JP2018106354A - Vehicle spee control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly make a vehicle merge while suppressing acceleration/deceleration of the vehicle that is being traveled on a main track road.SOLUTION: A vehicle speed control device (11) comprises adjustment means (111 and 112) by which, while a vehicle (10) is traveled on a merging road merging into a main track road, (i) the time for the other vehicle being traveled at a first point before a merging point on the main track road to reach the merging point is estimated by acquiring a speed of the other vehicle and (ii) a speed of the vehicle is adjusted from a second point before the merging point on the merging road to the merging point in such a manner that the vehicle reaches the merging point while avoiding a predetermined time zone including the estimated time.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle speed control device, and more particularly, to a technical field of a vehicle speed control device that controls the speed of the host vehicle when the host vehicle joins a main road ahead of the traveling direction.

  As this type of device, for example, when a merging point is present in front of the road on which the host vehicle is traveling, other vehicles traveling on the merging partner side road (that is, the main road) within a predetermined range from the merging point An apparatus has been proposed that adjusts the speed of the host vehicle so that smooth merging is possible based on information on the arrival time until the merging point is reached (see Patent Document 1).

JP-A-11-161895

  According to the technique described in Patent Document 1, changes in speed of other vehicles traveling on the main road are not taken into consideration. However, in reality, when the driver of another vehicle traveling on the main road recognizes the vehicle that is joining, there is a possibility that the other vehicle will accelerate or decelerate. Then, with the technique described in Patent Document 1, the host vehicle may not be able to smoothly join the main road.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a vehicle speed control device capable of smoothly joining the host vehicle while suppressing acceleration / deceleration of the vehicle traveling on the main road. And

  In order to solve the above problems, the vehicle speed control device according to the present invention is configured such that (i) the main road and the merging road in the main road when the host vehicle is traveling on the merging road joining the main road. The speed of the other vehicle that travels at the first point before the merging point with the vehicle is acquired, the time when the other vehicle reaches the merging point is predicted, and (ii) the host vehicle is the predicted time The vehicle is provided with adjusting means for adjusting the speed of the host vehicle from the second point before the joining point to the joining point on the joining road so as to reach the joining point while avoiding a predetermined time range including .

  If the driver of a vehicle traveling on the main road recognizes that the vehicle traveling on the merging road will reach the merging point clearly earlier or later than the driver, the driver may accelerate or decelerate the vehicle. Is considered relatively low. On the other hand, if the driver of the vehicle traveling on the main road recognizes that the vehicle traveling on the junction road reaches the junction at the same time as the driver, the driver may accelerate or decelerate the vehicle. Is considered relatively high.

  The vehicle speed control device avoids a predetermined time range including the time at which other vehicles traveling on the main road reach the junction, so that the own vehicle traveling on the junction road reaches the junction (in other words, The speed of the host vehicle is adjusted so that the vehicle does not reach the meeting point at the same time as other vehicles. For this reason, according to the vehicle speed control device, it is possible to smoothly join the host vehicle to the main road while suppressing acceleration / deceleration of the vehicle traveling on the main road.

  The effect | action and other gain of this invention are clarified from the form for implementing demonstrated below.

It is a block diagram which shows the structure of the vehicle which concerns on embodiment. It is a conceptual diagram which shows the concept of the vehicle speed control which concerns on embodiment. It is a graph which shows an example of vehicle speed control in the case of joining between the i-th vehicle and the (i + 1) th vehicle which drive | work a main road. It is a figure which shows an example of the condition where the vehicle speed control which concerns on embodiment is implemented. It is a flowchart which shows the process which calculates the arrival time to the junction of the vehicle which drive | works the main road which concerns on embodiment. It is a flowchart which shows vehicle speed control which concerns on embodiment.

  An embodiment according to a vehicle speed control device of the present invention will be described with reference to FIGS. 1 to 6. The vehicle speed control device according to the embodiment adjusts the speed of the vehicle so that a vehicle traveling on a merge road (for example, a rampway) that merges with the main road on an expressway, an automobile exclusive road, or the like can smoothly merge with the main road. Control.

(Vehicle configuration)
A configuration of a vehicle on which the vehicle speed control device according to the embodiment is mounted will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of a vehicle according to the embodiment.

  In FIG. 1, a vehicle 10 includes an ECU (Electronic Control Unit) 11, a positioning device 12, a communication device 13, a map database 14, and an actuator 15.

  The ECU 11 performs overall control of various devices of the vehicle 10. In this embodiment, a part of the function of the ECU 11 is used as a vehicle speed control device. The ECU 11 as a vehicle speed control device includes a prediction unit 111 and a vehicle speed adjustment unit as a processing block logically realized therein or as a processing circuit physically realized in order to control the speed of the vehicle 10. 112.

  The positioning device 12 can receive satellite signals such as navigation signals from navigation satellites, for example, and has an internal sensor such as a gyro sensor. The positioning device 12 detects the position of the vehicle 10 based on at least one of the satellite signal and the output of the internal sensor. That is, the positioning device 12 is configured to be able to detect the position of the vehicle 10 by, for example, GNSS (Global Navigation Satellite System) or DR (Dead Recking).

  The communication device 13 is configured to be able to transmit and receive data by wireless communication such as road-to-vehicle communication and vehicle-to-vehicle communication. The map database 14 is a database that stores map information. The map information includes, for example, road position information, information such as road shape, width, and gradient, position information of intersections, branch points, and merge points. The actuator 15 is configured to be able to adjust the opening of a throttle valve or the like of an engine (not shown), for example.

(Vehicle speed control)
Outline of Vehicle Speed Control In the vehicle 10 configured as described above, an outline of vehicle speed control performed by the ECU 11 as a vehicle speed control device will be described with reference to FIG. FIG. 2 is a conceptual diagram illustrating the concept of vehicle speed control according to the embodiment.

  First, as a premise, a vehicle speed detector 30 for detecting the speed of a vehicle (vehicle 21 in FIG. 2) traveling on the main road is installed at a detection point just a distance L1 from the junction on the main road. The vehicle speed detector 30 transmits the detected vehicle speed and detection time to a vehicle (particularly, a vehicle traveling on a junction road) existing within a predetermined range from the vehicle speed detector 30 by wireless communication.

  The ECU 11 of the vehicle 10 traveling on the junction road receives the vehicle speed and the detection time detected by the vehicle speed detector 30 via the communication device 13 at the reception point on the junction road. The prediction unit 111 of the ECU 11 predicts the time when the vehicle traveling on the main road reaches the junction based on the received vehicle speed and detection time.

  In the vicinity of the merging point, there is a possibility that the speed of the vehicle traveling on the main road cannot be acquired by inter-vehicle communication due to, for example, a relatively complicated road shape. If it is set as the structure which acquires the speed of the vehicle which drive | works a main road from the vehicle speed detector 30 like this embodiment, the speed of the vehicle which drive | works a main road can be acquired reliably.

  The vehicle speed adjustment unit 112 adjusts the speed of the vehicle 10 via the actuator 15 based on the time predicted by the prediction unit 111. At this time, the vehicle speed adjustment unit 112 adjusts the speed of the vehicle 10 so that the speed of the vehicle 10 reaches the main line average vehicle speed V before reaching the junction.

  Here, in particular, the vehicle speed adjusting unit 112 is a section from the reception point to the junction point on the junction road, as shown in FIG. 2, a section in which the vehicle 10 cannot be seen by the driver of the vehicle traveling on the main road by the shielding ( That is, the speed of the vehicle 10 is adjusted (controlled) by dividing it into a control section (1)) and a section where the vehicle 10 can be seen by the driver of the vehicle traveling on the main road (that is, the control section (2)). The “shielding object” is not limited to a building such as a soundproof wall, for example, and the driver of the vehicle traveling on the main road recognizes the vehicle traveling on the confluence road, such as a difference in height between the main road and the confluence road. It is a concept that includes structures that cannot.

  The speed of the vehicle 10 at the reception point is Vs, and the speed of the vehicle 10 at the visible starting point (a point where the vehicle 10 starts to be visible from the driver of the vehicle traveling on the main road) is V0 (where V> V0> Vs). . In the control section (1), the vehicle speed adjustment unit 112 accelerates the vehicle 10 at a constant acceleration via the actuator 15 so that the speed of the vehicle 10 reaches the vehicle speed V0 when reaching the visible start point. In the control section (2), the vehicle speed adjustment unit 112 appropriately accelerates the vehicle 10 via the actuator 15 until the speed of the vehicle 10 reaches the main line average vehicle speed V. Particularly in the control section (2), the vehicle 10 joins the main road at the same time as the vehicle arrives at the joining point (that is, the vehicle 10 joins the driver). The vehicle adjustment unit 112 adjusts the speed of the vehicle 10 so as not to think that the vehicle will reach the point.

  At this time, the vehicle speed adjustment unit 112 travels on the main road, for example, avoids a predetermined time range including the time when the vehicle 21 is expected to reach the joining point, and controls the control section so that the vehicle 10 reaches the joining point. The acceleration and acceleration time in (1) and (2) are adjusted. This point will be described with reference to FIG. FIG. 3 is a graph illustrating an example of vehicle speed control related to the vehicle 10 when the vehicle 10 merges between the i-th vehicle traveling on the main road and the (i + 1) -th vehicle. In FIG. 3, “Tb” and “Tf” are “rear safety inter-vehicle time” and “front safety inter-vehicle time”, respectively. Each of the rear safety inter-vehicle time Tb and the front safety inter-vehicle time Tf is determined according to the main line average vehicle speed V.

  In the example shown in FIG. 3, since the vehicle 10 joins between the i-th vehicle and the (i + 1) -th vehicle, the rear safety inter-vehicle time from the time Ti at which the i-th vehicle is expected to reach the joining point. The vehicle speed is adjusted so that the vehicle 10 arrives at the joining point from the time Ti + 1 expected to reach the joining point from the time later by Tb to the time earlier by the forward safety inter-vehicle time Tf from the time Ti + 1 expected to reach the joining point. The speed of the vehicle 10 is adjusted by the unit 112.

  If the acceleration of the vehicle 10 in the control section (2) is relatively large, the driver of the vehicle traveling on the main road may erroneously predict the timing at which the vehicle 10 joins the main road. For this reason, it is desirable that the acceleration of the vehicle 10 in the control section (2) is relatively small.

  In order to make the acceleration of the vehicle 10 relatively small in the control section (2), it is necessary to make the difference between the main line average vehicle speed V and the speed V0 of the vehicle 10 at the visible starting point relatively small. Therefore, the vehicle adjustment unit 112 adjusts the speed of the vehicle 10 also in the control section (1) so that the speed V0 of the vehicle 10 at the visible starting point becomes a desirable speed.

  If attention is paid to the i-th vehicle, the time from the time Ti when the i-th vehicle is expected to reach the joining point to the time after the time Tf earlier from the time Ti until the time Tb later than the time Ti from the time Ti The speed of the vehicle 10 is adjusted so that the vehicle 10 arrives at the joining point while avoiding (ie, Ti−Tf to Ti + Tb). The time range “Ti−Tf to Ti + Tb” corresponds to the predetermined time range described above.

Details of Vehicle Speed Control Next, details of the vehicle speed control according to the present embodiment will be described with reference to FIGS. Here, as shown in FIG. 4, it is assumed that vehicles 21, 22 and 23 are traveling on the main road.

  In FIG. 5, the prediction unit 111 of the ECU 11 serving as the vehicle speed control device receives the vehicle speed of the vehicle that has not passed through the merging point among the vehicle speeds detected by the vehicle speed detector 30 received via the communication device 13. In the example shown in FIG. 4, the vehicle speeds of the vehicles 21, 22 and 23 are extracted (step S101). In addition, the process of step S101 may be started on the condition that the signal transmitted from the vehicle speed detector 30 is received by the communication device 13.

  Next, the prediction unit 111 sets the average value of the extracted vehicle speeds as the main line average vehicle speed V (step S102). When only the vehicle speed of one vehicle is extracted in the process of step S101, the prediction unit 111 sets the extracted vehicle speed as the main line average vehicle speed V.

  Next, the prediction unit 111 refers to map information stored in the map database 14, for example, and acquires a distance L1 (see FIG. 2) from the detection point on the main road to the merge point. In addition, the positional information (namely, positional information which shows a detection point) which concerns on the vehicle speed detector 30 may be acquired from the vehicle speed detector 30 by radio | wireless communication, and may be contained in map information.

  The prediction unit 111 assumes that vehicles traveling on the main road (vehicles 21, 22 and 23 in the example shown in FIG. 4) travel from the detection point to the junction at the main line average vehicle speed V. Estimated arrival time at the meeting point is calculated (step S103). Here, it is assumed that the estimated arrival times of the vehicles 21, 22 and 23 are “T1”, “T2” and “T3”.

  In FIG. 6, after the process of step S103, the vehicle speed adjustment unit 112 of the ECU 11 sets an initial value “1” to the variable i (that is, initializes the variable i) (step S201). Note that the maximum value of the variable i (“n” in FIG. 6) is equal to the number of vehicles whose vehicle speed has been extracted in the process of step S101.

  Next, the vehicle speed adjustment unit 112 searches for a control plan that satisfies a condition when the vehicle 10 merges between the i-th vehicle Ni and the (i + 1) -th vehicle Ni + 1 (step S202). The conditions include three conditions: (i) Vs <V0 <V, (ii) Ti + Tb <Tmin, and (iii) Ti + 1−Tf> Tmax.

  In the present embodiment, the condition (i) is set on the assumption that the vehicle 10 does not decelerate from the reception point to the merge point on the merge road. Condition (ii) is that when the vehicle 10 merges between the vehicle Ni and the vehicle Ni + 1, the minimum time Tmin of the time when the vehicle 10 reaches the merge point is the rear safety inter-vehicle time Tb from the expected arrival time Ti of the vehicle Ni. It shows that it is larger than the later time only. Condition (iii) is that, when the vehicle 10 joins between the vehicle Ni and the vehicle Ni + 1, the maximum time Tmax of the time when the vehicle 10 reaches the joining point is the front safety inter-vehicle time Tf from the expected arrival time Ti + 1 of the vehicle Ni + 1. It is only smaller than the earlier time. That is, the conditions (ii) and (iii) limit that the vehicle 10 reaches the junction between time Ti + Tb and time Ti + 1−Tf in FIG.

  The vehicle speed adjustment unit 112 searches for a control plan as follows. The vehicle 10 travels while maintaining the acceleration As from the reception point on the joining road to the visible starting point, and travels while maintaining the acceleration A0 from the visible starting point to the joining point, and the speed of the vehicle 10 is the main vehicle average vehicle speed at the joining point. Let V be. Further, it is assumed that the distance from the reception point on the junction road to the visible origin is “L2”, and the distance from the visible origin to the junction is “L3”. The distances L2 and L3 may be acquired from map information stored in the map database 14, for example.

  The vehicle speed adjusting unit 112 determines the speed V0 of the vehicle 10 at the visible starting point so as to satisfy the condition (i). When the speed V0 is determined, the time T0 and the accelerations As and A0 required for the vehicle 10 to move from the reception point to the visible start point are uniquely determined. Here, the time T0 is “T0 = 2 × L2 / (Vs + V0)”, the acceleration As is “As = {(V0−Vs) (V0 + Vs)} / (2 × L2)”, and the acceleration A0 is “A0 = {(V−V0) (V + V0)} / (2 × L3)”.

  The vehicle speed adjustment unit 112 sets Tmax as the time when the vehicle 10 reaches the joining point when the vehicle 10 maintains the speed V0 from the visible starting point to the joining point. In this case, the time Tmax can be expressed as “Tmax = T0 + L3 / V0”. Further, the vehicle speed adjustment unit 112 sets Tmin as the time when the vehicle 10 reaches the joining point when the vehicle 10 travels from the visible starting point to the joining point while maintaining the acceleration A0. In this case, the time Tmin can be expressed as “Tmin = T0 + 2 × L3 / (V0 + V)”. The vehicle speed adjustment unit 112 determines that there is a control plan when the time Tmin and the time Tmax satisfy the above conditions (ii) and (iii), respectively. The vehicle speed adjustment unit 112 may search for a plurality of control plans while changing the speed V0.

  Next, the vehicle speed adjustment unit 112 determines whether or not there is a control plan as a result of the process of step S202 (step S203). In this determination, when it is determined that there is a control plan (step S203: Yes), the vehicle speed adjustment unit 112 performs the process of step S204. Here, the larger value of the acceleration As and the acceleration A0 (that is, “max (As, A0)”) is set as the maximum acceleration. In the process of step S204, the vehicle speed adjusting unit 112 sets a control plan having the minimum maximum acceleration between the vehicle Ni and the vehicle Ni + 1 on condition that there are a plurality of control plans searched by the process of step S202. A control plan when the vehicles 10 join is assumed to be “Ai” as the minimum value of the maximum acceleration.

  On the other hand, if it is determined in step S203 that there is no control plan (step S203: No), the vehicle speed adjustment unit 112 does not have a control plan that allows the vehicle 10 to merge between the vehicle Ni and the vehicle Ni + 1. That is, it is determined that the vehicle 10 cannot be merged between the vehicle Ni and the vehicle Ni + 1 (step S205).

  Next, the vehicle speed adjustment unit 112 determines whether or not the variable i is n−1 (step S206). In this determination, when it is determined that the variable i is not n−1 (step S206: No), the vehicle speed adjustment unit 112 increments the variable i (step S207) and performs the process of step S202. That is, for example, the vehicle speed adjustment unit 112 searches for a control plan for merging the vehicle 10 between the vehicle 21 and the vehicle 22 in FIG. 4, and then merges the vehicle 10 between the vehicle 22 and the vehicle 23. Search for.

  If it is determined in step S206 that the variable i is n−1 (step S206: Yes), the vehicle speed adjustment unit 112 has executed at least the control plan as a result of the processes in steps S202 to S207 being repeated. It is determined whether one exists (step S208).

  When it is determined in step S208 that at least one control plan exists (step S208: Yes), the vehicle speed adjustment unit 112 selects the control plan having the smallest “Ai” from among the existing control plans. Adopted as a control plan, the speed of the vehicle 10 is adjusted via the actuator 15 based on the adopted control plan (step S209).

  On the other hand, when it is determined in step S208 that there is no control plan (step S208: No), the vehicle speed adjustment unit 112 stops the merging of the vehicle 10 to the main road by the vehicle speed control (step S210). . At this time, the ECU 11 as the vehicle speed control device requests the driver of the vehicle 10 to manually join the main road to the main road via, for example, an HMI (Human Machine Interface) (not shown). To inform.

  The “predicting unit 111” and the “vehicle speed adjusting unit 112” according to the embodiment are examples of the “adjusting unit” according to the present invention. The “detection point (see FIG. 2)” and “reception point (see FIG. 2)” according to the embodiment are examples of the “first point” and the “second point” according to the present invention.

(Technical effect)
In the vehicle speed control according to the embodiment, a control plan that satisfies the above conditions (i), (ii), and (iii) is searched. If there is even one control plan, the vehicle 10 can be joined to the main road while avoiding a predetermined time range including the time when the vehicle traveling on the main road is expected to reach the joining point. For this reason, according to the vehicle speed control, the vehicle 10 can smoothly join the main road while suppressing acceleration / deceleration of the vehicle traveling on the main road.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and vehicle speed control with such a change is possible. The apparatus is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 10, 21, 22, 23 ... Vehicle, 11 ... ECU, 12 ... Positioning device, 13 ... Communication device, 14 ... Map database, 15 ... Actuator, 111 ... Prediction unit, 112 ... Vehicle speed adjustment unit

Claims (1)

  (I) The speed of another vehicle that travels at a first point before the junction between the main road and the junction road on the main road when the host vehicle is traveling on a junction road joining the main road. And (ii) the host vehicle avoids a predetermined time range including the predicted time and arrives at the merge point. A vehicle speed control device comprising adjusting means for adjusting the speed of the host vehicle from the second point before the junction point to the junction point on the junction road.

Images