Queue running system

Abstract

To provide a vehicle platoon system capable of improving fuel consumption efficiency / electricity consumption efficiency of a self vehicle more than that in a case where a solo travel of the self vehicle is continued in adaptive cruise control.SOLUTION: The present invention relates to a vehicle platoon system comprising a control device for controlling a travel of the self vehicle in adaptive cruise control. In a case where a preceding vehicle of a higher wind shield effect is detected ahead of the self vehicle by a detection device provided in the self vehicle during a solo travel of the self vehicle in the adaptive cruise control and a vehicle velocity of the preceding vehicle is higher than an ACC preset vehicle velocity of the self vehicle, the control device suggests that an attendant of the self vehicle increase the ACC preset vehicle velocity for a predetermined increase range using a proposing device provided in the self vehicle.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a platoon driving system.

Background Art

[0002] Patent Document 1 discloses a platoon driving system in which a preceding vehicle and a host vehicle can form an appropriate platoon order in platoon driving.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] If the host vehicle continues to drive alone with adaptive cruise control, it will lead to deterioration of fuel consumption and electricity consumption due to air resistance caused by wind during driving.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a platoon driving system that can improve the fuel consumption and electricity consumption of the host vehicle as compared with the case where the host vehicle continues to drive alone with adaptive cruise control.

Means for Solving the Problems

[0006] In order to solve the above-described problems and achieve the object, a platoon driving system according to the present invention is a platoon driving system including a control device that controls the driving of the host vehicle by an adaptive cruise control that adjusts the vehicle speed of the host vehicle so as to follow a preceding vehicle at a constant interval, wherein the control device, when the host vehicle is traveling alone by the adaptive cruise control, a preceding vehicle with a high windbreak effect is detected in front of the host vehicle by a detection device provided in the host vehicle, and when the vehicle speed of the preceding vehicle is higher than an ACC set vehicle speed set as the vehicle speed of the host vehicle in the adaptive cruise control of the host vehicle, a proposal to increase the ACC set vehicle speed by a predetermined increase width is made to a passenger of the host vehicle using a proposal device provided in the host vehicle.

[0007] As a result, it is possible to shift to platoon driving with a preceding vehicle having a high windbreak effect and improve the fuel consumption and power consumption of the host vehicle, rather than continuing the solo driving of the host vehicle by the adaptive cruise control.

[0008] Further, a platoon driving system according to the present invention is a platoon driving system including a control device that controls the driving of the host vehicle by an adaptive cruise control that adjusts the vehicle speed of the host vehicle so as to follow a preceding vehicle at a constant interval, wherein the control device, when the host vehicle is traveling alone by the adaptive cruise control, a preceding vehicle with a high windbreak effect is detected in front of the host vehicle by a detection device provided in the host vehicle, and when the vehicle speed of the preceding vehicle is higher than an ACC set vehicle speed set as the vehicle speed of the host vehicle in the adaptive cruise control of the host vehicle, executes control to automatically increase the ACC set vehicle speed by a predetermined increase width.

[0009] As a result, it is possible to shift to platoon driving with a preceding vehicle having a high windbreak effect and improve the fuel consumption and power consumption of the host vehicle, rather than continuing the solo driving of the host vehicle by the adaptive cruise control.

[0010] Also, in the above, when the relative speed between the host vehicle and the preceding vehicle is such that the host vehicle approaches the preceding vehicle, the ACC set vehicle speed may not be changed.

[0011] Thereby, while suppressing the host vehicle from rapidly approaching the preceding vehicle, it is possible to shift to platoon running.

[0012] Also, in the above, the predetermined increase width may be +1 to 2 [km / h] with respect to the vehicle speed of the preceding vehicle.

[0013] Thereby, while suppressing the host vehicle from rapidly approaching the preceding vehicle, it is possible to shift to platoon running.

[0014] Also, in the above, when the vehicle speed of the preceding vehicle is faster than a predetermined speed with respect to the ACC set vehicle speed of the host vehicle, the ACC set vehicle speed may not be changed.

[0015] Thereby, it is possible to suppress the deterioration of fuel consumption and power consumption due to excessive increase of the ACC set vehicle speed of the host vehicle.

[0016] Also, in the above, when the vehicle speed of the preceding vehicle exceeds the speed limit of either the preceding vehicle or the host vehicle in the driving lane, the ACC set vehicle speed may not be changed.

[0017] Thereby, it is possible to suppress the shift to platoon running in which the speed limit of either the preceding vehicle or the host vehicle is exceeded.

[0018] Also, in the above, the control device may obtain the projected area of the preceding vehicle based on an image obtained by photographing the preceding vehicle from behind by a photographing device provided on the host vehicle, and determine that the wind shielding effect of the preceding vehicle is high when the projected area is equal to or greater than a predetermined value.

[0019] Thereby, it is possible to determine whether or not the windbreak effect of the preceding vehicle is high.

Effect of the Invention

[0020] The platooning system according to the present invention has an effect that, when the platooning with a preceding vehicle having a higher windbreak effect is shifted to rather than the case where the autonomous driving of the host vehicle continues with adaptive cruise control, the fuel consumption and power consumption of the host vehicle can be improved.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0022] Embodiments of the platoon driving system according to the present invention will be described below. Note that the present invention is not limited by these embodiments. A vehicle equipped with a platoon driving system that can be targeted by the present invention is a vehicle that can travel following a preceding vehicle without the driver's operation. Specifically, it is configured to be able to control the driving force and braking force to maintain an appropriate distance from the preceding vehicle without the driver performing an accelerator operation or a brake operation. As an example of the control that can perform such following driving, conventionally known cruise control, adaptive cruise control (ACC) that keeps the distance from the preceding vehicle constant and stops the host vehicle when the preceding vehicle stops, and communication cooperative adaptive cruise control (CACC) that uses vehicle-to-vehicle communication to set the distance between the host vehicle and the preceding vehicle relatively short and enables platoon driving between the host vehicle and the preceding vehicle (including front and rear vehicles). Note that these cruise control controls are executed, for example, by a switch operation by the driver or a passenger, or by signals from various sensors.

[0023] FIG. 1 is a diagram for explaining an example of a host vehicle 100 equipped with a platoon driving system according to an embodiment.

[0024] As shown in FIG. 1, the host vehicle 100 equipped with a platoon driving system according to an embodiment is an example of a four-wheel drive vehicle based on a so-called FR (front engine - rear drive) vehicle that arranges the engine 1 on the front side of the host vehicle 100 and transmits the power of the engine 1 to the rear wheels 2. Further, the engine 1 is arranged between the left and right front wheels 3 on the front wheel 3 side (substantially at the center in the vehicle body width direction) and is directed toward the rear wheel 2 side. Note that this host vehicle 100 may be a four-wheel drive vehicle based on a so-called FF (front engine - front drive) vehicle.

[0025] A transmission 4 is arranged on the output side of the engine 1, and an output shaft (not shown) of the engine 1 is connected to an input shaft 5 of the transmission 4. The engine 1 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine, and is configured to control the throttle opening and the fuel injection amount according to a required driving force such as the depression amount (accelerator opening) of an accelerator pedal (not shown) and output torque corresponding to the required driving force. In the case of a gasoline engine, the opening of the throttle valve, the supply amount or injection amount of fuel, the execution and stop of ignition, and the ignition timing are electrically controlled. In the case of a diesel engine, the injection amount of fuel, the injection timing of fuel, or the opening of the throttle valve in an EGR (Exhaust Gas Recirculation) system is electrically controlled.

[0026] As shown in FIG. 1, the transmission 4 is arranged on the same axis as the engine 1 and transmits torque between the engine 1, the first motor (MG1) 6, and the drive wheels. The transmission 4 is a mechanism capable of appropriately changing the ratio of the input rotation speed to the output rotation speed, and can be configured by a stepped transmission, a continuously variable transmission capable of continuously changing the transmission ratio, or the like. The transmission 4 more preferably includes a clutch mechanism 7 capable of transmitting torque by engagement and blocking torque transmission by disengagement to set a neutral state.

[0027] The clutch mechanism 7 selectively transmits and interrupts power between the engine 1 (and the first motor 6) and the drive wheels. In the example shown in FIG. 1, the clutch mechanism 7 is provided in the transmission 4 as described above. Specifically, the clutch mechanism 7 has a friction plate 8(8a) connected to a rotating member (not shown) on the engine 1 side, and a friction plate 8(8b) connected to a rotating member (not shown) on the rear wheel 2 side. Also in FIG. 1, although not shown, the clutch mechanism 7 may be configured by, for example, a multi-plate clutch having a plurality of friction plates on one side and a plurality of friction plates on the other side, and alternately arranging the plurality of friction plates on one side and the plurality of friction plates on the other side. Further, in the vehicle 100 according to the embodiment, the clutch mechanism 7 is not limited to the clutch mechanism incorporated inside the transmission 4 as shown in FIG. 1. For example, it may be a friction clutch provided as a starting clutch between the first motor 6 and the transmission 4. In any case, by releasing the clutch mechanism 7, the engine 1 and the first motor 6 are disconnected from the drive system of the vehicle 100. Also, by engaging the clutch mechanism 7, the engine 1 and the first motor 6 are connected to the drive system of the vehicle 100.

[0028] The engine 1 and the transmission 4 are arranged on the same axis as described above, and the first motor 6 is arranged between the engine 1 and the transmission 4. The first motor 6 has a function (generator function) as a generator that generates electricity by being driven by receiving the engine torque output by the engine 1, and also has a function (motor function) as an electric motor that is driven by being supplied with electric power and outputs motor torque. That is, the first motor 6 is a motor having a generator function (so-called motor - generator), and is configured by, for example, a permanent magnet synchronous motor, or an induction motor, etc. Note that the first motor 6 may be directly connected to the output shaft of the engine 1 or the input shaft 5 of the transmission 4, or may be connected to the output shaft of the engine 1 or the input shaft 5 of the transmission 4 via an appropriate transmission mechanism.

[0029] A transfer 9 for four-wheel drive is arranged on the output side of the transmission 4. The transfer 9 is a mechanism that distributes the power output by the engine 1 or the torque output from the transmission 4 to the rear wheel 2 side and the front wheel 3 side. A rear propeller shaft 10 is connected to a member (not shown) that outputs torque to the rear wheel 2 side, and a front propeller shaft 11 is connected to a member (not shown) that outputs torque to the front wheel 3 side.

[0030] The transfer 9 can be constituted by a wrapping transmission mechanism using a chain or a belt or a gear mechanism. Further, the transfer 9 can be constituted by a full-time four-wheel drive mechanism provided with a differential mechanism that enables differential rotation between the front wheel 3 and the rear wheel 2 and a differential limiting mechanism that limits the differential rotation by a friction clutch or the like, or a part-time four-wheel drive mechanism that selectively shuts off the transmission of torque to the front wheel 3 side.

[0031] The rear propeller shaft 10 extends rearward of the vehicle 100 from the transmission 4 or the transfer 9 and is connected to the rear differential gear 12. The rear differential gear 12 is a final reduction gear that transmits torque to the left and right rear wheels 2, and the rear wheels 2 are connected to the rear differential gear 12 via two drive shafts 13 extending in the vehicle width direction. Further, the rear wheels 2 are configured such that the steering angle changes by the steering device 14. That is, the left and right rear wheels 2 also function as steering wheels. Furthermore, the vehicle 100 shown in FIG. 1 is connected to a braking device (brake) 15 for applying a braking force to each of the rear wheels 2 and the front wheels 3. The front propeller shaft 11 extends forward of the vehicle 100 and is connected to the front differential gear 16. The front differential gear 16 is a final reduction gear that transmits torque to the left and right front wheels 3, and the front wheels 3 are connected to the front differential gear 16 via two drive shafts 17 extending in the vehicle width direction.

[0032] In addition, a second motor (MG2) 18 that drives the front propeller shaft 11 is connected to the transfer 9. The second motor 18 is mainly a motor that outputs driving torque for traveling. In order to perform energy regeneration during deceleration, the second motor 18 is preferably configured by a motor-generator having a power generation function, such as a permanent magnet synchronous motor, similar to the first motor 6 described above.

[0033] The first motor 6 and the second motor 18 are each electrically connected to a power storage device (BAT) 19, such as a storage battery or a capacitor, via an inverter (not shown). Therefore, it is possible to make the first motor 6 and the second motor 18 function as motors by the power of the power storage device 19, or to charge the power storage device 19 with the power generated by each of the motors 6 and 18. It is also possible to make the second motor 18 function as an electric motor by the power generated by the first motor 6 and travel with the torque of the second motor 18.

[0034] In addition, the host vehicle 100 according to the embodiment can travel in a plurality of driving modes by controlling the engine 1, the first motor 6, the second motor 18, and the clutch mechanism 7 respectively. That is, the host vehicle 100 can travel in an EV driving mode in which the motor torque output by the second motor 18 is transmitted to the drive wheels to generate a driving force with the engine 1 stopped, and in a state where the clutch mechanism 7 is disengaged, the engine 1 is operated, the first motor 6 is driven by the engine torque to generate electricity, and the motor torque of the second motor 18 is transmitted to the drive wheels to generate a driving force. In a series HV driving mode, and in a parallel HV driving mode in which the engine 1 is operated with the clutch mechanism 7 engaged, and the engine torque and the motor torque of the second motor 18 are transmitted to the drive wheels to generate a driving force. Then, the switching between such driving modes is set, for example, using a mode switching map or the like that uses the required driving force and vehicle speed as parameters. Note that the host vehicle 100 according to the embodiment can also switch between a four-wheel drive mode (4WD) and a two-wheel drive mode (2WD), and such a driving mode switch can be configured to be controlled, for example, by the operation of a mode switch by the driver or based on the friction coefficient of the road surface.

[0035] And the host vehicle 100 is provided with an ECU (electronic control unit) 20 that controls the engine 1, the transmission 4, the clutch mechanism 7, the transfer 9, and the motors 6 and 18. This ECU 20 is mainly composed of a microcomputer, and is configured to perform calculations using the input data, the data stored in advance, and the program, and output the calculation result as a control command signal.

[0036] FIG. 2 is a diagram showing an example of the system configuration of the ECU 20.

[0037] As shown in FIG. 2, the ECU 20 includes a main controller 21, a drive controller 22 that receives a signal output from the main controller 21 and converts the input signal, and a sub-controller 23. The drive controller 22 is configured to output signals to a throttle actuator provided in the engine 1, an inverter (not shown) provided in each of the motors 6, 18, and the like. The sub-controller 23 is configured to output signals to actuators provided in various devices such as the clutch mechanism 7.

[0038] The main controller 21 is mainly composed of a microcomputer, and receives signals from main internal sensors 24 that detect the running state of the host vehicle 100, the operating states and behaviors of each part, and the like. The internal sensors 24 include, for example, an accelerator sensor 26 that detects the depression amount of the accelerator pedal 25, a brake sensor (or brake switch) 28 that detects the depression amount of the brake pedal 27, a steering angle sensor 30 that detects the steering angle of the steering wheel 29, vehicle speed sensors 31 that respectively detect the rotational speeds of the rear wheels 2 and the front wheels 3, a longitudinal acceleration sensor 32 that detects the longitudinal acceleration of the host vehicle 100, a lateral acceleration sensor 33 that detects the lateral acceleration of the host vehicle 100, a yaw rate sensor 34 that detects the yaw rate of the host vehicle 100, and a shift sensor 36 that detects the position of the shift lever (or shift switch) 35. Based on the signals input from the internal sensors 24, arithmetic expressions or maps stored in advance, etc., signals for controlling the engine 1 and the motors 6, 18 are output to the drive controller 22, and signals for controlling the clutch mechanism 7 and the like are output to the sub-controller 23. In FIG. 1, as examples of the input or output signals, the signals input from the internal sensors 24 to the ECU 20 and the signals output from the ECU 20 to the engine 1, the motors 6, 18, and the braking device 15 are shown by broken lines.

[0039] Furthermore, the host vehicle 100 to be controlled in the embodiment is capable of autonomous driving that automatically controls the driving operation of the host vehicle 100 to make it run. The autonomous driving defined in the embodiment means that all driving operations such as recognition of the driving environment, monitoring of the surrounding situation, and starting / accelerating, steering, and braking / stopping are all performed by the control system of the host vehicle 100. For example, it is highly autonomous driving or fully autonomous driving corresponding to "Level 4" in the automation level formulated by NHTSA (National Highway Traffic Safety Administration of the United States) or "Level 4" and "Level 5" in the automation level formulated by SAE (Society of Automotive Engineers) of the United States. Therefore, the host vehicle 100 to be controlled in the embodiment can run by autonomous driving even in a situation where there are no passengers (drivers, passengers, and passengers, etc.) in the vehicle. That is, the host vehicle 100 can perform manned autonomous driving in which it runs by autonomous driving with passengers in the vehicle and unmanned autonomous driving in which it runs by autonomous driving with no passengers in the vehicle. Note that the host vehicle 100 may be configured to be able to select an autonomous driving mode in which it runs by autonomous driving and a manual driving mode in which the driver performs the driving operation of the host vehicle 100, as defined in "Level 4" in the above-mentioned SAE automation level, for example.

[0040] Therefore, the host vehicle 100 can perform so-called autonomous driving in which it runs by automatically controlling each of the motors 6 and 18, the braking device 15, or the steering device 14 without the passenger (person) performing the driving operation. Each of the motors 6 and 18, the steering device 14, and the braking device 15, etc. during such autonomous driving are also controlled by the ECU 20.

[0041] In the main controller 21, in addition to the internal sensor 24 for performing autonomous driving, signals are input from main external sensors 37 that detect the surrounding information and external conditions of the host vehicle 100. The external sensors 37 are, for example, in-vehicle cameras, radars (RADAR: Radio Detection and Ranging), lidars (LIDAR: Laser Imaging Detection and Ranging), vehicle-to-vehicle communication, and the like.

[0042] The in-vehicle camera is installed, for example, inside the windshield of the host vehicle 100 and is configured to transmit imaging information regarding the external conditions of the host vehicle 100 to the main controller 21. The in-vehicle camera may be a monocular camera or a stereo camera. The stereo camera has a plurality of imaging units arranged to reproduce binocular parallax. According to the imaging information of the stereo camera, information in the depth direction in front of the vehicle can also be obtained.

[0043] The radar is configured to detect other vehicles, obstacles, etc. outside the host vehicle 100 using radio waves such as millimeter waves and microwaves, and transmit the detection data to the main controller 21. For example, radio waves are radiated around the host vehicle 100, and other vehicles, obstacles, etc. are detected by receiving the radio waves reflected by hitting other vehicles, obstacles, etc. and performing measurement and analysis.

[0044] The lidar is configured to detect other vehicles, obstacles, etc. outside the host vehicle 100 using laser light, and transmit the detection data to the main controller 21. For example, laser light is radiated around the host vehicle 100, and other vehicles, obstacles, etc. are detected by receiving the laser light reflected by hitting other vehicles, obstacles, etc. and performing measurement and analysis.

[0045] Vehicle-to-vehicle communication is a system that obtains information about surrounding vehicles (such as destination, position, speed, direction of travel, and vehicle control information, etc.) through wireless communication between vehicles, and provides safe driving support to drivers and passengers as needed. In addition, this vehicle-to-vehicle communication can receive services through information exchange between vehicles equipped with in-vehicle units of the ITS (Intelligent Transport Systems) safe driving support wireless system, and services can be enjoyed in unspecified locations where infrastructure facilities are not well-developed. Therefore, services can be received even in places where it is difficult to install infrastructure facilities.

[0046] In addition to the internal sensor 24 and the external sensor 37 as described above, signals are input to the main controller 21 from a GPS (Global Positioning System) receiver 38, a map database 39, a navigation system 40, etc. The GPS receiver 38 is configured to measure the position of the host vehicle 100 (for example, the latitude and longitude of the host vehicle 100) by receiving radio waves from a plurality of GPS satellites, and transmit the position information to the main controller 21. The map database 39 is a database that stores map information, and for example, data stored in a computer of an external facility such as an information processing center that can communicate with the host vehicle 100 can be used. Note that the computer of the above-mentioned external facility includes the above-mentioned vehicle-to-vehicle communication, vehicle-road communication between the host vehicle 100 and communication devices and signposts installed outside the road or on the roadside, and so-called big data accumulated and updated at any time in a server (not shown) such as an external data center. In addition, the map database 39 may be stored inside the main controller 21. The navigation system 40 is configured to calculate the driving route of the host vehicle 100 based on the position information of the host vehicle 100 measured by the GPS receiver 38 and the map information of the map database 39.

[0047] The main controller 21 performs calculations using detection data, information data input from internal sensors 24, external sensors 37, etc., and data stored in advance, and based on the calculation results, outputs signals to the drive controller 22, the sub-controller 23, and the auxiliary equipment 41. Then, the drive controller 22 outputs a control command signal to the actuators of the engine 1 (including the throttle valve) and the motors 6, 18, and the sub-controller 23 is configured to output a control command signal to the actuators of each part of the host vehicle 100 such as the braking device 15 and the steering device 14. In the following description, the actuators may simply be referred to as actuator 42 without distinguishing each actuator.

[0048] As main actuators 42 for automatically driving the host vehicle 100, a brake actuator, a steering actuator, etc. are provided. The brake actuator is configured to operate the braking device 15 according to a control signal output from the sub-controller 23 and control the braking force applied to the rear wheels 2 and the front wheels 3. The steering actuator is configured to drive the assist motor of the electric power steering device according to a control signal output from the sub-controller 23 and control the steering torque.

[0049] The auxiliary equipment 41 is a device or apparatus not included in the actuator 42, and is, for example, a device or apparatus not directly involved in the driving operation of the host vehicle 100 such as a wiper, a headlight, a direction indicator, an air conditioner, and an audio device.

[0050] The main controller 21 has, as a main control unit for automatically driving the host vehicle 100, for example, a vehicle position recognition unit 43, an external situation recognition unit 44, a running state recognition unit 45, a running plan generation unit 46, a running control unit 47, an auxiliary equipment control unit 48, and an attended / unattended determination unit 49.

[0051] The vehicle position recognition unit 43 is configured to recognize the position of the host vehicle 100 on the map based on the position information of the host vehicle 100 received by the GPS reception unit 38 and the map information of the map database 39. Note that the position of the host vehicle 100 used in the navigation system 40 can also be acquired from the navigation system 40. Alternatively, when it is possible to measure the position of the host vehicle 100 with a sensor installed outside the road or beside the road, the position of the host vehicle 100 can also be acquired by communicating with the sensor.

[0052] The external situation recognition unit 44 is configured to recognize the external situation of the host vehicle 100 based on, for example, the imaging information of an in-vehicle camera or the detection data of a radar or lidar. As the external situation, for example, information such as the position of the driving lane, the road width, the shape of the road, the road surface gradient, and obstacles around the vehicle is acquired. Also, as the driving environment, the surroundings of the host vehicle 100, as well as the terrain / weather information, road shape, and friction coefficient of the road surface of the driving route may be acquired.

[0053] The driving state recognition unit 45 is configured to recognize the driving state of the host vehicle 100 based on various detection data of the internal sensor 24. As the driving state of the host vehicle 100, for example, vehicle speed, longitudinal acceleration, lateral acceleration, and yaw rate are acquired.

[0054] The driving plan generation unit 46 is configured to generate a driving route of the host vehicle 100 based on, for example, the target route calculated by the navigation system 40, the position of the host vehicle 100 recognized by the vehicle position recognition unit 43, and the external situation recognized by the external situation recognition unit 44. The driving route is a trajectory along which the host vehicle 100 travels along the target route. Also, the driving plan generation unit 46 generates a driving route so that the host vehicle 100 can travel appropriately along the criteria such as traveling safely, complying with laws and regulations, and traveling efficiently on the target route.

[0055] And the travel plan generation unit 46 is configured to generate a travel plan according to the generated route. Specifically, at least based on the external situation recognized by the external situation recognition unit 44 and the map information of the map database 39, a travel plan along a preset target route is generated.

[0056] The travel plan presets the travel state of the host vehicle 100 including the future driving force requirement of the host vehicle 100, and is generated based on, for example, data several seconds ahead from the current time. Depending on the external situation and travel situation of the host vehicle 100, data dozens of seconds ahead from the current time can also be used. The travel plan is output from the travel plan generation unit 46 as data indicating the transitions of, for example, vehicle speed, acceleration, and steering torque when the host vehicle 100 travels along the target route.

[0057] Also, the travel plan can be output from the travel plan generation unit 46 as a speed pattern, an acceleration pattern, and a steering pattern of the host vehicle 100. The speed pattern is, for example, data consisting of target vehicle speeds associated with time for each target control position set at predetermined intervals on the route. The acceleration pattern is, for example, data consisting of target accelerations associated with time for each target control position set at predetermined intervals on the route. The steering pattern is, for example, data consisting of target steering torques associated with time for each target control position set at predetermined intervals on the route.

[0058] In addition, this driving plan includes a driving plan in which the host vehicle 100 follows a preceding vehicle. As an example, there are a conventionally known cruise control, an adaptive cruise control (ACC), and a communication cooperative adaptive cruise control (CACC) that performs follow-up control by vehicle-to-vehicle communication. The switching of the cruise control or the like is performed by an input operation switch group attached to the side of the steering wheel or the steering pad, and includes startup and stop of the system, switching of the control mode, input of the set vehicle speed, setting of the target inter-vehicle distance (for example, set in three levels: long, medium, and short), etc.

[0059] The travel control unit 47 is configured to automatically control the travel of the host vehicle 100 based on the travel plan generated by the travel plan generation unit 46. Specifically, a control signal corresponding to the travel plan is output to the engine 1, each motor 6, 18, or the actuator 42 via the drive controller 22 and the sub-controller 23. Thereby, the host vehicle 100 is automatically driven.

[0060] The auxiliary device control unit 48 is configured to automatically control the auxiliary device 41 based on the travel plan generated by the travel plan generation unit 46. Specifically, a control signal corresponding to the travel plan is output to the auxiliary device 41 such as a wiper, a headlight, a direction indicator, an air conditioner, and an audio device as necessary.

[0061] The presence / absence determination unit 49 determines whether there is a passenger in the host vehicle 100 and the preceding vehicle. Specifically, in the host vehicle 100, when the power switch, ignition key switch, or start button switch is operated to ON, when the seating sensor detects that a person is sitting on the seat, when the seat belt wearing sensor detects the wearing of the seat belt, or when the steering wheel is operated, the presence / absence of the passenger is determined based on the operation status or operating state of the devices provided in the vehicle interior. Also, a biological sensor or moving body detection sensor such as an infrared sensor or Doppler sensor may be provided to detect the body temperature and movement of the passenger, thereby determining whether there is a passenger in the vehicle. In the preceding vehicle, the information of the preceding vehicle is acquired by wireless communication through the above-described vehicle-to-vehicle communication, or the presence / absence of the passenger in the preceding vehicle is determined by an in-vehicle camera or the like in the host vehicle 100.

[0062] As described above, the host vehicle 100 shown in FIG. 1 can travel by so-called autonomous driving. In this autonomous driving, as described above, vehicles can transmit and receive information such as the positions and speeds of each other by vehicle-to-vehicle communication or the like, and use this information to perform platoon driving with the preceding vehicle or the following vehicle. Note that platoon driving refers to a form in which a plurality of vehicles travel in a group while maintaining their relative positions to each other.

[0063] In the platoon driving system according to the embodiment, in the case of autonomous driving in which adaptive cruise control (hereinafter referred to as ACC driving) is performed and the host vehicle 100 is driving alone without detecting a preceding vehicle, for example, as shown in FIG. 3, when a preceding vehicle 110 with a high windbreak effect such as a truck that has entered in front of the host vehicle 100 is detected, the host vehicle 100 follows the preceding vehicle 110 to perform platoon driving. As a result, compared with the case where the host vehicle 100 continues to drive alone during ACC driving, by shifting to platoon driving with the preceding vehicle 110 having a high windbreak effect such as the back area (projected area seen from the rear), vehicle shape, and stable driving performance, the driving resistance (such as air resistance) can be reduced by the windbreak effect, and the fuel consumption and electricity consumption of the host vehicle 100 can be improved.

[0064] Note that the detection of whether there is a preceding vehicle in front of the host vehicle 100 is performed using a millimeter-wave radar, an in-vehicle camera, or the like (within the range that can be detected by the millimeter-wave radar or the in-vehicle camera, for example, the inter-vehicle distance is 100 to 150 [m]).

[0065] In addition, the determination by the ECU 20 as to whether the preceding vehicle has a high windbreak effect is, for example, to photograph the preceding vehicle from the rear with an in-vehicle camera of the host vehicle 100, obtain the projected area of the preceding vehicle based on the photographed image, and determine that it is a preceding vehicle with a high windbreak effect when the projected area is equal to or greater than a predetermined value. Further, the detection and determination of the preceding vehicle with a high windbreak effect are not limited to the preceding vehicle 110 that has entered in front of the host vehicle 100 (front) in the same lane as the host vehicle 100 from a lane different from the lane in which the host vehicle 100 is driving as shown in FIG. 3. For example, a preceding vehicle in front (front or diagonally in front) that the host vehicle 100 can catch up to a certain detectable distance, or a preceding vehicle that overtakes the host vehicle 100 and is in front of the host vehicle 100 (diagonally in front) is detected, and it is determined whether the detected preceding vehicle has a high windbreak effect. Then, the host vehicle 100 may follow the preceding vehicle determined to have a high windbreak effect to perform platoon driving.

[0066] In the platooning system according to the embodiment, when platooning is performed by the leading vehicle 110 with a high windbreak effect and the host vehicle 100, as shown in FIG. 4, when the vehicle speed of the leading vehicle 110 (80 [km / h]) is higher than the ACC set vehicle speed of the host vehicle 100 (79 [km / h]), in other words, when the relative speed between the host vehicle 100 and the leading vehicle 110 is such that the host vehicle 100 moves away from the leading vehicle 110, the ECU 20 proposes to increase the ACC set vehicle speed of the host vehicle 100 by a predetermined increase amount, and for example, executes control to present it to the driver (passenger) using an information panel or the like which is a proposal device provided inside the host vehicle 100. Then, when the driver (passenger) permits an increase in the ACC set vehicle speed in response to the proposal, for example, by executing it from an operation panel inside the vehicle, the ECU 20 can execute ACC driving at the ACC set vehicle speed increased by the predetermined increase amount. As a result, it is possible to suppress the host vehicle 100 from being separated from the leading vehicle 110 and shift to platooning, and it is possible to improve the fuel consumption / electricity consumption of the host vehicle 100 due to the windbreak effect.

[0067] On the other hand, as shown in FIG. 5, when the vehicle speed of the leading vehicle 110 (80 [km / h]) is lower than the ACC set vehicle speed of the host vehicle 100 (81 [km / h]), in other words, when the relative speed between the host vehicle 100 and the leading vehicle 110 is such that the host vehicle 100 approaches the leading vehicle 110, the ECU 20 does not change the ACC set vehicle speed of the host vehicle 100.

[0068] FIG. 6 is a flowchart showing an example of control executed by the ECU 20 in the host vehicle 100 during ACC driving alone.

[0069] First, the ECU 20 detects a preceding vehicle 110 in front of the host vehicle 100 that is traveling alone in ACC mode (step S1). Next, the ECU 20 determines whether the windbreak effect of the preceding vehicle 110 is high (step S2). If the ECU 20 determines that the windbreak effect of the preceding vehicle 110 is low (No in step S2), it ends the series of controls without implementing a proposal to change the ACC set vehicle speed. On the other hand, if the ECU 20 determines that the windbreak effect of the preceding vehicle 110 is high (Yes in step S2), it determines whether the vehicle speed of the preceding vehicle 110 is higher than the ACC set vehicle speed of the host vehicle 100 (step S3). If the ECU 20 determines that the vehicle speed of the preceding vehicle 110 is not higher than (less than or equal to) the ACC set vehicle speed of the host vehicle 100 (No in step S3), it ends the series of controls without implementing a proposal to change the ACC set vehicle speed. On the other hand, if the ECU 20 determines that the vehicle speed of the preceding vehicle 110 is higher than the ACC set vehicle speed of the host vehicle 100 (Yes in step S3), it implements a proposal to increase the ACC set vehicle speed of the host vehicle 100 (step S4). Then, the ECU 20 ends a control example.

[0070] Also, in the host vehicle 100 according to the embodiment, when a preceding vehicle 110 with a high windbreak effect is located in front of the host vehicle 100 that is traveling alone in ACC mode and the vehicle speed of the preceding vehicle 110 is higher than the ACC set vehicle speed of the host vehicle 100, the ECU 20 may automatically perform control to increase the ACC set vehicle speed of the host vehicle 100. When the ECU 20 automatically changes the ACC set vehicle speed of the host vehicle 100 in this way, it is preferable to present the fact to, for example, an in-vehicle information panel or the like so that the driver (passenger) can recognize it.

[0071] FIG. 7 is a flowchart showing another example of control executed by the ECU 20 in the host vehicle 100 that is traveling alone in ACC mode.

[0072] First, the ECU 20 detects a preceding vehicle 110 in front of the host vehicle 100 while the ACC is in operation alone (step S11). Next, the ECU 20 determines whether the windbreak effect of the preceding vehicle 110 is high (step S12). If the ECU 20 determines that the windbreak effect of the preceding vehicle 110 is low (No in step S12), it ends the series of controls without changing the ACC set vehicle speed. On the other hand, if the ECU 20 determines that the windbreak effect of the preceding vehicle 110 is high (Yes in step S12), it determines whether the vehicle speed of the preceding vehicle 110 is higher than the ACC set vehicle speed of the host vehicle 100 (step S13). If the ECU 20 determines that the vehicle speed of the preceding vehicle 110 is not higher than (less than or equal to) the ACC set vehicle speed of the host vehicle 100 (No in step S13), it ends the series of controls without changing the ACC set vehicle speed. On the other hand, if the ECU 20 determines that the vehicle speed of the preceding vehicle 110 is higher than the ACC set vehicle speed of the host vehicle 100 (Yes in step S13), it performs control to automatically increase the ACC set vehicle speed of the host vehicle 100 (step S14). Then, the ECU 20 ends the control of an example.

[0073] As a result, it is possible to suppress the separation of the host vehicle 100 from the preceding vehicle 110 and maintain platoon running, so that the fuel consumption and power consumption of the host vehicle 100 due to the windbreak effect can be improved.

[0074] In the platooning system according to the embodiment, the external sensor 37 provided on the host vehicle 100 such as an in-vehicle camera, a radar, and a lidar functions as a detection device for detecting a preceding vehicle. Further, the relative speed between the host vehicle 100 and the preceding vehicle 110 can be obtained using, for example, a millimeter-wave radar or the like. Further, as the predetermined increase width when increasing the ACC set vehicle speed of the host vehicle 100, it is preferable to set it to +1 to 2 [km] with respect to the vehicle speed of the preceding vehicle 110, for example. Further, when the vehicle speed of the preceding vehicle 110 is equal to or higher than a predetermined speed (the preceding vehicle 110 is +10 [km / h] or higher than the host vehicle 100) with respect to the ACC set vehicle speed of the host vehicle 100, the ECU 20 does not change the ACC set vehicle speed of the host vehicle 100. Thereby, it is possible to suppress the deterioration of fuel consumption and power consumption due to excessive increase in the ACC set vehicle speed of the host vehicle 100.

[0075] Further, when the host vehicle 100 exceeds the speed limit of the driving lane in which the host vehicle 100 is traveling by increasing the ACC set vehicle speed of the host vehicle 100, the ECU 20 does not propose to increase the ACC set vehicle speed of the host vehicle 100 or automatically change the ACC set vehicle speed of the host vehicle 100. Further, when the vehicle speed of the preceding vehicle 110 exceeds the speed limit of either the preceding vehicle 110 or the host vehicle 100 in the driving lane, the ECU 20 does not propose to increase the ACC set vehicle speed of the host vehicle 100 or automatically change the ACC set vehicle speed of the host vehicle 100. Thereby, it is possible to suppress the transition to platooning in which either the preceding vehicle 110 or the host vehicle 100 exceeds the speed limit. Note that the speed limit information of the driving lane is obtained, for example, based on the position information of the host vehicle 100 received by the GPS receiver 38 and the map information of the map database 39, or obtained from a speed sign by an in-vehicle camera.

Explanation of Signs

[0076] 1 Engine 2 Rear wheels 3 Front wheels 4 Transmission 5 Input shaft 6 First motor 7 Clutch mechanism 8, 8a, 8b Friction plates 9 Transfer 10 Rear propeller shaft 11 Front propeller shaft 12 Rear differential gear 13 Drive shaft 14 Steering device 15 Braking device 16 Front differential gear 17 Drive shaft 18 Second motor 19 Power storage device 20 ECU 21 Main controller 22 Driving controller 23 Sub - controller 24 Internal sensor 25 Accelerator pedal 26 Accelerator sensor 27 Brake pedal 28 Brake sensor 29 Steering wheel 30 Steering angle sensor 31 Vehicle speed sensor 32 Longitudinal acceleration sensor 33 Lateral acceleration sensor 34 Yaw rate sensor 35 Shift lever 36 Shift sensor 37 External sensor 38 GPS receiver 39 Map database 40 Navigation system 41 Auxiliary equipment 42 Actuator 43 Vehicle position recognition unit 44 External situation recognition unit 45 Driving state recognition unit 46 Driving plan generation unit 47 Driving control unit 48 Auxiliary equipment control unit 49 Occupied / unoccupied judgment unit 100 Own vehicle 110 Leading vehicle

Claims

1. A platoon driving system comprising a control device for controlling the driving of a host vehicle in an adaptive cruise control that adjusts the vehicle speed of the host vehicle to follow a preceding vehicle at a certain interval, wherein when the host vehicle is traveling alone in the adaptive cruise control, a preceding vehicle with a high windbreak effect is detected by a detection device provided on the host vehicle in front of the host vehicle, and the vehicle speed of the preceding vehicle is higher than the ACC set vehicle speed set as the vehicle speed in the adaptive cruise control of the host vehicle, the control device uses a proposal device provided on the host vehicle to propose to the passenger of the host vehicle to increase the ACC set vehicle speed by a predetermined increase width. A platoon driving system characterized by that.

2. A platoon driving system comprising a control device for controlling the driving of a host vehicle in an adaptive cruise control that adjusts the vehicle speed of the host vehicle to follow a preceding vehicle at a certain interval, wherein when the host vehicle is traveling alone in the adaptive cruise control, a preceding vehicle with a high windbreak effect is detected by a detection device provided on the host vehicle in front of the host vehicle, and the vehicle speed of the preceding vehicle is higher than the ACC set vehicle speed set as the vehicle speed in the adaptive cruise control of the host vehicle, the control device automatically executes control to increase the ACC set vehicle speed by a predetermined increase width. A platoon driving system characterized by that.

3. The platoon driving system according to claim 1 or 2, wherein the control device does not change the ACC set vehicle speed when the relative speed between the host vehicle and the preceding vehicle is such that the host vehicle approaches the preceding vehicle.

4. The platoon driving system according to claim 1 or 2, wherein the predetermined increase width is +1 to 2 [km / h] with respect to the vehicle speed of the preceding vehicle.

5. The platoon driving system according to claim 1 or 2, wherein the control device does not change the ACC set vehicle speed when the vehicle speed of the preceding vehicle is faster than a predetermined speed with respect to the ACC set vehicle speed of the host vehicle.

6. The platoon driving system according to claim 1 or 2, wherein the control device does not change the ACC set vehicle speed when the vehicle speed of the preceding vehicle exceeds the speed limit of either the preceding vehicle or the host vehicle in the driving lane.

7. The control device obtains the projected area of the preceding vehicle based on an image obtained by photographing the preceding vehicle from behind by a photographing device provided on the host vehicle, and determines that the wind shielding effect of the preceding vehicle is high when the projected area is equal to or greater than a predetermined value. The platooning system according to claim 1 or 2, characterized in that.

Images