JP2013186782A - Vehicle traveling track data recording device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a recording capacity for recording vehicle traveling track data, to lengthen a vehicle traveling track which can be recorded with a fixed recording capacity, to reduce data amounts to be transmitted from the vehicle, and to reduce data communication charge.SOLUTION: A steering angle detection part 15 detects the steering angle of a vehicle on the basis of the detection values of a steering angle sensor 5 or a wheel speed sensor 7. A steering angle change value detection part 17 calculates a change value per unit time of the vehicle steering angle. When the absolute value of the steering angle change value is relatively small, a data recording interval setting part 19 sets a data recording interval to be relatively long, and when the absolute value is relatively large, sets the data recording interval to be relatively short. When the data recording interval is reached, a recording control part 21 records a pair of the data of the vehicle position of a GPS 3 and the data of the vehicle steering angle in a recording device 13.

Description

  The present invention relates to a vehicle travel locus data recording apparatus and a vehicle travel locus data recording method for recording travel locus data of a running vehicle.

  Conventionally, traveling locus data collected by a traveling vehicle is transmitted to an external information center, and the traveling locus data transmitted from the information center is used to accurately grasp, for example, a road shape or detect a new road. A technique is known (for example, Patent Document 1).

  In Patent Document 1, when the steering angle of the steering wheel of the vehicle is large, when the lateral acceleration of the vehicle is large, or when the vehicle speed is low, it is considered that the vehicle is traveling on a curve, and a traveling locus is collected. A technique for setting a short interval is disclosed.

JP 2004-280521 A

  However, according to the technique described in Patent Document 1, since the interval for detecting the travel locus is shortened during the period when the vehicle is traveling on the curve, the travel locus data is increased, and thus the travel locus data is stored. Therefore, there is a problem that the storage capacity increases.

  An object of the present invention is to collect travel locus data at appropriate intervals even during a period in which the vehicle is traveling on a curve.

  In order to solve the above-described problems, the present invention provides a case where the calculated change value of the steering angle is small based on the vehicle position detected by the vehicle position detection unit and the steering angle detected by the steering angle detection unit. The vehicle recording position is stored in the recording device by setting the data recording interval longer than in the case where it is larger.

  According to the present invention, when the change value of the steering angle is large, the interval for storing the data becomes short, and when the change value of the steering angle is small, the interval for storing the data becomes long. Therefore, for example, even when the vehicle is traveling on a curve, if the vehicle is traveling at a substantially constant steering angle without changing the curve curvature, the change value of the steering angle is also small. The data recording interval is also increased, and the recording capacity for recording the vehicle travel locus data can be reduced.

It is a control block diagram explaining embodiment of the vehicle travel locus data recording device concerning the present invention. It is a flowchart explaining the processing content in embodiment. (A) It is a figure explaining the example of the vehicle travel locus data recorded in embodiment. (B) It is a figure explaining the example of the vehicle travel locus data recorded in the comparative example of a prior art. It is a control block diagram explaining the structure of the traffic information center which receives data from the vehicle travel locus data recording device based on this invention. It is a flowchart explaining the processing content of a traffic information center. It is a figure explaining the method of superimposing and collating a road shape and a several vehicle travel locus | trajectory, and estimating the traffic obstruction event on a road.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a control block diagram for explaining an embodiment of a vehicle travel locus data recording apparatus 1 according to the present invention. The vehicle travel locus data recording device 1 includes a GPS receiving device 3, a steering angle sensor 5, a wheel speed sensor 7, a control unit 9 using a microprocessor, a communication device 11, and a recording device 13. .

  The GPS receiver 3 is a device that receives radio waves from a satellite of the Global Positioning System and measures the position of the vehicle. In order to detect the position of the vehicle even when traveling in a tunnel or underground where GPS radio waves cannot be received, it is preferable to provide complementary devices such as a gyro sensor, an acceleration sensor and an integrator.

  The steering angle sensor 5 is a sensor that detects a steering angle signal of the steering and transmits it to the control unit 9. The wheel speed sensor 7 is a sensor that is provided on each wheel of the vehicle, detects a signal indicating the rotational speed of the wheel, and transmits the signal to the control unit 9.

  The control unit 9 is composed of a microprocessor in which a ROM storing a control program, a working RAM, an input / output interface, and a central processing unit are integrated on a single chip. And as a function which the control part 9 performs, the steering angle detection part 15, the steering angle change value detection part 17, the data recording interval setting part 19, and the recording control part 21 are provided, and these are performed by CPU. This is realized by a control program.

  The steering angle detector 15 detects the steering angle of the vehicle based on the detection signal of the steering angle sensor 5 or the detection signals of the left and right wheel speed sensors 7 of the front wheels that are steered wheels.

  When the vehicle steering angle is detected from the detection signal of the wheel speed sensor 7, the vehicle steering angle is calculated by calculation based on the ratio of the detected value of the other wheel speed sensor to the detected value of one wheel speed sensor of the left and right wheels. May be calculated, or a conversion table may be used.

  The steering angle change value detection unit 17 calculates a change value per unit time of the vehicle steering angle detected by the steering angle detection unit 15 and an absolute value of this change value.

  The data recording interval setting unit 19 sets an interval for recording vehicle position data as a variable interval instead of a fixed interval. That is, if the absolute value of the change value calculated by the steering angle change value detection unit 17 is relatively small, the data recording interval setting unit 19 sets the data recording interval relatively long, and the absolute value is relatively large. For example, the data recording interval is set relatively short. In order to obtain the data recording interval from the absolute value of the change value, a calculation formula may be used, or a conversion table stored in advance may be indexed to convert the absolute value of the change value into the data recording interval. At this time, if the absolute value of the change value is not in the conversion table, the change value is obtained from the table entries on the upper and lower sides of the absolute value of the change value using an interpolation method.

  When the data recording interval set by the data recording interval setting unit 19 is reached, the recording control unit 21 performs control to record the vehicle position data detected by the GPS receiving device 3 as the vehicle position detecting unit in the recording device 13.

  The recording device 13 uses a semiconductor storage device or a hard disk device to store the vehicle position data detected by the GPS receiver 3 and the vehicle steering angle data detected by the steering angle detector 15 in pairs. It is.

  The communication device 11 is a communication device for performing communication between the vehicle trajectory data recording device 1 and the traffic information center. For example, a third-generation mobile phone or a fourth-generation mobile phone is used. When the predetermined transmission timing is reached, the control unit 9 transmits the data on the plurality of vehicle positions and the data on the vehicle steering angle recorded in the recording device 13 to the traffic information center via the communication device 11. To do.

  FIG. 2 is a flowchart for explaining the contents of the control program executed by the control unit 9. First, in step S10, the current position of the vehicle by the GPS receiver 3 is detected. When traveling in a tunnel or underground where GPS satellite radio waves cannot be received, the current position of the vehicle is detected using the angular velocity detected by the gyro sensor, the value obtained by integrating the acceleration detected by the acceleration sensor twice, and the like.

  Next, in step S12, the vehicle steering angle is detected, a conversion value that is the difference between the previous vehicle steering angle and the current vehicle steering angle is calculated, and the absolute value of the change value is calculated. Next, in step S14, it is determined whether or not one of the exceptional conditions for not recording data is satisfied.

  Here, there are three exception conditions. The first exceptional condition is that the absolute value calculated in step S12 is not more than a predetermined value. The absolute value of the converted value of the vehicle steering angle being equal to or less than the predetermined value is a case where the vehicle is continuing in a straight traveling state or is continuing to turn at the same steering angle. Here, the predetermined value is set by experimentally obtaining steering play and fluctuation of the running locus during normal running.

  The second exceptional condition is that the vehicle speed is equal to or lower than a predetermined vehicle speed. The third exceptional condition is that the vehicle is moving backward. The second and third exceptional conditions are for not recording data when the vehicle is parked in a parking lot or the like.

  If it is determined in step S14 that the exception condition is satisfied, the process proceeds to step S22. In the same determination, if the exceptional condition is satisfied, the process proceeds to step S16.

  Next, in step S16, it is determined whether or not a time longer than the set recording interval has elapsed since the previous data was recorded, in other words, whether or not the elapsed time has reached the recording timing. If the recording timing has not been reached, the process proceeds to step S22. If it is determined in step S16 that the recording timing has been reached, the process proceeds to step S18.

  In step S18, the vehicle position data and the vehicle steering angle data are recorded in the recording device 13 as a pair.

  Next, in step S20, the data recording interval is updated according to the absolute value of the vehicle steering angle change value calculated in step S12. The relationship between the absolute value and the newly set data recording interval is such that if the absolute value is relatively small, the data recording interval is set relatively long, and if the absolute value is relatively large, the data recording interval is relatively Is set short. That is, if the steering operation amount or the wheel speed difference is relatively small, the vehicle steering angle changes relatively small, so that it is easy to restore the vehicle trajectory even if the data recording interval is relatively long. . Conversely, if the difference in steering operation amount or wheel speed is relatively large, the vehicle steering angle changes relatively large, so the data recording interval is set relatively short and the vehicle trajectory is accurately restored. be able to. Here, in order to convert the absolute value to the data recording interval, a predetermined calculation formula may be used, or a conversion table for converting the absolute value to the data recording interval may be used.

  Next, in step S22, it is determined whether or not the transmission timing from the vehicle to the traffic information center has been reached. If the transmission timing has not been reached, the process returns to step S10. If the transmission timing has been reached, the process proceeds to step S24, and a plurality of pairs of vehicle position data and vehicle steering angle data recorded in the recording device 13 are transmitted to the traffic information center via the communication device 11. . The transmission timing may be set when the passage of time reaches a predetermined transmission interval, or may be set to be the transmission timing when a predetermined number of data pairs are recorded in the recording device 13. Alternatively, it may be a timing when a transmission request is made from the traffic information center side.

  FIG. 3A is a diagram for explaining an example of vehicle travel locus data recorded in the present embodiment, and FIG. 3B is an example of vehicle position data according to a comparative example of the prior art. In the comparative example, as the curvature radius of the curve decreases, the interval decreases. On the other hand, in the embodiment, even if the curvature radius of the curve is reduced, the interval is not shortened while it is regarded as the same curvature radius.

  FIG. 4 is a block diagram illustrating the configuration of the traffic information center 51 that receives data from the vehicle travel locus data recording apparatus according to the present invention. The traffic information center 51 includes a communication device 23, a control unit 25, and a recording device 27. The communication device 23 is a device for communicating with a plurality of vehicles on which the vehicle travel locus data recording device 1 as shown in FIG. 1 is mounted. For example, a third generation mobile phone or a fourth generation mobile phone is used. Is.

  The recording device 27 is also a road shape database in which the vehicle travel locus data of each vehicle received by the control unit 25 via the communication device 23 is recorded and road shape data is recorded in advance. And according to the request | requirement of the control part 25, the vehicle running locus data and road shape data of each vehicle which were recorded can be read.

  The control unit 25 is a central unit that controls a traffic information center that estimates a traffic fault event on a road based on vehicle travel locus data received from a plurality of vehicles, and is configured using, for example, a personal computer or a server. Has been. The control unit 25 includes a trajectory restoration unit 29, a collation unit 31, a traffic fault event estimation unit 33, and a recording control unit 35.

  The trajectory restoration unit 29 restores two adjacent vehicle travel trajectories for each vehicle from the pair of the vehicle position data and the vehicle steering angle data for the vehicle trajectory data received from the vehicle. Thereby, the continuous vehicle travel locus | trajectory for every vehicle can be obtained with a small data amount.

  The collating unit 31 collates the road shape data read from the recording device 27 with the vehicle traveling trajectories restored by a plurality of vehicles. FIG. 6 is a diagram illustrating an example in which the vehicle travel locus indicated by AA ′ and the vehicle travel locus indicated by BB ′ are overlapped and collated with the road shape data of three lanes on one side. The traffic obstacle event estimation unit 33 estimates a traffic obstacle event on the road based on the result of the collation unit 31 collation.

  The recording control unit 35 records the vehicle travel locus data received from a plurality of vehicles in the recording device 27 and controls reading of the recorded vehicle travel locus data. The recording control unit 35 controls the reading of road shape data recorded in advance in the recording device 27.

  FIG. 5 is a flowchart for explaining the processing contents of the control unit 25 of the traffic information center 51. First, in step S <b> 30, vehicle travel locus data is received from a plurality of vehicles via the communication device 23. Here, it is assumed that each data of the vehicle travel locus data is composed of a pair of vehicle position data and vehicle steering angle data.

  Next, in step S <b> 32, the received vehicle travel locus data is recorded in the recording device 27 via the recording control unit 35. Next, in step S34, it is determined whether or not the number of recorded vehicle travel locus data, that is, the number of vehicles that have received the vehicle travel locus data is equal to or greater than a predetermined number. If it is less than the predetermined number, the process returns to S30. If it is determined in step S34 that the number is equal to or greater than the predetermined number, the process proceeds to step S36.

  In step S36, vehicle travel locus data is read from the recording device 27 for each vehicle, and the vehicle travel locus is restored from the read vehicle locus data. At the time of this restoration, two adjacent vehicle trajectories of the vehicle trajectory data are restored using the vehicle position data and the vehicle steering angle data. By sequentially shifting these two adjacent positions from the start point (first point in the data) to the end point (last point in the data) of the vehicle travel locus data, a continuous vehicle travel locus from the start point to the end point is obtained. Can be obtained.

  Next, in step S38, road shape data is read from the recording device 27, which is a road database. Next, in step S40, the vehicle travel trajectory for each vehicle restored in step S36 and the road shape data read in step S38 are overlapped and collated.

  Next, in step S42, it is estimated whether or not there is an event (traffic obstacle event) that causes a traffic obstacle on the road from the superposition of the vehicle travel locus for each vehicle and the road shape data. The traffic obstacle event is, for example, a fallen object on the road, a parked vehicle on the road, a faulty vehicle on the road, a vehicle stopped for control on the road, a traffic accident, or road construction.

  Referring to FIG. 6 again, the road trajectory indicated by AA ′ and the vehicle trajectory indicated by BB ′ both bypass C even though the road shape data indicates a straight road. , C can be estimated to be a traffic obstacle event. In FIG. 6, two vehicle travel loci are shown, but in practice, the accuracy of estimation can be improved by superimposing a larger number of vehicle travel loci.

  If it is not determined in step S42 that there is a traffic obstacle event, the process returns to step S30. If it is determined in step S42 that there is a traffic obstacle event, the process proceeds to step S44, and a message indicating that the traffic obstacle event has occurred is transmitted to each vehicle via the communication device 23 together with the location of occurrence. Return to S30.

  Each vehicle that has received the message transmitted in step S44 can know in advance that there is a traffic obstacle event ahead, so it is possible to select a detour route or change the lane in advance with a margin. . Therefore, there is an effect that it is possible to contribute to smooth traffic and safe traffic.

  According to the present embodiment described above, it is possible to record data of a vehicle travel locus that is longer than the conventional one in the same recording device capacity, or when recording data of a vehicle travel locus of the same distance, the capacity of the recording device can be small. There is an effect.

  Further, according to the present embodiment, there is an effect that the amount of data transmitted from the vehicle can be reduced and the data communication fee can be reduced.

  Further, according to the present embodiment, the steering angle detection unit detects the vehicle steering angle based on the detection value of the steering steering angle sensor that is originally provided in the vehicle. There is an effect that the vehicle steering angle can be detected without providing a simple sensor.

  Further, according to the present embodiment, the steering angle detection unit is based on the difference between the wheel speeds of the left and right wheels of the vehicle using the detection value of the wheel speed sensor used in the ABS that the vehicle is provided with as standard equipment. Since the vehicle steering angle can be calculated, there is an effect that the vehicle steering angle can be detected without providing an additional sensor for detecting the vehicle steering angle.

  Further, according to the present embodiment, if the absolute value of the change value of the vehicle steering angle is equal to or less than a predetermined value, the data of the vehicle position is not recorded even when the data recording interval is reached, so that the capacity of the recording device can be further reduced. In addition, there is an effect that the amount of data transmitted from the vehicle can be reduced and the data communication fee can be further reduced.

  Further, according to the present embodiment, if the vehicle speed is equal to or lower than the predetermined vehicle speed or the vehicle is moving backward, the vehicle position data is not recorded even when the data recording interval is reached, so that the capacity of the recording device can be further reduced. In addition, there is an effect that the amount of data transmitted from the vehicle can be reduced and the data communication fee can be further reduced.

  Further, according to the present embodiment, as the data, the vehicle position data and the vehicle steering angle data are recorded in the recording device as a pair, so that the traffic information center that has received the vehicle travel locus data from the vehicle determines the vehicle travel locus. There is an effect that it can be accurately restored.

DESCRIPTION OF SYMBOLS 1 Vehicle travel locus data recording device 3 GPS (vehicle position detection part)
DESCRIPTION OF SYMBOLS 5 Steering steering angle sensor 7 Wheel speed sensor 9 Control part 11 Communication apparatus 13 Recording apparatus 15 Steering angle detection part 17 Steering angle change value detection part 19 Data recording interval setting part 21 Recording control part

Claims (8)

Vehicle position detecting means for detecting the vehicle position;
Steering angle detection means for detecting the steering angle of the vehicle;
Steering angle change value calculating means for calculating a change value of the steering angle based on the vehicle position and the steering angle;
A data recording interval setting means for setting a data recording interval to be longer than when the calculated change value of the steering angle is small,
Data recording control means for storing the vehicle position in a recording device corresponding to the set data recording interval;
A vehicle travel locus data recording apparatus comprising:   2. The vehicle travel locus data recording apparatus according to claim 1, wherein the steering angle detection unit detects a steering angle of the vehicle based on a detection value of a steering angle sensor that detects a steering angle of the vehicle. .   2. The vehicle travel locus data recording apparatus according to claim 1, wherein the steering angle detection means detects a steering angle of the vehicle based on a turning angle of the vehicle.   2. The vehicle travel locus data recording apparatus according to claim 1, wherein the steering angle detection means calculates a steering angle of the vehicle based on a wheel speed difference between left and right wheels of the vehicle.   The data recording control means does not record the vehicle position even when the data recording interval is reached when the absolute value of the change value is equal to or less than a predetermined value. The vehicle travel locus data recording device described in 1.   6. The data recording control unit does not record a vehicle position even when the data recording interval is reached when the vehicle speed is equal to or lower than a predetermined vehicle speed or the vehicle is moving backward. The vehicle travel locus data recording device according to claim 1.   The vehicle travel locus data recording apparatus according to any one of claims 1 to 6, wherein the data recording control unit records the vehicle position and the steering angle as a pair. Based on the vehicle position detected by the vehicle position detection means and the steering angle detected by the steering angle detection means, the data recording interval is set longer than when the calculated change value of the steering angle is small. Then, the vehicle position is stored in a recording device.

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