JP5101133B2 - Automated traveling vehicle and tracking system - Google Patents

Description

  The present invention relates to a tracking system and an automatic traveling vehicle applied to the tracking system.

2. Description of the Related Art Conventionally, there has been proposed an automatic following traveling system including a leading vehicle driven by a driver and a plurality of subsequent vehicles that automatically follow the leading vehicle and run in cascade (see, for example, Patent Document 1).
In Patent Document 1, the driving trajectory information of the leading vehicle and the driving operation amount such as the steering amount and the throttle opening degree are transmitted to the succeeding vehicle. In the succeeding vehicle, while referring to the trajectory information from the leading vehicle, It is disclosed that an operation amount that is paired with information is extracted, and the subsequent vehicle is driven using the extracted operation amount as a feedforward control amount.
JP 2000-113399 A

However, in the invention of the above-mentioned Patent Document 1, since the travel of the following vehicle is controlled using the operation amount of the leading vehicle as it is, there are the following various problems.
When a plurality of succeeding vehicles travel in a row following the lead vehicle, if one of the succeeding vehicles stops, there is a possibility that the succeeding vehicle traveling after the succeeding vehicle will collide.
If the road surface condition or the like changes after the leading vehicle passes, it becomes difficult to perform stable traveling.
When the vehicle characteristics are different, such as when the leading vehicle and the following vehicle are different, stable traveling cannot be realized.

  The present invention has been made to solve the above problems, and an object thereof is to provide an automatic traveling vehicle and a tracking system capable of realizing stable platooning.

In order to solve the above problems, the present invention employs the following means.
The present invention is an automatic traveling vehicle that automatically travels following a leading vehicle, and includes an acceleration means for detecting acceleration and a control means, and the control means is based on the acceleration detected by the acceleration means. The acceleration in the direction orthogonal to the traveling direction is obtained, the vehicle is decelerated when the acceleration in the direction orthogonal to the traveling direction exceeds a preset fourth threshold value, and the acceleration in the direction orthogonal to the traveling direction is previously determined. providing automatic traveling vehicle that be accelerated when it becomes less than the fifth threshold value that is set.

  According to such a configuration, the acceleration in the width direction is obtained, and the vehicle is decelerated and accelerated according to the acceleration. Therefore, when the leading vehicle is different from the leading vehicle, the centrifugal force and the traveling locus in the curve are different from the leading vehicle. However, stable running can be realized.

  The automatic traveling vehicle includes a communication unit that receives a travel locus and information on an operation amount from the leading vehicle, and the control unit calculates a turning radius in a curve from the traveling locus of the leading vehicle received by the communication unit. Detecting the turning radius of the curve that the user intends to travel from the travel locus and the operation amount, and decelerating when the turning radius of the curve that the user intends to travel is smaller than the turning radius of the leading vehicle It is good.

  In this way, the turning radius when traveling on the curve is compared with the turning radius of the leading vehicle when traveling on the curve, and the traveling speed is controlled according to the comparison result, so the vehicle type differs from the leading vehicle. Even when the centrifugal force and the traveling locus on the curve are different from those of the leading vehicle, stable traveling can be realized.

  The automatic traveling vehicle includes communication means for receiving position information of the leading vehicle, and environment recognition means for recognizing an environment in the vicinity of the traveling direction, and the control means includes the leading vehicle acquired by the communication means. Based on the position information and the environment in the vicinity of the traveling direction acquired by the environment recognition unit, a neighboring spatial region is developed into a map image, the presence or absence of an obstacle is determined based on the map image, and the determination result is The travel control may be performed accordingly.

  According to such a configuration, it is possible to recognize an obstacle that has entered the traveling locus of the leading vehicle. Thereby, it is possible to realize stable automatic traveling.

In the automatic traveling vehicle, comprising a rough road detecting means for detecting a rough road that exist on the travel locus of the leading vehicle, the control unit, when the rough road is detected by the rough road detecting means, be decelerated It is good.

  According to such a configuration, since the vehicle decelerates when a bad road is detected on the traveling locus of the leading vehicle, stable traveling can be realized.

In the automatic traveling vehicle , the rough road detecting means may determine that the road is a bad road when the acceleration detected by the acceleration sensor exceeds a preset threshold value.

  The automatic traveling vehicle further includes a position detection unit and a vehicle speed sensor, and the rough road detection unit calculates an apparent movement amount based on a vehicle speed pulse output from the vehicle speed sensor, and also detects the position detection. Calculating the actual movement amount based on the information from the means, and determining that the road is a bad road if the difference between the apparent movement amount and the actual movement amount is equal to or greater than a preset threshold value. Also good.

  The automatic traveling vehicle further includes a communication unit that receives an image of a road surface photographed by the leading vehicle, and an image acquisition unit that acquires a road surface in the vicinity of the front as an image, and the bad road detection unit includes the image acquisition unit. The uneven state of the road surface is detected based on the road surface image acquired by the means, and the uneven state is worse than the uneven state of the road surface detected based on the road surface image at the same position received from the leading vehicle. If it is, it may be determined that the road is bad.

  In the automatic traveling vehicle, when deceleration is performed by the control means, it may be notified to other vehicles.

  By notifying other vehicles that the vehicle has been decelerated, it is possible to perform flexible travel control corresponding to the deceleration also in other vehicles.
  Moreover, the said aspect can be utilized combining in the possible range.

  The present invention provides a tracking system including a leading vehicle and the above-described automatic traveling vehicle.

  According to another aspect of the present invention, an automatic traveling vehicle that automatically travels following a leading vehicle, and a distance measuring unit that measures an inter-vehicle distance from a preceding vehicle, and a traveling speed according to the inter-vehicle distance from the preceding vehicle. An automatic traveling vehicle comprising a control means for controlling the vehicle is provided.
  According to such a configuration, the traveling speed is controlled in accordance with the inter-vehicle distance from the preceding vehicle. For example, when the inter-vehicle distance becomes narrow, by controlling to stop the traveling, Collisions can be avoided. As a result, stable tracking traveling can be realized.
  Here, the front vehicle is a vehicle that is traveling immediately before the self-traveling vehicle. For example, when a plurality of self-traveling vehicles are traveling in series, the front vehicle is ahead of the front self-traveling vehicle. The vehicle is a leading vehicle, and the preceding vehicle with respect to the other autonomously traveling vehicles is the autonomously traveling vehicle that is traveling ahead.
  Further, in the automatic traveling vehicle, the control means decelerates when the inter-vehicle distance from the preceding vehicle becomes less than a preset first threshold, and the inter-vehicle distance is less than the first threshold. When the distance becomes smaller than the second threshold which is a small value, the vehicle stops traveling, and when the distance becomes equal to or larger than the third threshold which is equal to or larger than the second threshold and smaller than the first threshold, the traveling is started or resumed. It is good to do.
  According to such a configuration, it is possible to reliably avoid a collision with the preceding vehicle and to stop at a safe distance. In addition, when the vehicle distance is equal to or greater than the third threshold when the vehicle is stopped, the vehicle starts or restarts, so that stable autonomous driving can be realized.
  Further, in the automatic traveling vehicle, the control means sets a speed proportional to the inter-vehicle distance as a target speed when the inter-vehicle distance with the preceding vehicle is not less than a second threshold value and less than the first threshold value. Also good.
  According to such a configuration, when the vehicle approaches the vehicle ahead, the vehicle travels at a speed corresponding to the inter-vehicle distance, so that the vehicle can be stopped and started smoothly.

  The present invention is an automatic traveling vehicle that automatically travels following a leading vehicle, and includes communication means for receiving position information of the leading vehicle, environment recognition means for recognizing an environment in the vicinity of the traveling direction, and the communication means. Based on the acquired position information of the leading vehicle and the environment in the vicinity of the traveling direction acquired by the environment recognition means, a neighboring spatial region is developed into a map image, and the presence or absence of an obstacle is determined based on the map image. An automatic traveling vehicle is provided that includes a control unit that determines and performs traveling control according to the determination result.

  According to such a configuration, it is possible to recognize an obstacle that has entered the traveling locus of the leading vehicle. Thereby, it is possible to realize stable automatic traveling.

  In the automatic traveling vehicle, when deceleration is performed by the control means, it may be notified to other vehicles.

By notifying other vehicles that the vehicle has been decelerated, it is possible to perform flexible travel control corresponding to the deceleration also in other vehicles.
Moreover, the said aspect can be utilized combining in the possible range.

  The present invention provides a tracking system including a leading vehicle and the above-described automatic traveling vehicle.

  According to the present invention, there is an effect that stable row running can be realized.

Hereinafter, an embodiment of a tracking system and an autonomous vehicle according to the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 shows a schematic configuration of a tracking system according to an embodiment of the present invention.
As shown in FIG. 1, an automatic tracking traveling system 10 according to the present embodiment includes a leading vehicle 1 driven by a driver and subsequent vehicles 2 a and 2 b that travel following the leading vehicle 1. .
The following vehicles 2a and 2b are automatic traveling vehicles that automatically follow the leading vehicle 1 in a tandem state, in other words, a platoon. Here, although two succeeding vehicles 2a and 2b are shown, the number of succeeding vehicles in a column is not limited.

FIG. 2 shows a schematic configuration of the leading vehicle 1.
As shown in FIG. 2, the leading vehicle 1 includes a position detection unit 11 that detects a current position, an IMU (inertia measurement device) 12 for detecting the attitude of the vehicle, a vehicle speed sensor 13, and a steering actuator 14 for steering driving. , An accelerator / brake actuator 15 for operating the accelerator / brake, a communication device 16 for communicating with the following vehicle 2, a control device 17 and the like.
The position detection unit 11 includes, for example, a GPS antenna and a processing device that detects a position from information received by the GPS antenna.

  In the leading vehicle 1, the steering, accelerator, brake, and the like are operated by a person. Therefore, the operation amounts of the steering actuator 14 and the accelerator / brake actuator 15 corresponding to these operations are input to the control device 17. The running state is detected.

Specifically, various detection information from the position detection unit 11, IMU 12, and vehicle speed sensor 13 and an operation amount from the steering actuator 14 and the accelerator / brake actuator 15 are input to the control device 17. Yes. The control device 17 processes the input information with a Kalman filter, obtains a self-position based on the processed information, that is, the position, posture, speed, and steering angle of the leading vehicle 1, and creates a travel locus from the locus. . Furthermore, the control device 17 creates an operation amount table by associating each point on the travel locus with various operation amounts such as accelerator / brake and steering.
The travel locus and the operation amount table created by the control device 17 are transmitted to the succeeding vehicle 2 via the communication device 18.

FIG. 3 shows a schematic configuration of the following vehicles 2a and 2b.
As shown in FIG. 3, the following vehicles 2a and 2b include a position detection unit 21 that detects a current position, a camera 22 and an LRF (laser range finder) 23 for detecting a surrounding situation, and a vehicle speed sensor 24 that detects a vehicle speed. , IMU (Inertial Measurement Device) 25 for detecting the attitude of the vehicle, steering actuator 26 for steering driving as a driving mechanism for realizing autonomous traveling, accelerator / brake actuator 27 for accelerator / brake operation, and control of each part A control device (control means) 28 for communication, a communication device (communication means) 29 for performing communication with the leading vehicle 1, and the like.

  Information detected by various sensors such as the position detection unit 21, the camera 22, the LRF 23, the vehicle speed sensor 24, and the IMU 25 is input to the control device 28. The control device 28 drives and controls the steering actuator 26 and the accelerator / brake actuator 27 based on the information from these sensors and the travel locus and the operation amount table sent from the leading vehicle 1, thereby allowing the following vehicles 2a, 2b. Realize stable driving.

Here, for example, the control device 28 measures the distance to the vehicle ahead based on information input from the camera 22 and the LRF 23, and controls the traveling speed according to this distance. Specifically, the control device 28 controls the traveling speed according to a speed table as shown in FIG. In FIG. 4, the horizontal axis represents the inter-vehicle distance ΔL from the preceding vehicle, and the vertical axis represents the target speed of the following vehicles 2a and 2b.
Here, the front vehicle is a vehicle traveling in front, the front vehicle for the subsequent vehicle 2a is the leading vehicle 1, and the front vehicle for the subsequent vehicle 2b is the subsequent vehicle 2a.
Hereinafter, for the sake of brevity, control of the traveling speed in the succeeding vehicle 2b will be described as an example.

As can be seen from the speed table shown in FIG. 4, when the inter-vehicle distance ΔL with the following vehicle 2a that is the preceding vehicle is less than the dangerous distance L2 (second threshold), the control device 28 of the following vehicle 2b travels. Stop. When the inter-vehicle distance ΔL is equal to or greater than the danger distance L2 and less than the warning distance (first threshold value) L1, the control device 28 determines the speed represented by the following equation (1) as the target speed V, Feedback control is performed to achieve the target speed.
V = k (ΔL−L2) (1)
In the above equation (1), k is an arbitrary constant.

  When the inter-vehicle distance ΔL is equal to or greater than the warning distance L1, the control device 28 sets the target speed V based on the travel locus and the operation amount table received from the leading vehicle 1. Specifically, an operation amount corresponding to the self position detected by the position detection unit 21 is extracted from the operation amount table, and a target speed is set based on the extracted operation amount. As a method for setting the target speed, for example, a method described in JP 2000-113399 A can be adopted.

More specifically, the control device 28 of the following vehicle 2b sets the target speed V by performing the processing shown in FIG. 5 at a predetermined timing.
First, the control device 28 determines whether or not the inter-vehicle distance ΔL with the following vehicle 2a is equal to or greater than the warning distance L1. As a result, when the inter-vehicle distance ΔL is equal to or greater than the warning distance L1 (“YES” in step SA1), the operation amount of the leading vehicle 1 corresponding to the current position is extracted from the operation amount table, and based on the extracted operation amount. The target speed V is set and the vehicle travels at the target speed V (step SA2).
On the other hand, if the inter-vehicle distance ΔL is not greater than or equal to the warning distance L1 in step SA1, the process proceeds to step SA3 to determine whether the inter-vehicle distance ΔL is greater than or equal to the danger distance L2 and less than the warning distance L1. As a result, when the inter-vehicle distance ΔL is equal to or greater than the danger distance L2 and less than the warning distance L1 (“YES” in step SA3), the target speed V = k (ΔL−L2) is set. Traveling is performed (step SA3).
In step SA3, if the inter-vehicle distance ΔL is not greater than the danger distance L2 and less than the warning distance L1 (“NO” in step SA3), that is, if the inter-vehicle distance ΔL is less than the dangerous distance L2, step SA5 is performed. The following vehicle 2b is stopped. When the following vehicle 2a, which is the preceding vehicle, resumes traveling, and the inter-vehicle distance ΔL becomes greater than or equal to the danger distance L2 (“YES” in step SA6), the process proceeds to step SA7, and the target speed V = The traveling by k (ΔL−L2) is started.

Next, the operation of the tracking system 10 according to the present embodiment will be described.
First, when the driving of the leading vehicle 1 is started by driving by a person, various detection information is input to the control device 17 of the leading vehicle 1 from the position detection unit 11, the IMU 12, and the vehicle speed sensor 13, and the steering actuator. 14, the operation amount is input from the accelerator / brake actuator 15.

  Thereby, in the control apparatus 17, a current position is detected based on the input information from the position detection part 11, etc., and a traveling locus is created by taking the locus of this current position. Further, the operation amount is recorded at a predetermined distance interval, and the operation amount table is created by associating the operation amount with the position information. For example, in the operation amount table, the points A, B, C, D... Set on the traveling locus are associated with the operation amounts when passing through the points A, B, C, D. It has been.

  The travel locus and the operation amount table created by the control device 17 are transmitted to the following vehicles 2a and 2b via the communication device 16 at a predetermined timing, for example, a predetermined time interval or a predetermined distance interval. The information transmission timing here can be arbitrarily set. For example, when the following vehicles 2a and 2b have already started running, it is necessary to transmit periodically at a predetermined time interval, and after the leading vehicle 1 finishes running, the following vehicle 2 In the case of starting traveling, these data may be transmitted to the following vehicle 2 in a lump after the traveling of the leading vehicle 1 is completed.

When the succeeding vehicles 2a and 2b receive the traveling locus and the operation amount table from the leading vehicle 1, the following vehicles 2 track the leading vehicle 1 based on these information.
In the following vehicles 2a and 2b, the current position is detected by the control device 28 based on the input information from the position detection unit 21, and the surrounding situation is converted into a three-dimensional model based on the information from the camera 22 and the LRF 23. can get. Then, by setting its own target travel route based on these pieces of information, the vehicle travels along the travel trajectory that the leading vehicle 1 has passed, and is determined based on the operation amount table and the inter-vehicle distance ΔL with the preceding vehicle. By applying the manipulated amount to the steering actuator 26 and the accelerator / brake actuator 27, the automatic tracking traveling at the traveling speed based on the target speed V as described above is realized.

Next, the travel speed control performed in the following vehicles 2a and 2b will be specifically described. Here, for the sake of brevity, control of the traveling speed performed by the following vehicle 2b will be described with reference to FIG.
For example, as shown in FIG. 6, since the inter-vehicle distance ΔL with the following vehicle 2a that is the preceding vehicle is equal to or greater than the warning distance L1 at time t0, the control device 28 of the following vehicle 2b received from the leading vehicle 1 The operation amount corresponding to the current position is acquired from the operation amount table, and the traveling speed is controlled by setting the target speed V corresponding to the acquired operation amount.
As a result, during the period from time t0 to t1 in FIG. 6, the following vehicle 2b also travels through points A and B at the speed at which the leading vehicle 1 passes through the points A and B.

  Next, when the following vehicle 2a which is the preceding vehicle stops or decelerates for some reason, the inter-vehicle distance ΔL gradually decreases, and when the inter-vehicle distance ΔL becomes less than the warning distance L1 at time t1, the following vehicle 2b The control device 28 decelerates by setting k (ΔL−L2) as the target speed V. Thus, traveling at the target speed V corresponding to the inter-vehicle distance ΔL is performed during the period from time t1 to time t2 in FIG.

  Further, when the following vehicle 2a of the preceding vehicle stops and the inter-vehicle distance ΔL becomes less than the dangerous distance L2 at time t2, the control device 28 of the following vehicle 2b sets the target speed V to zero. Then, the traveling of the following vehicle 2b is stopped. Thereby, the following vehicle 2b will be in the stop state in the period from the time t2 of FIG. 6 to the time t3.

  Then, when the following vehicle 2a, which is the preceding vehicle, resumes driving and the inter-vehicle distance ΔL becomes greater than or equal to the danger distance L2 at time t3, the control device 28 of the following vehicle 2b sets the target speed V to k (ΔL−L2). ) Is set, the running speed is controlled according to the inter-vehicle distance ΔL. Thus, traveling at the target speed V corresponding to the inter-vehicle distance ΔL is performed in the period from time t3 to t4 in FIG.

  At time t4, when the inter-vehicle distance ΔL is equal to or greater than the warning distance L1, the control device 28 of the following vehicle 2b acquires the operation amount corresponding to the current position from the operation amount table received from the leading vehicle 1, and acquires the acquired operation. The running speed is controlled by setting a target speed V corresponding to the amount. Thereby, from time t4, the following vehicle 2b will also pass the points C and D at the speed when the leading vehicle 1 passes the points C and D.

As described above, according to the tracking system 10 and the automatic traveling vehicles 2a and 2b according to the present embodiment, the traveling speed is controlled according to the inter-vehicle distance ΔL with respect to the preceding vehicle. When it becomes narrower, it is possible to avoid a collision with the preceding vehicle by performing control to stop traveling. As a result, stable tracking traveling can be realized.
When the inter-vehicle distance ΔL is equal to or greater than the danger distance L2 and less than the warning distance L1, the vehicle travels at a target speed V = k (ΔL−L2) corresponding to the inter-vehicle distance ΔL. It can be done smoothly.

In the above-described embodiment, while the following vehicle is stopped, the travel is started or resumed when the inter-vehicle distance ΔL is equal to or greater than the danger distance L2, but the threshold for stopping the travel and the threshold for starting the travel It is good also as giving hysteresis to. For example, by setting the threshold value for starting the travel to the third threshold value that takes a value that is greater than or equal to the danger distance L2 and less than the warning distance L1, it is possible to more smoothly stop and restart the travel.
Further, in the above-described embodiment, the inter-vehicle distance ΔL with the preceding vehicle is obtained based on information acquired by the camera 21 and the LRF 22, but a distance measurement sensor or the like for measuring the distance is provided instead. Thus, the inter-vehicle distance ΔL may be detected.

[Second Embodiment]
Next, a tracking system according to the second embodiment of the present invention will be described.
For example, when a plurality of succeeding vehicles 2a and 2b travel in a row after the leading vehicle 1, there is a possibility that the road surface state of soil or the like may change due to the plurality of vehicles passing the same route. As a result, a difference occurs between the road surface state when the leading vehicle 1 passes and the road surface state when the rearmost succeeding vehicle passes, and it becomes difficult for the following vehicle to perform stable platooning.
In order to solve such a problem, in the present embodiment, the following configuration is provided. Note that the tracking system according to the present embodiment has substantially the same configuration as that of the first embodiment described above. Hereinafter, different points will be mainly described.

  First, in the tracking system according to the present embodiment, the control device 28 of the succeeding vehicles 2a and 2b includes a rough road detection function (bad road detection means) for detecting a bad road, and when a bad road is detected. Reduce the traveling speed or stop traveling. Here, the bad road refers to a road having a bad road surface condition such as a muddy road.

[Bad road detection method 1]
For example, the control device 28 detects a rough road based on a change in acceleration. For example, when the following vehicles 2a and 2b are provided with an acceleration sensor (not shown), and the acceleration detected by the control device 28 exceeds the preset threshold value, the road surface condition is deteriorated. Judge.

[Bad road detection method 2]
When the road surface condition is bad, the vehicle may slip. Therefore, the control device 28 detects a rough road by detecting the slip state of the vehicle body. Specifically, the control device 28 of the succeeding vehicles 2a and 2b apparently calculated based on the actual movement amount based on the current position detected by the position detection unit 21 and the vehicle speed pulse from the vehicle speed sensor 24. The movement amount is compared, and when the difference between the movement amounts exceeds a preset threshold value, it is determined that the vehicle is in the slip state. That is, it is determined that the road surface condition has deteriorated.
Instead of the above method, for example, the actual movement amount is obtained from the movement of the peripheral image acquired by the camera 22, and the actual movement amount is compared with the apparent movement amount calculated based on the vehicle speed pulse. However, when these differences exceed a preset threshold value, it may be determined that the vehicle is slipping, that is, the road surface condition has deteriorated.

[Bad road detection method 3]
The leading vehicle 1 is provided with a camera, and the state of the road surface through which the leading vehicle 1 passes is acquired as image information. And this image information is matched with the positional information detected by the position detection part 11, and is transmitted to the following vehicles 2a and 2b.
The control device 28 of the succeeding vehicles 2a and 2b compares the image information of the road surface in the traveling direction acquired by the camera 22 or the like that it has with the image information of the road surface of the same position acquired by the camera of the leading vehicle 1. If the road surface is uneven, it is determined that the road is rough.

  As described above, according to the tracking system and the automatic traveling vehicle according to the present embodiment, the road surface when the leading vehicle passes by passing the same route through a plurality of subsequent vehicles that run in a formation. Even if there is a difference between the state and the road surface state when the subsequent vehicle passes, the subsequent vehicle can perform stable platooning.

In the above-described embodiment, when deceleration or traveling is stopped due to detection of a bad road, the control device for the subsequent vehicle may transmit that fact to other subsequent vehicles and the leading vehicle. Good.
In this way, by notifying other vehicles that the vehicle has been decelerated or stopped due to a bad road, the leading vehicle can reduce the speed, for example, the traveling speed, in accordance with the following vehicle decelerated or stopped due to the bad road. It is possible to maintain the formation state by stopping or running. In addition, for a following vehicle that is running following a following vehicle that has been decelerated or stopped on a bad road, for example, a bad road is notified by notifying that the road surface condition has deteriorated and its position information. It is possible to suggest traveling that avoids the vehicle.

[Third Embodiment]
Next, a tracking system and an automatic traveling vehicle according to a third embodiment of the present invention will be described.
When the vehicle type of the leading vehicle is different from the vehicle type of the following vehicle, if the operation amount received from the leading vehicle is used as it is, a problem occurs in traveling.
For example, in the case of different types of vehicles, the vehicle weight, wheel suspension design, etc. may be different. In this case, when the vehicle travels according to the operation amount received from the leading vehicle, the centrifugal force, the travel locus, and the like are different in a curve or the like, which may make it difficult to perform stable travel.
In order to solve such a problem, in the present embodiment, the following configuration is provided. Note that the tracking system according to the present embodiment has substantially the same configuration as that of the first embodiment described above. Hereinafter, different points will be mainly described.

  In the present embodiment, the succeeding vehicles 2a and 2b are provided with acceleration sensors that detect acceleration, and the control device 28 obtains acceleration (centrifugal force) in the width direction (direction perpendicular to the traveling direction) from the detection result of the acceleration sensor. When the acceleration exceeds a preset fourth threshold, the vehicle decelerates, and when the acceleration falls below a fifth threshold that is smaller than the preset fourth threshold, the vehicle accelerates. (See FIG. 7).

  As described above, according to the tracking system and the automatic traveling vehicle according to the present embodiment, the acceleration in the width direction of the following vehicle is detected, and the vehicle is decelerated and accelerated according to this acceleration. Even if the vehicle type is different and the centrifugal force and the traveling locus on the curve are different, stable traveling can be realized.

The acceleration in the width direction is replaced by a method for measuring the amount of suspension displacement, for example, by providing a sensor for measuring the amount of suspension displacement, and calculating the amount of vehicle body tilt from the amount of suspension displacement of the wheel. The acceleration in the width direction may be obtained.
In addition, when the vehicle is decelerated due to the difference in the vehicle type described above, the subsequent vehicle may transmit information to that effect to other subsequent vehicles and the leading vehicle. As a result, the speed of all the vehicles that are traveling in a row can be flexibly changed.

Further, instead of the case where the traveling speed is controlled based on the acceleration in the width direction, for example, as shown in FIG. 7, the turning of the curve derived from the traveling locus received from the leading vehicle 1 by the control device of the succeeding vehicle is performed. Comparing the radius R with the target turning radius r when traveling on a curve based on the operation amount received from the leading vehicle 1, and when the target turning radius r is smaller than the turning radius R of the leading vehicle 1, It is good also as decelerating.
In this way, it is possible to eliminate the problem of platooning caused by the difference in the vehicle type between the leading vehicle and the following vehicle by controlling the traveling speed from the difference in the traveling locus when traveling on the curve. .

[Fourth Embodiment]
Next, a tracking system and an automatic traveling vehicle according to a fourth embodiment of the present invention will be described.
As described above, the tracking system of the present invention autonomously travels in accordance with the travel locus and the operation amount table received by the following vehicle from the leading vehicle, but after the leading vehicle passes, it moves on the traveling locus. If an obstacle enters the vehicle, the following vehicle cannot distinguish the obstacle from the leading vehicle.
For example, with an environment recognition sensor (environment recognition means) such as the camera 22 and the LRF 23 mounted on the following vehicles 2a and 2b shown in FIG. 3, it is difficult to distinguish the leading vehicle and the obstacle.

  In this case, for example, when the leading vehicle stops due to a failure or the like, the following vehicle may travel such that the leading vehicle is erroneously recognized as an obstacle and avoids the leading vehicle, and the formation of the train may be disturbed. . Further, when obstacle detection by the environment recognition sensor is not performed, the obstacle cannot be detected, and in the worst case, there is a possibility of colliding with the obstacle.

  In order to solve such a problem, in the present embodiment, the following configuration is provided. The tracking system and the automatic traveling vehicle according to the present embodiment have substantially the same configuration as that of the first embodiment described above. Hereinafter, different points will be mainly described.

  First, in the tracking system according to the present embodiment, the leading vehicle 1 periodically transmits the current position to the following vehicle. The control device 28 of the following vehicles 2a and 2b creates a surrounding two-dimensional or three-dimensional map image based on the detection information from the camera 12 and LRF 13 included in the vehicle, and on the two-dimensional or three-dimensional map image. The leading vehicle is written based on the current position received from the leading vehicle. At this time, as shown in FIG. 8, if a foreign object is detected on the map image at a position different from the leading vehicle, this foreign object is recognized as an obstacle and a traveling locus for avoiding the obstacle is set. To do. Moreover, the foreign material detected in the same position as the leading vehicle written on the map image is recognized as the leading vehicle.

  As described above, according to the tracking system and the automatic traveling vehicle according to the present embodiment, even when an obstacle enters the traveling locus of the leading vehicle, the subsequent vehicle determines whether to avoid or stop the obstacle. Can be done. As a result, it is possible to realize stable running while maintaining the formation state.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
Moreover, each embodiment mentioned above can be arbitrarily combined in the possible range.

It is the figure which showed schematic structure of the tracking system which concerns on the 1st Embodiment of this invention. It is the figure which showed schematic structure of the leading vehicle which concerns on the 1st Embodiment of this invention. It is the figure which showed schematic structure of the succeeding vehicle which concerns on the 1st Embodiment of this invention. It is the figure which showed an example of the speed table which the control apparatus of the succeeding vehicle shown in FIG. 3 refers. FIG. 4 is a flowchart of travel speed control executed by the control device for the succeeding vehicle shown in FIG. 3. It is the figure shown about the specific example of the traveling speed control performed by the control apparatus of the succeeding vehicle which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the difference in the turning radius of a curve in case the vehicle types of a leading vehicle and a succeeding vehicle differ. It is the figure which showed an example of the map image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Leading vehicle 2a, 2b Subsequent vehicle 10 Tracking system 21 Position detection part 22 Camera 23 LRF (laser range finder)
24 Vehicle speed sensor 25 IMU
26 Steering actuator 27 Accelerator / brake actuator 28 Control device 29 Communication device

Claims (9)

An automatic traveling vehicle that automatically travels following the leading vehicle,
Acceleration means for detecting acceleration;
Control means and
With
The control means includes
Based on the acceleration detected by the acceleration means, an acceleration in a direction orthogonal to the traveling direction is obtained, and when the acceleration in the direction orthogonal to the traveling direction is equal to or greater than a preset fourth threshold, the vehicle is decelerated. automatic traveling vehicle you acceleration when the acceleration in the direction perpendicular to the traveling direction is equal to or less than the fifth preset threshold. Comprising communication means for receiving a travel locus and information on an operation amount from the leading vehicle;
The control means detects the turning radius of the curve from the traveling locus of the leading vehicle received by the communication means, obtains the turning radius of the curve that the vehicle intends to travel from the traveling locus and the operation amount, and The automatic traveling vehicle according to claim 1, wherein the vehicle decelerates when a turning radius of a curve to be traveled is smaller than a turning radius of the leading vehicle. Communication means for receiving position information of the leading vehicle;
Environmental recognition means for recognizing the environment in the vicinity of the running direction,
The control means develops a nearby spatial region into a map image based on the position information of the leading vehicle obtained by the communication means and the environment in the vicinity of the traveling direction obtained by the environment recognition means, and the map The automatic traveling vehicle according to claim 1, wherein presence or absence of an obstacle is determined based on an image, and traveling control is performed according to the determination result. Including a rough road detecting means for detecting a rough road existing on a traveling locus of the leading vehicle;
The automatic traveling vehicle according to any one of claims 1 to 3, wherein the control means decelerates when a bad road is detected by the bad road detection means.   5. The automatic traveling vehicle according to claim 4, wherein the rough road detection unit determines that the road is a bad road when an acceleration detected by the acceleration sensor exceeds a preset threshold value. Position detecting means;
A vehicle speed sensor,
The rough road detection means calculates an apparent movement amount based on a vehicle speed pulse output from the vehicle speed sensor, calculates an actual movement amount based on information from the position detection means, and apparently The automatic traveling vehicle according to claim 4, wherein when the difference between the movement amount and the actual movement amount is equal to or greater than a preset threshold value, it is determined that the road is a rough road. Communication means for receiving an image of a road surface photographed by the leading vehicle;
Image acquisition means for acquiring a road surface near the front as an image;
The bad road detecting means detects the uneven state of the road surface based on the road surface image acquired by the image acquiring means, and the uneven state is detected based on the road surface image at the same position received from the leading vehicle. The automatic traveling vehicle according to claim 4, wherein it is determined that the road is rough when the road surface is worse than the uneven state of the road surface.   The automatic travel vehicle according to any one of claims 1 to 7, wherein when the vehicle is decelerated by the control means, the other vehicle is notified of the fact. A leading vehicle,
A tracking system comprising the automatic traveling vehicle according to any one of claims 1 to 8.

Images