Vehicle control device and vehicle control program

Abstract

To provide a vehicle control device capable of executing following control in such a manner that energy consumption during driving can be reduced.SOLUTION: A processor 61 determines whether a preceding vehicle is a high-efficiency vehicle when detecting the preceding vehicle during constant-speed driving of adaptive cruise control. The high-efficiency vehicle is the vehicle in which an index indicating the level of energy efficiency following the driving such as stability of the driving speed, electricity consumption efficiency, fuel efficiency, and eco-driving degree satisfies a prescribed energy-saving condition. The processor 61 starts following control without requiring driver permission when the preceding vehicle is the high-efficiency vehicle, and, on the other hand, inquires of the driver whether to follow the preceding vehicle when the preceding vehicle is not the high-efficiency vehicle.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a vehicle control device capable of determining whether or not to drive while following a preceding vehicle. [Background technology]

[0002] The control that automatically adjusts the speed of the vehicle so that the vehicle follows the preceding vehicle is known as adaptive cruise control or preceding vehicle following control. Patent Document 1 discloses a technology that changes the settings in the preceding vehicle following control based on the shape of the preceding vehicle in order to suppress swaying. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2017-105250 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, a method for suppressing energy consumption during driving when performing control to follow the preceding vehicle is not considered. If the host vehicle follows another vehicle that frequently repeats deceleration and acceleration, the energy efficiency of the host vehicle may deteriorate.

[0005] The present disclosure has been made based on the above-mentioned viewpoint, and one of its objectives is to provide a vehicle control device capable of performing tracking control so as to reduce energy consumption during driving. [Means for solving the problem]

[0006] The vehicle control device disclosed herein includes a receiving unit (64) that receives information about a preceding vehicle, and a control unit (61) that is configured to be able to perform following control, which is control for causing the vehicle to travel so as to follow the preceding vehicle. The control unit is configured to determine, based on the information about the preceding vehicle, whether or not the preceding vehicle satisfies predetermined energy-saving conditions regarding energy efficiency while traveling, and to perform following control when it is determined that the preceding vehicle satisfies the energy-saving conditions.

[0007] In addition, the vehicle control program disclosed herein includes instructions to cause a computer to acquire information about a preceding vehicle, determine whether the preceding vehicle satisfies specified energy-saving conditions regarding energy efficiency while driving based on the information about the preceding vehicle, and perform following control, which is control for causing the host vehicle to drive in a manner to follow the preceding vehicle, if the preceding vehicle satisfies the energy-saving conditions.

[0008] According to the above device / program, the host vehicle operates to perform follow-up control when the preceding vehicle satisfies the energy-saving condition. This reduces the risk of the host vehicle being followed by another vehicle that is inefficient in energy efficiency, such as one that frequently repeats deceleration and acceleration. In other words, follow-up control can be performed to reduce energy consumption during driving.

[0009] In addition, the symbols in parentheses in the claims indicate a correspondence with the specific means described in the embodiments described below as one aspect, and do not limit the technical scope of the present disclosure. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing an overall view of a transportation system. [Diagram 2] FIG. 1 is a block diagram of an in-vehicle system. [Diagram 3] FIG. 2 is a functional block diagram of a vehicle control device. [Figure 4] 5 is a flowchart showing an example of operation of the vehicle control device when the host vehicle catches up with the preceding vehicle. [Diagram 5]FIG. 13 is a diagram showing an example of an image displayed when starting to follow the preceding vehicle. [Figure 6] 4 is a flowchart showing an example of the operation of the vehicle control device during manual driving. [Figure 7] 10 is a flowchart of a process for changing whether or not to follow the preceding vehicle depending on a set vehicle speed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiment. The configuration disclosed below may be modified in various ways without departing from the scope of the present disclosure. Various modified examples may be appropriately combined and implemented within the scope of no technical contradiction. The present disclosure also includes a configuration that is not explicitly shown and is formed by combining multiple modified examples. In the following description, components having the same function may be given the same name or the same symbol, and specific description thereof may be omitted. When only a part of the configuration is mentioned, the description described elsewhere may be applied to the other parts.

[0012] FIG. 1 is a diagram showing an overall picture of a transportation system to which the present disclosure is applied. As shown in FIG. 1, the transportation system includes, in addition to the subject vehicle 1, another vehicle 2, a roadside unit 3, and a server 4. The subject vehicle 1 is a vehicle equipped with an in-vehicle system 5 described below. The other vehicle 2 is a vehicle other than the subject vehicle 1. The other vehicle 2 may also be equipped with a system having substantially the same functions as the in-vehicle system 5. The roadside unit 3 and the server 4 are optional elements and may be omitted. In the present disclosure, the subject vehicle 1 and the other vehicles 2 are also collectively referred to as vehicles.

[0013] In the present disclosure, one or more other vehicles 2 traveling ahead of the host vehicle 1 are also referred to as forward vehicles. The forward vehicles are not limited to the preceding vehicle 2A, but may include a lateral forward vehicle 2B, a leading vehicle 2C, and the like. The preceding vehicle 2A means the vehicle closest to the host vehicle 1 among the forward vehicles traveling in the ego lane. In other words, the preceding vehicle 2A corresponds to the other vehicle 2 traveling in front of the host vehicle 1. The ego lane means the lane in which the host vehicle 1 is traveling on the road. The ego lane can also be called the host vehicle lane or the host vehicle driving lane. The lateral forward vehicle 2B is the vehicle closest to the host vehicle 1 among the forward vehicles traveling in the adjacent lane. The adjacent lane is a lane adjacent to the ego lane. The leading vehicle 2C means the other vehicle 2 traveling at the front of the vehicle group to which the preceding vehicle 2A belongs.

[0014] As described above, the area in front of the host vehicle includes the area diagonally forward. The area in front of the host vehicle may be interpreted as a range within a predetermined distance from the host vehicle 1 in front of the host vehicle. The predetermined distance here may be 150 m, 200, or 250 m, for example. The range in front of the host vehicle may be changed depending on the vehicle speed. The area in front of the host vehicle may be a range that the host vehicle 1 can reach within a predetermined time (3 or 4 seconds).

[0015] The vehicle 1 and the other vehicle 2 are configured to be able to perform short-range communication. In the present disclosure, short-range communication refers to wireless communication performed directly between devices without going through a wireless base station. The short-range communication is communication conforming to a predetermined wireless communication standard in which the practical communication distance is about 150 m or 250 m. The short-range communication standard may be any standard such as DSRC (Dedicated Short Range Communications), WAVE (Wireless Access in Vehicular Environment), and Cellular V2X (PC5 / SideLink), which are compatible with the IEEE802.11p standard. IEEE (registered trademark) is an abbreviation for the Institute of Electrical and Electronics Engineers, which means the Institute of Electrical and Electronics Engineers. Direct wireless communication between vehicles is also called vehicle-to-vehicle (V2V: Vehicle-to-Vehicle) communication.

[0016] The vehicle 1 and the other vehicle 2 may be configured to periodically broadcast a vehicle status message by short range communication. The vehicle status message is a message indicating the status of the sender. The vehicle status message may include sender information, sending time, current position, traveling direction, traveling speed, acceleration, steering angle, blinker / wiper operation status, etc. The vehicle status message may be a Cooperative Awareness Message (CAM) defined in ETSI TS 102 637-2 or a Basic Safety Message (BSM) defined in SAE J 2735.

[0017] Furthermore, the vehicle 1 and the other vehicle 2 may periodically transmit energy efficiency data, which is data indicating energy efficiency, through short-range communication. The energy efficiency data is data indicating the degree of energy consumption when traveling a certain distance, in other words, the energy efficiency during traveling. The energy efficiency data may be transmitted as a separate communication packet, or may be included in the vehicle state message described above. Details of the energy efficiency data will be described later.

[0018] The roadside unit 3 is a wireless communication device arranged along a road. The roadside unit 3 may be considered as a part of a traffic infrastructure. The roadside unit 3 is also called an RSU (Road Side Unit). The roadside unit 3 is configured to be able to perform short-range communication with a vehicle. Direct wireless communication between a vehicle and the roadside unit 3 may also be called vehicle-to-infrastructure (V2I) communication.

[0019] The roadside unit 3 may be configured to transfer data received from other vehicles 2 to the vehicle 1. The roadside unit 3 may transmit information about other vehicles 2 present around the vehicle 1 to the vehicle 1. The roadside unit 3 may also be configured to transmit data received from the vehicles to the server 4 and transmit data received from the server 4 to the vehicle 1.

[0020] The server 4 is a server arranged outside the host vehicle 1. The server 4 may be configured to be able to perform cellular communication with the host vehicle 1. The cellular communication is wireless communication conforming to LTE (Long Term Evolution), 4G, 5G, or the like. The cellular communication may be understood as communication using a mobile phone line. The server 4 may collect the driving state of each vehicle and evaluate the energy-saving driving degree of each vehicle. The energy-saving driving degree will be described later. The server 4 may be configured to distribute to the host vehicle 1 a data set indicating the energy-saving driving degree of another vehicle 2 located in front of the host vehicle 1.

[0021] The server 4 may perform the processes for calculating and distributing the energy-saving driving degree in cooperation with the roadside unit 3. The server 4 may collect the driving conditions of each vehicle via the roadside unit 3. In addition, the server 4 may distribute a data set indicating the energy-saving driving degree of another vehicle 2 located in front of the vehicle 1 to the vehicle 1 via the roadside unit 3. Note that the roadside unit 3 may be provided with a function for evaluating and distributing the energy-saving driving degree.

[0022] In the following, a case where the host vehicle 1 is an electric vehicle will be described. Of course, the host vehicle 1 may be an engine vehicle, a hybrid vehicle, or a fuel cell vehicle. An electric vehicle is a vehicle equipped with only a motor as a drive source. An engine vehicle is a vehicle equipped with only an engine as a drive source. A hybrid vehicle is a vehicle equipped with both an engine and a motor as drive sources.

[0023] <Overall configuration of in-vehicle system 5> The in-vehicle system 5 includes various components shown in Fig. 2. That is, the in-vehicle system 5 includes an external sensor 51, a vehicle state sensor 52, a wireless communication unit 53, a display device 54, an input device 55, a traveling actuator 56, and a vehicle control device 60.

[0024] The vehicle control device 60 may be connected to each of the above devices / sensors such as the external sensor 51 so as to be able to communicate with each other via an in-vehicle network. The in-vehicle network is a communication network built inside the vehicle. The standard of the in-vehicle network may be Controller Area Network (CAN is a registered trademark), Ethernet (registered trademark), FrexRay (registered trademark), or the like. Some of the devices / sensors may be directly connected to the vehicle control device 60 by dedicated signal lines. The connection form between the devices may be changed as appropriate.

[0025] The external sensor 51 is a sensor that detects an object that exists outside the vehicle 1. The external sensor 51 may be understood as a sensor that senses the surrounding environment of the vehicle 1. The external sensor 51 may be rephrased as a surroundings monitoring sensor, an object detection sensor, or an independent sensor.

[0026] The external sensor 51 is configured to detect the presence and position of a predetermined detection target. The detection target may include a moving object such as a pedestrian or another vehicle 2. The external sensor 51 may be a perimeter monitoring camera, a millimeter wave radar, a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging), or a sonar.

[0027] The in-vehicle system 5 may include a plurality of external sensors 51. The in-vehicle system 5 may include a plurality of perimeter monitoring cameras each having a different shooting direction and a plurality of millimeter wave radars as the external sensors 51. The perimeter monitoring camera is an in-vehicle camera arranged to capture an image in a predetermined direction outside the vehicle 1. The perimeter monitoring camera detects and identifies an object registered as a detection target from the captured image using a classifier to which deep learning is applied. The external sensor 51 may be configured to be capable of detecting three-dimensional structures such as road signs and traffic lights.

[0028] The external sensor 51 outputs detection result data to the vehicle control device 60. The detection result data may be data indicating the detection result of an object, that is, the position, moving speed, moving direction, and type of each detected object. The vehicle control device 60 may be configured to be able to perform a part of the process related to the identification (recognition) of the detected object. The vehicle control device 60 may perform a process of identifying any of the position, moving speed, moving direction, and type of the detected object based on the observation data input from the external sensor 51. The functional arrangement in the in-vehicle system 5 may be changed as appropriate. The observation data refers to video / image data generated by a camera, three-dimensional point cloud data generated by a LiDAR, received data of reflected waves acquired by a millimeter wave radar / sonar, and the like.

[0029] The vehicle state sensor 52 is a sensor that detects information related to the state of the host vehicle 1. The vehicle state sensor 52 may include a vehicle speed sensor, an acceleration sensor, a brake pedal sensor, an accelerator pedal sensor, and a shift sensor. The vehicle speed sensor is a sensor that detects the traveling speed of the host vehicle 1. The acceleration sensor is a sensor that detects the acceleration acting on the host vehicle 1. The acceleration sensor may be configured to detect longitudinal acceleration and lateral acceleration. The longitudinal acceleration is the acceleration acting in the fore-and-aft direction of the vehicle body. The lateral acceleration is the acceleration acting in the left-and-right direction of the vehicle body.

[0030] The brake pedal sensor is a sensor that detects the amount of depression of the brake pedal. The accelerator pedal sensor is a sensor that detects the amount of depression of the accelerator pedal. The amount of depression of the brake pedal / accelerator pedal means the amount by which the driver depresses the brake pedal / accelerator pedal. The amount of depression may also be called the stroke amount. The amount of depression may be expressed as an angle / pressure, etc. In this disclosure, the accelerator pedal and the brake pedal may be collectively referred to as pedals. The shift sensor is a sensor that outputs a signal indicating a shift position. The vehicle state sensor 52 may include a turn signal and a wiper sensor. The vehicle state sensor 52 outputs data indicating the detection result to the vehicle control device 60. The types of sensors provided in the in-vehicle system 5 may be designed appropriately, and it is not necessary to provide all of the above-mentioned sensors.

[0031] The wireless communication unit 53 is a device for the vehicle 1 to perform wireless communication with an external device. The external device may include some or all of the other vehicle 2, the roadside unit 3, and the server 4. The wireless communication unit 53 is configured to be able to perform short-range communication. The wireless communication unit 53 includes an antenna for short-range communication, a transmission / reception circuit, and a communication controller. The transmission / reception circuit is a circuit that performs signal processing related to modulation and demodulation. The communication controller is a microcomputer that executes processing related to short-range communication.

[0032] The wireless communication unit 53 outputs the data received from the other vehicle 2 to the vehicle control device 60. In addition, the wireless communication unit 53 transmits the data received from the vehicle control device 60 to the other vehicle 2 or the roadside unit 3. The wireless communication unit 53 receives the energy efficiency data transmitted from the other vehicle 2 and provides it to the vehicle control device 60. In addition, the wireless communication unit 53 can transmit the energy efficiency data of the host vehicle 1 to the other vehicle 2 or the roadside unit 3 based on the input data from the vehicle control device 60.

[0033] Furthermore, the wireless communication unit 53 may be configured to be capable of performing cellular communication. The wireless communication unit 53 may include an antenna, a transmission / reception circuit, and a controller for cellular communication. Furthermore, the wireless communication unit 53 may be configured to perform cellular V2X.

[0034] The display device 54 is a device that displays an image. The display device 54 may be a display provided in an instrument panel. The display device 54 may be realized using a liquid crystal display or an organic EL display. The display device 54 displays an image according to a signal input from the vehicle control device 60.

[0035] The input device 55 is a device for receiving an instruction operation from the driver to the in-vehicle system 5. The input device 55 may be a steering switch or a touch panel laminated on the display device 54. The steering switch is a switch provided on the spoke portion of the steering wheel. The in-vehicle system 5 may include multiple types of devices as the input device 55.

[0036] The input device 55 outputs an operation signal, which is an electric signal corresponding to the driver's operation, to the vehicle control device 60. The operation signal includes information indicating the contents of the driver's operation. The in-vehicle system 5 receives an instruction for changing the operation mode of the vehicle control device 60 via the input device 55. The instruction for changing the operation mode also includes an instruction for starting and ending driving assistance. In the present disclosure, an operation signal for instructing the start of driving assistance is also referred to as an assistance start instruction signal. Also, an operation signal for instructing the end of driving assistance is also referred to as an assistance end instruction signal. The switches for instructing the start and end of driving assistance may be provided separately or may be the same switch.

[0037] The in-vehicle system 5 may be configured to be able to obtain various instructions from the driver through voice recognition. A device for voice input such as a microphone may also be included in the input device 55. Note that an HCU (HMI Control Unit) may be interposed between the display device 54 and the vehicle control device 60. The HCU is a device that comprehensively controls the notification of information to the driver.

[0038] The traveling actuator 56 is an actuator for driving the host vehicle 1. The traveling actuator 56 includes a brake actuator, a power train, a steering actuator, and the like. The steering actuator may be an EPS (Electric Power Steering) motor. The power train may be an electric unit including a motor, an inverter, and a transaxle. The power train in an engine vehicle or a hybrid vehicle may be interpreted as a unit / system including an electronic throttle, an engine, and a transmission. A motor generator may also be interpreted as one of the traveling actuators 56.

[0039] The vehicle control device 60 is a device that controls the traveling actuator 56 based on the detection results of the external sensor 51, and thereby performs part of the driving operation on behalf of the driver. The vehicle control device 60 may be interpreted as a driving assistance ECU (Electronic Control Unit) that provides a driving assistance function. Note that other ECUs, such as a steering ECU that performs steering control, a power unit control ECU that performs acceleration / deceleration control, and a brake ECU, may be interposed between the vehicle control device 60 and the traveling actuator 56.

[0040] The vehicle control device 60 includes a computer. That is, the vehicle control device 60 includes a processor 61, a memory 62, a storage 63, a communication interface 64, and a bus connecting these. The memory 62 is a rewritable volatile storage medium. The memory 62 may be a RAM (Random Access Memory). The storage 63 is a rewritable non-volatile medium such as a flash memory. The storage 63 stores a vehicle control program which is a program executed by the processor 61. The execution of the vehicle control program by the processor 61 corresponds to the execution of a vehicle control method. The processor 61 corresponds to a control unit, and the communication interface 64 corresponds to a receiving unit.

[0041] When a driving assistance function is enabled based on a user operation, the vehicle control device 60 executes control as driving assistance. The control here may be rephrased as processing. The vehicle control device 60 may be configured to execute ACC (Adaptive Cruise Control) and LTC (Lane Trace Control) as driving assistance.

[0042] ACC is a control that automatically adjusts the traveling speed of the host vehicle 1 according to the traveling environment and a target value of the traveling speed set by the driver (hereinafter, set vehicle speed). In ACC, the vehicle control device 60 drives the host vehicle 1 at a constant speed at a set vehicle speed when the preceding vehicle 2A does not exist. In ACC, the vehicle control device 60 performs follow-up control when the preceding vehicle 2A exists. The follow-up control is a control that automatically adjusts the traveling speed of the host vehicle 1 within a speed range according to the set vehicle speed so as to keep the inter-vehicle distance between the preceding vehicle 2A and the host vehicle 1 constant. The follow-up control may be understood as a control that drives the host vehicle 1 so as to follow the preceding vehicle 2A. In this disclosure, a state in which the follow-up control is being performed is also referred to as a follow-up traveling state. In this disclosure, a state in which the host vehicle 1 is driven at a constant speed at a set vehicle speed is also referred to as a constant-speed traveling state. During ACC execution, the vehicle control device 60 can be in a constant-speed traveling state and a follow-up traveling state. The case where the preceding vehicle 2A does not exist may be interpreted as the case where the preceding vehicle 2A is not detected by the external sensor 51. The set vehicle speed may be set by the user within a preset speed range. The target value of the distance from the preceding vehicle 2A in the ACC (i.e., the target distance) may be determined according to the set vehicle speed. The vehicle control device 60 may be configured to be able to change the setting of the distance between the vehicles in three or four stages. The target distance between the vehicles may be determined based on the concept of inter-vehicle time. The set vehicle speed and the target distance between the vehicles may be changed based on an operation signal input from the input device 55. The set vehicle speed and the target distance between the vehicles specified by the driver may be stored in the storage 63 and automatically read out from the next time onwards.

[0043] LTC is a function that automatically controls the steering angle at all times so that the host vehicle 1 travels along the center of the ego lane, based on lane position information detected by the external sensor 51. Note that the vehicle control device 60 may be configured to execute LTA (Lane Tracing Assist) as a driving assistance function instead of or in addition to LTC. LTA is a control that assists steering so that the host vehicle 1 does not deviate from the ego lane, based on lane position information detected by the external sensor 51. LTA may be a function that applies a steering force in a direction toward the center of the ego lane only when the host vehicle 1 is about to deviate from the ego lane.

[0044] In addition, the vehicle control device 60 may be configured to automatically execute lane change to overtake the preceding vehicle 2A when an overtaking instruction is input from the driver while the driving assistance function is enabled. The automatic lane change may be understood as recognizing an empty space in the target lane and then moving the vehicle 1 laterally toward the empty space. The overtaking instruction may be pressing a specified switch or activating a turn signal. The automatic lane change corresponds to lane change control.

[0045] The vehicle control device 60 has a normal mode and an energy saving mode as operation modes when performing the above driving assistance. The energy saving mode is a mode in which acceleration and deceleration (i.e., speed adjustment) are performed so that the energy loss required for driving is smaller than in the normal mode, in other words, so that energy efficiency is increased. Energy saving is an abbreviation of energy saving. The energy saving mode may be a mode in which acceleration and deceleration are performed more gently than in the normal mode. In the energy saving mode, the vehicle control device 60 may be configured to set a longer inter-vehicle distance than in the normal mode. Furthermore, if the host vehicle 1 is an electric vehicle, in the energy saving mode, the vehicle control device 60 may be configured to decelerate the vehicle by regenerative braking as much as possible. The energy saving mode may be called a power saving mode or a power saving mode.

[0046] The vehicle control device 60 switches the operating state of the driving support function based on an operation signal input from the input device 55. The state of the vehicle control device 60 in which the driving support function is disabled is hereinafter also referred to as a pause mode. The pause mode may be a state in which the vehicle control device 60 does nothing, or may be a mode in which the vehicle control device 60 only notifies the driver of an object to be careful of. The pause mode may also be a state in which autonomous emergency braking (AEB) can be performed based on an output signal from the external sensor 51. AEB is a process in which the vehicle 1 is forcibly decelerated based on the presence of an object whose predicted time to collision (TTC: Time To Collision) is equal to or less than a predetermined value.

[0047] In addition, when the driving support function is enabled, the vehicle control device 60 switches between the normal mode and the energy saving mode based on an operation signal. The vehicle control device 60 displays an image indicating the operation state of the driving support function on the display device 54.

[0048] <Vehicle control device functions> 3 as functional units realized by executing a vehicle control program. That is, the vehicle control device 60 has a data acquisition unit F1, an environment recognition unit F2, a mode control unit F3, a host vehicle efficiency evaluation unit F4, a judgment unit F5, a confirmation unit F6, and a following control unit F7.

[0049] The data acquisition unit F1 is configured to receive various information for implementing driving assistance. The data acquisition unit F1 acquires sensing data (i.e., detection results) from the external sensor 51. The sensing data includes data on objects present around the vehicle, such as moving bodies, features, and obstacles. The data acquisition unit F1 may acquire information on the preceding vehicle 2A and the vehicle 2B ahead to the side from the external sensor 51. The data on each detected object may include the position, moving speed, and type or size of the detected object. The sensing data on the features may include data on the detection results of lane markings and road edges. The data on lane markings may include not only position data but also data indicating the line type (solid line or dashed line). The data acquisition unit F1 also acquires data indicating the state of the vehicle, such as the running speed and acceleration of the vehicle 1, from the vehicle state sensor 52.

[0050] Furthermore, the data acquisition unit F1 acquires data transmitted from an external device in cooperation with the wireless communication unit 53. The data acquisition unit F1 may acquire energy efficiency data and driving state messages transmitted from a preceding vehicle through vehicle-to-vehicle communication. The data acquisition unit F1 may also receive information on the preceding vehicle from the roadside unit 3 or the server 4.

[0051] The data acquisition unit F1 also acquires the driver's operations on the in-vehicle system 5 based on a signal from the input device 55. The data acquisition unit F1 acquires instruction signals relating to the start and end of driving assistance from the input device 55. Various data successively acquired by the data acquisition unit F1 is stored in a temporary storage medium such as a memory 62, and is used by the environment recognition unit F2, the judgment unit F5, etc.

[0052] The environment recognition unit F2 recognizes the driving environment of the vehicle 1 based on the data acquired by the data acquisition unit F1. The environment recognition unit F2 may recognize the driving environment of the vehicle 1 by a sensor fusion process. The sensor fusion process is a process of integrating the detection results of a plurality of external sensors 51, such as a perimeter monitoring camera and a millimeter wave radar, with a predetermined weight.

[0053] The driving environment includes the curvature of the road, the number of lanes, the ego lane number, the weather, the road surface condition, the traffic volume, the remaining distance to the gate point, etc. The ego lane number is a number indicating the position of the ego lane on the road, in other words, the number of other lanes existing on the left or right side of the host vehicle 1. The ego lane number may be expressed with the left road edge as the reference.

[0054] The driving environment includes the positions, types, and moving speeds of objects around the vehicle. The environment recognition unit F2 recognizes the position and behavior of the vehicle ahead based on various data acquired by the data acquisition unit F1. For example, the environment recognition unit F2 periodically acquires the driving speed and acceleration of the preceding vehicle 2A based on data received by the external sensor 51 and / or the wireless communication unit 53. The environment recognition unit F2 may identify and update information not only about the preceding vehicle 2A, but also about the lateral preceding vehicle 2B and / or the leading vehicle 2C based on data received by the external sensor 51 and / or the wireless communication unit 53.

[0055] The mode control unit F3 controls the operation mode of the vehicle control device 60 based on the operation signal received by the data acquisition unit F1. When an assistance start instruction signal is input from the input device 55, the mode control unit F3 switches the operation mode from the pause mode to the normal mode or the energy saving mode. In the following, "driving assistance is being performed" may be interpreted as a state in which the driving assistance function is enabled, that is, the vehicle control device 60 is operating in the normal mode or the energy saving mode. In addition, in the following, "manual driving" may be interpreted as a state in which the driving assistance (mainly the ACC) is stopped, that is, the vehicle control device 60 is in the pause mode.

[0056] Whether the vehicle control device 60 operates in the normal mode or the energy saving mode when the assistance start instruction signal is received may be preset by the driver via a predetermined setting screen. The storage 63 may store operation setting data indicating whether the operation mode immediately after the assistance start is the normal mode or the energy saving mode.

[0057] Of course, the mode control unit F3 may be configured to operate in the normal mode once when it receives a start instruction signal. The mode control unit F3 may switch the operation mode from the normal mode to the energy saving mode when the remaining power of the vehicle battery becomes less than a predetermined value while operating in the normal mode, or when it receives an operation signal for switching to the energy saving mode. The vehicle control device 60 may be configured to be able to acquire data indicating the remaining power based on the output voltage of the vehicle battery. In addition, the mode control unit F3 may switch the operation mode to the pause mode when an override operation by the driver is detected while driving assistance is being performed. The override operation may be depression of a pedal or the like.

[0058] The host vehicle efficiency evaluation unit F4 is configured to evaluate the energy efficiency of the host vehicle 1 when it travels. The energy efficiency may be expressed as electricity efficiency or fuel efficiency. The electricity efficiency may be calculated using the Worldwide harmonized Light duty driving Test Cycle (WLTC) method or the Environmental Protection Agency (EPA) method. The electricity efficiency and fuel efficiency may be average values ​​(average fuel efficiency or average electricity efficiency) per certain time or per certain distance. The electricity efficiency or fuel efficiency corresponds to the average energy efficiency.

[0059] Of course, the energy efficiency may be expressed using a parameter other than the fuel consumption / electricity consumption. The vehicle efficiency evaluation unit F4 may be configured to calculate an eco-driving degree as data representing the energy efficiency. The eco-driving degree may be interpreted as a parameter indicating the degree of energy consumption when traveling a certain distance, in other words, the energy efficiency required for traveling. The higher the eco-driving degree, the better the energy efficiency. The more unstable the speed is and the more frequently the brake actuator is driven, the lower the eco-driving degree may be. The eco-driving degree may be expressed as a score with 100 points as the maximum score, or may be expressed as a level. The vehicle efficiency evaluation unit F4 may calculate the eco-driving degree based on time-series data of acceleration, operation history of pedals, stability of speed, and the like. The eco-driving degree may be calculated by any method. Furthermore, the vehicle efficiency evaluation unit F4 may generate data indicating a change range of the traveling speed as data representing the energy efficiency. The change range of the traveling speed may be the difference between the maximum value and the minimum value of the speed within a certain time.

[0060] In this embodiment, the vehicle 1 shares energy efficiency data with the other vehicle 2 through vehicle-to-vehicle communication. The energy efficiency data is data that directly or indirectly indicates the vehicle's own energy efficiency. The vehicle 1 periodically transmits the energy efficiency data through short-range communication. The other vehicle 2 also periodically generates and transmits energy efficiency data, similar to the vehicle 1. The vehicle 1 may also receive energy efficiency data of the other vehicle 2 (mainly the vehicle ahead) from the roadside unit 3 or the server 4.

[0061] As described above, energy efficiency may be expressed as electricity consumption (fuel economy) or eco-driving level. When the energy efficiency data includes information on electricity consumption, the energy efficiency data may include a code indicating a method for calculating the electricity consumption. Each vehicle may periodically calculate the electricity consumption or fuel economy and transmit data indicating the latest electricity consumption or fuel economy as the energy efficiency data.

[0062] The energy efficiency data may include some or all of the variation range of the traveling speed, the speed history data, the acceleration history data, the brake history data, and the accelerator history data as data for the receiving vehicle to judge the energy efficiency. The speed history data may be time series data of the traveling speed within a recent fixed time. The variation range of the traveling speed corresponds to data that representatively (succinctly) represents the history of the traveling speed. The acceleration history data may be time series data of the acceleration acting on the vehicle. The acceleration history data may be data indicating the maximum, minimum, average, or median of the acceleration observed within a fixed time. The acceleration history data may include an acceleration amplitude value that is the difference between the maximum or minimum value and the average or median value of the acceleration. The acceleration history data may include the history of the deceleration. Furthermore, the acceleration history and the deceleration history may be separated. Low acceleration or deceleration, that is, stable acceleration, indicates high energy efficiency.

[0063] The braking history data may be time series data of the amount of depression of the brake pedal within a recent fixed period of time. The braking history data may include the maximum value, total value, or frequency of depression of the brake pedal within a recent fixed period of time. Deceleration causes greater energy loss than acceleration. Fewer deceleration operations indicate higher energy efficiency. The accelerator pedal operation history may be similar to the brake pedal operation history described above. Each vehicle may generate data indicating any energy efficiency and transmit it to other devices via short-range communication.

[0064] In addition, if the transmission source has a mode for automatic control of driving speed, i.e., an ACC operating mode that has a normal mode and an energy saving mode, the energy efficiency data may include data indicating whether or not the vehicle is driving in the energy saving mode.

[0065] The judgment unit F5 is configured to judge whether the preceding vehicle 2A satisfies energy saving conditions (hereinafter, energy saving conditions) based on the received data of the wireless communication unit 53 or the detection results of the external sensor 51. Determining that the preceding vehicle 2A satisfies the energy saving conditions corresponds to determining that the preceding vehicle 2A is a highly efficient vehicle. A highly efficient vehicle means a vehicle that has good energy efficiency for running. A highly efficient vehicle may be rephrased as an energy-efficient driving vehicle. The energy saving conditions may be interpreted as conditions for distinguishing whether the other vehicle 2 is one that the host vehicle 1 should follow from the viewpoint of energy efficiency, as described below, that is, as following conditions from the viewpoint of energy efficiency.

[0066] The judgment unit F5 may judge that the preceding vehicle 2A satisfies the energy saving condition when the maximum value of the acceleration or deceleration of the preceding vehicle 2A is smaller than the allowable acceleration. The allowable acceleration is a threshold parameter for judging whether the preceding vehicle 2A satisfies the energy saving condition. The allowable acceleration may be a constant value set in advance from the viewpoint of fuel consumption / electricity consumption. The allowable acceleration may also be the maximum value of the acceleration / deceleration of the host vehicle 1 within a certain period of time.

[0067] Furthermore, if the traveling speed of the preceding vehicle 2A is less than the permissible speed, it may be determined that the preceding vehicle 2A satisfies the energy saving condition. The lower the speed, the more the traveling resistance can be reduced. Therefore, as described above, if the speed is less than the permissible speed, it may be determined that the energy saving condition is satisfied. The permissible speed may be a fixed value (e.g., 80 km / h). The permissible speed may be changed according to the vehicle model of the host vehicle 1. If the vehicle model of the host vehicle 1 is a model that is less susceptible to air resistance, such as a sedan or coupe, the permissible speed may be set higher (e.g., 90 km / h) compared to models that are more susceptible to air resistance, such as a wagon or minivan.

[0068] The judgment unit F5 may compare the driving history of the host vehicle 1 with the driving history of the preceding vehicle 2A, and may determine that the preceding vehicle 2A satisfies the energy-saving condition if the similarity between the two is equal to or greater than a certain value, or if the preceding vehicle 2A is driving with better energy efficiency than the host vehicle 1. Driving with good energy efficiency may be interpreted as driving with small fluctuations in driving speed or driving with fewer braking events. The judgment unit F5 may determine that the preceding vehicle 2A satisfies the energy-saving condition if the range of change in speed of the preceding vehicle 2A is smaller than that of the host vehicle 1, or if the range of change in the driving speed of the preceding vehicle 2A is less than a predetermined value.

[0069] The vehicle control device 60 may receive data indicating the driving state of the preceding vehicle 2A, such as the driving speed and acceleration, from the preceding vehicle 2A via wireless communication as energy efficiency data or a driving state message. The vehicle control device 60 may also obtain the above data from sensing data of the external sensor 51.

[0070] Moreover, the judgment unit F5 may judge that the preceding vehicle 2A satisfies the energy saving condition when the electric power consumption / fuel consumption of the preceding vehicle 2A is equal to or higher than a predetermined threshold. Furthermore, the judgment unit F5 may judge that the preceding vehicle 2A satisfies the energy saving condition when the eco-driving degree of the preceding vehicle 2A is equal to or higher than a predetermined value. The judgment unit F5 may judge that the preceding vehicle 2A satisfies the energy saving condition when the preceding vehicle 2A is executing the ACC in the energy saving mode. When the preceding vehicle 2A is executing the ACC in the energy saving mode, this corresponds to a state in which the traveling of the preceding vehicle 2A is automatically controlled by a control device mounted on the preceding vehicle 2A so as to suppress the energy consumption required for the traveling of the preceding vehicle 2A. The above state may be interpreted as a state in which the preceding vehicle 2A is equipped with an ACC device equipped with an energy saving mode, that is, a control device equivalent to the vehicle control device 60, and the energy saving mode is enabled.

[0071] The vehicle control device 60 may obtain the electricity consumption / fuel consumption, eco-driving level, specific operation mode of the ACC, and the like of the preceding vehicle 2A as energy efficiency data via wireless communication. Of course, the vehicle control device 60 may receive the above-mentioned determination materials related to the energy saving conditions via the roadside device 3 or the server 4, rather than directly from the preceding vehicle 2A. In addition, the roadside device 3 or the server 4 may determine whether the preceding vehicle 2A satisfies the energy saving conditions and notify the host vehicle 1 of the determination result.

[0072] The determination unit F5 may determine whether the lateral front vehicle 2B and the leading vehicle 2C also satisfy the energy saving condition in the same manner as when determining whether the preceding vehicle 2A satisfies the energy saving condition. When there are multiple front vehicles, the determination unit F5 may determine whether each of the multiple front vehicles satisfies the energy saving condition.

[0073] Furthermore, when multiple forward vehicles are detected, the determination unit F5 may calculate an energy-saving driving degree (hereinafter, energy-saving driving degree) for each of them. The energy-saving driving degree is a parameter indicating the degree of energy efficiency involved in driving. When the determination unit F5 is able to receive the eco-driving degree of the other vehicle 2 via wireless communication, the determination unit F5 may adopt the eco-driving degree as the energy-saving driving degree. However, it is also assumed that the calculation formula for the eco-driving degree differs for each other vehicle 2. In response to this, the energy-saving driving degree may be understood as a parameter corresponding to the eco-driving degree, which is calculated using a predetermined calculation formula registered in the vehicle control device 60.

[0074] The determination unit F5 may determine that the vehicle that is executing the ACC in the energy saving mode among the multiple vehicles ahead is the most efficient vehicle. The most efficient vehicle refers to the vehicle that has the highest energy efficiency among the vehicles ahead. In other words, the most efficient vehicle is the vehicle that has the highest degree of energy saving driving.

[0075] If there is no vehicle running ACC in energy saving mode among the multiple forward vehicles, the determination unit F5 may determine the vehicle with the highest eco-driving level as the most efficient vehicle. If the determination unit F5 cannot determine the most efficient vehicle from the viewpoint of the ACC operation mode and the eco-driving level, the determination unit F5 may determine the vehicle with the best electric efficiency or fuel economy as the most efficient vehicle. If the forward vehicles include a hybrid vehicle or an engine vehicle, the determination unit F5 may determine the most efficient vehicle after converting the fuel economy into electric efficiency using a predetermined conversion formula. In addition, the determination unit F5 may determine the most efficient vehicle as the vehicle with the smallest speed change range within a recent certain period of time or the vehicle with the fewest number of brakes.

[0076] The confirmation unit F6 is configured to execute a process (hereinafter, intention confirmation process) of inquiring of the driver whether or not to follow the preceding vehicle 2A when driving assistance is being performed and the preceding vehicle 2A does not satisfy the energy saving condition. The confirmation unit F6 notifies the following control unit F7 of data indicating the result of the inquiry. The confirmation unit F6 may present the driver with multiple options, such as (1) overtaking (changing lanes) or (2) switching to manual driving, as options for not following the preceding vehicle 2A. Switching to manual driving corresponds to stopping the driving assistance function. The intention confirmation process may be executed using an in-vehicle HMI (Human Machine Interface) such as the display device 54 and the input device 55. The driver's response to the inquiry may be acquired via the input device 55.

[0077] The following control unit F7 is configured to perform control for automatically driving the host vehicle 1 so as to follow the preceding vehicle 2A. The following control unit F7 may be configured to start automatic lane change for overtaking when a response indicating that the driver wishes to overtake is acquired as a result of the intention confirmation process.

[0078] In addition, when traveling on a road with two or more lanes on each side, and when the vehicle 2B ahead of the side has a higher energy-saving driving degree than the preceding vehicle 2A, the following control unit F7 may be configured to change lanes to the lane in which the vehicle 2B ahead of the side is traveling. When the most efficient vehicle and the host vehicle 1 are traveling in different lanes, the following control unit F7 may change lanes so that the host vehicle 1 and the most efficient vehicle are traveling in the same lanes.

[0079] <Example of operation> Here, the operation of the vehicle control device 60 during execution of driving assistance will be described with reference to the flowchart shown in Fig. 4. The flowchart shown in Fig. 4 may be executed periodically (for example, every 250 milliseconds) during constant speed traveling in ACC.

[0080] 4 includes, as an example, steps S101 to S111. The processor 61 as an entity executing the following steps may be replaced with the vehicle control device 60, or, depending on the context, the data acquisition unit F1, the environment recognition unit F2, the mode control unit F3, the host vehicle efficiency evaluation unit F4, the determination unit F5, the confirmation unit F6, or the following control unit F7.

[0081] Step S101 is a step in which the processor 61 acquires various data. In step S101, the processor 61 acquires sensing data from the external sensor 51, detection results from the vehicle state sensor 52, received data from the wireless communication unit 53, and the like. Note that the process corresponding to step S101 may be executed periodically (e.g., every 100 milliseconds) or whenever necessary, independent of this flow. Step S101 may be a step in which data stored in the memory 62 (i.e., data that has already been acquired) is read out.

[0082] Step S102 is a step for determining whether or not a preceding vehicle 2A exists based on the data acquired or read out in step S101. If a preceding vehicle 2A does not exist (S102 NO), the processor 61 continues control for constant speed traveling at the set vehicle speed that has been set (S111). On the other hand, if a preceding vehicle 2A exists, an affirmative determination is made in step S102, and the process proceeds to step S103.

[0083] The process from step S103 onward may be understood as a process when the vehicle catches up with a vehicle traveling ahead during constant speed driving in ACC, for example. When the distance between the other vehicle 2 traveling outside the detection range of the external sensor 51 on the ego lane and the host vehicle 1 decreases and the other vehicle 2 enters the detection range of the external sensor 51, step S102 may be determined as positive. Also, step S102 may be determined as positive when another vehicle 2 enters in front of the host vehicle 1 from an adjacent lane.

[0084] Step S103 is a step in which the processor 61 determines whether or not the energy efficiency data of the preceding vehicle 2A has been received by wireless communication. If the energy efficiency data of the preceding vehicle 2A has been received, the result of step S103 is YES and the process proceeds to step S105. On the other hand, if the energy efficiency data of the preceding vehicle 2A has not been received, the result of step S103 is NO and the process proceeds to step S104.

[0085] Step S104 is a step in which the processor 61 executes an efficiency evaluation process for the preceding vehicle 2A. The efficiency evaluation process is a process for evaluating the energy efficiency of the traveling of the preceding vehicle 2A based on time series data of the speed and acceleration of the preceding vehicle 2A detected by the external sensor 51. Step S104 may be continued for a certain period of time so that a number of speed and acceleration samples are collected that enable a determination as to whether the preceding vehicle 2A satisfies the energy saving condition. During execution of step S104, the processor 61 may temporarily make the host vehicle 1 follow the preceding vehicle 2A. The efficiency evaluation process may include evaluating the stability of the speed and the degree of energy saving driving by monitoring the behavior of the preceding vehicle 2A for a certain period of time.

[0086] In addition, when the efficiency evaluation process is being executed, if energy efficiency data of the preceding vehicle 2A is received from the preceding vehicle 2A, the roadside unit 3, or the server 4 (hereinafter referred to as the preceding vehicle 2A, etc.), the processor 61 may interrupt the efficiency evaluation process and proceed to step S105.

[0087] Step S105 is a step in which the processor 61 determines whether the preceding vehicle 2A satisfies the energy saving conditions based on the received energy efficiency data of the preceding vehicle 2A or the result of the efficiency evaluation process. The processor 61 may determine that the preceding vehicle 2A satisfies the energy saving conditions when the preceding vehicle 2A is executing ACC in energy saving mode, when the eco-driving level is equal to or greater than a predetermined value, or when the change in speed is less than a predetermined value. The processor 61 may determine that the preceding vehicle 2A satisfies the energy saving conditions when the preceding vehicle 2A satisfies one or more of the various conditions described above.

[0088] If the preceding vehicle 2A satisfies the energy saving condition (S105 YES), the process proceeds to step S106. In step S106, the processor 61 starts following the preceding vehicle 2A. When step S106 is completed, the process proceeds to step S107. In step S107, the processor 61 displays a following notification image on the display device 54. The following notification image may be an image indicating that the preceding vehicle is being followed and that the preceding vehicle 2A is a vehicle that runs with good energy efficiency (i.e., a highly efficient vehicle). The following notification image may include an image element E1 indicating a highly efficient vehicle, an image element E2 indicating the host vehicle 1, and a lane marking E3 indicating a lane, as shown in FIG. 5. The fact that the preceding vehicle 2A is a highly efficient vehicle may be expressed by using an image element E11 that resembles a leaf, for example.

[0089] In this way, when the preceding vehicle 2A is a highly efficient vehicle, the preceding vehicle 2A automatically starts following the preceding vehicle 2A without asking the driver whether or not to follow the preceding vehicle 2A. This reduces the risk of causing inconvenience to the driver.

[0090] On the other hand, if the preceding vehicle 2A does not satisfy the energy saving condition (S106 NO), the process proceeds to step S108. Step S108 is a step for executing the intention confirmation process. In step S108, the processor 61 displays a predetermined confirmation image on the display device 54 together with outputting a predetermined notification sound. The confirmation image may be an image including a message inquiring whether to follow the preceding vehicle 2A that is not energy efficient. The confirmation image may include text or an icon image indicating that following driving is not recommended from the viewpoint of energy efficiency. The confirmation image may include, as options, a button for permitting following, a button for instructing overtaking, and a button for terminating ACC (driving assistance). The buttons here may be interpreted as image elements or options. The processor 61 may be configured to be capable of acquiring the driver's answer based on the touch panel operation, steering switch operation, or voice input by the driver while the message image is being displayed.

[0091] The processor 61 may be configured to determine that an automatic overtaking instruction has been input based on the driver activating a turn signal after the message image is displayed. The processor 61 may be configured to determine that an instruction to end the driving assistance has been input based on the driver depressing the accelerator pedal or the brake pedal after the message image is displayed. If no response is received from the driver even after a certain time has elapsed since the message image was displayed, the processor 61 may be configured to determine that permission to follow the preceding vehicle 2A has been obtained.

[0092] When permission to follow the preceding vehicle 2A is obtained as the driver's response to the intention confirmation process (S109 YES), the processor 61 executes steps S106 to S107. On the other hand, when permission to follow the preceding vehicle 2A is not obtained as the driver's response to the intention confirmation process (S109 NO), the process proceeds to step S110. Step S110 is a step in which the processor 61 executes control according to the driver's instruction. For example, when an overtaking instruction is input, the processor 61 starts a process for automatically executing a lane change for overtaking. Also, when an instruction to end the driving assistance is input, the processor 61 may transition the operation mode of the vehicle control device 60 to a sleep mode.

[0093] The vehicle control device 60 may periodically evaluate the energy-saving driving level of the preceding vehicle 2A not only when the preceding vehicle 2A has been caught up with, but also during following travel, and may execute steps S105 to S110 based on the evaluation result. In this case, step S106 may be to continue the following state. The processor 61 may be configured to end the following travel state or execute an intention confirmation process based on the preceding vehicle 2A no longer satisfying the energy-saving condition.

[0094] Furthermore, in the pause mode, the vehicle control device 60 may execute a following-start proposal process shown in Fig. 6. The following-start proposal process is a process for proposing the start of driving assistance (mainly ACC), and may include steps S201 to S206 as shown in Fig. 6. The processor 61 may start the following-start proposal process periodically (for example, every 500 milliseconds) during manual driving.

[0095] Steps S201 to S205 are the same as steps S101 to S105 described above, and therefore the description will be omitted. If the preceding vehicle 2A does not exist during manual driving (S202 NO), this flow may be ended. Step S205 is a step for determining whether the preceding vehicle 2A satisfies the energy saving condition during manual driving based on the received data from the external device or the sensing data of the external sensor 51. If the preceding vehicle 2A satisfies the energy saving condition (S205 YES), the processor 61 proposes to enable the driving assistance (S206). The proposal may include notifying that the preceding vehicle 2A is a high-efficiency vehicle. With this configuration, the ACC of the host vehicle 1 is likely to be started on the condition that the preceding vehicle 2A is a high-efficiency vehicle. As a result, the convenience of the driver and the energy efficiency of the host vehicle 1 may be improved.

[0096] On the other hand, if the preceding vehicle 2A does not satisfy the energy saving condition during manual driving (S205 NO), the processor 61 may end this flow without making any suggestion. Note that if the preceding vehicle 2A does not satisfy the energy saving condition (S205 NO), the processor 61 may suggest changing lanes or overtaking the preceding vehicle 2A. This is because when traveling behind a low-efficiency vehicle, the energy efficiency of the host vehicle 1 may decrease due to the influence of the behavior of the low-efficiency vehicle even during manual driving. According to a configuration that suggests overtaking or the like when it is determined that the energy saving driving level of the preceding vehicle 2A is less than a predetermined value, the energy saving driving level of the host vehicle 1 can be increased.

[0097] <Effects> According to the above configuration, it is possible to reduce the risk of the host vehicle 1 following a vehicle (hereinafter, a low-efficiency vehicle) that is traveling in an energy-inefficient manner against the driver's will. This reduces the deterioration of the improvement of the electric power consumption / fuel consumption of the host vehicle 1 due to the behavior of the preceding vehicle 2A. Furthermore, according to the above configuration, the host vehicle 1 preferentially follows a highly efficient vehicle, so that the electric power consumption / fuel consumption can be improved. In this case, the processor 61 itself does not need to perform complex calculations and controls for improving the electric power consumption. The processor 61 only needs to reproduce the behavior of the preceding vehicle 2A. Therefore, according to the configuration of the present disclosure, even if the performance of the processor 61 / vehicle system 5 is low, it may be possible to make the host vehicle 1 travel in an energy-efficient manner.

[0098] <Modification> In the above, a case has been described in which, when the preceding vehicle 2A satisfies the energy saving conditions (YES in S105), following travel is started without confirming the driver's intention, but the operation of the processor 61 is not limited to this. In other embodiments, the processor 61 may perform intention confirmation processing. When the preceding vehicle 2A satisfies the energy saving conditions, the processor 11 may display on the display device 54 an image recommending following travel of the preceding vehicle.

[0099] In addition, whether or not to automatically start following travel when catching up with another vehicle 2 that satisfies the energy saving condition may be pre-registered by the driver via a predetermined setting screen. That is, the vehicle control device 60 may be configured so that the driver can pre-register the system response when catching up with another vehicle 2 that satisfies the energy saving condition during driving assistance execution. The state in which it is pre-registered to automatically start following travel when catching up with another vehicle 2 that satisfies the energy saving condition is also included in the case in which the receiving unit has already received a signal that permits following control.

[0100] Furthermore, the vehicle control device 60 may be configured to allow the driver to pre-register the system response when catching up with another vehicle 2 that does not satisfy the energy saving condition during driving assistance execution. When catching up with another vehicle 2 that does not satisfy the energy saving condition, whether to follow the other vehicle 2, overtake the other vehicle 2, or switch to manual driving may be pre-registered by the driver via a predetermined setting screen. The processor 61 may operate according to a preset response policy.

[0101] The processor 61 controls the speed of the host vehicle 1 based on the set vehicle speed. Even if the preceding vehicle 2A is a high-efficiency vehicle, if the speed of the preceding vehicle 2A is significantly lower than the set vehicle speed, the convenience for the driver may be reduced if the host vehicle 1 is made to follow the preceding vehicle 2A. For this reason, the processor 61 may change the system response according to the speed of the preceding vehicle 2A.

[0102] For example, when the preceding vehicle 2A satisfies the energy saving condition (FIG. 7, S301, YES), the processor 61 may determine whether or not the speed difference between the speed of the preceding vehicle 2A and the set vehicle speed of the host vehicle 1 is within a predetermined allowable range (S302). The allowable range for the speed difference may be designed by the designer of the vehicle control device 60 or may be registered in the driver. The allowable range may be 10 km / h or 15 km / h. When the speed difference is within the allowable range (S302, YES), the processor 61 may start following traveling (S303). On the other hand, when the preceding vehicle 2A does not satisfy the energy saving condition (S301, NO) or when the speed difference is outside the allowable range (S302, NO), the processor 61 may perform an intention confirmation process (S304). After S304, the processor 61 may perform a process according to the driver's response to the intention confirmation process. In the intention confirmation process when the preceding vehicle 2A satisfies the energy saving condition but the speed difference is outside the allowable range, it may be notified that the speed is slow but the electricity cost / fuel cost will be improved.

[0103] The system response when the preceding vehicle 2A satisfies the energy saving condition but the speed difference is outside the allowable range may be registered in advance by the driver via a setting screen. For example, data indicating a response policy when the preceding vehicle 2A satisfies the energy saving condition but the speed difference is outside the allowable range may be registered in the storage 64 via the input device 55 and the setting screen. As the response policy, any one of the following may be registered: to have the system perform an intention confirmation process, to start following driving without intention confirmation, or to start overtaking without intention confirmation. The processor 61 may operate according to the response policy data registered in advance.

[0104] The set vehicle speed may reflect the driver's thoughts / preferences regarding vehicle driving. That is, when the set vehicle speed is relatively low, the driver may have the idea of ​​prioritizing energy efficiency over travel time. On the other hand, when the set vehicle speed is relatively high, the driver is likely to attach more importance to shortening travel time than energy efficiency. Based on such an idea, the processor 61 may be configured to omit the determination of whether the energy saving condition is satisfied or not when the set vehicle speed is equal to or higher than a predetermined value (e.g., 100 km / h). In a setting in which the determination of whether the preceding vehicle 2A is a high-efficiency vehicle or not is omitted, the processor 61 may determine whether to follow or overtake the preceding vehicle 2A based on the speed difference. The processor 61 may be configured to implement the above-mentioned embodiment and modified example only when the set vehicle speed is less than a predetermined value.

[0105] The present disclosure may be applied to a vehicle capable of performing automatic driving. The vehicle control device 60 may be an ECU (so-called automatic driving device) that provides an automatic driving function. The above-mentioned ACC or driving assistance may be replaced with automatic driving. This is because automatic driving also includes automatic adjustment of the driving speed. The processor 61 may perform the processing of steps S103 to S110 when catching up with the preceding vehicle 2A during automatic driving. During automatic driving, the processing of steps S108 to S110 may start control to automatically overtake the preceding vehicle 2A without confirming the driver's intention.

[0106] The level referred to by "autonomous driving" in this disclosure may be equivalent to level 3 defined by the Society of Automotive Engineers (SAE International), or level 4 or higher. Level 3 refers to a level where the system executes all driving tasks within the operational design domain (ODD), while the system transfers the operation authority to the user in an emergency. The ODD specifies the conditions under which autonomous driving can be executed, such as the driving position being within a motorway. Level 3 corresponds to a level where the driver needs to take over driving operations based on a request from the system. A motorway means a road where pedestrians and bicycles are prohibited from entering, such as a highway. Level 4 can be interpreted as a level where the system can execute all driving tasks, except under specific circumstances such as roads that cannot be handled and extreme environments. Level 5 is a level where the system can execute all driving tasks in any environment.

[0107] The processor 61 may be configured to follow the preceding vehicle 2A when the leading vehicle 2C, not the preceding vehicle 2A, satisfies the energy saving condition. Even if the energy efficiency of the preceding vehicle 2A itself is not high temporarily, the energy efficiency of the preceding vehicle 2A can be expected to improve due to the influence of the leading vehicle 2C. From a long-term perspective, the energy efficiency of the preceding vehicle 2A can become similar to that of the leading vehicle 2C. In such a case, the processor 61 may decide whether to follow the preceding vehicle 2A depending on the energy efficiency of the leading vehicle 2C. In particular, when the energy saving driving degree of the preceding vehicle 2A is unknown and it has been acquired from the roadside device 3 or the like that the leading vehicle 2C is a high-efficiency vehicle, the host vehicle 1 may be made to follow the preceding vehicle 2A based on the above idea.

[0108] <Additional remarks> The various flowcharts shown in this disclosure are merely examples, and the number of steps constituting the flowcharts and the order of execution of the processes can be changed as appropriate. The controls shown in each flowchart may be combined / executed in parallel to the extent that there is no contradiction. Expressions such as acquisition, determination, detection, generation, and calculation may be used interchangeably. When a certain device acquires certain data, it also includes the device generating the data based on a signal input from another device / sensor.

[0109] The apparatus, system, and methods thereof described in the present disclosure may be realized by a dedicated computer comprising a processor programmed to execute one or more functions embodied in a computer program. The apparatus and methods described in the present disclosure may be realized by using a dedicated hardware logic circuit. The apparatus and methods described in the present disclosure may be realized by one or more dedicated computers configured by a combination of a processor that executes a computer program and one or more hardware logic circuits. The processor may be any computing core such as a CPU, MPU, GPU, or DFP (Data Flow Processor). Some or all of the functions of the processor 61 may be realized as hardware. Some or all of the functions of the processor 61 may be realized by using any of a system-on-chip (SoC), an integrated circuit (IC), and a field-programmable gate array (FPGA).

[0110] The computer program includes instructions to be executed by a computer. The computer program may be stored in a computer-readable non-transitive tangible storage medium. The storage medium for the computer program may be a variety of media, such as a hard-disk drive (HDD), a solid-state drive (SSD), or a flash memory. [Explanation of symbols]

[0111] 1 Vehicle 1, 2A preceding vehicle, 5 in-vehicle system, 51 external sensor, 53 wireless communication unit, 54 display device, 55 input device, 60 vehicle control device, 61 processor (control unit), 62 memory, 63 storage, 64 communication interface (receiving unit)

Claims

1. a receiving unit (64) for receiving information on a preceding vehicle; a control unit (61) configured to be capable of performing a following control that causes the host vehicle to travel so as to follow the preceding vehicle, The control unit is determining whether the preceding vehicle satisfies a predetermined energy-saving condition regarding energy efficiency during traveling based on the information of the preceding vehicle; The vehicle control device is configured to perform the following control when it is determined that the preceding vehicle satisfies the energy saving condition.

2. The vehicle control device according to claim 1, The control unit is When the preceding vehicle satisfies the energy saving condition, the following control is automatically started without inquiring of the driver's intention, while When the preceding vehicle does not satisfy the energy saving condition, the vehicle control device executes a process of inquiring of the driver as to whether or not to change lanes or to execute the following control.

3. The vehicle control device according to claim 1, The control unit is a vehicle control device configured to execute a process for notifying a driver of information that does not recommend performing the following control using a notification device when the preceding vehicle does not satisfy the energy saving condition.

4. The vehicle control device according to claim 1, The control unit is configured to execute a process for notifying a driver of information recommending that the following control be performed using a notification device when the preceding vehicle satisfies the energy saving condition.

5. The vehicle control device according to claim 1, The receiving unit is configured to receive a signal indicating that the driver allows the following control via an input device, The control unit is The vehicle control device is configured such that, when the preceding vehicle satisfies the energy saving condition and the receiving unit receives a signal permitting the following control, the control unit performs the following control.

6. The vehicle control device according to claim 1, The vehicle control device, wherein the energy saving condition includes a state in which the traveling of the preceding vehicle is automatically controlled by a control device mounted on the preceding vehicle so as to reduce energy consumption required for the traveling of the preceding vehicle.

7. The vehicle control device according to claim 1, The energy-saving condition includes an energy-saving driving level indicating a degree of energy efficiency for the current traveling of the preceding vehicle being equal to or higher than a predetermined value.

8. The vehicle control device according to claim 1, The energy saving condition includes an average energy efficiency based on an energy consumption history of the preceding vehicle being equal to or greater than a predetermined value.

9. The vehicle control device according to claim 1, The energy saving condition includes a condition that a vehicle speed of the preceding vehicle is within a predetermined speed range.

10. The vehicle control device according to claim 1, The energy saving condition includes a condition that a maximum value of the acceleration of the preceding vehicle within a recent certain period of time falls within a predetermined range.

11. The vehicle control device according to claim 1, The receiving unit is configured to receive information about a plurality of other vehicles traveling ahead of the host vehicle, The control unit is determining an energy-saving driving level, which is a parameter indicating a degree of energy efficiency required for driving, for each of the other vehicles based on the information of the other vehicles; A vehicle control device, wherein when there are multiple other vehicles in front of the host vehicle, the control unit is configured to cause the host vehicle to follow a most efficient vehicle among the multiple other vehicles, which is the other vehicle that satisfies the energy-saving conditions and has the highest degree of energy-saving driving.

12. The vehicle control device according to claim 11, The control unit is The vehicle is configured to be capable of performing lane change control, which is a control for automatically changing a driving lane of the vehicle, a vehicle control device that, when the most efficient vehicle and the host vehicle are traveling in different lanes, performs the lane change control so that the host vehicle and the most efficient vehicle are traveling in the same lanes.

13. The vehicle control device according to claim 1, When a plurality of other vehicles are present ahead of the host vehicle on the travel lane of the host vehicle, the receiving unit acquires information on a leading vehicle that is traveling ahead of the plurality of other vehicles, The control unit is determining whether the leading car satisfies the energy saving condition; A vehicle control device characterized in that, when the leading vehicle satisfies the energy saving condition, the following control is performed.

14. The vehicle control device according to claim 1, The vehicle control device according to claim 1, wherein the receiving unit acquires the information about the preceding vehicle through wireless communication with the preceding vehicle, a roadside device, or a server.

15. The vehicle control device according to claim 1, The vehicle control device is characterized in that the receiving unit acquires the information on the preceding vehicle from an external sensor (51) provided in the host vehicle.

16. On the computer, Obtaining information about a preceding vehicle; determining whether the preceding vehicle satisfies a predetermined energy saving condition regarding energy efficiency during traveling based on the information of the preceding vehicle; and performing a following control, which is a control for causing the host vehicle to travel so as to follow the preceding vehicle, when the preceding vehicle satisfies the energy saving condition.

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