Vehicle driving control device

Abstract

To provide a travel control device of a vehicle which can obtain, when performing travel control in consideration of other surrounding vehicles, excellent riding comfortability, contributing to improve fuel economy, and contributing to safety travel.SOLUTION: A travel control device of a vehicle comprises: a surrounding information acquisition device 20, 21; an own vehicle condition information acquisition device 33; an external information receiving device 17; a set vehicle speed value setting part 22c which sets a target vehicle speed value; and a travel control unit 22 which performs travel control by controlling a vehicle speed value of the own vehicle in consideration of other surrounding vehicles on the basis of multiple pieces of information acquired from the surrounding information acquisition device, the own vehicle condition information acquisition device, and the external information receiving device. The travel control unit sets a vehicle speed value of the own vehicle which is obtained by deducting a prescribed value from vehicle speed value of a preceding vehicle as a temporary set vehicle speed value and performs travel control by use of the temporary set vehicle speed, when the preceding vehicle is recognized, the own vehicle speed exceeds the limited speed value or a prescribed speed value of the limited speed value reference, the driver set vehicle speed value is a vehicle speed value of the preceding vehicle or more, and a subsequent vehicle has not been continuously recognized for a prescribed hours or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a driving control device that controls the driving of a vehicle by taking into account other surrounding vehicles. [Background technology]

[0002] In recent years, in the field of vehicles such as automobiles, automatic driving control technology has been developed to automatically drive the vehicle without the driver's operation. In addition, various proposals have been made for vehicle driving control devices to assist the driver's driving operation by utilizing such automatic driving control technology, with the aim of reducing the burden of the driver's driving operation and improving safety when driving the vehicle, and these devices are generally being put into practical use.

[0003] For example, a conventional vehicle cruise control device is equipped with a surrounding environment recognition device using autonomous sensor devices such as a camera, a radar device, and a sonar device. Conventional cruise control devices of this type use these autonomous sensor devices to recognize other vehicles (preceding vehicles, following vehicles, vehicles traveling side by side, etc.) traveling in the surrounding area of ​​the vehicle. The cruise control device has a lane keeping assist (ALK; Active Lane Keeping) control function that causes the vehicle to travel along a target travel route set in the lane in which the vehicle is traveling, and a control function that causes the vehicle to travel according to a target vehicle speed value set in advance by the driver, and when a preceding vehicle is recognized, causes the vehicle to follow the preceding vehicle while maintaining the distance between the vehicle and the preceding vehicle, so-called adaptive cruise control with distance control function (ACC; Adaptive Cruise Control) function. Various types of cruise control devices have been proposed, for example, in JP 2009-184464 A, JP 2019-59360 A, etc., and are becoming generally practical.

[0004] The vehicle travel control device disclosed in the above-mentioned JP 2009-184464 A etc. performs control to set the upper limit set speed of the ACC function to the speed limit based on the vehicle speed of the host vehicle while traveling and the speed limit of the road on which the host vehicle is traveling, if the vehicle speed of the host vehicle is equal to or lower than the speed limit, and performs follow-up travel by controlling to set the upper limit set speed of the ACC function to the vehicle speed of the host vehicle, if the vehicle speed of the host vehicle exceeds the speed limit.

[0005] The vehicle driving control device disclosed in the above-mentioned Patent Publication No. 2019-59360 and the like performs following driving by appropriately setting the acceleration or deceleration when controlling the speed of the host vehicle to increase or decrease up to the speed limit, depending on the inter-vehicle distance and relative speed between the host vehicle and another vehicle (such as a preceding vehicle or a following vehicle). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2009-184464 A [Patent Document 2] JP 2019-59360 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the conventional vehicle cruise control devices disclosed in the above-mentioned JP 2009-184464 A and JP 2019-59360 A, the speed of the host vehicle is basically set appropriately according to the inter-vehicle distance and relative speed between the host vehicle and other vehicles traveling around the host vehicle. As a result, the behavior of the host vehicle (e.g., vehicle speed, acceleration / deceleration, etc.) changes depending on the behavior of the other vehicles.

[0008] Therefore, when the behavior of another vehicle tends to be unstable (for example, when the other vehicle does not maintain a constant speed or when the other vehicle accelerates and decelerates repeatedly), the behavior of the own vehicle may become unstable due to the behavior of the other vehicle. If the behavior of the own vehicle becomes unstable, for example, when unnatural acceleration and deceleration occur, there is a possibility that adverse effects such as a worsening of ride comfort and a decrease in fuel consumption rate may occur. In addition, if the own vehicle continues to travel while following another vehicle with unstable behavior, it may not be possible to ensure safe travel of the own vehicle.

[0009] The present invention aims to provide a vehicle driving control device that can provide a comfortable ride when controlling the vehicle's driving while taking into account other surrounding vehicles, while also contributing to improved fuel consumption and safe driving. [Means for solving the problem]

[0010] In order to achieve the above object, a vehicle driving control device according to one aspect of the present invention includes a surrounding environment information acquisition device that acquires surrounding environment information of a vehicle, a host vehicle status information acquisition device that acquires a host vehicle status, an external information receiving device that acquires at least road map information from an external device, a set vehicle speed value setting unit that sets a target vehicle speed value when performing driving control, and a driving control unit that controls the driving of the host vehicle by controlling the vehicle speed value of the host vehicle while taking into account other vehicles in the vicinity, based on a plurality of pieces of information acquired using the surrounding environment information acquisition device, the host vehicle status information acquisition device, and the external information receiving device. When it is confirmed that a preceding vehicle is recognized in front of the vehicle, the vehicle speed value of the vehicle exceeds the speed limit value of the road on which the vehicle is traveling or a predetermined speed value which is increased or decreased by a certain value based on the speed limit value, a driver set vehicle speed value set in advance by the driver is equal to or greater than the vehicle speed value of the preceding vehicle, and no following vehicle has been continuously recognized behind the vehicle for a predetermined period of time or more, the driving control unit sets a vehicle speed value which is a predetermined value lower than the vehicle speed value of the preceding vehicle as a temporary set vehicle speed value, and performs driving control using the temporary set vehicle speed value. Effect of the Invention

[0011] According to the present invention, it is possible to provide a vehicle driving control device that can provide a comfortable ride when controlling the vehicle's driving taking into account other surrounding vehicles, contribute to improving fuel consumption rate, and contribute to safe driving. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration of a driving control device according to an embodiment of the present invention; [Diagram 2] 1 is a flowchart (first half) showing a flow of processing of ACC control executed in a driving control device according to an embodiment of the present invention; [Diagram 3] 1 is a flowchart (middle part) showing a flow of processing of ACC control executed in a driving control device according to an embodiment of the present invention; [Figure 4] 1 is a flowchart (later part) showing a flow of processing of ACC control executed in a driving control device according to an embodiment of the present invention; [Diagram 5] FIG. 4 is a conceptual diagram for explaining the process sequence of step S11 in FIG. 2 to step S26 in FIG. 3 by using a specific example; [Figure 6] FIG. 5 is a conceptual diagram illustrating the process sequence of steps S27 to S29 in FIG. 4 using a specific example; [Figure 7] FIG. 5 is a conceptual diagram illustrating the process sequence of steps S30 to S32 in FIG. 4 using specific examples; [Figure 8] FIG. 5 is a conceptual diagram illustrating the process sequence of step S35 in FIG. 4 using a specific example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described below with reference to the illustrated embodiments. The drawings used in the following description are schematic, and the dimensional relationship and scale of each component may be different for each component in order to show each component at a size that can be recognized on the drawing. Therefore, the present invention is not limited to the illustrated form with respect to the quantity of each component, the shape of each component, the size ratio of each component, the relative positional relationship of each component, etc. shown in each drawing.

[0014] A driving control device according to an embodiment of the present invention is a device mounted on a vehicle such as an automobile, and performs driving control to assist the driver of the vehicle in driving the vehicle. The driving control device according to the present embodiment acquires information about the environment ahead of the vehicle and the surrounding environment (e.g., other vehicles such as a preceding vehicle, a following vehicle, an oncoming vehicle, a vehicle running alongside, bicycles, pedestrians, or other moving objects, buildings, various structures, three-dimensional obstacles, and information about the surrounding environment of the vehicle including the road surface conditions of the road on which the vehicle is traveling; hereinafter, simply referred to as surrounding environment information, etc.) using a sensing device such as an on-board camera unit or a radar device.

[0015] Furthermore, the driving control device of this embodiment recognizes road conditions, including information on preceding and following vehicles, various structures, three-dimensional obstacles, etc., based on road map information, etc. acquired from an external device such as a high-precision road map database through communication in addition to the surrounding environment information, etc. acquired as described above. The driving control device of this embodiment appropriately uses these various types of information (surrounding environment information, map information, recognition information, etc.) as information when executing driving control to assist the driver in driving operations.

[0016] The cruise control device of this embodiment has a configuration capable of executing at least active lane keeping (ALK) control and adaptive cruise control (ACC) with a vehicle distance control function.

[0017] Here, lane keeping assist control (hereinafter simply referred to as ALK control) is a control function that drives the vehicle along a target driving route set within the driving lane based on various information (surrounding environment information, etc.) acquired while the vehicle is driving, and continues to drive the vehicle safely while maintaining the driving lane.

[0018] In addition, cruise control with vehicle distance control function (hereinafter simply referred to as ACC control) is a control function that drives the vehicle according to a target vehicle speed value preset by the driver, and when a preceding vehicle is recognized, increases or decreases the vehicle speed of the vehicle taking into account the speed of the preceding vehicle, causing the vehicle to follow the preceding vehicle while maintaining the vehicle distance between the vehicle and the preceding vehicle.

[0019] The driving control device of this embodiment further has a function of controlling the driving of the vehicle, taking into account the positional relationship between the vehicle and these other vehicles, when the vehicle recognizes other vehicles (a preceding vehicle, a following vehicle, a vehicle traveling alongside, etc.) traveling near the vehicle while the vehicle is traveling on a road executing ALK control and ACC control.

[0020] In this case, the vehicle driving control that takes into account the positional relationship between the vehicle and other surrounding vehicles is slightly different from the normal ACC control (hereinafter referred to as normal ACC control) that causes the vehicle to follow the vehicle in front.

[0021] In short, for example, the driving control device of this embodiment performs ACC control to ensure that the vehicle can drive independently as much as possible by increasing the inter-vehicle distance (or relative distance) between the vehicle and other nearby vehicles, and to perform efficient driving that is not influenced by the behavior of other vehicles and at the same time, to realize driving that takes safety into consideration. In the following description, this type of driving control is referred to as "Eco ACC control."

[0022] The Eco ACC control executed in the driving control device of this embodiment automatically sets a provisional target vehicle speed value (provisional set vehicle speed value) at an appropriate predetermined timing to execute ACC control taking into consideration various information such as the speed limit of the road, the speed of the vehicle while driving, a target vehicle speed (driver set vehicle speed value; described in detail later) previously set by the driver in the vehicle, the speed of a preceding vehicle in the same lane as the vehicle, the presence of a following vehicle in the same lane as the vehicle and the vehicle speed of that following vehicle, the presence of a following vehicle or a vehicle running alongside in adjacent lanes on the left and right of the lane in which the vehicle is driving and the vehicle speeds of those following vehicles or vehicles running alongside, the behavior of the preceding vehicle, and the traffic congestion situation in the oncoming lane, and the like, and performs driving control of the vehicle using this provisional set vehicle speed value.

[0023] Then, when various conditions based on the surrounding circumstances and the like are met, the temporary set vehicle speed value is registered as a set vehicle speed value to be referenced when ACC control is executed in the ECO ACC control mode thereafter (hereinafter referred to as a registered set vehicle speed value).

[0024] First, a schematic configuration of a cruise control device according to one embodiment of the present invention will be described below with reference to Fig. 1. Fig. 1 is a block diagram showing a schematic configuration of a cruise control device according to one embodiment of the present invention.

[0025] The basic configuration of the travel control device of this embodiment is substantially similar to the configuration of the same type of travel control device in a conventional form. Therefore, when describing the configuration of the travel control device of this embodiment, only the main configuration related to the present invention will be described. The detailed configuration of the travel control device of this embodiment is substantially similar to that of a conventional travel control device, and detailed description of configurations other than those directly related to the present invention will be omitted. Also, in FIG. 1, only the main configuration of the travel control device of this embodiment is illustrated, and configurations not directly related to the present invention are omitted.

[0026] In the following description of the present embodiment, a road system based on left-hand traffic, in which vehicles are driven on the left side of the road, is used as an example. Therefore, the configuration of the present invention can be easily applied to a road system based on right-hand traffic by simply switching the left and right directions.

[0027] As shown in FIG. 1, the driving control device 1 of this embodiment has as its main components a locator unit 11, a periphery monitoring unit 20, a camera unit 21, a driving control unit 22 as a driving control section, an engine control unit 23, a power steering control unit 24, a brake control unit 25, etc.

[0028] Here, the locator unit 11, the surroundings monitoring unit 20, and the camera unit 21 are sensor units for recognizing the inside and outside of the vehicle and are constituent units that function as an environment recognition device. Each of these units (11, 20, 21) exists as a completely independent constituent unit without depending on each other.

[0029] Each control unit, namely, the driving control unit 22, the engine control unit 23, the power steering control unit 24, and the brake control unit 25, together with the locator unit 11, the surrounding monitoring unit 20, and the camera unit 21, are connected to each other via an in-vehicle communication line 10 such as a CAN (Controller Area Network), and share data as needed and appropriate.

[0030] Locator unit 11 is an information acquisition device that estimates the position of the vehicle (vehicle position) on a road map and acquires road map information, etc., mainly of the area ahead of the estimated vehicle position.

[0031] The locator unit 11 includes a map locator calculation unit 12, an acceleration sensor 13, a wheel speed sensor 14, a gyro sensor 15, a GNSS receiver 16, a road information receiver 17, a high-precision road map database (DB; Data Base, abbreviated as road map DB in FIG. 1) 18 as a map information storage unit, and a route information input unit 19.

[0032] Among these, the acceleration sensor 13, the wheel speed sensor 14, and the gyro sensor 15 are various sensors required for estimating the position of the host vehicle (host vehicle position). For example, the acceleration sensor 13 is a sensor that detects the longitudinal acceleration of the host vehicle. The wheel speed sensor 14 is a sensor that detects the rotational speed of each of the front, rear, left and right wheels (in the case of a four-wheeled vehicle). The vehicle speed of the host vehicle can be detected based on the detection results of the wheel speed sensor 14. The gyro sensor 15 is a sensor that detects the angular velocity or angular acceleration of the host vehicle. Each of these sensors (13, 14, 15) is an autonomous driving sensor group that functions as a driving state acquisition unit, and is connected to the input side of the map locator calculation unit 12.

[0033] The autonomous driving sensor group (sensors 13, 14, 15) are provided to enable autonomous driving when, for example, the reception sensitivity from a GNSS satellite (not shown) received by a GNSS receiver 16 (described in detail later) decreases and the positioning signal cannot be effectively received, for example, when driving inside a tunnel. In addition to the above-mentioned sensors (13, 14, 15), the autonomous driving sensor group also includes, for example, a vehicle speed sensor and a yaw rate sensor, although not shown.

[0034] The GNSS receiver 16 functions as a vehicle position acquisition unit and is a receiving device that receives various information from, for example, a GNSS (Global Navigation Satellite System). That is, the GNSS receiver 16 receives positioning signals transmitted from a plurality of positioning satellites. The GNSS receiver 16 outputs the acquired positioning signals to the map locator calculation unit 12 of the locator unit 11. The map locator calculation unit 12 estimates the vehicle position (latitude, longitude) based on the positioning signals received by the GNSS receiver 16 from the plurality of positioning satellites. For this reason, the GNSS receiver 16 is connected to the input side of the map locator calculation unit 12.

[0035] Furthermore, the map locator calculation unit 12 is connected to a road information receiver 17, a high-precision road map database 18 as a storage device, a route information input unit 19, and the like.

[0036] Road information receiver 17 is an external information receiving device that receives and acquires various information, such as information necessary for automatic driving and map information, stored in a predetermined base station (not shown) or a cloud server (not shown) connected via the Internet. Road information receiver 17 outputs the acquired various information to map locator calculation section 12 of locator unit 11. Road information receiver 17 may be in the form of a road information transmitting / receiving device further equipped with a function of transmitting various information possessed by the vehicle to the base station or cloud server (not shown).

[0037] The map locator calculation unit 12 performs map matching of the vehicle position on a map based on map information received by the road information receiver 17, and constructs a target driving route connecting the input destination and the vehicle position. Furthermore, the map locator calculation unit 12 sets a target driving route for executing automatic driving up to several kilometers ahead of the vehicle on the constructed target driving route. Here, items to be set as the target driving route include various items such as the lane in which the vehicle will travel (for example, which lane to travel in when there are three lanes), lane changes to overtake a preceding vehicle, and the timing to start lane changes.

[0038] The high-precision road map database 18 is mainly composed of large-capacity storage media such as HDD (Hard Disk Drive) and SSD (Solid State Drive). Well-known high-precision road map information (local dynamic map) is stored in this high-precision road map database 18. Here, the high-precision road map information has the same layer structure as a global dynamic map provided in, for example, a cloud server (not shown), and forms a hierarchical structure in which additional map information necessary to support automated driving is superimposed on the lowest static information layer that serves as the base.

[0039] The additional map information includes static location information such as road type (general road, expressway, etc.), road shape, left and right dividing lines (e.g. center line, outer side line, lane boundary line, etc.), exits of expressways and bypass roads, etc., entrance / exit lengths (start and end positions) of branch lanes and merging lanes leading to junctions, service areas, parking areas, etc., as well as dynamic location information such as traffic congestion information, accidents, or traffic restrictions due to construction work.

[0040] Then, when a target driving route is set by the map locator calculation unit 12, this additional map information is continuously obtained from the global dynamic map and sequentially updated as peripheral information required for the vehicle to autonomously drive along the set target driving route.

[0041] In addition, the high-precision road map information also contains lane data required for autonomous driving, such as lane width data, lane center position coordinate data, lane travel azimuth data, speed limit information, etc. This lane data and other information is stored at intervals of several meters for each lane on the road map.

[0042] The route information input unit 19 is a terminal device operated by a person in the vehicle, such as a driver or a passenger. The route information input unit 19 can collect and input a series of information required for setting a target driving route in the map locator calculation unit 12, such as setting a destination and intermediate points (such as a service area to stop at on a highway).

[0043] Specifically, route information input unit 19 is an input unit of a car navigation system (for example, a touch panel of a monitor, etc.), a mobile terminal such as a smartphone, a personal computer, etc. Route information input unit 19 is connected to map locator calculation unit 12 by wire or wirelessly. As a result, when a driver or a passenger operates route information input unit 19 to input information of a destination or a stopover point (facility name, address, telephone number, etc.), the input information is read into map locator calculation unit 12. Map locator calculation unit 12 sets the position coordinates (latitude, longitude) of the destination and the stopover point input from route information input unit 19.

[0044] The map locator calculation unit 12 includes a vehicle position estimation unit 12a, a map information acquisition unit 12b, and the like.

[0045] The vehicle position estimation unit 12a is a component having a function of estimating the vehicle position. The vehicle position estimation unit 12a acquires the position coordinates (latitude, longitude) of the vehicle based on the positioning signal received by the GNSS receiver 16. Then, the vehicle position estimation unit 12a performs map matching of the acquired position coordinates on route map information to estimate the vehicle position (current position) on the road map.

[0046] In addition, in an environment where a valid positioning signal from a positioning satellite cannot be received due to reduced sensitivity of the GNSS receiver 16, such as when driving inside a tunnel, the vehicle position estimation unit 12a switches to autonomous navigation, which estimates the vehicle position based on various data such as vehicle speed data obtained based on the wheel speed detected by the wheel speed sensor 14, angular velocity data detected by the gyro sensor 15, and longitudinal acceleration data detected by the acceleration sensor 13, and estimates the vehicle position (latitude, longitude) on a road map.

[0047] The map information acquisition unit 12b constructs target driving route information from the current location to the destination (target driving route information connecting the vehicle's position on the high-precision road map information and the destination (or the destination via the via point if a via point is set)) based on the position information (latitude, longitude) of the vehicle's position estimated by the vehicle position estimation unit 12a and the position information (latitude, longitude) of the destination and the via point input by the driver or the like from the route information input unit 19, according to a route condition (recommended route, fastest route, etc.) set in advance. At this time, the vehicle position estimation unit 12a identifies the driving lane in which the vehicle is traveling, acquires road shapes such as driving lanes and merging lanes stored in the road map data, and sequentially stores this information. The map information acquisition unit 12b also transmits the target driving route information to the vehicle position estimation unit 12a.

[0048] In this way, the map locator calculation unit 12 performs map matching of the vehicle position estimated by the vehicle position estimation unit 12a on a road map to identify the current location of the vehicle, and acquires road map information including information on the surrounding conditions. In addition, the map information acquisition unit 12b sets a target driving route as a target for the vehicle.

[0049] The camera unit 21 is a surrounding environment information acquisition device that recognizes the environment mainly in the traveling direction (forward) of the vehicle and acquires it as image information, and constitutes a part of the surrounding environment recognition device.

[0050] Specifically, the camera unit 21 recognizes various road surroundings, including, for example, other vehicles traveling in front of and to the sides of the vehicle (both preceding vehicles, oncoming vehicles, vehicles traveling alongside, etc.), three-dimensional objects including moving objects such as bicycles and motorcycles traveling alongside, road markings such as traffic lights (light color, flashing state, arrow direction, etc.), road signs, stop lines and dividing lines (e.g., center line of the road, outer side line of the road, lane boundary line, etc.), and road surface conditions (e.g., the presence, shape, size, etc. of puddles on the road surface).

[0051] The camera unit 21 is fixed to the upper center of the front part of the passenger compartment of the vehicle and is configured to include an on-board camera (stereo camera) consisting of a main camera 21a and a sub-camera 21b arranged at symmetrical positions on either side of the center of the vehicle width, an image processing unit (IPU) 21c, a driving environment recognition unit 21d, etc.

[0052] The camera unit 21 captures reference image data with the main camera 21a, which is an image capture device, and captures comparison image data with the sub-camera 21b, which is also an image capture device. The two image data captured by these two cameras (21a, 21b) are subjected to predetermined image processing by the IPU 21c.

[0053] The driving environment recognition unit 21d reads the reference image data and comparison image data that have been image-processed by the IPU 21c, recognizes the same object in both images based on the parallax between the two images, and calculates distance data (distance information from the vehicle to the object) from the positional deviation amount of the object in both images using the principle of triangulation, and generates forward driving environment image information (distance image information) that includes this distance information.

[0054] Further, the driving environment recognition unit 21d recognizes various road markings including, for example, dividing lines (e.g., a center line, an outer side line, a lane boundary line, etc.) dividing the left and right of the driving lane in which the vehicle is traveling as surrounding environment information based on distance image information acquired by the camera unit 21 and processed by the IPU 21c. In this case, the driving environment recognition unit 21d functions as a dividing line detection unit that detects dividing lines of the driving lane.

[0055] The driving environment recognition unit 21d also obtains the road curvature [1 / m] at the center of the left and right dividing lines (lane boundary lines, etc.) of the road on which the host vehicle is traveling (host vehicle driving lane), the width between the left and right dividing lines (lane width), and the like.

[0056] There are various known methods for determining the road curvature and lane width at the center between lane lines, but for example, the driving environment recognition unit 21d recognizes the left and right lane lines by binarization processing based on the brightness difference based on the forward driving environment image information, determines the curvature of the left and right lane lines for each predetermined section by a curve approximation formula using the least squares method, and calculates the lane width from the difference in curvature between the two lane lines.The driving environment recognition unit 21d then determines the road curvature at the center of the lane based on the curvature of the left and right lane lines of the own lane and the lane width.

[0057] Furthermore, the driving environment recognition unit 21d performs predetermined pattern matching on the distance image information to recognize guardrails, curbs, and various three-dimensional objects (pedestrians, motorcycles, vehicles other than motorcycles, and the like that are present around the vehicle) that exist along the road. Here, when the driving environment recognition unit 21d recognizes three-dimensional objects, for example, the type of the three-dimensional object, the distance to the three-dimensional object, the moving speed of the three-dimensional object, and the relative speed between the three-dimensional object and the vehicle are recognized.

[0058] In addition to the above-mentioned two cameras (21a, 21b), the camera unit 21 may further include a camera (rear camera, not shown) as an image acquisition device for recognizing other vehicles (following vehicles, etc.) traveling behind the vehicle. This rear camera is installed facing the rear of the vehicle and mainly acquires rear images of the vehicle. If the camera unit 21 is configured in this way, it can be configured so that the two cameras (21a, 21b) can recognize other vehicles traveling mainly in front and on the front sides of the vehicle, and the rear camera can recognize other vehicles traveling mainly behind and on the rear sides of the vehicle.

[0059] The surroundings monitoring unit 20 is a surrounding environment information acquisition device that recognizes the surroundings of the vehicle and acquires the information, and constitutes a part of the surroundings situation recognition device. The surroundings monitoring unit 20 is configured with a surrounding environment recognition sensor 20a, a surrounding environment recognition unit 20b, etc.

[0060] The surrounding environment recognition sensor 20a is a group of autonomous sensors serving as surrounding environment detection means, which includes sensing devices such as an ultrasonic sensor, a millimeter wave radar, a LIDAR (Light Detection and Ranging), a camera, and a combination of these.

[0061] Specifically, for example, a plurality of millimeter wave radars serving as the surrounding environment recognition sensor 20a are disposed at the four corners of the vehicle (for example, the left front side, the right front side, the left rear side, the right rear side, etc.). Of these, the left and right front side millimeter wave radars are provided, for example, at the left and right sides of the front bumper, and are used to monitor some areas around the vehicle that are difficult to recognize using images acquired by the two cameras 21a, 21b of the camera unit 21 (areas diagonally forward and to the left and right of the vehicle).

[0062] In addition, the left and right rear side millimeter wave radars are provided, for example, on the left and right sides of the rear bumper and are used to monitor some areas around the vehicle (areas from the sides to the rear of the vehicle) that cannot be monitored by the left and right front side millimeter wave radars.

[0063] The surrounding environment recognition unit 20b acquires surrounding environment information, which is information about moving objects (for example, a vehicle traveling alongside, a following vehicle, an oncoming vehicle, etc.) around the host vehicle, based on an output signal from the surrounding environment recognition sensor 20a.

[0064] The periphery monitoring unit 20 and the camera unit 21 constitute a surrounding environment information acquisition device and a surrounding situation recognition device in the driving control device 1 of this embodiment. Here, the driving environment recognition section 21d of the camera unit 21 and the surrounding environment recognition section 20b of the periphery monitoring unit 20 are connected to the input side of the driving control unit 22 through the in-vehicle communication line 10. In addition, the driving control unit 22 and the map locator calculation section 12 are connected to each other via the in-vehicle communication line 10 so as to be able to communicate freely in both directions.

[0065] Connected to the input side of the driving control unit 22 are a mode change switch 33, a steering wheel touch sensor 34, a steering torque sensor 35, a brake sensor 36, an accelerator sensor 37, etc., as a plurality of various switches or a group of sensors that detect the vehicle's internal environment information (vehicle status information).

[0066] The mode changeover switch 33 refers to a group of switches that the driver switches on and off to select various driving modes and multiple control functions related to driving assistance control. By operating the mode changeover switch 33, the driver can arbitrarily and selectively switch on and off a desired driving control among various driving controls that can be executed by the driving control device 1 of this embodiment, such as switching a desired driving assistance control mode or switching each control mode of the ACC control described later (e.g., normal ACC control mode, eco ACC control mode, etc.), as appropriate and at a desired time.

[0067] Furthermore, the mode changeover switch 33 includes, for example, an input operation member for the driver of the vehicle to preset a target vehicle speed value (set vehicle speed value) to be referenced when executing ACC control. Note that the target vehicle speed value (set vehicle speed value) that is actively input and set by the driver using this input operation member will be referred to as a driver set vehicle speed value in the following description.

[0068] The steering wheel touch sensor 34 is a sensor for detecting a state in which the driver is gripping a steering wheel (not shown; hereinafter simply referred to as steering wheel) in a steering device, that is, a state in which the driver is holding the steering wheel. The steering wheel touch sensor 34 is provided at a predetermined position on the steering wheel of the vehicle. The steering wheel touch sensor 34 outputs an ON signal when the driver is gripping a predetermined portion of the steering wheel (when the driver is in a holding steering state).

[0069] The steering torque sensor 35 is a sensor that detects steering torque as an amount of driving operation by a driver, and is provided on a steering shaft (not shown) in a steering device of the vehicle.

[0070] The steering wheel touch sensor 34 and the steering torque sensor 35 are sensors for recognizing the state of the steering wheel maintained by the driver of the vehicle and function as a steering state recognition unit. The output signals of both of these sensors (34, 35) are output to the cruise control unit 22.

[0071] The brake sensor 36 is a sensor that detects the amount of depression of the brake pedal as an amount of driving operation by the driver.

[0072] The accelerator sensor 37 is a sensor that detects the amount of depression of the accelerator pedal as an amount of driving operation by the driver.

[0073] Meanwhile, an alarm device 38 equipped with a monitor panel, a speaker, etc. is connected to the output side of the driving control unit 22. The alarm device 38 is a device that notifies the driver of the surrounding environment information acquired by the driving control unit 22 by the driving environment recognition unit 21d, the surrounding environment recognition unit 20b, etc., and an alarm corresponding to the surrounding environment recognized based on the surrounding environment information (for example, a visual alarm display on a display device such as a monitor panel, an auditory alarm display by a sound device such as a speaker, a horn, etc.).

[0074] In addition, the notification device 38 displays various types of indications to the driver as necessary, such as indications suggesting the operation the driver should perform (specifically, indications such as "Please press the brake pedal," "Please release the accelerator," "Please correct the steering wheel," etc.), which the driver can perceive audibly or visually.

[0075] The cruise control unit 22 is a component unit that performs overall control of the cruise of the vehicle. For example, the cruise control unit 22 contributes to cruise control when performing ALK control, ACC control, and the like.

[0076] In this case, the driving control unit 22 in the driving control device 1 of this embodiment functions as a driving control unit that automatically changes the set vehicle speed value for ACC control in accordance with the surrounding vehicles, surrounding conditions, vehicle conditions, etc. recognized by the driving vehicle while executing ALK control and ACC control, and performs driving control based on the changed set vehicle speed value.

[0077] For this purpose, the driving control unit 22 is configured to include a steering assistance control section 22a, a target driving route setting section 22b, a set vehicle speed value setting section 22c, and the like.

[0078] The steering assist control unit 22a performs control to assist driving control involving steering operations among the various controls that can be executed by the driving control device 1 of this embodiment, such as steering operations to stably drive the vehicle within the driving lane, and assisting steering operations performed by the driver when avoiding collisions or contact with dangers, etc. that the vehicle may encounter while driving or obstacles, etc. on the driving path.

[0079] For example, the steering assist control unit 22a performs steering assist control as needed during execution of ALK control for driving the vehicle along a set target driving route.

[0080] The target driving route setting unit 22b sets the center position of the driving lane as the target driving route based on lane width data, etc., based on information regarding the left and right dividing lines of the vehicle's driving lane (host vehicle driving lane) obtained based on the surrounding environment information recognized by the driving environment recognition unit 21d of the camera unit 21.

[0081] Then, the target driving route setting unit 22b recognizes an area including the set target driving route as the driving lane in which the host vehicle will travel. The target driving route drawn in the center position of the recognized driving lane is set within the host lane, and becomes a virtual driving line that is a target when the host vehicle travels by executing ALK control.

[0082] The set vehicle speed value setting unit 22c is a component that sets a vehicle speed value that is used as a guide for driving when ACC control is executed. This set vehicle speed value setting unit 22c is composed of, for example, a circuit unit or the like provided in the driving control unit 22. The set vehicle speed value setting unit 22c sets, for example, a driver set vehicle speed value that is set by the driver of the vehicle or the like prior to executing ACC control, a registered set vehicle speed value that is referred to during ACC control, and a temporary set vehicle speed value that is automatically set during driving control in the eco ACC control mode.

[0083] The driver set vehicle speed value is a target vehicle speed value input by the driver operating, for example, an input operation member (not shown) included in the mode changeover switch 33. This driver set vehicle speed value is stored, for example, in a predetermined internal storage area (internal memory; not shown) in the cruise control unit 22.

[0084] The temporary set vehicle speed value is a set vehicle speed value that is temporarily set by increasing or decreasing the registered set vehicle speed value based on the vehicle status, surrounding vehicles, surrounding conditions, etc., and predetermined conditions during driving control in the ECO ACC control mode. The temporary set vehicle speed value is a setting value that is temporarily used during ACC control.

[0085] The registered set vehicle speed value is a vehicle speed value that is referred to when the ACC control is continuously executed and registered as a guide for driving. The set vehicle speed value setting unit 22c, for example, registers the driver set vehicle speed value as the registered set vehicle speed value used in driving control during the ACC control. The set vehicle speed value setting unit 22c also registers, for example, a temporary set vehicle speed value that is appropriately set during driving control in the ECO ACC control mode as a new registered set vehicle speed value at a predetermined timing in consideration of the vehicle situation, surrounding other vehicles, surrounding conditions, etc.

[0086] In addition, the driving control unit 22 performs various predetermined situation judgments, etc. based on output information from the camera unit 21 (the driving environment recognition unit 21d) and the periphery monitoring unit 20 (the surrounding environment recognition unit 20b), as well as various information obtained through the map locator calculation unit 12, and also based on vehicle internal environment information (host vehicle status information) acquired by host vehicle status information acquisition devices such as the mode change switch 33 and various sensors (34, 35, 36, 37), and performs driving control of the host vehicle through the engine control unit 23, power steering control unit 24, brake control unit 25, etc. based on these judgment results.

[0087] When an automatic driving section where automatic driving control is permitted is set within the target driving route set by the map locator calculation unit 12, the driving control unit 22 sets a driving route for performing automatic driving control in the automatic driving section. In the automatic driving section, the driving control unit 22 has a function of appropriately controlling the engine control unit 23, the power steering control unit 24, the brake control unit 25, etc. to automatically drive the vehicle along the target driving route set from the vehicle position estimated based on various information.

[0088] At that time, the driving control unit 22 performs driving control that takes into consideration other surrounding vehicles, such as making the vehicle follow the preceding vehicle according to the control mode of the ACC control that is appropriately selected and set, based on the surrounding environment information recognized by the driving environment recognition unit 21d, for example, by ALK control and ACC control, if a preceding vehicle is recognized. Also, at this time, if a preceding vehicle is not recognized, the driving control unit 22 performs driving control of the host vehicle according to the driver set vehicle speed value or the registered set vehicle speed value. At the same time, in addition to the ALK control, various driving controls are performed, such as steering assistance control that is appropriately selected, such as lane departure suppression control and lane change control, and further, in some cases, driver abnormality response control.

[0089] As described above, the cruise control unit 22 is connected to each of the control units, such as the engine control unit 23, the power steering control unit 24, and the brake control unit 25, through the in-vehicle communication line 10. In this way, the cruise control unit 22 controls each of the control units (23, 24, 25) and the like.

[0090] A throttle actuator 27 is connected to the output side of the engine control unit 23. This throttle actuator 27 opens and closes a throttle valve of an electronically controlled throttle provided on a throttle body of the engine. The cruise control unit 22 controls the throttle actuator 27 with a drive signal from the engine control unit 23 to open and close the throttle valve and adjust the intake air flow rate. This makes it possible to generate a desired engine output.

[0091] An electric power steering motor 28 is connected to the output side of the power steering control unit 24. This electric power steering motor 28 applies steering torque to the steering mechanism by the rotational force of the electric motor. When a predetermined driving mode is selected, the cruise control unit 22 controls the electric power steering motor 28 by a drive signal from the power steering control unit 24, thereby executing various steering assist controls that assist steering operations. In addition, a steering torque sensor 35 presents a steering torque value by detecting a change in the drive amount of the electric power steering motor 28 or the drive amount of the steering mechanism.

[0092] A brake actuator 29 is connected to the output side of the brake control unit 25. This brake actuator 29 adjusts the brake hydraulic pressure supplied to the brake wheel cylinders provided on each wheel. The travel control unit 22 drives the brake actuator 29 by a drive signal from the brake control unit 25. As a result, the brake wheel cylinders generate braking force on each wheel, forcibly decelerating the vehicle.

[0093] In addition, all or some of the map locator calculation unit 12, the surrounding environment recognition unit 20b, the driving environment recognition unit 21d, the driving control unit 22, the engine control unit 23, the power steering control unit 24, the brake control unit 25, etc. are configured by a processor including hardware.

[0094] Here, the processor is configured by a well-known configuration including, for example, a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), a non-volatile memory, a non-volatile storage device, a non-transitory computer readable medium, and peripheral devices.

[0095] Software programs executed by the CPU and fixed data such as data tables are stored in advance in ROM, non-volatile memory, non-volatile storage device, etc. Then, the CPU reads out the software programs stored in ROM, etc., expands them in RAM, and executes them, and the software programs appropriately refer to various data, etc., thereby realizing the functions of the above-mentioned components and components (12, 20b, 21d, 22, 23, 24, 25), etc.

[0096] The processor may be configured with a semiconductor chip such as a Field Programmable Gate Array (FPGA), etc. Furthermore, the above-mentioned components and components units (12, 20b, 21d, 22, 23, 24, 25) may be configured with electronic circuits.

[0097] Furthermore, the software program may be in a form in which the whole or part of the software program is recorded as a computer program product on a portable disk medium such as a flexible disk, CD-ROM, or DVD-ROM, or on a non-transitory computer readable medium such as a card-type memory, HDD (Hard Disk Drive) device, or SSD (Solid State Drive) device.

[0098] The operation of a vehicle equipped with the cruise control device 1 of one embodiment of the present invention configured as described above when the vehicle runs on a road while executing ACC control will be described below. Figures 2 to 4 are flowcharts showing the flow of processing for ACC control executed in the cruise control device of this embodiment. Note that Figure 2 shows the first half of the flowchart for ACC control, Figure 3 shows the middle half of the flowchart for ACC control, and Figure 4 shows the latter half of the flowchart for ACC control.

[0099] When the driver starts the vehicle equipped with the driving control device 1 of this embodiment, the operation of each component unit such as the camera unit 21, the surrounding monitoring unit 20, the driving control unit 22, etc. is initiated, and the vehicle starts driving on the road when the driver performs a specified operation.

[0100] Here, after starting the vehicle and before the vehicle starts to travel, the driver appropriately operates various operating members, such as those included in the mode changeover switch 33, to select the desired driving control. Note that the driving control related to the present invention mainly relates to ACC control. Therefore, the driver first turns on the ACC control and selects the control mode in the ACC control. In addition, the driver inputs a driver set vehicle speed value, which is a guideline for driving control during ACC control, using a predetermined operating member, and sets it in the driving control device 1. Setting value information such as the driver set vehicle speed value set here is stored, for example, in an internal memory (not shown) of the driving control unit 22.

[0101] When these operations are performed, the driving control device 1 starts ACC control in the selected and set control mode (normal ACC control mode, eco ACC control mode, etc.) Then, when the driver performs a predetermined driving operation, the vehicle starts traveling on the road.

[0102] In the following description, for the sake of simplicity, only matters directly related to the present invention (ACC control) will be mentioned, and explanations of operations, actions, controls, etc. related to matters unrelated to the present invention will be omitted.

[0103] First, in step S11 of Fig. 2, the cruise control unit 22 checks whether the currently set control mode of the ACC control is "Eco ACC control mode". If the control mode is set to Eco ACC control mode, the process proceeds to the next step S12, where a processing sequence corresponding to the Eco ACC control mode is started. On the other hand, if the control mode is set to a mode other than Eco ACC control mode, the process proceeds to step S41.

[0104] In step S41, the cruise control unit 22 starts a processing sequence corresponding to the normal ACC control mode. This normal ACC control mode is basically a control in which the vehicle is driven at a driver set vehicle speed value preset by the driver. Then, when a preceding vehicle is recognized during the driving control, the host vehicle is controlled to follow the preceding vehicle while maintaining the distance between the host vehicle and the preceding vehicle. Such a driving control corresponding to the normal ACC control mode is a well-known control performed by a conventional driving control device. Therefore, further explanation is omitted.

[0105] The control process of the normal ACC control mode executed in the process of step S41 described above ends (returns) when, for example, the driver switches between modes or the vehicle is stopped (engine off).

[0106] In the driving control device 1 of this embodiment, only the "normal ACC control mode" is illustrated as a control mode other than the Eco ACC control mode, but other control modes may exist. However, when explaining the driving control device 1 of this embodiment, the control modes related to ACC control other than the Eco ACC control mode are not directly related to the present invention, so their explanation will be omitted. Next, the details of the processing sequence corresponding to the Eco ACC control mode in the driving control device 1 of this embodiment will be explained.

[0107] In the process of step S11 described above, when it is confirmed that the ECO ACC control mode is set and the process proceeds to the process of step S12 in Fig. 2, in this step S12, the driving control unit 22 starts the surrounding environment recognition process of the host vehicle and the host vehicle situation recognition process of the host vehicle itself through the surrounding environment recognition unit 20b, the driving environment recognition unit 21d, etc., as well as the locator unit 11, etc. Then, the process proceeds to step S13.

[0108] The surrounding environment recognition process for the vehicle performed here is a process for recognizing the environment in front of and around the vehicle, including information such as left and right dividing lines of the lane in which the vehicle is traveling and adjacent lanes, road signs (speed limit signs, etc.), and information on other vehicles in the vicinity.

[0109] The host vehicle's own vehicle status recognition process is a process for recognizing various information such as the current vehicle speed value of the host vehicle, the type of cruise control that has been set, the set driver set vehicle speed value or the registered set vehicle speed value, etc. The surrounding environment recognition process and the host vehicle status recognition process performed here are continuously performed while the cruise control device 1 is running.

[0110] At this point in time, it is assumed that at least information regarding the speed limit of the road on which the vehicle is traveling has been acquired. This information regarding the speed limit can be acquired, for example, from road signs or road markings that can be recognized based on image data acquired by camera unit 21. Furthermore, the information regarding the speed limit may be included in map information acquired by locator unit 11. At this point in time, it is assumed that at least information regarding the vehicle's status, such as the speed value information of the vehicle and the set driver set vehicle speed value or registered set vehicle speed value, has been acquired.

[0111] Next, in step S13, the cruise control unit 22 checks whether or not the preceding vehicle has been recognized. If the preceding vehicle has not been recognized, the process returns to step S12. If the preceding vehicle has not been recognized, the cruise control is performed in the same manner as the normal ACC control, in which the vehicle speed is maintained while the host vehicle is traveling, using the currently set registered set vehicle speed value (driver set vehicle speed value or a temporary set vehicle speed value automatically set by a control process described later, etc.) as a guide. Then, the process returns to step S12.

[0112] On the other hand, if a preceding vehicle is recognized in the process of step S13 described above, the process proceeds to the next step S14.

[0113] Next, in step S14, the cruise control unit 22 checks whether the vehicle speed of the host vehicle recognized in the process of step S12 described above exceeds the speed limit of the road on which the host vehicle is traveling (host vehicle speed>road speed limit). The vehicle speed of the host vehicle is calculated in the cruise control unit 22, for example, based on the wheel speed calculated based on data detected by the wheel speed sensor 14 or the like, and then based on the calculated wheel speed data and the host vehicle's wheel data (numerical information such as tire diameter, etc.). A well-known technique is used for this vehicle speed calculation technique.

[0114] In the process of step S14, if the speed of the host vehicle is equal to or lower than the speed limit of the road on which the host vehicle is traveling, the process returns to step S12. At this time, the host vehicle is considered to be traveling at a speed value equal to or lower than the speed limit and following the preceding vehicle. Such a traveling situation of the host vehicle can generally be judged to be a state in which the host vehicle continues to travel safely. Therefore, when it is judged that the host vehicle is in such a situation, control is performed to make the host vehicle follow the preceding vehicle while maintaining a predetermined distance between the host vehicle and the preceding vehicle, as in the normal ACC control. Then, the process returns to step S12.

[0115] On the other hand, if the speed of the vehicle exceeds the speed limit of the road on which the vehicle is traveling in the process of step S14, the process proceeds to the next step S15. If the speed of the vehicle exceeds the speed limit at this time, it can be assumed that the driver set speed value is also set to a speed value that exceeds the speed limit.

[0116] In the next step S15, the cruise control unit 22 checks whether the currently set registered set vehicle speed value (driver set vehicle speed value or automatically set temporary set vehicle speed value) is equal to or greater than the vehicle speed of the preceding vehicle. Here, the vehicle speed of the preceding vehicle can be calculated by a known technique based on the result of stereo image recognition by the camera unit 21, for example.

[0117] In the process of step S15, if the current registered set vehicle speed value is less than the vehicle speed of the preceding vehicle, the process returns to the process of step S12. Here, when the current registered set vehicle speed value is less than the vehicle speed of the preceding vehicle, the host vehicle is not controlled to travel at a speed equal to or greater than the registered set vehicle speed. Therefore, if the host vehicle continues to perform the travel control to maintain the vehicle speed based on the current registered set vehicle speed value at this time, the vehicle distance between the host vehicle and the preceding vehicle will gradually increase because the vehicle speed of the preceding vehicle is faster than the host vehicle. This means that the host vehicle is not affected by the preceding vehicle. Therefore, in a situation where the current registered set vehicle speed value is less than the vehicle speed of the preceding vehicle, the host vehicle performs the control to continue traveling to maintain the vehicle speed based on the current registered set vehicle speed value. Then, the process returns to the process of step S12.

[0118] On the other hand, if the current registered set vehicle speed value is equal to or higher than the vehicle speed of the preceding vehicle in the process of step S15 described above, the process proceeds to the next step S16. Here, when the current registered set vehicle speed value is equal to or higher than the vehicle speed of the preceding vehicle, the host vehicle is approaching the preceding vehicle, and there is a possibility that the host vehicle will catch up with the preceding vehicle in the future. In addition, as described above, it is known that the host vehicle is traveling at a speed exceeding the speed limit at this time (see step S14). Therefore, under such circumstances, it cannot be said that the host vehicle is in a state where safe traveling is ensured, and the host vehicle is traveling at a high speed that is higher than the vehicle speed of the surrounding other vehicles, particularly the preceding vehicle, and there is a concern of a decrease in the fuel consumption rate.

[0119] Therefore, in the driving control device 1 of this embodiment, when such a situation is confirmed, in the processing from step S17 described below, driving control is appropriately performed at a vehicle speed value lower than the vehicle speed of the preceding vehicle (described in detail later).

[0120] However, at this time, there is a possibility that a following vehicle is following the own vehicle on the same lane (hereinafter referred to as the own lane) in which the own vehicle is traveling, or that the following vehicle is approaching the own vehicle from the rear on the own lane. In such a situation, if the own vehicle performs deceleration control so as to change from its current vehicle speed value to a vehicle speed value lower than the vehicle speed of the leading vehicle, there is a possibility that the smooth traveling of the following vehicle behind the own vehicle will be disturbed or impeded.

[0121] Taking this into consideration, in the cruise control device 1 of this embodiment, first, after the processing of step S15 described above, in the next step S16, the presence of a following vehicle traveling behind the own vehicle on the own vehicle lane is confirmed.

[0122] That is, in step S16, the cruise control unit 22 checks whether a following vehicle in the own lane has been continuously detected for a predetermined time or more. Here, a situation in which a following vehicle has been continuously detected for a predetermined time or more may be a case in which a following vehicle following the own vehicle is traveling behind the own vehicle on the own lane, or a following vehicle is approaching the own vehicle from behind on the own lane, etc.

[0123] Therefore, when it is confirmed in the process of step S16 that a following vehicle has been continuously detected in the own lane for a predetermined period of time or more, the process returns to the process of step S12, taking into consideration the following vehicle. In this way, the ACC control in the ECO ACC control mode is not started when a following vehicle is present.

[0124] On the other hand, if it is confirmed in the processing of step S16 that a following vehicle has not been detected in the own lane continuously for a predetermined period of time or more, the processing proceeds to the next step S17, and ACC control in the ECO ACC control mode is started.

[0125] First, in step S17, the cruise control unit 22 sets a predetermined speed value lower than the vehicle speed of the preceding vehicle as a provisional set vehicle speed value (hereinafter referred to as provisional set vehicle speed value). Here, the provisional set vehicle speed value to be set is a vehicle speed value lower than the currently recognized vehicle speed of the preceding vehicle, for example, a speed value temporarily subtracting 10% from the vehicle speed value of the preceding vehicle.

[0126] Next, in step S18, the driving control unit 22 checks whether the temporary set vehicle speed value set in the processing of step S17 described above is less than a predetermined speed value based on the speed limit of the road on which the vehicle is currently traveling (hereinafter referred to as the predetermined value based on the speed limit).

[0127] Here, the predetermined value of the speed limit standard refers to a predetermined speed value that is defined based on the speed limit of the road on which the vehicle is currently traveling. Specifically, the predetermined value of the speed limit standard is set, for example, to a speed value equal to the speed limit of the road on which the vehicle is currently traveling, or a speed value obtained by subtracting 10 to 50 percent of the speed limit.

[0128] For example, if the predetermined value of the speed limit standard is set to a speed value that is 20% less than the speed limit, then when the speed limit of the road on which the vehicle is traveling is 80km / h, the predetermined value of the speed limit standard is set to 64km / h. Also, when the speed limit of the road on which the vehicle is traveling is 100km / h, the predetermined value of the speed limit standard is set to 80km / h.

[0129] Here, when determining the specified value of the speed limit standard, the amount by which to subtract from the speed limit can be set appropriately taking into consideration various conditions such as the individual driving control device 1, the type of vehicle in which the driving control device 1 is installed, and the road conditions during driving (whether the road is a highway or a general road, etc.).

[0130] The predetermined value of the speed limit standard may be set to a speed value equal to the speed limit of the road on which the vehicle is traveling. However, it is preferable that a set value exceeding the speed limit of the road on which the vehicle is traveling is not set. In other words, it is preferable that the predetermined value of the speed limit standard is set to be equal to or less than the speed limit. Although details will be described later, the predetermined value of the speed limit standard is specified as a lower limit value of the temporary set vehicle speed value that is automatically set when ACC control is performed in the eco ACC control mode. By setting the predetermined value of the speed limit standard in this way, the vehicle control device 1 can suppress the vehicle speed of the vehicle to within the speed limit and can control the vehicle to travel away from the preceding vehicle, as will be described later. Therefore, the vehicle control device 1 of this embodiment can maintain smooth and safe driving control.

[0131] In the process of step S18, if the temporarily set vehicle speed value set in the process of step S17 described above is less than the predetermined value of the speed limit reference, the process proceeds to step S19.

[0132] Next, in step S19, the cruise control unit 22 sets the predetermined value of the road speed limit standard as a new temporary set vehicle speed value, and then proceeds to the process of step S20 in Fig. 3 (see circled number (3) in Figs. 2 and 3).

[0133] On the other hand, in the processing of step S18 described above, if the temporary set vehicle speed value set in the processing of step S17 described above exceeds the predetermined value of the speed limit standard, the processing proceeds to step S20 in Figure 3 (see circled number (3) in Figures 2 and 3).

[0134] The process of steps S18 to S19 will be described in further detail. The temporarily set vehicle speed value set at the time of step S18 is a vehicle speed value lower than the vehicle speed of the preceding vehicle (step S17). In addition, as described above, the predetermined value of the speed limit reference is a predetermined value whose upper limit value is a speed value equal to the speed limit.

[0135] Therefore, in the processing of step S18 described above, if the temporary set vehicle speed value (= a vehicle speed value lower than the vehicle speed of the preceding vehicle) is less than a predetermined value of the speed limit standard (the upper limit value is the speed limit value), even if the vehicle travels at a speed that is the predetermined value of the speed limit standard that exceeds the current temporary set vehicle speed value, the vehicle speed value lower than the vehicle speed value of the preceding vehicle is maintained, and there is no possibility of the vehicle catching up with the preceding vehicle.

[0136] This is because, at this point in time, it is assumed that the preceding vehicle is traveling at a speed exceeding the speed limit. If the speed of the preceding vehicle is equivalent to the speed limit, the temporary set vehicle speed value set in the process of step S17 is a vehicle speed value lower than the vehicle speed of the preceding vehicle, so the temporary set vehicle speed value is equal to or lower than the speed limit. Also, if the preceding vehicle is traveling at a speed exceeding the speed limit, the temporary set vehicle speed value set in the process of step S17 is a vehicle speed value lower than the vehicle speed of the preceding vehicle, so the temporary set vehicle speed value is a vehicle speed value slightly higher than the speed limit or equal to or lower than the speed limit.

[0137] In such a situation, the temporarily set vehicle speed value is increased to a predetermined value based on the speed limit in the process of step S19. In this case, the temporarily set vehicle speed value does not exceed the speed limit, so the vehicle does not catch up with the preceding vehicle and can maintain safe driving.

[0138] On the other hand, if the temporarily set vehicle speed value (= a vehicle speed value lower than the vehicle speed of the preceding vehicle) exceeds the predetermined value of the speed limit standard (the upper limit value is the speed limit value) in the process of step S18 described above, the host vehicle has no possibility of catching up with the preceding vehicle if the current temporarily set vehicle speed value (= a vehicle speed value lower than the vehicle speed of the preceding vehicle) is maintained. Therefore, in this case, the process proceeds to step S20 without going through the process of step S19 and while maintaining the current temporarily set vehicle speed value.

[0139] Next, in step S20 of FIG. 3, the cruise control unit 22 checks whether or not the driver has performed a change operation of the driver set vehicle speed value after the processing of step S15 described above. Here, the following situations are considered as situations in which the driver may perform a change operation of the driver set vehicle speed value. As described above, at a predetermined time point after the processing of step S15, the driver of the host vehicle may recognize that the host vehicle is approaching the preceding vehicle. In such a case, the driver of the host vehicle may arbitrarily change the setting to a lower driver set vehicle speed value. Therefore, in the cruise control device 1 of this embodiment, in the processing of step S20, it is checked whether or not the driver set vehicle speed value has been changed.

[0140] If it is confirmed in the process of step S20 that the driver set vehicle speed value has been changed, the process proceeds to step S21.

[0141] Then, in step S21, the cruise control unit 22 sets a new driver set vehicle speed value in accordance with the change operation (changing the setting of the driver set vehicle speed value), and then proceeds to the process of step S22.

[0142] On the other hand, if the change operation of the driver set vehicle speed value is not confirmed in the process of step S20, the process proceeds to the process of step S22 without going through the process of step S21. In this case, the setting of the driver set vehicle speed value is maintained at the value set before the start of traveling in FIG.

[0143] Then, in step S22, the cruise control unit 22 checks whether the currently set driver set vehicle speed value (for example, the value set before the start of travel in FIG. 2 or the value updated in step S21 in FIG. 3) is less than the currently set temporary set vehicle speed value (the value set in either step S17 in FIG. 2 or step S19 in FIG. 2). If the current driver set vehicle speed value is less than the currently set temporary set vehicle speed value, the process proceeds to step S23.

[0144] Next, in step S23, the cruise control unit 22 sets the currently set driver set vehicle speed value as a new temporary set vehicle speed value, and then proceeds to the process of step S24.

[0145] On the other hand, if it is determined in step S22 that the current driver-set vehicle speed value exceeds the current provisionally-set vehicle speed value, the process skips step S23 and proceeds to step S24 while maintaining the current provisionally-set vehicle speed value.

[0146] Then, in step S24, the cruise control unit 22 starts the ACC control based on the currently set temporary vehicle speed value.

[0147] The process of steps S22 to S23 will be described in more detail. The temporarily set vehicle speed value set at the time of step S22 is a vehicle speed value lower than the vehicle speed of the preceding vehicle. Also, as described above, the driver set vehicle speed value may have been changed to a lower value in steps S20 to S21.

[0148] In other words, if in the processing of the above-mentioned step S22, the current driver set vehicle speed value is less than the current provisional set vehicle speed value (= a vehicle speed value lower than the vehicle speed of the preceding vehicle), it can be assumed that the current driver set vehicle speed value has been changed downward in the processing of the above-mentioned steps S20 to S21.

[0149] Therefore, at this point in time, even if the vehicle travels at a current temporary set vehicle speed value (a vehicle speed value lower than the vehicle speed of the preceding vehicle) that exceeds the current driver set vehicle speed value, the vehicle speed value lower than the vehicle speed of the preceding vehicle is maintained, so there is no possibility of catching up with the preceding vehicle. Therefore, in this case, the temporary set vehicle speed value is set to be raised to the current driver set vehicle speed value in the process of step S23. In this case, even if the vehicle travels at the temporary set vehicle speed value, the vehicle will not exceed the speed limit and will not catch up with the preceding vehicle, so safe travel can be maintained.

[0150] On the other hand, if the current driver set vehicle speed value exceeds the current provisional set vehicle speed value in the processing of step S22 described above, it can be assumed that there is no change to the driver set vehicle speed value, and that the driver set vehicle speed value set before the start of driving in Figure 2, for example, is maintained.

[0151] Therefore, if the vehicle maintains the current temporarily set vehicle speed value, there is no possibility that the vehicle will catch up with the preceding vehicle. Therefore, in this case, the process skips step S23 and proceeds to step S24 while maintaining the current temporarily set vehicle speed.

[0152] Then, when the ACC control is started in the process of step S24, the cruise control unit 22 checks in step S25 whether or not the preceding vehicle is no longer recognized. If the preceding vehicle is no longer recognized, the process proceeds to the next step S26. If the preceding vehicle is recognized, the process is repeated until the preceding vehicle is no longer recognized while continuing the ACC control started in the process of step S24 described above. In this way, when it is confirmed that the preceding vehicle is no longer recognized, the process proceeds to the next step S26.

[0153] In step S26, the cruise control unit 22 registers the currently set temporary vehicle speed value as a registered set vehicle speed value for ACC control. Then, the cruise control unit 22 continues the ACC control based on the registered set vehicle speed value. After that, the process proceeds to step S27 in FIG. 4 (see circled number (4) in FIG. 3 and FIG. 4).

[0154] As described above (step S11 in FIG. 2 to step S26 in FIG. 3), in the driving control device 1 of this embodiment, the ACC control that is executed when the ECO ACC control mode is selected is executed when the following conditions are met. That is, (1) There is a preceding vehicle (step S13), (2) The vehicle speed exceeds the speed limit of the road (step S14). (3) If the current registered set vehicle speed value is equal to or greater than the vehicle speed value of the preceding vehicle (step S15), (4) And if the following vehicle has not been detected continuously for a predetermined period of time or longer (step S16), It is.

[0155] In this case, the cruise control device 1 of this embodiment sets a predetermined speed value lower than the vehicle speed of the preceding vehicle as the temporary set vehicle speed value (step S17). The temporary set vehicle speed value set in this case is automatically set within a predetermined range with the predetermined value of the road speed limit standard as the lower limit (step S19) and the driver set vehicle speed as the upper limit (step S22).

[0156] Here, the predetermined value of the speed limit standard of the road is set as the lower limit of the provisional set vehicle speed value as a measure to consider smooth passage. In this situation, it can be assumed that the vehicle itself and surrounding vehicles including the preceding vehicle are traveling at a speed exceeding the speed limit of the road. Therefore, if the vehicle itself performs a traveling control that complies with the speed limit under such a situation, the vehicle itself will travel against the traffic flow of the surrounding vehicles, and as a result, there is a possibility that a dangerous situation will occur. Therefore, in the traveling control device 1 of this embodiment, even if the traveling control is performed at a vehicle speed value that exceeds the speed limit of the road on which the vehicle is traveling, the traveling control is performed so that the traveling control can be performed smoothly according to the traffic flow without impeding the traffic flow of the surrounding vehicles. In addition, the driver set vehicle speed value is set as the upper limit of the provisional set vehicle speed value as a measure to reflect the driver's intention.

[0157] The ACC control based on the temporarily set vehicle speed value thus automatically is started (step S24). Since the automatically set temporarily set vehicle speed value does not fall below a predetermined value of the speed limit standard, the vehicle is controlled to travel in accordance with the flow of traffic of surrounding vehicles. Therefore, even if the vehicle decelerates, it does not disrupt smooth traffic.

[0158] In addition, since the driving control is not performed at a speed exceeding the driver set vehicle speed value, it is possible to perform efficient and safe driving control. At the same time, since the driving speed can be controlled to be suppressed, it is also possible to contribute to improving the fuel consumption rate. Furthermore, since the temporary set vehicle speed value is set to be lower than the vehicle speed value of the preceding vehicle, the driving control is performed to increase the distance between the vehicle and the preceding vehicle, so that the vehicle does not catch up with the preceding vehicle, and therefore the danger caused by approaching the preceding vehicle, etc. can be avoided in advance.

[0159] In this way, the distance between the vehicle and the preceding vehicle gradually increases, and the preceding vehicle moves away from the vehicle, so that the vehicle no longer recognizes the presence of the preceding vehicle. Then, the cruise control device 1 of the vehicle sets the temporary set vehicle speed value to the registered set vehicle speed value, and the ACC control is continued based on the registered set vehicle speed, so that safe driving can be maintained.

[0160] In the driving control device 1 of this embodiment, the basic operation of the ACC control executed when the ECO ACC control mode is selected has been described above (step S11 in FIG. 2 to step S26 in FIG. 3).

[0161] Here, the basic operation of the ACC control when the ECO ACC control mode is selected by the driving control device 1 of this embodiment will be briefly described again below using a specific example. Figure 5 is a conceptual diagram for explaining the process sequence of step S11 in Figure 2 to step S26 in Figure 3 using a specific example.

[0162] In Fig. 5, the reference symbol M indicates a host vehicle equipped with the cruise control device 1 of this embodiment. The host vehicle M is assumed to be traveling on a road 100 with the cruise control device 1 activated. Here, the road 100 shown in Fig. 5 is illustrated as, for example, a road with three lanes on each side. In this case, the oncoming lane of the road is omitted from the illustration.

[0163] It is assumed that the vehicle M is traveling in the center lane of the three lanes on the road 100. In addition, it is assumed that the speed limit of the road 100 is indicated by a speed limit sign 110 as 80 km / h.

[0164] 5 is running with the ACC control being performed with the driver set vehicle speed value DS set to 90 km / h, for example. In other words, the vehicle M is running at a vehicle speed V1 of 90 km / h, which is faster than the speed limit (if "Y" in step S14).

[0165] At this time, as shown in Fig. 5, a leading vehicle M2 is present in the vehicle's lane ahead of the vehicle M, and the vehicle M recognizes the leading vehicle M2 (if "Y" in step S13). Here, in Fig. 5, the range indicated by the symbol VA shown by the two-dot chain line conceptually indicates the recognition range of the camera unit 21, which is the surrounding environment recognition device.

[0166] In this case, a situation in which the vehicle M2 ahead is recognized by the vehicle M may be, for example, when the vehicle M approaches the vehicle M2 ahead. In this manner, when the vehicle M approaches the vehicle M2 ahead, it can be estimated that the recognized vehicle M2 ahead is traveling at a lower vehicle speed (for example, the vehicle speed V2 of the vehicle M2 ahead = 85 km / h) than the vehicle speed V1 of the vehicle M ahead (driver set vehicle speed value DS = 90 km / h) (if "Y" in step S15).

[0167] Another situation in which the host vehicle M recognizes the preceding vehicle M2 may be when another vehicle changes lanes from an adjacent lane to cut in front of the host vehicle M on the host vehicle's own lane (not shown). In this case, the host vehicle M recognizes the cutting in vehicle as a new preceding vehicle M2. For example, the state shown in Fig. 5 corresponds to a state in which the preceding vehicle M2 cuts in front of the host vehicle M from an adjacent lane by changing lanes and then travels ahead of the host vehicle M on the host vehicle's own lane.

[0168] In this situation, the host vehicle M is assumed to be cruising based on the driver set vehicle speed value DS=90km / h. In this case, if the vehicle speed V2 of the preceding vehicle M2 (another vehicle that has cut in) is faster (for example, V2=100km / h) than the vehicle speed of the host vehicle M (driver set vehicle speed value DS=90km / h), the preceding vehicle M2 is expected to gradually move away from the host vehicle M. On the other hand, if the vehicle speed V2 of the preceding vehicle M2 is slower (for example, V2=85km / h) than the host vehicle M, the host vehicle M is expected to approach the preceding vehicle M2 and eventually catch up with it (step S15). Note that FIG. 5 illustrates an example in which the vehicle speed V2 of the preceding vehicle M2 is 85km / h.

[0169] Therefore, the current set vehicle speed value of the host vehicle M (driver set vehicle speed value DS = 90 km / h) is compared with the vehicle speed value of the preceding vehicle M2, and if the vehicle speed of the host vehicle M is faster than the vehicle speed of the preceding vehicle M2 (if "Y" in step S15), the host vehicle M checks whether there is a following vehicle (not shown), and after confirming that there is no following vehicle (if "N" in step S16), starts ACC control in Eco ACC control mode (step S17).

[0170] In addition, if the comparison between the current set vehicle speed value of the host vehicle M and the vehicle speed value of the preceding vehicle M2 shows that the vehicle speed of the host vehicle M is slower than the vehicle speed of the preceding vehicle M2, the vehicle M will maintain its vehicle speed and continue traveling (if "N" in step S15).

[0171] When the ACC control in the eco ACC control mode is started in this manner, first, the host vehicle M sets a vehicle speed value lower than the vehicle speed value (V2=85 km / h) of the preceding vehicle M2 as the temporary set vehicle speed value TS (step S17).

[0172] In this case, if the temporary set vehicle speed value TS is set to, for example, a speed value obtained by subtracting 10% from the vehicle speed value (V2=85km / h) of the preceding vehicle M2, the temporary set vehicle speed value TS=76.5km / h.

[0173] If the temporary set vehicle speed value TS=76.5 km / h is less than the speed limit reference predetermined value SL ("Y" in step S18), the speed limit reference predetermined value SL is set as a new temporary set vehicle speed value TS (step S19).

[0174] Here, for example, if a speed value that is 10% less than the speed limit (80 km / h) is set as the predetermined value SL of the speed limit standard, the predetermined value SL of the speed limit standard becomes 72 km / h.

[0175] In this case, the temporary set vehicle speed value TS=76.5km / h is equal to or greater than the speed limit standard predetermined value SL=72km / h ("N" in step S18), so the temporary set vehicle speed value TS=76.5km / h is maintained as is.

[0176] Also, for example, as another example of the predetermined value SL of the speed limit standard, if a speed value equal to the speed limit (80 km / h) is set as shown in FIG. 5, the predetermined value SL of the speed limit standard becomes 80 km / h.

[0177] In this other example, since the temporary set vehicle speed value TS=76.5km / h is less than the speed limit reference predetermined value SL=80km / h, the speed limit reference predetermined value SL is set as the new temporary set vehicle speed value TS (step S19). That is, the temporary set vehicle speed value TS is updated from 76.5km / h to 80km / h.

[0178] Also, if the driver set vehicle speed value DS has been changed at this time, the driver set vehicle speed value DS is changed. Here, for example, if there is no change operation of the driver set vehicle speed value DS, the driver set vehicle speed value DS=90km / h is maintained (if "N" in step S20).

[0179] On the other hand, if the driver set vehicle speed value DS has been changed to a lower value, the changed driver set vehicle speed value DS is set.

[0180] For example, it is assumed that the current driver set vehicle speed value DS=90 km / h is changed downward to a new driver set vehicle speed value DS=70 km / h (if "Y" in step S20).

[0181] Here, the current temporary set vehicle speed value TS = 76.5km / h or 80km / h is compared with the current driver set vehicle speed value DS = 90km / h or 70km / h, and if the current driver set vehicle speed value DS is equal to or greater than the current temporary set vehicle speed value TS (if "N" in step S22), the current temporary set vehicle speed value TS is maintained, and if the current driver set vehicle speed value DS is less than the current temporary set vehicle speed value TS (if "Y" in step S22), the driver set vehicle speed value DS is newly set as the temporary set vehicle speed value TS (step S23).

[0182] Here, in the above example, when the current temporary set vehicle speed value TS=76.5km / h and the driver set vehicle speed value=90km / h ("N" in step S22), the current temporary set vehicle speed value TS=76.5km / h is maintained.

[0183] In addition, in the above-mentioned examples, when the current temporary set vehicle speed value TS=76.5km / h and the driver set vehicle speed value=70km / h ("Y" in step S22), the driver set vehicle speed value DS is set as the temporary set vehicle speed value TS (step S23). That is, the temporary set vehicle speed value TS is updated from 76.5km / h to 70km / h.

[0184] Furthermore, in the above examples, when the current temporary set vehicle speed value TS=80km / h and the driver set vehicle speed value DS=90km / h ("N" in step S22), the current temporary set vehicle speed value TS=80km / h is maintained.

[0185] In the above example, when the current temporary set vehicle speed value = TS 80km / h and the driver set vehicle speed value DS = 70km / h ("Y" in step S22), the driver set vehicle speed value DS is set as the temporary set vehicle speed value TS (step S23). That is, the temporary set vehicle speed value TS is updated from 80km / h to 70km / h.

[0186] Then, the ECO ACC control is started with the current temporary set vehicle speed value TS=76.5km / h, 70km / h, or 80km / h. The temporary set vehicle speed value TS thus set is a vehicle speed value lower than the vehicle speed V2 of the preceding vehicle in any case. Therefore, the host vehicle M will soon reach a state where it does not recognize the preceding vehicle M2.

[0187] Then, when the host vehicle M does not recognize the preceding vehicle M2, the cruise control device 1 registers the current temporary set vehicle speed value TS as the registered set vehicle speed value and continues the ECO ACC control, thereby allowing the host vehicle M to continue traveling safely.

[0188] In this way, (1) There is a preceding vehicle (step S13), (2) The vehicle speed exceeds the speed limit of the road (step S14). (3) If the current registered set vehicle speed value is equal to or greater than the vehicle speed value of the preceding vehicle (step S15), (4) And if the following vehicle has not been detected continuously for a predetermined period of time or longer (step S16), When the above conditions are met, the registered set vehicle speed value of the host vehicle M is appropriately set to a temporary set vehicle speed value that is lowered under specified conditions, and the host vehicle M can increase the distance between the host vehicle M and the preceding vehicle M2.

[0189] In the ACC control in the eco ACC control mode in the driving control device 1 of this embodiment, in addition to the basic action of the above-mentioned processing sequence (steps S11 to S26), control is further performed according to the processing sequence shown in the processing of step S27 and subsequent steps in Fig. 4. The processing sequence after the processing of step S27 illustrates driving control that takes into account other vehicles other than the preceding vehicle and the following vehicle described above, that is, vehicles running parallel to each other in the left and right lanes, among other vehicles running near the vehicle. In addition to this, driving control that takes into account the situation of an oncoming lane is also illustrated.

[0190] First, it is assumed that the ACC control based on the registered set vehicle speed value set in the process of step S26 in Fig. 3 is continued. At this time, in step S27 in Fig. 4, the cruise control unit 22 checks whether or not another vehicle is recognized near the host vehicle in the left adjacent lane.

[0191] In this case, the host vehicle is assumed to be traveling in a lane other than the leftmost lane on a multi-lane road as shown in Fig. 5, etc. The example shown in Fig. 6 shows a situation in which the host vehicle is traveling in the center lane of a three-lane road and another vehicle is traveling near the host vehicle in the adjacent lane to the left. Note that the situation is not limited to the example shown in Fig. 6, and may be, for example, a situation in which the host vehicle is traveling in the right lane of a two-lane road.

[0192] In the process of step S27 in FIG. 4, if another vehicle is recognized near the own vehicle in the adjacent lane to the left of the own lane, the process proceeds to step S28.

[0193] Next, in step S28, the cruise control unit 22 detects the vehicle speed value of the other vehicle in the recognized left adjacent lane, and checks whether the vehicle speed value of the other vehicle in the left adjacent lane and the current registered set vehicle speed value of the host vehicle (i.e., the current vehicle speed of the host vehicle) are approximately equal to each other. The detection of the vehicle speed of the other vehicle in the left adjacent lane can be performed by a well-known technique that calculates the speed based on the detection result of the surrounding environment recognition sensor 20a, such as a millimeter wave radar, included in the periphery monitoring unit 20.

[0194] If it is confirmed in step S28 that the vehicle speed of the other vehicle in the left adjacent lane and the temporarily set vehicle speed of the subject vehicle are substantially equal to each other, the process proceeds to step S29.

[0195] Then, in step S29, the cruise control unit 22 performs cruise control using the currently set driver set vehicle speed value instead of the currently registered set vehicle speed value. This causes the host vehicle to travel at a faster speed than the other vehicle in the left adjacent lane. Therefore, the host vehicle moves forward away from the other vehicle in the left adjacent lane, and the distance between the host vehicle and the other vehicle can be increased. Then, the process returns to step S12 in FIG. 2.

[0196] In addition, if the processing of step S28 determines that the vehicle speed value of the other vehicle in the adjacent lane to the left and the provisional set vehicle speed value of the vehicle itself are not approximately equal, control based on the currently registered set vehicle speed value is continued without going through the processing of step S29, and the processing returns to step S12 in FIG. 2.

[0197] On the other hand, if it is determined in the process of step S27 that no other vehicle is recognized near the vehicle in the left adjacent lane, the process proceeds to step S30.

[0198] Next, in step S30 of FIG. 4, the cruise control unit 22 checks whether or not another vehicle has been recognized near the host vehicle in the right adjacent lane.

[0199] In this case, the host vehicle is assumed to be traveling in a lane other than the rightmost lane on a multi-lane road as shown in Fig. 5, etc. The example shown in Fig. 7 shows a situation in which the host vehicle is traveling in the center lane of a three-lane road and another vehicle is traveling near the host vehicle in the adjacent lane to the right. Note that the situation is not limited to the example shown in Fig. 7, and may be, for example, a situation in which the host vehicle is traveling in the right lane of a two-lane road.

[0200] In the process of step S30 in FIG. 4, if another vehicle is recognized near the own vehicle in the adjacent lane to the right of the own lane, the process proceeds to step S31.

[0201] Next, in step S31, the cruise control unit 22 detects the vehicle speed value of the other vehicle in the recognized right adjacent lane, and checks whether the vehicle speed value of the other vehicle in the right adjacent lane and the current registered set vehicle speed value of the host vehicle (i.e., the current vehicle speed of the host vehicle) are approximately equal to each other. Note that the detection of the vehicle speed of the other vehicle in the right adjacent lane can be obtained by a well-known technique that calculates the speed based on the detection result of the surrounding environment recognition sensor 20a, such as a millimeter wave radar included in the periphery monitoring unit 20, in the same manner as the detection of the vehicle speed of the other vehicle in the left adjacent lane described above.

[0202] If it is confirmed in step S31 that the vehicle speed of the other vehicle in the adjacent lane to the right is substantially equal to the registered set vehicle speed of the subject vehicle, the process proceeds to step S32.

[0203] Then, in step S32, the cruise control unit 22 sets a new temporary set vehicle speed value that is a predetermined value lower than the current registered set vehicle speed value, and performs cruise control based on this new temporary set vehicle speed value. As a result, the host vehicle travels at a slower speed than the other vehicle in the right adjacent lane. Therefore, the host vehicle moves backward away from the other vehicle in the right adjacent lane, and the distance between the host vehicle and the other vehicle can be increased. Then, the process returns to step S12 in FIG. 2.

[0204] In this case, it is desirable to reduce the registered set vehicle speed value by a large amount, for example, about 20 to 30 percent.

[0205] Although not shown in the processing sequence of Fig. 4, when driving control is executed by significantly lowering the registered set vehicle speed value, the host vehicle may additionally carry out processing to confirm the presence of a following vehicle, similar to the above-mentioned step S16 (see Fig. 2). In this case, when a situation such as the approach of a following vehicle on the host vehicle's own lane behind the host vehicle is confirmed, processing such as reducing the reduction range of the vehicle speed value may be appropriately carried out.

[0206] In addition, if the processing of step S32 finds that the vehicle speed value of the other vehicle in the adjacent lane to the right and the provisional set vehicle speed value of the vehicle itself are not approximately equal, control based on the currently registered set vehicle speed value is continued without going through the processing of step S32, and the processing returns to step S12 in FIG. 2.

[0207] On the other hand, if it is determined in the process of step S30 that no other vehicle is recognized near the vehicle in the right adjacent lane, the process proceeds to step S33.

[0208] 4, the cruise control unit 22 checks the frequency of the brake lights of the preceding vehicle on the vehicle's lane. Here, the frequency of the brake lights refers to the frequency with which the brake lights are repeatedly turned on and off. In general, it is assumed that the higher the frequency of the brake lights being turned on, the more complicated the driving, such as repeated sudden acceleration and deceleration, is.

[0209] Therefore, in the cruise control device 1 of this embodiment, the frequency with which the brake lights of the preceding vehicle are turned on is confirmed in the process of step S33 in Fig. 4. If it is confirmed that the frequency with which the brake lights of the preceding vehicle are turned on is high, the process proceeds to step S32.

[0210] Then, in the process of step S32, a new temporary set vehicle speed value is set by lowering the current registered set vehicle speed value by a predetermined value, and driving control is performed based on this new temporary set vehicle speed value. After that, the process returns to step S12 in FIG.

[0211] In this case, it is preferable that the registered set vehicle speed value is decreased by a larger amount as the frequency with which the brake lights of the preceding vehicle are turned on increases.

[0212] On the other hand, if it is confirmed in the process of step S33 that the lighting frequency of the brake lamps of the preceding vehicle is normal (the lighting frequency is not high), the process proceeds to step S34.

[0213] 4, the cruise control unit 22 checks the lateral position change of the preceding vehicle and checks whether the lateral position change of the preceding vehicle is equal to or greater than a predetermined threshold. Here, the lateral position change of the preceding vehicle refers to a behavior seen in the case of meandering, for example. Therefore, if the lateral position change of the preceding vehicle exceeds the predetermined threshold, it can be assumed that the preceding vehicle continues to drive dangerously.

[0214] Therefore, in the cruise control device 1 of this embodiment, the lateral position change of the preceding vehicle is confirmed in the process of step S34 in Fig. 4, and if it is confirmed that the lateral position change is equal to or greater than a predetermined threshold, the process proceeds to step S32. In this case, the predetermined threshold for the lateral position change is, for example, based on the vehicle width of the preceding vehicle, and it is assumed that the lateral position change is repeated by about half or more of the vehicle width.

[0215] Then, in the process of step S32, a new temporary set vehicle speed value is set by lowering the current registered set vehicle speed value by a predetermined value, and driving control is performed based on this new temporary set vehicle speed value. After that, the process returns to step S12 in FIG.

[0216] In this case, it is preferable that the registered set vehicle speed value is decreased by a larger amount as the lateral position change of the preceding vehicle increases.

[0217] On the other hand, if it is confirmed in the process of step S34 that there is little change in the lateral position of the preceding vehicle (or there is almost no lateral change), it is assumed that the preceding vehicle is traveling normally, and the process proceeds to step S35.

[0218] Next, in step S35, the cruise control unit 22 checks the congestion situation of the oncoming lane parallel to the road including the own lane. For example, a well-known technology that recognizes the surrounding situation based on image data acquired by the camera unit 21 is used to check the surrounding situation.

[0219] If it is determined that the oncoming lane is congested, the process proceeds to step S32. If the oncoming lane is not congested, the process returns to step S12 in FIG.

[0220] Then, in the process of step S32, a new temporary set vehicle speed value is set by lowering the current registered set vehicle speed value by a predetermined value, and driving control is performed based on this new temporary set vehicle speed value. After that, the process returns to step S12 in FIG.

[0221] As described above, in the process sequence of steps S27 to S32 in Fig. 4, driving control is performed taking into consideration other vehicles traveling in adjacent lanes on the left and right of the own vehicle lane. Also, in the processes of steps S33 and S34 in Fig. 4, driving control is performed taking into consideration abnormal behavior of a preceding vehicle. Furthermore, in the process of step S35 in Fig. 4, driving control is performed taking into consideration the surrounding conditions of the own vehicle, particularly the congestion conditions in the oncoming lane.

[0222] In general, when a vehicle travels on a road with multiple lanes, it is desirable for the vehicle to avoid traveling side by side with another vehicle traveling on an adjacent lane for a long period of time. When a vehicle travels on a road, if the vehicle travels side by side with another vehicle in close proximity for a long period of time, there is always a risk of contact, etc. For this reason, it is desirable to avoid situations where the vehicle travels side by side with another vehicle in close proximity as much as possible.

[0223] Furthermore, in road systems where traffic is typically driven on the left side of the road, a situation in which a vehicle traveling in the left-hand lane (driving lane) overtakes a vehicle traveling in the right-hand lane (passing lane) at a faster speed than the vehicle traveling in the right-hand lane (passing lane) is an undesirable situation, as it disrupts smooth traffic flow.

[0224] Therefore, in the processing sequence of steps S27 to S29 in Fig. 4, when the driving control device 1 of this embodiment confirms that the host vehicle is traveling in a lane other than the leftmost lane and that another vehicle is traveling in the left adjacent lane at approximately the same vehicle speed as the host vehicle, it performs control to avoid the host vehicle and the other vehicle in the left adjacent lane traveling side by side. To this end, the host vehicle switches from driving control based on the registered set vehicle speed value registered in the above-mentioned step S26 (Fig. 3) to driving control based on the currently set driver set vehicle speed value. As a result, the host vehicle is accelerated relative to the other vehicle in the left adjacent lane, so that the host vehicle can move ahead of the other vehicle in the left adjacent lane.

[0225] Fig. 6 shows a situation in which a vehicle traveling on a road having multiple lanes (a road with three lanes in each direction is shown) recognizes another vehicle in the vicinity of the vehicle in the adjacent lane to the left during driving control in the eco ACC control mode. Fig. 6 is a conceptual diagram for explaining the processing sequence of steps S27 to S29 in Fig. 4 by using a specific example.

[0226] The situation shown in FIG. 6 is a situation in which, after the processing sequence shown in FIGS. 2 and 3 has been executed, ACC control based on the registered set vehicle speed value registered in the processing of step S26 in FIG. 3 is continued.

[0227] That is, in Fig. 6, the reference symbol M indicates a host vehicle equipped with the cruise control device 1 of this embodiment. The host vehicle M is assumed to be traveling on a road 100 with the cruise control device 1 activated. Here, the road 100 shown in Fig. 6 is illustrated as, for example, a three-lane road on one side. In this case, the oncoming lane of the road is omitted from the illustration.

[0228] It is assumed that the vehicle M is traveling in the center lane of the three lanes on the road 100. In addition, it is assumed that the speed limit of the road 100 is indicated by a speed limit sign 110 as 80 km / h.

[0229] In such a situation, the host vehicle M shown in Fig. 6 is assumed to be running by executing ACC control at the registered set vehicle speed value RS = 80km / h registered in the process of step S26 in Fig. 3 in the above-mentioned processing sequence. Therefore, the host vehicle M is assumed to be running at a vehicle speed V1 = 80km / h at this time. In addition, the driver set vehicle speed value DS is assumed to be set to 90km / h.

[0230] At this time, the host vehicle M does not recognize the preceding vehicle in the process of step S25 in Fig. 3 (if "Y" in step S25). Therefore, there is no preceding vehicle in the host vehicle lane in front of the host vehicle M. In Fig. 6, the vehicle indicated by the dotted line with the symbol Ma indicates that the host vehicle M switches to a higher speed value (RS→DS) than the other vehicle M3 and continues traveling, as described below, and as a result, the host vehicle (Ma) is in a positional relationship away from the other vehicle M3.

[0231] On the other hand, at this time, the host vehicle M is in a state where it recognizes another vehicle M3 in the left adjacent lane near the host vehicle (in the case of "Y" in step S27 of FIG. 4). Here, the recognition of the other vehicle M3 in the left adjacent lane near the host vehicle can be detected, for example, by using the surrounding environment recognition sensor 20a of the periphery monitoring unit 20, as described above.

[0232] In FIG. 6, the ranges indicated by the symbols FR, FL, RR, and RL indicated by the two-dot chain lines conceptually indicate the recognition ranges of the surrounding environment recognition sensors 20a. Specifically, the range indicated by the symbol FR indicates the recognition range of the surrounding environment recognition sensor 20a arranged at the front right side position of the host vehicle M. Similarly, the range indicated by the symbol FL indicates the recognition range of the surrounding environment recognition sensor 20a arranged at the front left side position of the host vehicle M. Similarly, the range indicated by the symbol RR indicates the recognition range of the surrounding environment recognition sensor 20a arranged at the rear right side position of the host vehicle M. Similarly, the range indicated by the symbol RL indicates the recognition range of the surrounding environment recognition sensor 20a arranged at the rear left side position of the host vehicle M.

[0233] Therefore, FIG. 6 shows a situation in which the host vehicle M recognizes another vehicle M3 in the left adjacent lane near the host vehicle by the surrounding environment recognition sensor 20a arranged at the rear left side position. At this time, the host vehicle M also detects the vehicle speed of the other vehicle M3 in the left adjacent lane. In this case, the vehicle speed V3 of the other vehicle M3 is assumed to be substantially equal to the vehicle speed V1 of the host vehicle M (in the case of "Y" in step S28 of FIG. 4). In FIG. 6, the host vehicle M is assumed to be cruising at a registered set vehicle speed value RS = 80 km / s. Therefore, the vehicle speed V3 of the other vehicle M3 in the left adjacent lane is assumed to be approximately 80 km / h.

[0234] In such a situation, the host vehicle M switches to a driving control using the driver set vehicle speed value DS = 90 km / h instead of the registered set vehicle speed value RS = 80 km / h in order to avoid running side by side with the other vehicle M3 in the left adjacent lane (step S29 in FIG. 4). As a result, the host vehicle M moves forward away from the other vehicle M3 in the left adjacent lane, and the distance between the host vehicle M and the other vehicle M3 increases. The position of the host vehicle at this time is indicated by the symbol Ma in FIG. 6.

[0235] Next, in the processing sequence of steps S30 to S32 in Fig. 4, when the driving control device 1 of this embodiment confirms that the host vehicle is traveling in a lane other than the rightmost lane and another vehicle is traveling in the right adjacent lane at approximately the same vehicle speed as the host vehicle, it performs control to avoid the host vehicle and the other vehicle in the right adjacent lane running side by side. To this end, the host vehicle sets a new temporary set vehicle speed value that is a predetermined value lower than the registered set vehicle speed value registered in the above-mentioned step S26 (Fig. 3), and switches to driving control based on this new temporary set vehicle speed value. This allows the host vehicle to move away from the other vehicle in the right adjacent lane.

[0236] Fig. 7 shows a situation in which a vehicle traveling on a road having multiple lanes (a road with three lanes in each direction is shown) recognizes another vehicle in the vicinity of the vehicle in the adjacent lane to the right during driving control in the eco ACC control mode. Fig. 7 is a conceptual diagram for explaining the process sequence of steps S30 to S32 in Fig. 4 by using a specific example.

[0237] The situation shown in Fig. 7 is substantially similar to the situation described above in Fig. 6. Therefore, a description of the situation similar to Fig. 6 will be omitted, and only the differences will be described below.

[0238] Here, the situation in Figure 7 is similar to the situation in Figure 6 in that after the processing sequence shown in Figures 2 and 3 is executed, ACC control based on the registered set vehicle speed value registered in the processing of step S26 in Figure 3 continues to be performed.

[0239] Here, the host vehicle M shown in Fig. 7 is running by executing ACC control at a registered set vehicle speed value RS = 80km / h. Therefore, the vehicle speed V1 of the host vehicle M at this time is 80km / h. Note that the driver set vehicle speed value DS = 90km / h is set.

[0240] At this time, as shown in FIG. 7, there is no preceding vehicle in the vehicle's lane ahead of the vehicle M.

[0241] On the other hand, at this time, the host vehicle M recognizes another vehicle M4 in the right adjacent lane near the host vehicle (in the case of "Y" in step S30 of FIG. 4). Here, the recognition of the other vehicle M4 in the right adjacent lane near the host vehicle can be detected, for example, by using the surrounding environment recognition sensor 20a of the surroundings monitoring unit 20, as in the case of FIG. 6.

[0242] Therefore, FIG. 7 shows a situation in which the host vehicle M recognizes another vehicle M4 in the right adjacent lane near the host vehicle by the surrounding environment recognition sensor 20a arranged at the front right side position. At this time, the host vehicle M also detects the vehicle speed of the other vehicle M4 in the right adjacent lane. In this case, the vehicle speed V4 of the other vehicle M4 is assumed to be substantially equal to the vehicle speed V1 of the host vehicle M (in the case of "Y" in step S31 of FIG. 4). In FIG. 7, the host vehicle M is assumed to be cruising at a registered set vehicle speed value RS = 80 km / s. Therefore, the vehicle speed V4 of the other vehicle M4 in the right adjacent lane is assumed to be V4 ≈ 80 km / h.

[0243] In such a situation, in order to avoid running side by side with the other vehicle M4 in the right adjacent lane, the host vehicle M sets a temporary set vehicle speed value TS of 70 km / h, which is a predetermined value lower than the registered set vehicle speed value RS of 80 km / h, and switches to a driving control that uses this temporary set vehicle speed value TS (step S32 in FIG. 4). As a result, the host vehicle M moves backward away from the other vehicle M4 in the right adjacent lane, and the distance between the host vehicle M and the other vehicle M4 increases. The position of the other vehicle M4 at this time is indicated by the symbol M4a in FIG. 7.

[0244] Next, in the processing of steps S33 and S34 in FIG. 4, when the vehicle is following a preceding vehicle ahead of the vehicle on the vehicle's lane and abnormal behavior of the preceding vehicle is confirmed, the driving control device 1 of this embodiment reduces the vehicle speed of the vehicle, stops following the preceding vehicle, and performs driving control to move away from the preceding vehicle.

[0245] Here, the abnormal behavior of the preceding vehicle refers to, for example, a case where the brake lights of the preceding vehicle are turned on frequently (step S33), a case where the lateral position of the preceding vehicle changes significantly (step S34), and the like.

[0246] For this purpose, the host vehicle sets a new temporary set vehicle speed value that is a predetermined value lower than the registered set vehicle speed value registered in step S26 of Fig. 3, and switches to a driving control based on the new temporary set vehicle speed value. This allows the host vehicle to move away from the preceding vehicle.

[0247] In addition, the reference symbol BL shown in FIG. 5 conceptually indicates the lighting state of the brake lamps of the preceding vehicle M2.

[0248] Furthermore, in the processing of step S35 in FIG. 4, when the driving control device 1 of this embodiment confirms that the vehicle is following a preceding vehicle ahead of the vehicle in the vehicle's own lane and that the oncoming lane is congested, the driving control device 1 reduces the vehicle speed of the vehicle, cancels the following of the preceding vehicle, and performs driving control to reduce the speed.

[0249] For this purpose, the host vehicle sets a new temporary set vehicle speed value that is a predetermined value lower than the registered set vehicle speed value registered in step S26 of Fig. 3, and switches to driving control based on this new temporary set vehicle speed value. As a result, the host vehicle travels at a speed that allows it to stop at any time even if a pedestrian or the like suddenly appears, and therefore safe driving can be maintained.

[0250] Fig. 8 shows a situation where the oncoming lane is congested while the host vehicle is traveling in the host lane and is being controlled in the ECO ACC control mode. Fig. 8 is a conceptual diagram for explaining the process of step S35 in Fig. 4 by using a specific example.

[0251] Generally, there are many situations where traffic is flowing smoothly in the lane where the vehicle is traveling, but the other lane is congested. In such a situation, there is a possibility that a pedestrian or the like may walk between the congested vehicles in the oncoming lane and attempt to cross the road on the vehicle's lane. In such a case, if the vehicle is traveling at a relatively high speed on the vehicle's lane, it may not be able to avoid the pedestrian.

[0252] Therefore, in the cruise control device 1 of this embodiment, in a situation where the oncoming lane is congested, the presence of a pedestrian or the like jumping out from between the line of congested vehicles is assumed, and a temporary set vehicle speed value is set in advance that significantly reduces the vehicle speed of the host vehicle to a speed at which the host vehicle can be stopped at any time. This makes it possible to avoid a pedestrian or the like jumping out from between the line of congested vehicles.

[0253] The situation shown in Fig. 8 is a situation in which ACC control based on the registered set vehicle speed value registered in the process of step S26 in Fig. 3 continues to be performed after the process sequence shown in Fig. 2 and Fig. 3 is executed. In this respect, it is substantially similar to the situation shown in Fig. 6 and Fig. 7. However, in Fig. 8, the environment of the road on which the host vehicle is traveling is different from the environment shown in Fig. 6 and Fig. 7 in the following points.

[0254] That is, in FIG. 8, the symbol M indicates a host vehicle equipped with the cruise control device 1 of the present embodiment, as in FIG. 6 and FIG. 7. The host vehicle M is assumed to be traveling on a road 100A with the cruise control device 1 activated. Here, the road 100A shown in FIG. 8 is an example of a one-lane road. That is, the road 100A in FIG. 8 is a general road consisting of a host lane 101 on which the host vehicle M is traveling and an oncoming lane 102 installed parallel to the host lane 101 and on which oncoming vehicles are traveling. The speed limit of the road 100A is assumed to be 40 km / h indicated by a speed limit sign 110. And, on the road 100A, the host lane 101 side on which the host vehicle M is traveling is relatively busy, while the oncoming lane 102 side is congested with a line of multiple oncoming vehicles Mx.

[0255] In such a situation, the host vehicle M shown in Fig. 8 is assumed to be running by executing ACC control at the registered set vehicle speed value RS = 40 km / h, for example, in the process of step S26 in Fig. 3 among the above-mentioned processing sequence. Therefore, the host vehicle M is assumed to be running at a vehicle speed V1 = 40 km / h at this time.

[0256] At this time, the host vehicle M is in a state where it does not recognize the preceding vehicle in the process of step S25 in Fig. 3 (if "Y" in step S25). Therefore, there is no preceding vehicle in the host vehicle lane ahead of the host vehicle M, as shown in Fig. 6.

[0257] Meanwhile, at this time, the host vehicle M recognizes that the oncoming lane 102 is congested (in the case of "Y" in step S35 of FIG. 4). Here, the situation of the oncoming lane 102 is recognized by using a well-known technology that recognizes the surrounding situation using, for example, the camera unit 21, the surrounding monitoring unit 20, etc.

[0258] In such a situation, there is a possibility that a pedestrian or the like may jump out from between the line of vehicles in the oncoming lane 102. For example, in the example shown in Fig. 8, a pedestrian (see reference symbol H0) on the oncoming lane 102 of the road 100A walks between the line of vehicles in the oncoming lane 102 (see reference symbol H), and the pedestrian H further crosses the oncoming lane 102 (see reference symbol H1), eventually reaches the side of the own lane 101 (see reference symbol H2), and finally crosses the own lane 101 (see reference symbol H3).

[0259] In this case, while the host vehicle M is traveling, it constantly recognizes the environment ahead using, for example, the camera unit 21. Here, when a pedestrian is at the position indicated by the symbol H in Fig. 8, the pedestrian (H) is blocked by a line of vehicles in the oncoming lane 102 and is outside the recognition range VA of the camera unit 21 of the host vehicle M. Therefore, at this point in time, the host vehicle M is unable to recognize the pedestrian (H).

[0260] Thereafter, suppose that the pedestrian moves and reaches, for example, a position indicated by reference symbol H1 in Fig. 8. At this point, the pedestrian (H1) enters the recognition range VA of the camera unit 21 of the host vehicle M. Therefore, at this time, if there is no obstruction or the like between the host vehicle M and the pedestrian (H1), the host vehicle M can recognize the pedestrian (H1).

[0261] However, even while the pedestrian moves from the position indicated by the symbol H to the position indicated by the symbol H1, the host vehicle M moves forward. Therefore, the distance between the host vehicle M and the pedestrian at the time when the host vehicle M can recognize the pedestrian becomes closer as the vehicle speed V1 of the host vehicle M becomes faster, and the host vehicle M becomes more likely to collide with the pedestrian without being able to avoid the pedestrian.

[0262] Therefore, in the driving control device 1 of this embodiment, assuming that a pedestrian or the like may suddenly jump out from between the line of vehicles in the oncoming lane 102 during a traffic jam, a provisional set vehicle speed value is set in advance by significantly lowering the vehicle speed V1 of the host vehicle (40 km / h in the example of Figure 8) to a speed at which the host vehicle can be stopped at any time (for example, approximately 50% lower than the vehicle speed of the host vehicle M; V1 = approximately 20 km / h).

[0263] As a result, even if a pedestrian or the like jumps out between vehicles in the oncoming lane 102 when the oncoming lane 102 is congested, the vehicle M can easily take evasive action by performing emergency braking control or the like.

[0264] In the above description, the vehicle speeds (V2 to V4) of the preceding vehicle, the following vehicle, and the vehicles traveling side by side in the adjacent lanes on the left and right are detected in the cruise control device 1 of this embodiment by detecting the absolute values ​​of the vehicle speeds, but the present invention is not limited to this example. When detecting the vehicle speed of another vehicle, the vehicle speed may be detected by detecting the relative speed between the vehicle and the target vehicle, for example.

[0265] As described above, in explaining this embodiment, a case where the present embodiment is compatible with a road system based on left-hand traffic is taken as an example. Therefore, in explaining this embodiment, the left adjacent lane mainly refers to the driving lane. Also, in explaining this embodiment, the right adjacent lane mainly refers to the passing lane. Therefore, in order to apply this embodiment to a right-hand traffic system, the left adjacent lane should be considered as the passing lane and the right adjacent lane should be considered as the driving lane.

[0266] As described above, according to the embodiment, in the driving control device of a vehicle equipped with a cruise control with vehicle distance control function (ACC control), during driving control by ACC control using a driver set speed value preset by the driver, a preceding vehicle is recognized, and if the vehicle speed of the vehicle exceeds the speed limit of the road, the current registered set speed value (driver set speed value) is equal to or higher than the vehicle speed value of the preceding vehicle, and if a following vehicle has not been detected continuously for a predetermined time or more, a vehicle speed value lower than the vehicle speed value of the preceding vehicle (a vehicle speed value obtained by subtracting a predetermined value from the vehicle speed value of the preceding vehicle) is set as a temporary set speed value to perform driving control. In this case, the temporary set speed value is set within a range with a lower limit set to a predetermined value of the speed limit standard of the road on which the vehicle is traveling, and an upper limit set to the temporary set speed value (a vehicle speed value lower than the vehicle speed value of the preceding vehicle).

[0267] As a result, the cruise control device 1 of this embodiment can greatly increase the distance between the host vehicle and the preceding vehicle. Also, since it is confirmed that there is no following vehicle at this time, the host vehicle can continue to travel almost alone at a set constant vehicle speed value. Therefore, the host vehicle can avoid traveling close to the preceding vehicle and the following vehicle, and therefore the safe travel of the host vehicle can be ensured.

[0268] In this case, the host vehicle performs driving control to move away from the preceding vehicle while suppressing the vehicle speed without going against the flow of traffic. This allows the host vehicle to maintain stable driving at a set constant vehicle speed without being affected by the behavior of the preceding vehicle. This makes it possible to suppress frequent acceleration and deceleration caused by being significantly affected by the behavior of the preceding vehicle, thereby maintaining a comfortable ride and safe driving. At the same time, it is possible to maintain stable driving control by suppressing the speed, which can also contribute to improving the fuel consumption rate.

[0269] In addition, the cruise control device 1 of this embodiment also appropriately controls the vehicle speed of the host vehicle for vehicles traveling side by side in lanes adjacent to the left and right of the host vehicle, thereby avoiding a situation in which the host vehicle and the vehicle traveling side by side run side by side. That is, the vehicle speed of the host vehicle is controlled to move the host vehicle ahead of the vehicle traveling side by side in the driving lane, while the vehicle speed of the host vehicle is controlled to slow down the host vehicle for the vehicle traveling side by side in the overtaking lane. This makes it possible to avoid a situation in which the host vehicle and the vehicle traveling side by side run close to each other, thereby ensuring the safe running of the host vehicle.

[0270] In this embodiment, the vehicle speed of the vehicle exceeds the speed limit of the road on which the vehicle is traveling as one of the conditions for performing the control to set a vehicle speed value lower than the vehicle speed of the preceding vehicle as the temporary set vehicle speed value, but the present invention is not limited to this. For example, instead of such a condition, the vehicle speed may exceed a predetermined speed value that is increased or decreased by a certain value based on the speed limit of the road. In other words, the condition for performing the control does not necessarily have to be, for example, the speed limit, but may be within a range of increased or decreased speed values ​​based on the speed limit. Therefore, it is desirable to be able to operate the control even when the speed value is exactly the same as the speed limit, or when the speed value is slightly lower than the speed limit (for example, when the speed value is 1 km / h lower).

[0271] The present invention is not limited to the above-mentioned embodiment, and various modifications and applications can be implemented within the scope of the gist of the invention. Furthermore, the above-mentioned embodiment includes inventions at various stages, and various inventions can be extracted by appropriate combinations of the disclosed multiple constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the above-mentioned one embodiment, if the problem to be solved by the invention can be solved and the effect of the invention can be obtained, the configuration from which the constituent elements are deleted can be extracted as the invention. Furthermore, the constituent elements across different embodiments may be appropriately combined. The present invention is not restricted by its specific embodiment except as limited by the attached claims. [Explanation of symbols]

[0272] 1...Drive control device 10…In-vehicle communication line 11...Locator unit 12...Map locator calculation unit 12a... Vehicle position estimation unit 12b…Map information acquisition section 13...Accelerometer 14...Wheel speed sensor 15...Gyro sensor 16...GNSS receiver 17...Road information receiver 18…High-precision road map database 19…Route information input section 20...Perimeter monitoring unit 20a…Surrounding environment recognition sensor 20b…Surrounding Area Awareness Department 21...Camera unit 21a…Main camera 21b…Sub camera 21c…Image Processing Unit (IPU) 21d…Driving environment recognition section 22...Drive control unit 22a...Steering assistance control unit 22b...Target driving route setting unit 22c…Set vehicle speed value setting section 23…Engine control unit 24...Power steering control unit 25…Brake control unit 27...Throttle actuator 28...Electric power steering motor 29…Brake actuator 33...Mode switch 34…Handle touch sensor 35...Steering torque sensor 36...Brake sensor 37...Accelerator sensor 38...Alarm device 100,100A…Road 101…own lane 102…Oncoming traffic 110…Speed ​​limit sign H…Pedestrian M…Own vehicle M2: Leading vehicle M3: Other vehicles in adjacent lane on the left M4: Other vehicles in adjacent lanes on the right and left Mx…Oncoming vehicle V1: Vehicle speed V2: Speed ​​of preceding vehicle V3: Vehicle speed of other vehicles in the adjacent lane on the left V4: Vehicle speed of other vehicles in the adjacent lane on the right DS: Driver set vehicle speed value RS…Registered set vehicle speed value SL: Speed ​​limit standard value TS: Temporary set vehicle speed value

Claims

1. A surrounding environment information acquisition device that acquires surrounding environment information of a vehicle; a vehicle status information acquisition device for acquiring a vehicle status; an external information receiving device for acquiring at least road map information from an external device; a set vehicle speed value setting unit that sets a target vehicle speed value when performing driving control; a driving control unit that controls a vehicle speed value of the host vehicle and controls driving of the host vehicle by taking other surrounding vehicles into consideration based on a plurality of pieces of information acquired using the surrounding environment information acquisition device, the host vehicle status information acquisition device, and the external information receiving device; Equipped with The driving control unit includes: A leading vehicle is recognized in front of the vehicle, The vehicle speed exceeds the speed limit of the road on which the vehicle is traveling or exceeds a predetermined speed value that is set by increasing or decreasing the speed limit by a certain amount. a driver set vehicle speed value preset by a driver is equal to or greater than the vehicle speed value of the preceding vehicle; When it is confirmed that a following vehicle has not been recognized behind the vehicle for a predetermined period of time or more, A vehicle driving control device characterized in that a vehicle speed value of the subject vehicle is set as a temporary set vehicle speed value, which is a predetermined value lower than the vehicle speed value of the preceding vehicle, and driving control is performed using the temporary set vehicle speed value.

2. The vehicle driving control device according to claim 1, characterized in that if a preceding vehicle cannot be recognized during driving control using the temporary set vehicle speed value, the currently set temporary set vehicle speed value is registered as a registered set vehicle speed value, and driving control using the registered set vehicle speed value is continued.

3. The vehicle driving control device according to claim 1, characterized in that, when the temporary set vehicle speed value is less than a predetermined speed value based on the speed limit value of the road on which the vehicle is traveling, the predetermined speed value based on the speed limit value is set as a new temporary set vehicle speed value.

4. 2. The vehicle driving control device according to claim 1, characterized in that, during driving control using the temporary set vehicle speed value, if the currently set temporary set vehicle speed value exceeds the currently set driver set vehicle speed value, the currently set driver set vehicle speed value is set as a new temporary set vehicle speed value.

5. When another vehicle traveling parallel to the vehicle in the adjacent lane on the left or right side is recognized during driving control using the registered set vehicle speed value, When it is detected that the vehicle speed value of the other vehicle is substantially equal to the vehicle speed value of the host vehicle, When the other vehicle is traveling alongside the vehicle in the travel lane, the vehicle switches to travel control using the driver set vehicle speed value, When the other vehicle is traveling alongside the vehicle on the overtaking lane, the vehicle sets a vehicle speed value obtained by subtracting a predetermined value from the registered set vehicle speed value as a new temporary set vehicle speed value, and switches to driving control using the new temporary set vehicle speed value.

3. The vehicle travel control device according to claim 2.

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