system is not so high.

It is a schematic diagram which shows the structure of a navigation system provided with the driving | running | working information calculating apparatus which concerns on embodiment. It is explanatory drawing for demonstrating driving | running | working information. It is explanatory drawing for demonstrating the estimation of the cycle of the traffic light performed in the travel information calculating apparatus which concerns on this Embodiment. It is a block diagram which shows the function and structure of the driving | running | working information calculating apparatus which concern on embodiment. It is a data structure figure which shows an example of the driving | running | working information holding part of FIG. FIG. 5 is a data structure diagram illustrating an example of a rearrangement information holding unit in FIG. 4. It is a flowchart which shows an example of a series of processes in the rearrangement information processing part of FIG. FIG. 5 is a data structure diagram illustrating an example of a stop period holding unit in FIG. 4. FIG. 5 is a data structure diagram illustrating an example of a pre-signal stop period holding unit in FIG. 4. It is explanatory drawing for demonstrating the measurement red signal period hold | maintained at the measurement cycle holding | maintenance part of FIG. It is a data structure figure which shows an example of the prediction cycle holding | maintenance part of FIG. It is explanatory drawing for demonstrating the calculation of NS speed. It is a data structure figure which shows an example of the NS speed holding | maintenance part of FIG. It is explanatory drawing for demonstrating the production | generation process of NS route in the route production | generation part of FIG. It is a flowchart which shows an example of a series of processes in the driving | running | working information calculating apparatus of FIG.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, members, and processes shown in the drawings are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate.

  FIG. 1 is a schematic diagram illustrating a configuration of a navigation system 2 including a travel information calculation device 100 according to an embodiment. The navigation system 2 includes vehicle-mounted devices 12 and 16 mounted on a vehicle such as the automobiles 10 and 14, a base station 18, a network 20 such as the Internet, and a travel information calculation device 100 according to the present embodiment. .

  The vehicle-mounted devices 12 and 16 are measured positions (hereinafter referred to as measurement positions) of the automobiles 10 and 14 on which they are mounted using a positioning system such as GPS, and the times when the measurements are performed. Get the measurement time. This measurement position may be represented by an arbitrary coordinate system, for example, represented by latitude and longitude. The vehicle-mounted devices 12 and 16 generate travel information including the vehicle ID, the measurement position, and the measurement time for identifying the automobiles 10 and 14 in which the on-vehicle devices 12 and 16 are mounted, and the generated travel information is transmitted to the base station 18 and the network 20. To the travel information computing device 100. From this viewpoint, it can be said that the vehicle-mounted devices 12 and 16 are communication devices that transmit travel information. Moreover, acquisition of a measurement position and measurement time, and transmission of traveling information are performed at predetermined time intervals, for example, at intervals of 4 seconds. The travel information computing device 100 receives and holds the travel information transmitted in this way.

  The vehicle-mounted devices 12 and 16 also transmit a route request for requesting route guidance including the position of the departure place and the position of the destination to the travel information computing device 100 via the base station 18 and the network 20. The vehicle-mounted devices 12 and 16 receive route information generated by the travel information computing device 100 in response to the route request via the network 20 and the base station 18. The vehicle-mounted devices 12 and 16 display a navigation screen based on the received route information on a display (not shown).

  The base station 18 is provided in a building or the like near the road, and communicates with the vehicle-mounted devices 12 and 16 by radio. The base station 18 transmits information received from the vehicle-mounted devices 12 and 16 to the network 20, and transmits information transmitted from the network 20 to the vehicle-mounted devices 12 and 16 to the vehicle-mounted devices 12 and 16. The network 20 is connected to the base station 18 and the travel information calculation device 100.

  FIG. 2 is an explanatory diagram for explaining travel information. The up and down direction in FIG. 2 is, for example, the north-south direction, and seven two-lane roads 22a, 22b, 22c, 22d, 22e, 22f, and 22g are provided along this direction. The left-right direction in FIG. 2 is, for example, the east-west direction, and four two-lane roads 24a, 24b, 24c, 24d are provided along this direction. At each of the intersections between the two-lane road in the north-south direction and the two-lane road in the east-west direction, two traffic lights are provided in total, two for the two-lane road in the north-south direction and two for the two-lane road in the east-west direction.

  Here, it is assumed that the automobile 10 passes through the links L1, L2, L3, L4, L5, L6, L7, L8, and L9 in this order, and the vehicle-mounted device 12 of the automobile 10 transmits the traveling information during that time. A gray circle in FIG. 2 represents a measurement position included in the travel information transmitted from the vehicle-mounted device 12.

  In general, the accuracy of positioning by GPS is coarse compared to the width of the road, and therefore the automobile 10 actually runs on the road, but the measurement position is often slightly off the road. In particular, when there are buildings around, the measurement position may deviate greatly from the road (for example, circle 26 in FIG. 2). The travel information calculation apparatus 100 may process the received travel information using a known map matching technique that estimates an accurate position from information on a known road map and a trajectory before and after a car. As a result of the map matching, for example, the measurement position indicated by the circle 26 is corrected to the position indicated by the circle 28.

  Assume that the automobile 10 stops at a red light at an intersection K1 where the inter-intersection link L1 and the inter-intersection link L2 intersect, and an intersection K2 where the inter-intersection link L7 and the inter-intersection link L8 intersect. Then, as shown in FIG. 2, the measurement positions around the intersection K1 and the intersection K2 are detected together within the position ranges 30 and 32 having a predetermined size. Note that due to the coarse accuracy of GPS, even if the automobile 10 is actually stopped, the measurement positions are dispersed around the actual stop position.

  In this embodiment, the size of the position range is set based on the assumed GPS accuracy. The driving information calculation device 100 determines that the automobile is stopped within the position range when a predetermined number or more of measurement positions are subsequently detected within the position range of the size. The reason why the automobile stops is that it stops at a parking lot in addition to stopping at a red signal. Therefore, the travel information computing device 100 determines the position range in which the automobile is stopped and a known traffic light. It is determined whether or not they correspond based on the relationship with the positions of. When it determines with corresponding | compatible, the driving | running | working information calculating apparatus 100 acquires the period when a measurement position is detected within the position range. The travel information computing device 100 determines that the automobile is stopped at the red signal of the traffic light during the period acquired as described above. As a result, the period during which the traffic light is red can be estimated sufficiently accurately even when the coarse accuracy of GPS is taken into account.

  FIG. 3 is an explanatory diagram for explaining the estimation of a traffic light cycle performed in the travel information computing device 100 according to the present embodiment. The horizontal axis of the graph shown in FIG. 3 indicates time, and the vertical axis indicates distance. This distance is a distance along the two-lane road 24c in the east-west direction in FIG. In FIG. 3, the inter-intersection links L4, L5, L6, and L7 shown in FIG. 2 are particularly shown. The gray circle in FIG. 3 corresponds to a set of measurement position and measurement time included in the travel information transmitted from the vehicle-mounted device. When attention is paid to the intersection K3 at which the inter-intersection link L4 and the inter-intersection link L5 intersect, it is considered that the automobile indicated by the arrows A1, A2, A6, A7, and A11 has passed the intersection K3 with a green light. In addition, for the automobiles indicated by arrows A3, A4, A5, A8, A9, and A10, the measurement position is continuously detected around the position of the traffic light provided at the intersection K3. It is thought to have stopped.

  By mapping the trajectories of many automobiles in this way, the traffic light cycle can be estimated. For example, in the example of FIG. 3, the period from the time “xx: y1y2: z1z2” to the time “xx: y3y4: z3z4” at which the measurement positions are dense for the intersection K3 and the time “xx: y5y6: z5z6” to the time “ It can be estimated that during the period up to “xx: y7y8: z7z8”, the traffic lights installed in the east-west direction were red. From this estimation result, assuming that the traffic light repeats the red signal and the blue signal in the same cycle the next day, the period from the time `` xx: y1y2: z1z2 '' to the time `` xx: y3y4: z3z4 '' The signal from the time “xx: y5y6: z5z6” to the time “xx: y7y8: z7z8” is also assumed to be red.

  As described above, the travel information calculation apparatus 100 collects and maps the travel information, and estimates the period during which the traffic light is red. Then, the travel information calculation device 100 estimates a period in which the traffic light will be red in the future based on the information of the estimated period. Thus, even in a situation where it is difficult to directly obtain the traffic light cycle, the traffic light cycle can be statistically estimated.

  The method of controlling the cycle of the traffic light may vary depending on, for example, the road type of the road where the traffic signal is provided, the day of the week, the weekday / Saturday, Sunday and public holidays, or the day and night. However, in the following, for the sake of easy understanding, it is assumed that the traffic signal to be estimated repeats a red signal and a blue signal in the same cycle every day. In addition, since the period when the traffic light is a yellow signal is generally much shorter than the period when the traffic light is a blue signal or a red signal, it will not be considered below. However, if the method of controlling the traffic light cycle varies depending on the road type, day of the week, etc., for example, the traffic light cycle control method is considered to be the same, or the traffic light cycle control method is considered to be the same. It will be apparent to those skilled in the art who have touched this specification that the same processing as described below may be performed in units of periods. Further, it will be apparent to those skilled in the art who have touched the present specification that the same explanation as described below is established even when the yellow signal, the blinking red signal, and the like of the traffic light are taken into consideration.

  FIG. 4 is a block diagram illustrating functions and configurations of the travel information computing device 100 according to the embodiment. Each block shown here can be realized by hardware such as a computer (CPU) (central processing unit) and other elements and mechanical devices, and software can be realized by a computer program or the like. Here, The functional block realized by those cooperation is drawn. Therefore, it is understood by those skilled in the art who have touched this specification that these functional blocks can be realized in various forms by a combination of hardware and software.

  The travel information calculation device 100 includes a travel information acquisition unit 102, a stop detection unit 104, a pre-signal stop period acquisition unit 106, a calculation unit 108, a route information provision unit 110, a cycle update unit 112, and map information storage. Unit 114, travel information holding unit 116, rearrangement information holding unit 118, stop period holding unit 120, pre-signal stop period holding unit 122, prediction cycle holding unit 124, measured cycle holding unit 125, NS A speed holding unit 126.

  The map information holding unit 114 holds given road map information, and holds, for example, a traffic signal ID that specifies the position and length of the link between intersections and a traffic signal, and the position of the traffic signal. The map information holding unit 114 may hold information obtained from, for example, a digital road map database provided by the Japan Digital Road Map Association.

  The travel information acquisition unit 102 acquires travel information from the vehicle-mounted device mounted on the automobile via the network 20 and registers the travel information in the travel information holding unit 116. The travel information acquisition unit 102 includes a travel information reception unit 128, a map matching unit 130, and a travel information registration unit 132.

The travel information receiving unit 128 receives travel information from the network 20.
The map matching unit 130 extracts the measurement position from the travel information received by the travel information receiving unit 128. The map matching unit 130 performs map matching processing on the extracted measurement position with reference to the map information holding unit 114.
The travel information registration unit 132 registers travel information including the measurement position subjected to the map matching process by the map matching unit 130 in the travel information holding unit 116.

  FIG. 5 is a data structure diagram illustrating an example of the travel information holding unit 116. The travel information holding unit 116 holds the vehicle ID included in the travel information, the measurement time, and the latitude and longitude as the measurement position in association with each other.

  Returning to FIG. 4, the stop detection unit 104 determines whether or not the automobile stays within the position range of the predetermined size based on the travel information held in the travel information holding unit 116. Is determined, a reference position representing the position range is specified, and a period remaining in the position range is specified as a stop period. The stop detection unit 104 includes an information rearrangement unit 134 and a rearrangement information processing unit 136.

The information rearrangement unit 134 extracts the travel information from the travel information holding unit 116 for each vehicle ID, sorts the extracted travel information with respect to the measurement time, and registers the information in the rearrangement information holding unit 118.
FIG. 6 is a data structure diagram illustrating an example of the rearrangement information holding unit 118.

  FIG. 7 is a flowchart illustrating an example of a series of processes in the rearrangement information processing unit 136. The rearrangement information processing unit 136 selects a vehicle ID to be processed from vehicle IDs that are not yet processed (S202). The rearrangement information processing unit 136 extracts travel information about the processing target vehicle ID from the rearrangement information holding unit 118 (S204). The rearrangement information processing unit 136 calculates the distance between the measurement positions in the ascending order of the measurement time for the extracted travel information (S206). For example, the rearrangement information processing unit 136 calculates a distance between a measurement position at a certain measurement time (hereinafter referred to as a first measurement time) and a measurement position at the next measurement time (hereinafter referred to as a second measurement time).

  The rearrangement information processing unit 136 compares the calculated distance with a predetermined error equivalent distance (S208). When the calculated distance is smaller (Y in S208), the rearrangement information processing unit 136 temporarily holds the first measurement time, the measurement position at that time, the second measurement time, and the measurement position at that time. (S210). The rearrangement information processing unit 136 increments the number of detections, which is a parameter for detecting the stop of the automobile (S212). For example, the rearrangement information processing unit 136 initially sets the detection number from 0 to 2, and thereafter increases the detection number by one. The rearrangement information processing unit 136 determines whether there is travel information that has not yet been subject to distance calculation in the extracted travel information (S214). If it exists (Y in S214), the process returns to S206.

  When the calculated distance is larger or equal to the error equivalent distance (N in S208) as a result of the comparison in step S208, the rearrangement information processing unit 136 determines the number of detections at that time and the predetermined threshold detection number. Are compared (S216). When the number of detections is larger than the threshold detection number (Y in S216), the rearrangement information processing unit 136 calculates the average position of the measurement positions held in the temporary holding unit, and uses the calculation result as the stop reference position. Specify (S218). Further, the rearrangement information processing unit 136 specifies the first time among the measurement times registered in the temporary holding unit as the start time of the stop period and the last time as the end time of the stop period (S218).

  The rearrangement information processing unit 136 associates the vehicle ID, the specified stop reference position, the specified stop period start time, and the specified stop period end time with the stop period holding unit 120. (S220). Thereafter, the rearrangement information processing unit 136 returns the number of detections to 0, and the process proceeds to step S214. When the number of detections is smaller than or equal to the threshold detection number as a result of the comparison in step S216 (N in S216), the rearrangement information processing unit 136 returns the detection number to 0 and advances the process to step S214.

  When it is determined in step S214 that there is no unprocessed travel information (N in S214), the rearrangement information processing unit 136 still has rearrangement information among the vehicle IDs registered in the rearrangement information holding unit 118. It is determined whether there is a vehicle ID that has not been processed by the processing unit 136 (S222). When there is an unprocessed vehicle ID (Y in S222), rearrangement information processing unit 136 advances the process to step S202. The rearrangement information processing unit 136 ends the process when there is no unprocessed vehicle ID (N in S222).

  In this way, the rearrangement information processing unit 136 determines that the reference position of the position range if the automobile stays within the position range having a size based on the error-corresponding distance longer than the threshold detection number × the travel information acquisition interval. And the stop period remaining there are registered in the stop period holding unit 120.

The error equivalent distance may be set to a value corresponding to the magnitude of the error assumed for the measurement position, and may be determined based on, for example, a GPS error.
Further, an upper limit value of the number of detections may be provided based on a general length of a period during which the traffic light is red. In this case, for example, it is possible to detect a case where the automobile cannot pass through the traffic signal in one cycle of the traffic signal, and discard the data in such a case.
Further, when the vehicle turns right or left after staying within the position range, the data may be discarded. This is because, in the case of a right turn or a left turn, the stop period can vary depending on whether there is a car from the opposite lane or a pedestrian crossing a pedestrian crossing in addition to a traffic light.

  FIG. 8 is a data structure diagram illustrating an example of the suspension period holding unit 120. The stop period holding unit 120 holds the vehicle ID, the reference position of the stop, the start time of the stop period, and the end time of the stop period in association with each other.

  Returning to FIG. 4, the pre-signal stop period acquisition unit 106 determines whether or not the reference position of the stop specified by the stop detection unit 104 corresponds to the position of the known traffic signal. A stop period corresponding to the reference position is acquired as a pre-signal stop period corresponding to the traffic light. The stop period before the signal is, for example, a period in which the automobile is stopped in front of the traffic signal due to a red signal of the traffic signal. However, for example, there may be a case where the vehicle stops temporarily near the traffic light for getting on and off, so the stop period before the signal can be said to be a candidate for a period in which the vehicle stops at a red signal. The pre-signal stop period acquisition unit 106 includes a position correspondence determination unit 138 and a pre-signal stop period specifying unit 140.

  The position correspondence determination unit 138 obtains a stop reference position from the stop period holding unit 120. The position correspondence determining unit 138 acquires the position of the traffic light closest to the acquired reference position from the map information holding unit 114. The position correspondence determining unit 138 calculates the distance between the acquired reference position and the acquired traffic signal position. When the calculated distance is smaller than the predetermined correspondence distance, the position correspondence determination unit 138 determines that the acquired reference position corresponds to the nearest traffic signal. This corresponding distance may be set to be the same as the error equivalent distance, for example.

When the position correspondence determination unit 138 determines that the reference position corresponds to the traffic signal, the stop period specifying unit 140 before the signal transmits a stop period corresponding to the reference position from the stop period holding unit 120 to the signal corresponding to the traffic signal. Acquired as the previous suspension period. The pre-signal stop period specifying unit 140 associates the traffic signal ID for specifying the traffic signal, the start time of the pre-signal stop period acquired for the traffic signal, and the end time of the pre-signal stop period acquired for the traffic signal. To the pre-signal stop period holding unit 122.
FIG. 9 is a data structure diagram illustrating an example of the pre-signal stop period holding unit 122.

Returning to FIG. 4, the calculation unit 108 includes a cycle calculation unit 142 and an NS speed calculation unit 144.
The cycle calculation unit 142 calculates a period during which the traffic signal is red by combining a plurality of stop periods before the signal acquired by the stop period before signal acquisition unit 106 for a predetermined traffic signal.

  For example, the cycle calculation unit 142 extracts the pre-signal stop period for a predetermined traffic light from the pre-signal stop period holding unit 122. When N (N is an integer equal to or greater than 2) of the pre-signal stop periods of the extracted pre-signal stop periods overlap, the cycle calculation unit 142 determines that the predetermined signal becomes a red signal during the overlap period. The actual measured red signal period is determined. The value of N may be determined in consideration of measurement position errors and the like.

  For example, if N = 3 for the pre-signal stop period holding unit 122 shown in FIG. 9, three pre-signal stop periods “2009/5/2 14:20:19 to 2009/5/2 14 for the traffic signal ID“ TL12 ”14. : 20:39 "," 2009/5/2 14: 20: 21-2009 / 5/2 14:20:40 "," 2009/5/2 14: 20: 23-2009 / 5/2 14:20 : 41 ”is overlapped, the cycle calculation unit 142 uses the traffic signal ID“ TL12 ”for the period“ 2009/5/2 14:20:23 to 2009/5/2 14:20:39 ”where they overlap. It is determined as the measured red signal period of the specified traffic light.

  The cycle calculation unit 142 registers the determined measured red light period and the traffic signal ID of a predetermined signal in the measured cycle holding unit 125 in association with each other. Thereby, it is possible to measure and accumulate the period, that is, the cycle in which each traffic light is red from the collected traveling information.

  FIG. 10 is an explanatory diagram for explaining the measured red signal period held in the measured cycle holding unit 125. The horizontal axis of the graph shown in FIG. 10 indicates time, and the vertical axis indicates distance. This distance is a distance along the two-lane road 24c in the east-west direction in FIG. FIG. 10 particularly shows the inter-intersection links L3, L4, L5, L6, and L7 shown in FIG. The current time indicated by the alternate long and short dash line in FIG. 10 indicates the current time at which the travel information held in the travel information holding unit 116 is processed. Hereinafter, the direction from east to west is assumed to be up. The actual measurement cycle holding unit 125 is an actual red signal period 32 in which the red signal is generated for the traffic signal 30 in the east-west direction among the four traffic signals provided at the intersection K4 where the inter-intersection link L3 and the inter-intersection link L4 intersect. , 34 are held. The actual measurement cycle holding unit 125 similarly holds the actual red signal period for the other traffic lights.

  The cycle calculation unit 142 predicts a period during which a predetermined traffic signal will become a red signal in the future from the information held in the measured cycle holding unit 125. In particular, in the present embodiment, as described above, the prediction target traffic light is predicted on the assumption that the same cycle is repeated every day. That is, if a traffic light has been red from 14:10:15 to 36 seconds in the past, it is predicted that the traffic light will also be red from 14:10:15 to 36 seconds today and the next day. The cycle calculation unit 142 obtains the measured red signal period for several days or months for each traffic light from the measured cycle holding unit 125, and statistically processes them for each day.

The cycle calculation unit 142 calculates a time zone in one day in which measured red signal periods equal to or more than M (M is an integer of 2 or more) days overlap, and a predicted red signal that is a time zone in which the traffic light will be a red signal. It may be determined as a time zone. For example, for a certain traffic light, the actual red light period is 14:30:25 to 14:30:45 for 1 day before, 14:30:24 to 14:30:46 for 2 days, and 14:30 for 3 days before. When the time is from 25 minutes to 14:30 minutes and 44 seconds, the cycle calculation unit 142 uses the time zone of 14:30:25 to 14:30:44, which is the overlapping time zone, as the predicted red signal time zone. decide.
The cycle calculation unit 142 registers the determined predicted red light time zone in the predicted cycle holding unit 124 for each traffic light.

  FIG. 11 is a data structure diagram illustrating an example of the prediction cycle holding unit 124. The prediction cycle holding unit 124 holds the traffic signal ID and the predicted red light time period in association with each other.

  Returning to FIG. 4, the NS speed calculation unit 144 is a speed at which an automobile that has passed a certain traffic light can pass the next traffic light without being stopped by a red signal based on the information held in the prediction cycle holding part 124. Non-stop speed (hereinafter referred to as NS speed) is calculated. In particular, the NS speed calculation unit 144 calculates, as an NS speed, the speed at which a car that has entered a link between intersections at a certain time advances the inter-intersection link of the same road type as that of the link between the intersections most frequently. The NS speed calculation unit 144 correlates the calculated NS speed, the cross-intersection link ID that identifies the corresponding inter-intersection link, the up-and-down link, and the entry time that is the time to enter the inter-intersection link. At the same time, it is registered in the NS speed holding unit 126.

  FIG. 12 is an explanatory diagram for explaining the calculation of the NS speed. The horizontal axis of the graph shown in FIG. 12 indicates time, and the vertical axis indicates distance. This distance is a distance along the two-lane road 24c in the east-west direction in FIG. FIG. 12 shows the inter-intersection links L3, L4, L5, L6, L7, and L8 shown in FIG. In FIG. 12, predicted red signal time zones 36 and 38 held in the predicted cycle holding unit 124 for the traffic light 30 are shown. The predicted red signal time period held in the predicted cycle holding unit 124 is also shown for other traffic lights.

Here, the NS speed calculation unit 144 calculates the speed indicated by the slope of the arrow A12 as the NS speed for a car that enters the cross-intersection link L4 at time T1 of the day. For example, even when the vehicle travels on the inter-intersection link L4 at the speed indicated by the inclination of the arrow A13, the intersection K3 can pass non-stop. However, in that case, it is predicted to stop at a red light at the intersection K2 where the inter-intersection link L7 and the inter-intersection link L8 intersect. On the other hand, when the vehicle travels at the speed indicated by the inclination of the arrow A12, it is expected that the intersection K2 can also pass non-stop.
Similarly, the NS speed calculation unit 144 calculates the speed indicated by the slope of the arrow A16 instead of the arrow A15 as the NS speed for a car that enters the crossing link L4 up at time T2 in the day.

  FIG. 13 is a data structure diagram illustrating an example of the NS speed holding unit 126. The NS speed holding unit 126 holds an inter-intersection link ID, an up / down distinction, an entry time for an inter-intersection link, and an NS speed in association with each other.

  Returning to FIG. 4, the NS speed calculation unit 144 acquires from the map information holding unit 114 the legal speed limit set for the link between intersections corresponding to the calculated NS speed. When the calculated NS speed exceeds the acquired speed limit, the NS speed calculation unit 144 discards the NS speed. Alternatively, the NS speed calculation unit 144 registers the NS speed in the NS speed holding unit 126 together with a warning. In other words, the NS speed calculation unit 144 performs processing for leaving such NS speed as a value but not for the user.

  The route information providing unit 110 provides route information for the car navigation function of the vehicle-mounted device mounted on the automobile via the network 20. The route information providing unit 110 includes a route generation unit 146 and a route information transmission unit 148.

The route generation unit 146 receives a route request from the vehicle-mounted device via the network 20. When the route request is received, the route generation unit 146 generates an NS route based on the road map information held in the map information holding unit 114 and the NS speed held in the NS speed holding unit 126. The route generation unit 146 generates route information including an NS route and a set of NS speeds related to the NS route, a fastest route based on a known travel speed, and a set of the travel speed.
The route information transmission unit 148 transmits the route information generated by the route generation unit 146 to the in-vehicle device that is the transmission source of the route request via the network 20.

  FIG. 14 is an explanatory diagram for explaining NS route generation processing in the route generation unit 146. It is assumed that there are a plurality of roads that can be driven between the starting position 50 and the destination position 52 included in the received route request as shown in FIG. In FIG. 14, for each link between intersections, the current travel speed (the speed at which the vehicle is actually traveling on the route, which can be acquired from the probe vehicle in real time) and the NS speed holding unit 126 are acquired. NS speed is shown.

  The route generation unit 146 acquires the NS speed at each inter-intersection link from the NS speed holding unit 126 with reference to the entry time when the vehicle that has transmitted the route request enters the inter-intersection link when traveling on the route. To do. For example, when it is calculated that a certain cross-intersection link passes in 6 seconds (the distance of the cross-intersection link is known from the road map information held in the map information holding unit 114, the required time is calculated from the NS speed) If the entry time to the start intersection link is 15:00, the entry time to the next intersection link is 15:00:06.

  The fastest route is a combination of routes having the fastest travel speed, and is, for example, a route indicated by a one-dot chain line in FIG. However, in order to simplify the explanation here, the time for turning the intersection is assumed to be zero. The route generation unit 146 generates such a fastest route.

  The NS route is a combination of routes having the earliest NS speed among NS speeds lower than the current travel speed, and is, for example, a route indicated by a broken line in FIG. In FIG. 14, the second NS speed from the bottom is 35, but the third NS speed from the bottom is 40, which is larger than 35. Therefore, the third path from the bottom is part of the NS route. Selected. The route generation unit 146 generates such an NS route.

  For the NS route, it will take more time than the fastest route if the travel time of each road link is accumulated, but it is likely that the intersection can be driven non-stop, so it may reach the destination earlier than the fastest route. .

  Returning to FIG. 4, the route information providing unit 110 may provide the NS speed to the vehicle-mounted device when the car navigation function of the vehicle-mounted device mounted on the automobile is performing route guidance. That is, the route information providing unit 110 determines how far along the route the vehicle is currently traveling based on the route selected by the driver of the vehicle. The route information providing unit 110 extracts, from the NS speed holding unit 126, the NS speed at the cross-intersection link currently traveling from the determination result. When extracting the NS speed, the route information providing unit 110 extracts one having the same entry time to the inter-intersection link. The route information providing unit 110 sends the extracted NS speed to the vehicle that is traveling on the route, and displays the information on the navigation screen or by voice.

  Alternatively, the route information providing unit 110 may transmit the NS speed to a portable car navigation system, a smartphone, a mobile phone, or the like, and display the NS speed on the screen or convey it by voice. The route information providing unit 110 may provide the NS speed in the link between intersections of the route when the vehicle makes a right or left turn.

  In addition, the route information providing unit 110 displays the NS speed corresponding to the vehicle position when the car navigation function of the vehicle-mounted device mounted on the car does not provide route guidance but displays the vehicle position. May be provided.

  Regarding the cycle update unit 112, in the traffic lights at a later date, in the case where a car that is supposed to be a red light and a car that is stopped despite being a green light come to be seen from the driving information, including before and after the traffic light, etc. It is desirable to check the running information and re-estimate the cycle. This may be due to the fact that a new traffic signal was installed, the cycle of an existing traffic signal was changed, or the cycle was corrected by the police.

  The cycle update unit 112 includes a period determination unit 150 and a period update unit 152. The period determination unit 150 determines the consistency between the pre-signal stop period acquired by the pre-signal stop period acquisition unit 106 and the corresponding past actual red signal period held by the actual cycle holding unit 125. That is, the period determination unit 150 determines that the acquired stop period before signal overlaps with the predicted red signal time period held in the prediction cycle holding unit 124 by a predetermined ratio or more, and otherwise matches. Judge that not.

  If the period determination unit 150 determines that the period does not match, the period update unit 152 includes the pre-signal stop period acquired by the pre-signal stop period acquisition unit 106 and the actual cycle holding unit according to the pre-signal stop period acquired thereafter. 125 is updated. For example, when the period determination unit 150 determines that there is no matching, the period update unit 152 may discard the information stored in the actual measurement cycle holding unit 125 for the traffic signal determined to be inconsistent. The cycle calculation unit 142 may calculate the actual measured red signal period of the traffic light by combining the pre-signal stop period acquired thereafter for the traffic signal, and may register it in the actual cycle holding unit 125.

  In the above-described embodiment, examples of the holding unit are a hard disk and a memory. Based on the description in this specification, each unit is realized by a CPU (not shown), an installed application program module, a system program module, a memory that temporarily stores the contents of data read from the hard disk, and the like. It is understood by those skilled in the art who have touched this specification that they can do this.

The operation of the travel information computing device 100 having the above configuration will be described.
FIG. 15 is a flowchart illustrating an example of a series of processes in the travel information computing device 100. The travel information computing device 100 acquires travel information (S302). The travel information computing device 100 specifies the reference position and the stop period by the process shown in FIG. 7 (S304). The travel information computing device 100 acquires the pre-signal stop period (S306). The travel information computing device 100 computes the measured red signal period (S308). The travel information computing device 100 computes a predicted red light time zone (S310). The travel information calculation device 100 calculates the NS speed (S312).

  According to the travel information computing device 100 according to the present embodiment, the situation where the mechanism for receiving the cycle information directly from the traffic light is not provided on the traffic light side or the vehicle side and the GPS that can be used by general vehicles is provided. In a situation where the accuracy is relatively low, it is possible to provide a more realistic solution for estimating the traffic light cycle.

  In particular, the travel information calculation device 100 provides a position range that is large enough to absorb GPS positioning errors, and when the measurement position is continuously detected within the position range, it is detected as a stop of the vehicle. Thereby, even if the accuracy of GPS is lower than that required by the technique disclosed in Patent Document 2, for example, the cycle of the traffic light can be estimated sufficiently accurately. In other words, a more versatile cycle estimation technique is provided that is not limited by GPS accuracy.

  Moreover, NS speed is calculated in the travel information calculation device 100 according to the present embodiment. This NS speed can be used in various systems to streamline vehicle traffic. For example, it can be used for selecting route information in car navigation as described above. When the driver travels on the NS route at the NS speed, the possibility that the driver can travel non-stop at the intersection increases. Thereby, the fuel consumption of the vehicle is improved. As a result, the driver's expense can be reduced and the load on the global environment can be reduced.

  Further, NS speed exceeding the speed limit is basically not used, and further, the driver does not get impatient so as not to be caught by a red light, and thus safe driving can be promoted.

  In addition, when there is a discrepancy between the currently acquired cycle and the stored cycle, travel information computing device 100 according to the present embodiment automatically updates the cycle. Therefore, it is possible to cope with new installation of traffic lights and change of control.

  Heretofore, the configuration and operation of the travel information calculation apparatus 100 according to the embodiment have been described. This embodiment is an exemplification, and it is understood by those skilled in the art that various modifications can be made to each component and combination of processes, and such modifications are within the scope of the present invention.

  In the embodiment, the case where the vehicle-mounted device of the automobile transmits a route request and receives the route information according to the route request has been described. However, the present invention is not limited to this, and the vehicle-mounted device of the vehicle receives NS speed information from the travel information computing device 100. And the vehicle-mounted device may generate an NS route based on the received NS speed information.

  In the embodiment, the case where the state in which the traffic light is in red is adopted as the state in which the traffic signal presents the stop instruction to the automobile is not limited to this, but the traffic light presents the stop instruction to the vehicle. The state may vary depending on, for example, the laws and regulations of each country.

  In the embodiment, the description has been given of the case where the travel information calculation device 100 first obtains the reference position of the stop and determines whether or not the reference position corresponds to the position of the traffic light. However, the present invention is not limited to this. The apparatus 100 may determine whether or not the traveling information is continuously present in a predetermined range around the position of the traffic light.

  2 navigation system, 20 network, 100 travel information calculation device, 102 travel information acquisition unit, 104 stop detection unit, 106 signal stop period acquisition unit, 108 calculation unit, 110 route information provision unit, 112 cycle update unit, 114 map information Holding unit, 116 Travel information holding unit, 118 Rearrangement information holding unit, 120 Stop period holding unit, 122 Pre-signal stop period holding unit, 124 Predicted cycle holding unit, 125 Actual measurement cycle holding unit, 126 NS speed holding unit

Claims (8)

A travel information acquisition unit that acquires travel information including a measured position of the vehicle and a measurement time from a communication device mounted on the vehicle via a network;
Based on the travel information acquired by the travel information acquisition unit, a stop detection unit that identifies a period during which the vehicle remains within a predetermined position range;
It is determined whether or not the position range corresponding to the period specified by the stop detection unit corresponds to the position of a known traffic signal, and if it is determined to correspond, the period specified by the stop detection unit is determined as the traffic signal. And a stop period acquisition unit that acquires as a period corresponding to the travel information calculation device.   The apparatus further includes a cycle calculation unit that calculates a period in which the traffic signal is in a state of presenting a stop instruction by combining a plurality of periods acquired by the stop period acquisition unit for a predetermined traffic signal. The travel information calculation device according to claim 1.   Based on the period calculated by the cycle calculation unit, the vehicle further includes a speed calculation unit that calculates a non-stop speed that is a speed at which a vehicle that has passed a certain traffic light can pass the next traffic light without receiving an instruction to stop. The travel information calculation device according to claim 2, wherein:   The travel information calculation device according to claim 3, wherein the speed calculation unit performs a predetermined discarding process on the non-stop speed when the calculated non-stop speed exceeds a legal speed limit.   A route generation unit that generates route information based on a non-stop speed calculated by the speed calculation unit when providing route information in a car navigation system mounted on a vehicle via a network is further provided. Item 5. The travel information calculation device according to item 3 or 4. A cycle holding unit for holding a period calculated by the cycle calculating unit in the past;
A period determination unit that determines consistency between a period acquired by the stop period acquisition unit and a corresponding past period held by the cycle holding unit;
The period update unit that updates the cycle holding unit according to the period acquired by the stop period acquisition unit when it is determined that the period determination unit does not match, the cycle update unit further comprising: The travel information calculation device according to any one of the above. Obtaining travel information including a measured position of the vehicle and a measurement time from a communication device mounted on the vehicle via a network;
Identifying a period during which the vehicle remains within a predetermined position range based on the acquired travel information;
Determining whether or not the position range corresponding to the identified period corresponds to the position of the known traffic signal, and if it is determined to correspond, obtaining the identified period as a period corresponding to the traffic signal; and A driving information calculation method comprising: A function of acquiring travel information including a measured position of the vehicle and a measurement time from a communication device mounted on the vehicle via a network;
A function for identifying a period during which the vehicle stays within a predetermined position range based on the acquired travel information;
Determining whether or not the position range corresponding to the identified period corresponds to the position of the known traffic signal, and if determined to correspond, a function of acquiring the identified period as a period corresponding to the traffic signal; and A computer program for causing a computer to realize the above.

Images