JP4952566B2 - Congestion alleviation system - Google Patents

Description

  The present invention relates to a traffic jam alleviating system that mitigates traffic jams.

Conventionally, as a system for alleviating traffic jams, for example, when an arbitrary vehicle performs an avoidance operation, each subsequent vehicle is monitored by a sensor installed on the roadside, and an arbitrary vehicle avoidance operation is followed by each vehicle When the occurrence of traffic congestion is predicted by estimating the influence on the vehicle, it is known to send a deceleration instruction to the in-vehicle control device of the succeeding vehicle via the road-to-vehicle communication system (for example, patent document) 1).
JP 2000-306194 A

  However, in the conventional traffic jam mitigation system, there is a case where traffic jams cannot be mitigated because no specific deceleration instruction is given to the following vehicle. For example, when the first to third subsequent vehicles, which are subsequent vehicles, are traveling in succession after the leading vehicle, the deceleration amount of the first subsequent vehicle affects the deceleration amount of the second subsequent vehicle, and the second The deceleration amount of the following vehicle affects the deceleration amount of the third succeeding vehicle. Thus, traffic congestion is not alleviated because the effects of deceleration of the following vehicle ahead are propagated in an integrated manner.

  Accordingly, the present invention has been made to solve such a technical problem, and focuses on the propagation of deceleration between the following vehicles, and provides a traffic jam mitigation system that can reliably reduce traffic jams. Objective.

  That is, the present invention is a traffic jam alleviating system that reduces traffic jams in a vehicle. When it is determined that there is a traffic jam factor in the traffic jam judging unit and whether the traffic jam judging unit determines that there is a traffic jam factor, A deceleration unit that performs a deceleration control in advance on a plurality of subsequent vehicles viewed from an arbitrary vehicle heading for the factor generation point, and the deceleration unit has a distance from the congestion factor generation point that is greater than that of the first subsequent vehicle. The configuration is characterized in that the second succeeding vehicle far away is controlled to be decelerated with a deceleration amount smaller than the deceleration amount of the first succeeding vehicle.

  According to the present invention, it is determined whether or not there is a congestion factor, and when it is determined that there is a congestion factor, a subsequent vehicle of an arbitrary vehicle (preceding vehicle) heading to a point where the congestion factor occurs is determined. Deceleration control is performed, and in particular, for the second subsequent vehicle that is farther away from the congestion factor occurrence point than the first subsequent vehicle, the deceleration control is performed with a deceleration amount smaller than the deceleration amount of the first subsequent vehicle. Let In this way, for the second subsequent vehicle that is far from the congestion factor occurrence point, that is, for the second subsequent vehicle that has time to arrive at the congestion factor occurrence point, the congestion factor occurrence point By achieving the target speed to be achieved by the small deceleration amount before reaching the vehicle, the influence of the deceleration of the first subsequent vehicle on the second subsequent vehicle can be reduced. Therefore, the propagation of deceleration from the first succeeding vehicle to the second succeeding vehicle is suppressed, and the propagation of deceleration can be reduced with respect to the vehicle further behind the second succeeding vehicle. Accordingly, it is possible to reliably reduce traffic congestion.

  Here, in the traffic jam mitigation system, it is preferable that the deceleration means perform deceleration control with a smaller deceleration amount as the succeeding vehicle is farther from the traffic factor generation point.

By configuring in this way, it is possible to suppress the propagation of deceleration to the following vehicle in order from the leading vehicle side, so that the following vehicle farther from the congestion factor occurrence point has a slower speed change, and the convergence of deceleration propagation is improved. By improving, traffic congestion can be relieved reliably. Further, the deceleration means may cause the second succeeding vehicle to perform deceleration control with the deceleration amount so as to achieve a target speed to be achieved before reaching the congestion factor occurrence point.

  According to the present invention, attention can be paid to the propagation of deceleration between the following vehicles, and the traffic jam can be reliably reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

(First embodiment)
The traffic congestion mitigation system according to the first embodiment is a system that accelerates and decelerates a vehicle to mitigate traffic congestion, and is preferably employed at a point where traffic congestion is likely to occur, such as a vehicle merging point on a road. is there.

  First, the configuration of the traffic jam mitigation system according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a traffic jam alleviating system according to an embodiment of the present invention.

  A traffic jam mitigation system 1 shown in FIG. 1 includes a plurality of vehicles 2R (R: character string) having the same configuration, and a roadside communication device 3 that provides information related to traveling to these vehicles 2R.

  First, the configuration of the vehicle 2R will be described. The vehicle 2R is, for example, a vehicle having an automatic driving function, and includes an ECU (Electronic Control Unit) 20, an actuator 23, and a display unit 24. Here, the ECU 20 is a computer of an electronically controlled automobile device, and includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output interface, and the like. The ECU 20 includes a communication control unit 21 and an acceleration / deceleration control unit 22. In the following, considering ease of understanding, the vehicle 2N that is one of the plurality of vehicles 2R is used as a reference, and vehicles 2R other than the vehicle 2N are expressed as vehicles 2M (M ≠ N). I will explain.

  The communication control unit 21 of the vehicle 2 </ b> N has a function of performing vehicle-to-vehicle communication that communicates with another vehicle 2 </ b> M and road-to-vehicle communication that communicates with the roadside communication device 3. Specifically, the communication control unit 21 of the vehicle 2N performs, for example, travel information such as the vehicle speed of the vehicle 2M, vehicle specification information such as the vehicle length of the vehicle 2M, and the vehicle 2M in the inter-vehicle communication with the vehicle 2M. A function of receiving recognized road information and traffic information, information received when the vehicle 2M communicates with the roadside communication device 3, and information related to travel control of the vehicle 2M, for example, acceleration / deceleration amount information of the vehicle 2M. It has the function to transmit. Further, the communication control unit 21 of the vehicle 2N receives, for example, information related to travel control of the vehicles 2N and 2M, specifically, acceleration / deceleration amount information of the vehicles 2N and 2M from the roadside communication device 3 in road-to-vehicle communication. And a function of transmitting the travel information and vehicle specification information of the vehicle 2M received by the inter-vehicle communication to the roadside communication device 3 in addition to the travel information such as the vehicle speed of the vehicle 2N and the vehicle specification information such as the vehicle length. Have. Furthermore, the communication control unit 21 has a function of outputting the acceleration / deceleration amount information of the vehicle 2N received from the roadside communication device 3 to the acceleration / deceleration control unit 22 and the display unit 24.

  The acceleration / deceleration control unit 22 has a function of generating a signal for controlling the actuator 23 based on the acceleration / deceleration amount information of the vehicle 2N output from the communication control unit 21. The acceleration / deceleration control unit 22 has a function of outputting the generated control signal to the actuator 23. The actuator 23 is a mechanical component that controls the traveling of the vehicle 2, and is, for example, an electronic throttle that performs acceleration control, a hydraulic brake that performs deceleration control, or the like. The actuator 23 has a function of controlling vehicle travel based on a control signal output from the acceleration / deceleration control unit 22.

  The display unit 24 has a function of notifying the driver of the acceleration / deceleration amount information of the vehicle 2N output from the communication control unit 21. For example, a display device is used. The display unit 24 may be provided as necessary in consideration of the performance required for the vehicles 2N and 2M.

  Next, the configuration of the roadside communication device 3 will be described. The roadside communication device 3 has a function of communicating with the vehicle 2R that is disposed on the roadside and passes through a point where the roadside communication device 3 is disposed. For example, an optical beacon having a bidirectional communication function is used. The roadside communication device 3 includes a communication control unit 30, a traffic jam determination unit 31, and an acceleration / deceleration amount calculation unit 32.

  The communication control unit 30 has a function of performing road-to-vehicle communication that communicates with the vehicle 2 </ b> R and road-to-road communication that communicates with other roadside communication devices 3. Here, assuming that the vehicle 2N is a vehicle that passes a point where the roadside communication device 3 is disposed, a function of performing road-to-road communication will be specifically described. The communication control unit 30 receives information related to travel control of the vehicle 2N to be communicated and the other vehicle 2M, for example, acceleration / deceleration amount information of the vehicles 2N and 2M output from the acceleration / deceleration amount calculation unit 32 described later. It has a function to transmit to. Further, the communication control unit 30 has a function of receiving, from the vehicle 2N, traveling information such as vehicle speeds of the vehicles 2N and 2M, vehicle specification information such as the vehicle length, and the like. Further, the communication control unit 30 has a function of sharing traffic information including road speed and position information and road information with other roadside communication devices 3 by performing road-to-road communication. Furthermore, the communication control unit 30 has a function of storing information received from the vehicle 2N, traffic information shared with other roadside communication devices 3, and road information in a memory included in the roadside communication device 3.

  The traffic jam determination unit 31 has a function of referring to the traffic information and road information stored in the memory by the communication control unit 30 and determining whether there is a traffic jam factor on the road on which the vehicle 2N travels. In addition, the traffic jam determination unit 31 has a function of outputting a determination result as to whether there is a traffic jam factor to the acceleration / deceleration amount calculation unit 32.

  The acceleration / deceleration amount calculation unit 32 inputs the determination result output from the traffic jam determination unit 31, and in the case of the determination result that there is a traffic jam factor, traffic information and road information stored in the memory by the communication control unit 30 , The acceleration / deceleration amounts of the vehicles 2N and 2M are calculated, and the acceleration / deceleration information based on the calculated acceleration / deceleration amounts is output to the communication control unit 30.

  Next, the operation of the traffic jam mitigation system 1 according to this embodiment will be described. FIG. 2 is a sequence diagram showing the operation of the traffic jam mitigation system 1 according to the present embodiment, FIG. 3 is a flowchart showing the operation of the roadside communication device, and FIG. 4 is a flowchart showing the operation of the vehicle. The sequence is described in time series from the top to the bottom of the drawing.

  First, the operation | movement outline | summary of the traffic congestion alleviation system 1 is demonstrated using FIG. In consideration of the ease of understanding, the operation of the congestion mitigation system 1 will be described using the road and traffic state shown in FIG. FIG. 5 is an example of a traffic state at a point where traffic congestion is likely to occur, and is a schematic diagram for explaining the operation of the traffic congestion mitigation system.

  The roadside communication device 3 of the traffic jam mitigation system 1 shares information with other roadside communication devices 3 at a predetermined interval by the roadside communication function of the communication control unit 30 (FIG. 2A). For example, the roadside communication device 3A installed on the two-lane main road shown in FIG. 5 shares traffic information, road information, and the like with the roadside communication device 3B installed on the road joining the main road. The shared information is stored in the memory of the roadside communication device 3, for example.

  Further, the vehicle 2N shares information with the nearby vehicle 2M at a predetermined interval by the inter-vehicle communication function of the communication control unit 21 (FIG. 2A). For example, traffic information and road information are shared between the vehicles 2A to 2E traveling on the main road shown in FIG.

  Under such circumstances, the roadside communication device 3 checks whether or not there is a vehicle passing through the installation point of the roadside communication device 3 at a predetermined interval. For example, when near-infrared light is projected onto the road near the point where the roadside communication device 3 is installed and the vehicle 2N enters the projected range (FIG. 2B), the roadside communication device 3 Information on the vehicle side is requested from the vehicle 2N (FIG. 2C). In response to the request, the vehicle 2N transmits vehicle-side information to the roadside communication device 3 (FIG. 2D). The roadside communication device 3 performs a calculation process based on the received vehicle-side information and information that the other roadside communication devices have, and transmits the calculated travel information to the vehicle 2N (FIG. 2 (e)). The vehicle 2N performs a travel control process based on the received travel information and transmits the received travel information to the vehicle 2M, and the vehicle 2M sequentially transmits the received travel information to surrounding vehicles 2M (FIG. 2 ( f)).

  As described above, in the driving support system 1, the roadside communication device 3 and the vehicle 2N communicate with each other, and information is transmitted from the vehicle 2N to the vehicle 2M, thereby performing travel control of the entire vehicle 2R.

  Next, the operation of the roadside communication device 3 will be described in detail with reference to FIG. The control process in FIG. 3 is repeatedly executed at a predetermined timing, for example.

  First, the congestion determination unit 31 of the roadside communication device 3 performs a congestion factor determination process (S10). In the process of S10, the traffic jam determination unit 31 predicts a factor causing traffic jam based on the traffic information and road information stored in the memory, and determines whether there is a traffic jam factor.

This will be specifically described below with reference to FIG. In FIG. 5, the vehicles 2A to 2E travel on the main road where the junction point P exists toward the junction point P, and the vehicle 4A travels on the junction road joining the main road toward the junction point P. Yes. Here, considering the ease of understanding, the speeds V _2A , V _2B , V _2C , V _2D , V _{2E of} the vehicles 2A, 2B, 2C, 2D, 2E and the speed V 4A of the vehicle _4A are the same, It is assumed that the vehicle length L _CAR of the vehicles 2A to 2E and the vehicle 4A is the same, the inter-vehicle distance X between the vehicles 2A to 2E is the same, and the minimum inter-vehicle distance X _MIN necessary for ensuring safety is the same. In addition, for example, a merge point, an intersection, and the like are set in advance as traffic congestion factor generation points where traffic congestion may occur and are included in the road information. The vehicles 2A to 2C have already passed the installation point of the roadside communication device 3A on the main road, and when the vehicle 2D passes the installation point of the roadside communication device 3A, the roadside communication device 3B of the joining road Assume that 4A is detected.

In such a case, the traffic jam determination unit 31 recognizes the traffic jam factor occurrence point from the road information, and also acquires the position, speed pattern (time change of V _4A ) of the vehicle 4A acquired through the roadside communication device 3B, the vehicle length. L _CAR , necessary inter-vehicle distance X _MIN , current position of vehicle 2A to vehicle 2E acquired from vehicle 2D, speed pattern (changes in V _2A , V _2B , V _2C , V _2D , and V _2E over time), vehicle length Based on L _CAR , necessary inter-vehicle distance X _MIN, or the like, at the junction point (congestion factor generation point) P, the vehicle 4A that merges and the vehicles 2A to 2E collide, or the vehicle 4A that merges Is calculated whether there is a vehicle whose inter-vehicle distance is equal to or less than the safe inter-vehicle distance _XMIN . When it is predicted that there is no vehicle to be subjected to deceleration control, the traffic jam determination unit 31 determines that there is no traffic jam factor and ends the control process illustrated in FIG. On the other hand, when it is predicted that there is a vehicle to be subjected to deceleration control, it is determined that there is a congestion factor, and the process proceeds to a deceleration amount calculation process (S12).

The process of S12 is a process executed by the acceleration / deceleration amount calculation unit 32 to calculate the acceleration / deceleration amount W of the vehicle 2R. First, the acceleration / deceleration amount calculation unit 32 determines a time at which a congestion factor occurs. The time at which the vehicle 4A as shown in FIG. 5 reaches the merging point P, when the vehicle 2A~ vehicle 2E also arrive at the confluence point P is the time is the congestion factor generation time T _b. Then, the acceleration / deceleration amount calculation unit 32 defines, for example, the vehicle that arrives at the congestion factor occurrence point earliest after the time of occurrence of the congestion factor among the vehicles 2A to 2E as the leading vehicle, and follows the leading vehicle. Define the vehicle as the following vehicle. Here, in the case shown in FIG. 5, it is assumed that the vehicle 2A is the leading vehicle and the vehicles 2B to 2E are the following vehicles. When the leading vehicle is determined, the acceleration / deceleration amount calculation unit 32 determines the deceleration amount of the leading vehicle. Here, for performing road-vehicle communication is vehicle 2D is a following vehicle, as described in FIG. 2, the vehicle 2A is a top vehicle, it is possible to know the collision time T _b by inter-vehicle communication , the time that the vehicle 2A is aware of the collision occurrence time _{T b} and the recognition time _{T a.} Then, in order to securely joins the vehicle 4A, the distance L _a to advance between times T _b vehicle 2A from the time T _a is expressed by the following equation (1).

For example, the time _{T a} to the reference (0 s), after 4s the time _{T b,} the vehicle speed _{V 4A} to 90 km / h, the vehicle length _{L CAR} to 5 m, a minimum inter-vehicle distance _{X MIN} and 20 m, should the vehicle 2A travels distance L _a is a 75m using equation (1). After calculating the distance _{L a} to the vehicle 2A proceeds, then, it obtains the deceleration _{a 2A} required vehicle 2A. The deceleration amount a _2A is obtained by the following equation (2).

For example, the vehicle speed _{V 2A} is 90 km / h in the same and the vehicle speed _{V 4A,} the distance _{L a} to the vehicle 2A progresses to 75 m, the deceleration _{a 2A} becomes -3.125m / ^{s 2.} Therefore, the vehicle speed _{V 2A} of the vehicle 2A at the time of confluence 45km / h, and this value becomes the minimum speed _{V 2A_MIN} vehicle 2A.

Since the vehicle 2A is controlled to decelerate when the vehicle 4A joins, the vehicle 2A needs to be accelerated to return to the initial vehicle speed of 90 km / h and the normal inter-vehicle distance of 30 m in order not to cause congestion. Assuming that the vehicle 2A accelerates immediately after joining the vehicle 4A, the acceleration b _2A necessary for returning to the normal state is obtained by the following equation (3).

For example, if the inter-vehicle distance X is 30 m, the required acceleration b _2A is 7.8 m / s ² using Equation 3. In equation (3), the speed V _4A and the speed V _2A are equal, and for convenience, the speed V _4A is substituted into the speed V _2A and displayed. The time T _{c at} which the vehicle 2A returns to the normal traveling state using the acceleration calculated using the equation (3) is expressed by the following equation (4).

For example, when the acceleration is 7.8 m / s ² , the time T _c is 5.6 s after Equation (4). When the time T _c is obtained, the distance X _a that the vehicle 2A travels between the time T _a and the time T _c can be expressed by the following equation (5).

Thereby, for example, it can be predicted that the vehicle A is traveling about 105 m from time _Ta to time _Tc . In formula (4), the speed V _4A and the speed V _2A are equal, and for convenience, the speed V _4A is substituted into the speed V _2A and displayed.

After calculating the distance _{X a} and the time _{T c} vehicle 2A of the leading vehicle advances, the vehicle 2B~2E the following vehicle, after time _{T c} obtained, the following distance X and the vehicle speed _{V 2B, V 2C, V 2D} , V Deceleration and acceleration are set to satisfy _2E . Here, in particular, the succeeding vehicle is set so that the deceleration amount W becomes smaller as the vehicle is farther from the congestion factor occurrence point. That is, the deceleration amount _{W 2C} vehicle 2C than deceleration amount _{W 2B} of the vehicle 2B is small, the vehicle 2D deceleration amount _{W 2D} is set smaller than the reduction amount _{W 2B} of the vehicle 2C.

The setting of the deceleration amount W will be described in detail. Deceleration amount W is set based on the deceleration _{a n} vehicles 2B~2E the following vehicle. For example, the vehicle 4A to be merged is the first, and the vehicles 2A to 2E that accept the merge are the second, third, fourth,. Then, the distance from the joining point P when the joining vehicle 4A is recognized is X _4A , and the distance from the joining point P when the nth vehicle (n ≧ 2) that accepts the joining recognizes the joining vehicle 4A. _Xn , the vehicle length of each vehicle is not uniform, Ln is the vehicle length of the _nth vehicle, Vn is the vehicle speed when the _nth vehicle that receives the merge recognizes the merged vehicle 4A, Vn Assuming that the time required from the time when the nth vehicle that accepts the merged vehicle 4A to the time when the merged vehicle 4A reaches the merged point P is T, the deceleration a _n of the _nth vehicle that accepts the merge is It can be expressed by equation (6).

The equation (6), to determine the deceleration _{a n} of each following vehicle 2B-2E, to determine the deceleration amount W of the following vehicle 2B-2E on the basis of the deceleration _{a n.} When the process of S12 ends, the process proceeds to a transmission process (S14).

  The process of S14 is a process which the communication control part 30 performs and transmits the deceleration amount W of the vehicle 2R to the vehicle 2N. For example, the deceleration amount W of the vehicles 2A to 2E generated by the process of S12 is transmitted to the vehicle 2D shown in FIG. As a result, the vehicle 2N can know the occurrence of the traffic jam factor in advance, that is, before judging that the brake is stepped on visually while driving normally. When the process of S14 ends, the control process shown in FIG. 3 ends.

  Thus, the operation of the roadside communication device 3 ends. Next, the operation of the vehicle 2R will be described in detail with reference to FIG. The control process of FIG. 4 is repeatedly executed at a predetermined timing, for example.

  First, the communication control unit 21 of the vehicle 2R starts from an acceleration / deceleration amount reception process (S20). In the process of S20, the communication control unit 21 receives the acceleration / deceleration amount W of the host vehicle through road-to-vehicle communication or vehicle-to-vehicle communication. For example, in the case shown in FIG. 5, the deceleration amount W is received from the roadside communication device 3 in the case of the vehicle 2D, and the vehicle 2D is transmitted by inter-vehicle communication in the case of the vehicles 2A to 2C and 2E. The deceleration amount W is received directly or via another vehicle. When the process of S20 ends, the process proceeds to an acceleration / deceleration process (S22).

The process of S22 is a process of performing vehicle control based on the acceleration / deceleration amount received by the process of S20, which is executed by the acceleration / deceleration control unit 22. For example, the acceleration / deceleration control unit 22 generates a speed pattern from the acceleration / deceleration amount, and controls the actuator 23 along the generated speed pattern. For example, as shown in FIG. 5, a time-dependent speed pattern (FIGS. 5A to 5D) is generated for each of the vehicles 2B to 2D, and each vehicle has an actuator 23 based on the speed pattern. Control. In the speed pattern shown in FIG. 5, the deceleration timing is the earliest timing of the vehicle 2D (time T _2D ), and the deceleration timing is generated in order toward the leading vehicle. When the process of S22 ends, the control process shown in FIG. 4 ends.

  As described above, by performing the processing shown in FIG. 3 and FIG. 4, in the subsequent vehicle following the leading vehicle, the subsequent vehicle far behind the point where the congestion factor occurs is set to a smaller deceleration amount, so that the following vehicle behind On the other hand, the propagation of deceleration can be suppressed, and as a result, the traffic jam can be reduced.

  Next, the effect of this embodiment is demonstrated using FIG. FIG. 6 is a schematic diagram showing an example in which the traffic congestion mitigation system according to the present embodiment is applied, showing time-series traffic conditions in the order of (a) to (g), where (a) is 0 second. , (B) after 1 second, (c) after 2 seconds, (d) after 3.8 seconds, (e) after 4.3 seconds, (f) after 6 seconds, (g) after 7 seconds It shows the traffic condition after 6 seconds.

  As shown in FIG. 6A, when two roads merge at a junction P, it is assumed that roadside communication devices 3A and 3B are arranged on the respective roads. On the road where the roadside communication device 3A is arranged, the three vehicles 2A to 2C are traveling (cruising state) toward the junction P while maintaining the inter-vehicle distance of 30 m at a speed of 90 km / h. It is assumed that the vehicle 4A is traveling toward the joining point P at a speed of 90 km / h on the arranged road. The length of each vehicle is 5 m. In addition, when the vehicle 2C passes the installation point of the roadside communication device 3A, the vehicle 4A also passes the installation point of the roadside communication device 3B. Then, the roadside communication device 3B transmits information indicating that the vehicle 4A is heading to the joining point P to the roadside communication device 3A, and the roadside communication device 3A receives the information transmitted by the roadside communication device 3B. Further, the vehicle 2C transmits the current vehicle speed of the vehicles 2A and 2B that have passed through the roadside communication device 3A to the roadside communication device 3A, and the roadside communication device 3A receives the information transmitted by the vehicle 2C. Then, it is determined whether or not the vehicles 2A and 2B collide with the vehicle 4A. In the example shown in FIG. 6, it is determined that the vehicle 2 </ b> A collides when traveling as it is. Then, the roadside communication device 3A calculates the deceleration amount W of the vehicles 2A to 2C and transmits it to the vehicle 2C. When the vehicle 2C receives the deceleration amount W from the roadside communication device 3A, the vehicle 2C generates a speed pattern based on the deceleration amount W, starts a deceleration process, and decelerates the vehicles 2A and 2B by inter-vehicle communication with respect to the vehicle 2B. The amount W is transmitted (FIG. 6B). By this operation, the vehicle 2C becomes 89 km / h.

  Then, the vehicle 2B receives the deceleration amount W from the vehicle 2C, generates a speed pattern based on the received deceleration amount, starts a deceleration process, and transmits the deceleration amount W of the vehicle 2A to the vehicle 2A through inter-vehicle communication. Is transmitted (FIG. 6C). Since the deceleration amount of the vehicle 2B is larger than the deceleration amount of the vehicle 2C, the vehicle 2C is 87 km / h and the vehicle 2B is 85 km / h in FIG.

  Then, the vehicle 2A receives the deceleration amount W from the vehicle 2B, generates a speed pattern based on the received deceleration amount, and starts a deceleration process (FIG. 6D). Since the deceleration amount of the vehicle 2A is larger than the deceleration amount of the vehicle 2B, the vehicle 2C is 84 km / h, the vehicle 2B is 78 km / h, and the vehicle 2A is 69.75 km / h in FIG.

  Next, at the time shown in FIG. 6 (e), the vehicle 2C changes from deceleration control to acceleration control, the vehicle speed becomes 85 km / h, the vehicles 2B and 2A maintain the deceleration control, and the vehicle 2B maintains 74 km / h. h, the vehicle 2A is 64.125 km / h.

  Next, at the time shown in FIG. 6 (f), the vehicle 2C has a vehicle speed of 87 km / h by acceleration control, and the vehicle 2B has been changed from deceleration control to acceleration control, and the vehicle speed has become 80 km / h. Maintains deceleration control and becomes 45 km / h. Then, the vehicle 4A joins from the merge lane while maintaining 90 km / h in front of the vehicle 2A. At this time, the inter-vehicle distance between the vehicle 4A and the vehicle 2A is smaller than the initial inter-vehicle distance of 30 m between the vehicle 2A and the vehicle 2C, and is 20 m, which is the minimum inter-vehicle distance that ensures safety, and is in the closest state.

  Next, at the time shown in FIG. 6 (g), the vehicle speed becomes 90 km / h by the vehicle 2C, 2B acceleration control, and the vehicle 2A changes from deceleration control to acceleration control, and the vehicle speed becomes 90 km / h. The inter-vehicle distance between the vehicles 2A to 2C is 30 m, and the inter-vehicle distance between the vehicle 4A and the vehicle 2A is 30 m. Thereafter, the vehicles 2A to 2C and the vehicle 4A are in a cruise state.

  As described above, according to the traffic jam mitigation system 1 of the first embodiment, it is determined whether or not there is a traffic jam factor. If it is determined that there is a traffic jam factor, the vehicle following the vehicle 2A heading for the traffic jam factor generation point P Deceleration control is performed on a certain vehicle 2B to 2D, and in particular, for a vehicle 2C or vehicle 2D that is farther away from the congestion factor occurrence point than the vehicle 2B, the deceleration is smaller than the deceleration amount W of the vehicle 2B. Deceleration control is performed with the amount W. In this way, for the vehicle 2C or the vehicle 2D that is far from the congestion factor occurrence point P, that is, for the vehicle 2C or the vehicle 2D that has time to arrive at the congestion factor generation point P, the congestion factor By achieving the target speed to be achieved before reaching the generation point P with a small deceleration amount, the influence of the deceleration of the vehicle B that the vehicle 2C or the vehicle 2D receives can be reduced. Therefore, the propagation of deceleration from the vehicle B to the vehicle 2C or the vehicle 2D is suppressed, and the propagation of deceleration can be reduced with respect to the vehicle further behind the vehicle 2C or the vehicle 2D. Accordingly, it is possible to reliably reduce traffic congestion.

  In addition, when acceleration / deceleration control is performed during normal traveling, that is, when acceleration / deceleration control is performed by visually recognizing danger or the necessity of merging, the occurrence of a congestion factor can be known at an earlier timing. As a result, a large time margin until arrival at the congestion factor occurrence point P can be secured, so that the target speed to be achieved before arrival at the congestion factor generation point P can be achieved with a smaller deceleration amount. As a result, the convergence of deceleration propagation can be improved, and as a result, traffic congestion can be further alleviated.

  Furthermore, the vehicle 2C, which is farther from the congestion factor occurrence point P than the vehicle 2B, has a smaller deceleration amount W than the vehicle 2B, and the vehicle 2D, which is farther from the congestion factor occurrence point P than the vehicle 2C, By setting the deceleration amount W to be smaller than that of 2C, it becomes possible to reduce the propagation of the influence of deceleration on the rear vehicle, and it is possible to surely reduce traffic congestion.

(Second Embodiment)
The traffic jam mitigation system according to the second embodiment is configured in substantially the same manner as the traffic jam mitigation system 1 according to the first embodiment, and the roadside communication device 3 is not provided as compared with the traffic jam mitigation system 1. Is different. In the second embodiment, the description of the same parts as those in the first embodiment will be omitted, and the differences will be mainly described.

  The configuration of the vehicle of the traffic jam mitigation system according to the present embodiment is substantially the same as that of the vehicle 2R of the traffic jam mitigation system 1 according to the first embodiment. This is different. For example, a millimeter wave sensor and an image sensor for detecting the behavior of the preceding vehicle and the oncoming vehicle are provided. Further, the ECU 20 has a function of predicting a congestion factor occurrence point P based on information detected by the sensor and calculating a deceleration amount by which the host vehicle decelerates to the predicted congestion factor occurrence point P. The calculation method is the same as that of the acceleration / deceleration amount calculation unit 32 of the roadside communication device 3 of the first embodiment. And the communication control part 21 has a function which notifies the positional information on the congestion factor generation | occurrence | production location P to a subsequent vehicle by vehicle-to-vehicle communication.

  Next, the operation of the traffic jam alleviation system according to the second embodiment will be described. FIG. 7 is an example of a traffic state at a point where traffic congestion is likely to occur, and is a schematic diagram for explaining the operation of the traffic congestion mitigation system.

As shown in FIG. 7, in one side lane, vehicles 2A to 2E are heading toward intersection K, and in the opposite lane, there is a vehicle 4A that is going to turn right at intersection K. Further, it is assumed that the vehicles 2A to 2E share the inter-vehicle distance information obtained from information such as sensors. In such a case, when the vehicle 2A first recognizes the presence of the vehicle 4A based on information such as a sensor, the vehicle 2A transmits right turn vehicle recognition information to the subsequent vehicle 2B. When the vehicle 2B recognizes the presence of the vehicle 4A based on the information obtained from the vehicle 2A, the vehicle 2A exits the region U between the vehicle 2A and the vehicle 2B based on the distance between the vehicles 2A. Determine if will turn right. This determination is executed by the ECU 20. When the ECU 20 determines that the vehicle 4A turns right, the position information of the intersection K is transmitted to the vehicle 2C of the subsequent vehicle. Similarly, the vehicle 2C transmits information to the vehicle 2D, and the vehicle 2D similarly transmits information to the vehicle 2E. Thereby, each vehicle 2B-2E recognizes the distance to the intersection K at substantially the same time t. And each vehicle 2B-2E calculates the distance to the point (target point) which must decelerate in order for the vehicle 4A to turn right safely in consideration of the number of vehicles ahead. Each vehicle has a deceleration amount W _2B , W _2C , W _2D , W _{2E of} the own vehicle based on the distance to the target point and the predicted time for the preceding vehicle to reach the target point. Generate a speed pattern.

  As a result, the longer the vehicle is from the intersection K, the longer the time required for deceleration control can be set. Therefore, for example, as shown in FIGS. Generated. Therefore, a vehicle with a farther distance from the intersection K has a speed pattern with a gradual speed change, so that the propagation of deceleration can be reduced, and as a result, traffic congestion can be reduced.

  As described above, according to the traffic jam mitigation system of the second embodiment, the deceleration amount of each vehicle can be controlled without providing the roadside communication device 3, and the deceleration amount can be reduced to become a gradual speed change as the vehicle becomes a subsequent vehicle. Therefore, the convergence of deceleration propagation can be improved. As a result, traffic congestion can be reduced.

  Each embodiment mentioned above shows an example of a traffic jam alleviation system concerning the present invention. The traffic jam mitigation system according to the present invention is not limited to the traffic jam mitigation system according to these embodiments. Or it may be applied to other things.

  For example, in the first embodiment, a case will be described in which all of the subsequent vehicles following the leading vehicle perform deceleration control based on the deceleration amount generated by the roadside communication device 3, and in the second embodiment, a congestion factor is generated. Although the case where all the following vehicles following the leading vehicle perform the deceleration control based on the point has been described, it is not necessary for all the following vehicles to perform such a deceleration control, for example, the congestion factor generation point P from the vehicle 2B. If the vehicle 2D far from the vehicle satisfies the relationship that the deceleration amount of the vehicle 2D is smaller than the deceleration amount of the vehicle 2B, even if the vehicle 2C that is the vehicle ahead of the vehicle 2D performs the deceleration control in the normal travel, the vehicle 2B and Since the vehicle 2D starts the deceleration control in advance, the propagation of the deceleration is suppressed with respect to the subsequent vehicles after the vehicle 2D. As a result, traffic congestion can be reduced.

  Further, in the first embodiment, a case will be described in which the following vehicle first recognizes the occurrence of the congestion factor among the vehicles to be subjected to deceleration control, and in the second embodiment, the leading vehicle first generates the congestion factor. In each embodiment, the order of recognizing the occurrence of a congestion factor is not limited, and the convergence of deceleration propagation can be improved in any order. As a result, traffic congestion can be reduced.

  Further, in the first embodiment, the case where the vehicle speed is 90 km / h and the inter-vehicle distance is not more than 30 m is the final cruising state, but it may be a case where one of the conditions is targeted, In each vehicle, the maximum deceleration does not exceed the threshold, the maximum acceleration does not exceed the threshold, the maximum inter-vehicle distance does not exceed the threshold or less, the vehicle speed does not exceed the threshold or less, etc. You may combine conditions. In this case, the threshold value may be fixed or variable. Then, by setting the deceleration lower limit value in a range in which the brake lamp is not lit, it is possible to prevent the propagation of deceleration induced by visual observation. When this brake lamp is used as a threshold value, more accurate control is possible by determining the distance according to the distance from the leading vehicle to the vehicle to be controlled, the inter-vehicle distance, and the like. And the conditions mentioned above do not need to be unified in the whole vehicle to be controlled, and may be set separately for each vehicle.

  In the first and second embodiments, the case of one lane on one side has been described, but two or more lanes may be used. In the case of two or more lanes, more accurate control is possible by taking into account the behavior of a vehicle traveling in the adjacent lane and changing the inter-vehicle distance according to the interruption of another vehicle, for example.

  In the first and second embodiments, an example has been described in which a space is secured by decelerating when the vehicle 4A joins or when the vehicle 4A turns right. However, a space or right turn that joins by acceleration control is described. You may secure the space to do.

  In the first and second embodiments, the traffic jam that occurs when the vehicle 4A joins or the vehicle 4A turns to the right has been described, but the traffic jam occurrence point is not limited to this.

  In the first and second embodiments, the case where the vehicle 2R has an automatic driving function has been described. However, manual driving may be used. For example, by displaying the deceleration amount on the display unit 24 provided in the vehicle 2R, or displaying the brake depression amount, etc., deceleration control can be performed even in manual operation.

  Furthermore, in the first and second embodiments, an example has been described in which a speed pattern is created once and travel control is performed in accordance with the created speed pattern. However, the speed pattern may be created dynamically and initially generated. When the speed pattern is different from the speed pattern, control may be performed according to the speed pattern immediately after generation. In this case, it is preferable that the speed pattern changes smoothly.

It is a block diagram which shows the structure outline | summary of a vehicle provided with the traffic congestion mitigation system which concerns on 1st Embodiment. It is a sequence diagram which shows operation | movement of the traffic congestion alleviation system of FIG. It is a flowchart which shows operation | movement of the roadside communication apparatus of FIG. It is a flowchart which shows operation | movement of the vehicle of FIG. It is a schematic diagram for demonstrating operation | movement of the traffic congestion alleviation system of FIG. It is a schematic diagram for demonstrating the effect of the traffic congestion alleviation system of FIG. It is a schematic diagram for demonstrating operation | movement of the traffic congestion relaxation system which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Congestion alleviation system, 2R, 2N, 2M, 4A ... Vehicle, 3 ... Roadside communication apparatus, 20 ... ECU, 21 ... Communication control part, 22 ... Acceleration / deceleration control part, 30 ... Communication control part, 31 ... Congestion judgment part 32 Acceleration / deceleration amount calculation unit.

Claims (3)

A traffic jam mitigation system that mitigates vehicle traffic,
A traffic jam judging means for judging whether there is a traffic jam factor,
When it is determined that the congestion factor is present in the congestion determination unit, the vehicle includes a deceleration unit that performs deceleration control in advance for a plurality of subsequent vehicles viewed from any vehicle heading to the congestion factor occurrence point,
The deceleration means controls the second succeeding vehicle, which is far from the first succeeding vehicle, from the congestion factor occurrence point to decelerate with a deceleration amount smaller than the deceleration amount of the first succeeding vehicle. This is a traffic jam alleviation system.   The congestion reducing system according to claim 1, wherein the deceleration unit performs deceleration control with a smaller deceleration amount as a subsequent vehicle that is farther from the congestion factor occurrence point. 3. The traffic jam according to claim 1, wherein the deceleration unit controls the second succeeding vehicle to perform deceleration control with the deceleration amount so as to reach a target speed to be achieved before reaching the traffic jam factor occurrence point. Mitigation system.

Images