Lane change support device

Abstract

A control device 100 comprises: a recognition unit 130 that recognizes the situation in the surroundings of a vehicle; a lane change determination unit 150 that, when the recognition unit 130 has detected another vehicle which is travelling on an adjacent lane, determines whether or not a lane change is possible, on the basis of the speeds of the vehicle and said other vehicle relative to each other and on the basis of an inter-vehicle distance between the vehicle and said other vehicle; and a travel control unit 170 that is capable of performing the lane change on the basis of the determination result of the lane change determination unit 150. On the basis of a preset target speed, the travel control unit 170 is capable of further performing travel speed control to control the travel speed of the vehicle. When the travel speed control is performed, the lane change determination unit 150 determines whether or not a lane change is possible, on the basis of relative speeds when the travel speed of the vehicle is set to the target speed.

Description

Technical Field

[0001] The present invention relates to a lane change assistance device.

Background Art

[0002] In recent years, efforts have been actively made to provide access to a sustainable transport system that also takes into account vulnerable road users. As part of this effort, research and development on driving assistance technologies and autonomous driving technologies in vehicles such as automobiles have been carried out to further improve traffic safety and convenience. As an example of a driving assistance technology, Patent Document 1 below discloses a lane change assistance device that changes the lane of the host vehicle from the host lane to an adjacent lane.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional lane change assistance device, whether or not to change lanes is determined based on the relative speed with other vehicles according to the current traveling speed of the host vehicle. For this reason, for example, when the host vehicle is traveling at a low speed due to the influence of the preceding vehicle or the like, it may be difficult to execute a lane change.

[0005] The present invention provides a lane change assistance device capable of increasing the opportunity to execute a lane change.

Means for Solving the Problems

[0006] One aspect of the present invention is a lane change assistance device capable of executing a lane change of the host vehicle from the host lane in which the host vehicle is traveling to an adjacent lane adjacent to the host lane, A recognition unit that recognizes the surrounding situation of the host vehicle; When another vehicle traveling in the adjacent lane is detected by the recognition unit, a lane change determination unit that determines whether the lane change is possible based on the relative speed between the host vehicle and the other vehicle and the inter-vehicle distance between the host vehicle and the other vehicle; A driving control unit capable of executing the lane change based on the determination result of the lane change determination unit; Comprising; The driving control unit is further capable of executing driving speed control for controlling the driving speed of the host vehicle based on a preset target speed; When the driving speed control is being executed, the lane change determination unit determines whether the lane change is possible based on the relative speed when the target speed is the driving speed of the host vehicle; It is a lane change support device.

Effect of the Invention

[0007] According to the present invention, it is possible to provide a lane change support device capable of increasing the opportunity to execute a lane change.

Brief Description of the Drawings

[0008]

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Embodiments for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the lane change support device of the present invention will be described with reference to the drawings. In the following, the same or similar elements may be denoted by the same or similar reference numerals, and the description thereof may be omitted or simplified as appropriate.

[0010] <Overall Configuration of Vehicle System 1> FIG. 1 is a block diagram showing the overall configuration of a vehicle system 1 equipped with a control device 100 which is an embodiment of the lane change support device of the present invention. The vehicle (hereinafter referred to as the "host vehicle M") on which the vehicle system 1 is mounted is, for example, a two-wheeled, three-wheeled, or four-wheeled vehicle, and its drive source is an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination thereof. The electric motor operates using the electric power generated by a generator connected to the internal combustion engine, or the discharge power of a secondary battery or a fuel cell.

[0011] The vehicle system 1 includes, for example, a camera 10, a radar device 12, a LIDAR (Light Detection and Ranging) 14, an object recognition device 16, a communication device 20, an HMI (Human Machine Interface) 30, a vehicle sensor 40, a driver monitoring camera 50, a navigation device 60, an MPU (Map Positioning Unit) 70, a driving operator 80, a blinker 83, a control device 100, a traveling driving force output device 200, a brake device 210, and a steering device 220. These devices and apparatuses are connected to each other by a multiplex communication line such as a CAN (Controller Area Network) communication line, a serial communication line, a wireless communication network, or the like.

[0012] The camera 10 is, for example, a digital camera using a solid-state imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The camera 10 is attached to an arbitrary location of the host vehicle M on which the vehicle system 1 is mounted.

[0013] The radar device 12 emits radio waves such as millimeter waves around the host vehicle M, and detects radio waves (reflected waves) reflected by an object to detect at least the position (distance and azimuth) of the object. The radar device 12 is attached to an arbitrary location of the host vehicle M.

[0014] The LIDAR 14 irradiates light (or electromagnetic waves with a wavelength close to light) around the host vehicle M and measures scattered light. The LIDAR 14 detects the distance to an object based on the time from light emission to light reception. The irradiated light is, for example, pulsed laser light. The LIDAR 14 is attached to an arbitrary location of the host vehicle M.

[0015] The object recognition device 16 performs sensor fusion processing on the detection results of some or all of the camera 10, the radar device 12, and the LIDAR 14 to recognize the position, type, speed, etc. of the object. The object recognition device 16 outputs the recognition result to the control device 100. The object recognition device 16 may output the detection results of the camera 10, the radar device 12, and the LIDAR 14 to the control device 100 as they are.

[0016] The communication device 20 communicates with other vehicles existing around the host vehicle M, for example, using a cellular network, a Wi-Fi (registered trademark) network, Bluetooth (registered trademark), DSRC (Dedicated Short Range Communication), etc., or communicates with various server devices via a wireless base station.

[0017] The HMI 30 presents various information to the passengers of the host vehicle M and accepts input operations by the passengers. The HMI 30 includes various display devices, speakers, buzzers, touch panels, switches, keys, etc.

[0018] The vehicle sensor 40 includes a vehicle speed sensor that detects the traveling speed of the host vehicle M (so-called "vehicle speed"; hereinafter also simply referred to as "speed"), an acceleration sensor that detects acceleration, a yaw rate sensor that detects the angular velocity around the vertical axis, an azimuth sensor that detects the orientation of the host vehicle M, etc.

[0019] The driver monitor camera 50 is, for example, a digital camera using a solid-state imaging device such as a CCD or a CMOS. The driver monitor camera 50 is attached at an arbitrary location in the host vehicle M at a position and orientation capable of imaging the head of the passenger (hereinafter also referred to as "driver") sitting in the driver's seat of the host vehicle M from the front (in the orientation of imaging the face).

[0020] The navigation device 60 includes, for example, a GNSS (Global Navigation Satellite System) receiver 61, a navigation HMI 62, and a route determination unit 63. The navigation device 60 holds first map information 64 in a storage device such as an HDD (Hard Disk Drive) or a flash memory.

[0021] The GNSS receiver 61 identifies the position of the host vehicle M based on signals received from GNSS satellites. The position of the host vehicle M may be identified or supplemented by an INS (Inertial Navigation System) that utilizes the output of the vehicle sensor 40.

[0022] The navigation HMI 62 includes a display device, a speaker, a touch panel, keys, etc. The navigation HMI 62 may be partially or entirely shared with the aforementioned HMI 30.

[0023] The route determination unit 63 determines, for example, a route (hereinafter also referred to as a "map route") from the position of the host vehicle M identified by the GNSS receiver 61 (or an arbitrary input position) to the destination input by the occupant using the navigation HMI 62, with reference to the first map information 64. The first map information 64 is information in which the road shape is represented by, for example, links indicating roads and nodes connected by the links. The first map information 64 may include road curvature, POI (Point Of Interest) information, etc. The map route is output to the MPU 70.

[0024] The navigation device 60 may perform route guidance using the navigation HMI 62 based on the map route. The navigation device 60 may transmit the current position and the destination to the navigation server via the communication device 20 and acquire a route equivalent to the map route from the navigation server.

[0025] The MPU 70 includes, for example, a recommended lane determination unit 71, and holds second map information 72 in a storage device such as an HDD or a flash memory. The recommended lane determination unit 71 divides the route on the map provided from the navigation device 60 into a plurality of blocks (for example, divides every 100 [m] in the vehicle traveling direction), and determines a recommended lane for each block with reference to the second map information 72. The recommended lane determination unit 71 makes a determination such as which lane from the left the vehicle should drive in. When there is a branch point on the route on the map, the recommended lane determination unit 71 determines the recommended lane so that the host vehicle M can drive on a reasonable route for proceeding to the branch destination.

[0026] The second map information 72 is map information with higher accuracy than the first map information 64. The second map information 72 includes, for example, information on the center of the lane or information on the boundary of the lane. Further, the second map information 72 may include road information, traffic regulation information, address information, facility information, telephone number information, and the like. The second map information 72 may be updated at any time when the communication device 20 communicates with other devices.

[0027] The driving operator 80 includes, for example, a turn signal lever 81 and a steering wheel 82, as well as an accelerator pedal, a brake pedal, a shift lever, and other operators. A sensor for detecting the operation amount or the presence or absence of an operation is attached to the driving operator 80, and the detection result is output to a part or all of the control device 100, or the traveling driving force output device 200, the brake device 210, and the steering device 220.

[0028] The turn signal lever 81 is an operator for turning on or off the turn signal 83, and also functions as an operator for receiving an operation as a lane change request. Although details will be described later, the control device 100 detects a lane change request from the driver based on the driver performing a predetermined operation on the turn signal lever 81.

[0029] The turn signal 83 is a direction indicator provided at a position visible from the outside of the host vehicle M on each of the left side (e.g., the left front and the left rear) and the right side (e.g., the right front and the right rear) of the host vehicle M. The control device 100 lights (including flashing) or turns off the turn signal 83 in response to an operation on the turn signal lever 81.

[0030] The steering wheel 82 is an operator that receives a steering operation. Note that the steering wheel 82 does not necessarily have to be annular, and may be in the form of a deformed steering wheel, a joystick, buttons, or the like. Further, a steering grip sensor 84 is attached to the steering wheel 82. The steering grip sensor 84 is realized by, for example, a capacitance sensor or the like, and outputs a signal capable of detecting whether or not the driver is gripping the steering wheel 82 to the control device 100.

[0031] The control device 100 is a computer that comprehensively controls the entire host vehicle M, and includes, for example, a first control unit 120 and a second control unit 160. The first control unit 120 and the second control unit 160 are each realized, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Further, some or all of these components may be realized by hardware (including a circuitry portion) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by cooperation between software and hardware. The program may be stored in advance in a storage device such as an HDD or a flash memory of the control device 100.

[0032] <Configuration of the First Control Unit 120 and the Second Control Unit 160> FIG. 2 is a diagram showing an example of the configuration of the first control unit 120 and the second control unit 160. The first control unit 120 includes, for example, a recognition unit 130 and an action plan generation unit 140. The first control unit 120 realizes, for example, functions by AI (Artificial Intelligence) and functions by a pre-given model in parallel.

[0033] For example, the function of "recognizing an intersection" may be realized by executing in parallel the recognition of an intersection by deep learning or the like and the recognition based on pre-given conditions (such as signals capable of pattern matching, road markings, etc.), scoring both, and comprehensively evaluating them. Thereby, the reliability of autonomous driving is ensured.

[0034] The recognition unit 130 recognizes the surrounding situation of the host vehicle M based on information input from the camera 10, the radar device 12, and the LIDAR 14 via the object recognition device 16. Specifically, the recognition unit 130 recognizes the position of an object around the host vehicle M and the driving state of the object such as the speed and acceleration of the object. The position of the object is recognized, for example, as a position on the absolute coordinates with the representative point (such as the center of gravity or the center of the drive shaft) of the host vehicle M as the origin and is used for control. The position of the object may be represented by a representative point such as the center of gravity or a corner of the object, or may be represented by a region. The "state" of the object may include the acceleration or jerk of the object, or the "behavior state" (for example, whether the vehicle is changing lanes or about to change lanes). The objects recognized by the recognition unit 130 include another vehicle (hereinafter also referred to as "preceding vehicle") M1 traveling in front of the host vehicle M and another vehicle (hereinafter also referred to as "following vehicle") M2 traveling behind the host vehicle M.

[0035] In addition, the recognition unit 130 recognizes, for example, the driving environment in which the host vehicle M is traveling. For example, the recognition unit 130 compares the pattern of road markings obtained from the second map information 72 (for example, the arrangement of solid lines and broken lines) with the pattern of road markings around the host vehicle M recognized from the image captured by the camera 10 to recognize the driving lane of the host vehicle M. Note that the recognition unit 130 may recognize the driving lane by recognizing the road boundary (road boundary) including not only road markings but also road shoulders, curbs, median strips, guardrails, etc. In this recognition, the position of the host vehicle M acquired from the navigation device 60 and the processing result by the INS may be taken into account. Further, the recognition unit 130 may recognize a stop line, an obstacle, a red signal, a tollgate, and other road events.

[0036] When recognizing the driving lane, the recognition unit 130 recognizes the position and attitude of the host vehicle M with respect to the driving lane. For example, the recognition unit 130 may recognize, as the relative position and attitude of the host vehicle M with respect to the driving lane, the deviation of the reference point of the host vehicle M from the center of the lane and the angle formed with respect to the line connecting the centers of the lanes in the traveling direction of the host vehicle M. Alternatively, the recognition unit 130 may recognize the position of the reference point of the host vehicle M with respect to either side end of the driving lane (road marking or road boundary) as the relative position of the host vehicle M with respect to the driving lane.

[0037] The action plan generation unit 140 basically travels in the recommended lane determined by the recommended lane determination unit 71, and further generates a target trajectory for the host vehicle M to travel automatically (without the driver's operation) in the future so as to be able to respond to the surrounding situation of the host vehicle M. The target trajectory includes, for example, a speed element. For example, the target trajectory is expressed as a sequence of points (trajectory points) that the host vehicle M should reach. The trajectory points are points that the host vehicle M should reach at every predetermined travel distance (for example, about several [m]) in the along-road distance, and separately, the target speed and target acceleration at every predetermined sampling time (for example, about several decimal [sec]) are generated as part of the target trajectory. Also, the trajectory points may be the positions that the host vehicle M should reach at the sampling time at every predetermined sampling time. In this case, the information on the target speed and target acceleration is expressed by the interval of the trajectory points.

[0038] When generating the target trajectory, the action plan generation unit 140 may set an event for the automatic driving. The events for the automatic driving include a constant speed driving event, a low-speed following driving event, a lane change event, a branching event, a merging event, a takeover event, and the like. The action plan generation unit 140 generates a target trajectory according to the event that has been activated.

[0039] As an example, the action plan generation unit 140 includes a lane change determination unit 150 that determines whether a lane change is possible based on the driving environment of the host vehicle M recognized by the recognition unit 130. The lane change determination unit 150 determines whether a lane change is possible based on, for example, the relative speed between the host vehicle M and another vehicle and the inter-vehicle distance between the host vehicle M and the other vehicle when another vehicle traveling in an adjacent lane adjacent to the driving lane of the host vehicle M is detected.

[0040] Then, based on the determination by the lane change determination unit 150 that lane change is possible, the action plan generation unit 140 sets a lane change event or generates a target trajectory corresponding to the lane change event. As a result, the traveling control unit 170 described later is configured to be able to execute a lane change based on the determination result of the lane change determination unit 150. Note that since the specific details of the determination of whether lane change is possible by the control device 100 realized by the lane change determination unit 150 and the like will be described later, the description here is omitted.

[0041] The second control unit 160 controls the target trajectory generated by the action plan generation unit 140 so that the host vehicle M passes through it at the scheduled time. The second control unit 160 includes, for example, an acquisition unit 162, a speed control unit 164, and a steering control unit 166.

[0042] The acquisition unit 162 acquires information on the target trajectory (trajectory points) generated by the action plan generation unit 140 and stores it in a memory (not shown). The speed control unit 164 controls the traveling drive force output device 200 (see FIG. 1) or the brake device 210 (see FIG. 1) based on the speed element associated with the target trajectory stored in the memory. The steering control unit 166 controls the steering device 220 (see FIG. 1) according to the degree of curvature of the target trajectory stored in the memory. The processing of the speed control unit 164 and the steering control unit 166 is realized, for example, by a combination of feedforward control and feedback control.

[0043] In addition, the second control unit 160 further includes, for example, a notification control unit 167. The notification control unit 167 controls the HMI 30, the navigation HMI 62, etc., and executes various notifications (presents various information) to the passengers (e.g., the driver) of the host vehicle M. For example, when the control device 100 cancels a lane change, the notification control unit 167 executes a notification to the effect that the lane change has been canceled (see, for example, step S40 in FIG. 12). The notification to the effect that the lane change has been canceled is executed, for example, by displaying a message such as "The lane change has been canceled" on a display device such as the HMI 30 or the navigation HMI 62.

[0044] <Travel Control Unit 170> In the control device 100, for example, the action plan generation unit 140 (including the lane change determination unit 150) of the first control unit 120 and the acquisition unit 162, speed control unit 164, and steering control unit 166 of the second control unit 160 together constitute the travel control unit 170.

[0045] When the travel control unit 170 detects a driver's lane change request based on the operation of the driving operator 80 (e.g., the turn signal lever 81) by the driver, it executes control related to lane change in the host vehicle M based on the recognition result of the travel situation or travel environment of the host vehicle M recognized by the recognition unit 130. For example, when the travel control unit 170 detects a driver's lane change request, it determines the feasibility of lane change considering the travel situation of the host vehicle M and other vehicles around it, and starts the lane change when it determines that lane change is possible. Note that, as described above, the lane change executed by the control device 100 in response to an instruction (lane change request) from the driver is hereinafter also referred to as "intentional automatic lane change".

[0046] In addition, the travel control unit 170 is configured to be able to execute travel speed control for controlling the travel speed of the host vehicle M based on a target speed preset in advance by the driver, the manufacturer of the host vehicle M, or the like. Here, the travel speed control is such that when there is no preceding vehicle M1 in the travel lane (the host lane L1 described later) of the host vehicle M, the travel speed of the host vehicle M becomes the target speed, and when there is a preceding vehicle M1 in the travel lane of the host vehicle M, it is control to adjust the travel speed of the host vehicle M in accordance with the travel speed of the preceding vehicle M1. For example, when a preceding vehicle M1 exists in the travel lane of the host vehicle M during the execution of travel speed control, the travel control unit 170 drives the host vehicle M so that the travel speed of the host vehicle M becomes the target speed on the condition that an appropriate inter-vehicle distance can be ensured between the host vehicle M and the preceding vehicle M1. Therefore, if a preceding vehicle M1 traveling at a speed lower than the target speed exists in the travel lane of the host vehicle M during the execution of travel speed control, the host vehicle M can travel at substantially the same speed as the preceding vehicle M1 (i.e., a speed lower than the target speed) after the inter-vehicle distance between the host vehicle M and the preceding vehicle M1 reaches a predetermined distance.

[0047] Such driving speed control is generally referred to as "ACC (Adaptive Cruise Control)". Also in this embodiment, hereinafter, the driving speed control is also referred to as "ACC". By executing the ACC (that is, the driving speed control) by the driving control unit 170, the control device 100 can appropriately control the driving speed of the host vehicle M in consideration of the presence or absence of the preceding vehicle M1 in the driving lane (the host lane L1 described later) of the host vehicle M and its driving speed, and can reduce the fatigue of the driver of the host vehicle M while ensuring the safety of the host vehicle M.

[0048] Returning to FIG. 1, the driving force output device 200 outputs the driving force (torque) for the vehicle to travel to the drive wheels. The driving force output device 200 includes, for example, a combination of an internal combustion engine, an electric motor, and a transmission, etc., and an ECU (Electronic Control Unit) that controls these. The ECU controls the above configuration according to the information input from the second control unit 160 or the information input from the operation operator 80.

[0049] The brake device 210 includes, for example, a brake caliper, a cylinder that transmits hydraulic pressure to the brake caliper, an electric motor that generates hydraulic pressure in the cylinder, and a brake ECU. The brake ECU controls the electric motor according to the information input from the second control unit 160 or the information input from the operation operator 80, so that the brake torque corresponding to the braking operation is output to each wheel.

[0050] The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor, for example, acts on a rack and pinion mechanism to change the direction of the steered wheels. The steering ECU drives the electric motor according to the information input from the second control unit 160 or the information input from the operation operator 80, and changes the direction of the steered wheels.

[0051] <Steering wheel 82 and turn signal lever 81> FIG. 3 is a diagram showing an example of a steering wheel 82 and a turn signal lever 81. As shown in FIG. 3, the turn signal lever 81 is an operator provided at a position and in a shape that enables blind operation, for example, with one finger of one hand (e.g., the right hand) when the driver grips the steering wheel 82.

[0052] <Operation of turn signal lever 81> FIG. 4 is a diagram showing a specific example of the operation of the turn signal lever 81. As shown in FIG. 4, the turn signal lever 81 is capable of a pivoting operation about a pivot shaft 81a. The neutral position PN, the light push positions P1L, P1R, and the deep push positions P2L, P2R are the respective positions where the turn signal lever 81 can be displaced by pivoting.

[0053] The neutral position PN is the position where the turn signal lever 81 is not being operated. When the turn signal lever 81 is in the neutral position PN, the turn signal 83 is turned off.

[0054] The light push position P1L is a hollow position rotated a predetermined amount counterclockwise from the neutral position PN. The deep push position P2L is an end position rotated a predetermined amount further counterclockwise from the light push position P1L. The light push position P1R is a hollow position rotated a predetermined amount clockwise from the neutral position PN. The deep push position P2R is an end position rotated a predetermined amount further clockwise from the light push position P1R. The light push positions P1L, P1R are an example of the first position of the turn signal lever 81. The deep push positions P2L, P2R are an example of the second position of the turn signal lever 81.

[0055] When the turn signal lever 81 is tilted by the driver to the light push positions P1L, P1R, it gives the driver a click feeling, and when the operating force on the turn signal lever 81 is released from that state, it is mechanically returned to the neutral position PN by a return mechanism (not shown) such as a spring. Also, when the turn signal lever 81 is tilted by the driver to the deep push positions P2L, P2R, it is held at the deep push positions P2L, P2R even when the operating force is released by a mechanical locking mechanism (not shown).

[0056] The turn signal lever 81 is provided with a switch (not shown), and based on the detection result by this switch, the travel control unit 170 can determine whether the turn signal lever 81 is in any of the neutral position PN, the light push positions P1L, P1R, and the deep push positions P2L, P2R.

[0057] When the steering wheel 82 rotates reversely and returns to the neutral position while the turn signal lever 81 is held in the deep push positions P2L, P2R, or when the driver performs a return operation of the turn signal lever 81 in the direction of the neutral position, the lock by the lock mechanism is released and it returns to the neutral position PN. That is, when the turn signal lever 81 is operated to the deep push positions P2L, P2R, it operates in the same manner as a conventionally generally implemented turn signal flashing device.

[0058] Hereinafter, an operation of maintaining the turn signal lever 81 at the light push position P1L or the light push position P1R is referred to as a "half-lock operation". The half-lock operation is an example of a predetermined operation of the present invention. For example, when the half-lock operation of the turn signal lever 81 continues for a predetermined time or more, the control device 100 determines that there is a lane change request. Here, the predetermined time is the time required to confirm the driver's intention to change lanes, and as an example, it is 1.0 [sec]. In this way, by accepting a lane change request based on an operation on the turn signal lever 81 (for example, a half-lock operation), it becomes possible to accept a lane change request without providing an operation button or the like for accepting a lane change request separately from the turn signal lever 81.

[0059] <Lane change operation of the host vehicle M> When there is a lane change request from the driver during ACC execution, the control device 100 (for example, the travel control unit 170) can execute a lane change while maintaining ACC. FIG. 5 shows an example of the lane change operation of the host vehicle M during ACC execution by the control device 100.

[0060] The road 110 shown in FIG. 5 has a right lane 111 and a left lane 112, with the direction from bottom to top in FIG. 5 being the traveling direction. At the boundary between the right lane 111 and the left lane 112, a dividing line C as a road dividing line is provided.

[0061] In the example shown in FIG. 5, the host vehicle M is traveling in the right lane 111 of the road 110 by ACC. The traveling lane of the host vehicle M is also hereinafter referred to as the "host lane L1". Also, in the right lane 111, which is the host lane L1, there is a preceding vehicle M1 traveling at a speed lower than the target speed of the host vehicle M. And in the left lane 112 adjacent to the right lane 111, which is the host lane L1, there is a following vehicle M2 traveling. The lane adjacent to the host lane L1 is also hereinafter referred to as the "adjacent lane L2".

[0062] In a case like the example shown in FIG. 5, if the vehicle remains in the right lane 111 as it is, due to the influence of the preceding vehicle M1, the host vehicle M will also have to continue traveling at a speed lower than the target speed, so the driver often hopes to change lanes. In the example described here, it is assumed that the driver hopes to change lanes and makes a lane change request (for example, the aforementioned half-lock operation) to the control device 100.

[0063] Thus, when there is a lane change request from the driver while ACC is being executed and the host vehicle M is traveling at a speed lower than the target speed, the control device 100 first starts turning on the turn signal 83 and accelerates the host vehicle M in the right lane 111 (host lane L1). That is, when executing a lane change during the execution of ACC (i.e., traveling speed control), the control device 100 (for example, the traveling control unit 170) accelerates the host vehicle M based on the target speed before the movement of the host vehicle M to the adjacent lane L2 due to the lane change is completed. Thereby, it is possible to suppress the reduction of the inter-vehicle distance from the following vehicle M2 traveling in the adjacent lane L2 and execute the lane change while ensuring the safety of the host vehicle M.

[0064] Then, after time t1 from the start of acceleration, the control device 100 executes a lane change by laterally moving the host vehicle M to the left lane 112 (adjacent lane L2) while further accelerating the host vehicle M. More specifically, when executing a lane change during the execution of ACC (i.e., traveling speed control), the control device 100 (e.g., the travel control unit 170) accelerates the host vehicle M to the target speed before the movement to the adjacent lane L2 due to the lane change is completed.

[0065] As an example, in the present embodiment, the time t1 from the start of acceleration in the host lane L1 to the start of lateral movement is set to 3 [sec]. Also, the time t2 from the start of lateral movement to the completion of lateral movement (i.e., the completion of lane change) is set to 7 [sec]. That is, the control device 100 executes a lane change over 10 [sec] from when the turn signal 83 is turned on in response to a lane change request.

[0066] And when there is a lane change request from the driver while ACC is being executed and the host vehicle M is traveling at a speed lower than the target speed, the control device 100 executes a lane change while accelerating the host vehicle M at a constant acceleration so that the host vehicle M reaches the target speed at the completion of the lane change. For example, as described above, when executing a lane change over 10 [sec], the acceleration of the host vehicle M during this lane change is (target speed - speed immediately before the start of lane change) / 10 [km / s 2 and is so set.

[0067] Thus, when executing a lane change while ACC is being executed and the host vehicle M is traveling at a speed lower than the target speed, the host vehicle M is accelerated to the target speed before the movement to the adjacent lane L2 due to the lane change is completed. Thereby, it is possible to suppress the reduction in the inter-vehicle distance with the following vehicle M2 traveling in the adjacent lane L2 and execute a lane change while ensuring the safety of the host vehicle M. Also, when accelerating the host vehicle M in this way along with the execution of a lane change, by making the acceleration constant, it is possible to suppress the occurrence of unexpected acceleration fluctuations during the lane change and avoid giving the driver a sense of unease or discomfort while executing a lane change.

[0068] <Lane change determination process> Incidentally, as shown in FIG. 5, when there is a following vehicle M2 traveling in the adjacent lane L2 when a lane change request is made, the lane change determination unit 150 determines whether a lane change is possible based on the relative speed between the host vehicle M and the following vehicle M2 and the inter-vehicle distance between the host vehicle M and the following vehicle M2.

[0069] Specifically, in the present embodiment, as shown in FIG. 6, the minimum inter-vehicle distance at which a lane change can be executed is determined in advance for each relative speed. Then, the lane change determination unit 150 first calculates the relative speed between the host vehicle M and the following vehicle M2 by subtracting the speed of the host vehicle M from the speed of the following vehicle M2, and compares the minimum inter-vehicle distance corresponding to the calculated relative speed with the inter-vehicle distance between the host vehicle M and the following vehicle M2. As a result, when the inter-vehicle distance between the host vehicle M and the following vehicle M2 is equal to or greater than the minimum inter-vehicle distance corresponding to the relative speed between the host vehicle M and the following vehicle M2, the lane change determination unit 150 determines that a lane change is possible. On the other hand, when the inter-vehicle distance between the host vehicle M and the following vehicle M2 is less than the minimum inter-vehicle distance corresponding to the relative speed between the host vehicle M and the following vehicle M2, the lane change determination unit 150 determines that a lane change is not possible.

[0070] As an example, in the present embodiment, when the relative speed between the host vehicle M and the following vehicle M2 is ΔV1, the minimum inter-vehicle distance at which a lane change can be executed is set to d1. Therefore, when there is a following vehicle M2 traveling in the adjacent lane L2 when a lane change request is made and the relative speed between the host vehicle M and the following vehicle M2 is ΔV1, the lane change determination unit 150 determines that a lane change is possible if the inter-vehicle distance between the host vehicle M and the following vehicle M2 is d1 or more.

[0071] Therefore, in the present embodiment, as shown in FIG. 7(a), when the relative speed between the host vehicle M and the following vehicle M2 is ΔV1 and the inter-vehicle distance between the host vehicle M and the following vehicle M2 is d1 or more, in response to the lane change request, the control device 100 (for example, the travel control unit 170) executes a lane change to the adjacent lane L2.

[0072] As another example, in the present embodiment, when the relative speed between the host vehicle M and the following vehicle M2 is ΔV2 (where ΔV2 < ΔV1), the minimum inter-vehicle distance at which a lane change can be executed is set to d2 (where d2 < d1). Therefore, when there is a following vehicle M2 traveling in the adjacent lane L2 when a lane change request is made, and the relative speed between the host vehicle M and the following vehicle M2 is ΔV2, the lane change determination unit 150 determines that a lane change is possible if the inter-vehicle distance between the host vehicle M and the following vehicle M2 is d2 or more.

[0073] Therefore, in the present embodiment, as shown in FIG. 7(b), when the relative speed between the host vehicle M and the following vehicle M2 is ΔV2 and the inter-vehicle distance between the host vehicle M and the following vehicle M2 is d2 or more, in response to the lane change request, the control device 100 (for example, the travel control unit 170) executes a lane change to the adjacent lane L2.

[0074] Thus, in the present embodiment, the smaller the relative speed between the host vehicle M and the following vehicle M2, the more relaxed the inter-vehicle distance condition for determining whether a lane change is possible becomes. By doing so, when the relative speed between the host vehicle M and the following vehicle M2 is small and it is difficult for the inter-vehicle distance between the host vehicle M and the following vehicle M2 to decrease during a lane change (that is, when the possibility of the host vehicle M colliding with the following vehicle M2 is low), it is possible to make it easier to execute a lane change in response to the driver's lane change request.

[0075] On the other hand, if configured as described above, when the relative speed between the host vehicle M and the following vehicle M2 is large, it may be difficult to execute a lane change even if there is a driver's lane change request. For example, as described above, when there is a preceding vehicle M1 traveling at a low speed in front of the host vehicle M during ACC execution, the host vehicle M may also travel at a low speed due to the influence of the preceding vehicle M1. In such a case, the relative speed between the host vehicle M and the following vehicle M2 may become large, and there is a risk that it may be difficult to execute a lane change even if there is a driver's lane change request. From the perspective of the marketability of the host vehicle M, it is desirable to execute a lane change along with the driver's wish as much as possible when the safety of the host vehicle M can be ensured.

[0076] Therefore, when the lane change determination unit 150 is executing driving speed control (i.e., AAC), it determines whether a lane change is possible based on the relative speed with another vehicle (for example, a following vehicle M2 traveling in the adjacent lane L2 in the lane change destination) when the target speed is the driving speed of the host vehicle M. As a result, it is possible to appropriately determine whether a lane change is possible in consideration of the acceleration based on the target speed that becomes possible with the lane change, and it is possible to increase the opportunity to execute the lane change while ensuring the safety of the host vehicle M.

[0077] For example, assume that a lane change request has been made while the ACC with a target speed set to 100 [km / h] is being executed and the host vehicle M is traveling at 85 [km / h]. Also, assume that at this time, there is a following vehicle M2 traveling at 115 [km / h] in the adjacent lane L2 in the lane change destination. In such a situation, if the current speed of the host vehicle M (i.e., 85 [km / h]) is used to calculate the relative speed between the host vehicle M and the following vehicle M2, the relative speed between the host vehicle M and the following vehicle M2 will be 30 [km / h].

[0078] On the other hand, if the target speed (i.e., 100 [km / h]) is used to calculate the relative speed between the host vehicle M and the following vehicle M2, the relative speed between the host vehicle M and the following vehicle M2 will be 15 [km / h]. Therefore, by using the target speed to calculate the relative speed between the host vehicle M and the following vehicle M2, the calculated relative speed can be made smaller than when using the current speed of the host vehicle M, and thus, even when the inter-vehicle distance between the host vehicle M and the following vehicle M2 is short, it is possible to make it easier to execute the lane change.

[0079] As described above, when there is a lane change request from the driver while the ACC is in execution and the host vehicle M is traveling at a speed lower than the target speed, the lane change determination unit 150 calculates the relative speed with other vehicles based on the target speed of the ACC and determines whether a lane change is possible. Thereby, even when the host vehicle M is traveling at a low speed due to the influence of the preceding vehicle M1 in the host lane L1 or the like, the control device 100 can appropriately determine whether a lane change is possible in consideration of the acceleration based on the target speed that becomes possible with the lane change, and can increase the opportunity to execute the lane change while ensuring the safety of the host vehicle M. Therefore, the marketability of the host vehicle M can be improved.

[0080] <Processing executed by the control device 100> Hereinafter, a specific example of the processing executed by the control device 100 will be described with reference to FIGS. 8 to 12. The control device 100 repeatedly executes the lane change support processing shown in FIGS. 8 and 9 at a predetermined cycle, for example, when the ignition power source of the host vehicle M is on.

[0081] As shown in FIG. 8, the control device 100 first determines whether a lane change in progress flag indicating that a lane change by the control device 100 is in progress is on (step S1). If it is determined that the lane change in progress flag is on (step S1: Yes), the control device 100 proceeds to the processing of step S10 described later. On the other hand, if it is determined that the lane change in progress flag is off (step S1: No), the control device 100 determines whether there is a lane change request from the driver (step S2).

[0082] If it is determined that there is no lane change request (step S2: No), the control device 100 ends the current lane change support processing as it is. On the other hand, if it is determined that there is a lane change request (step S2: Yes), the control device 100 proceeds to the processing of the lane change possibility determination processing (step S3) for determining whether a lane change is possible.

[0083] As shown in FIG. 10, in the lane change feasibility determination process (step S3), the control device 100 first determines whether there is a following vehicle M2 in the adjacent lane L2 of the lane change destination (step S18). If it is determined that there is a following vehicle M2 in the adjacent lane L2 of the lane change destination (step S18: Yes), the control device 100 determines whether ACC is being executed (step S19).

[0084] If it is determined that ACC is being executed (step S19: Yes), the control device 100 determines whether the current speed of the host vehicle M is less than the target speed (step S20). If it is determined that the current speed of the host vehicle M is less than the target speed (step S20: Yes), the control device 100 determines whether the speed difference between the current speed of the host vehicle M and the target speed is less than a predetermined threshold (step S21). This threshold is set in advance for the control device 100 by, for example, the manufacturer of the host vehicle M or the like.

[0085] If it is determined that the speed difference between the current speed of the host vehicle M and the target speed is less than the threshold (step S21: Yes), the control device 100 determines whether there is no preceding vehicle M1 that hinders the acceleration of the host vehicle M based on the target speed in the host lane L1 or the adjacent lane L2 (step S22). Examples of the preceding vehicle M1 that hinders the acceleration of the host vehicle M based on the target speed include, for example, a preceding vehicle M1 with a distance between the host vehicle M and the preceding vehicle M1 of a predetermined value or less. Further, the preceding vehicle M1 that hinders the acceleration of the host vehicle M based on the target speed may be a preceding vehicle M1 with a distance between the host vehicle M and the preceding vehicle M1 of a predetermined value or less and a relative speed of a predetermined value (for example, a negative value) or less when the target speed is the traveling speed of the host vehicle M.

[0086] If it is determined that there is no preceding vehicle M1 that hinders the acceleration of the host vehicle M in either the host lane L1 or the adjacent lane L2 (step S22: Yes), the control device 100 calculates the relative speed between the host vehicle M and the following vehicle M2 based on the target speed (step S24). That is, in this case, the control device 100 calculates the relative speed with the following vehicle M2 when the target speed is the traveling speed of the host vehicle M.

[0087] On the other hand, when it is determined in the process of step S19 that ACC is not being executed (step S19: No), when it is determined in the process of step S20 that the current speed of the host vehicle M is equal to or higher than the target speed (step S20: No), when it is determined in the process of step S21 that the speed difference between the current speed of the host vehicle M and the target speed is equal to or higher than the threshold value (step S21: No), or when it is determined in the process of step S22 that there is a preceding vehicle M1 that obstructs the acceleration of the host vehicle M in the host lane L1 or the adjacent lane L2 (step S22: No), the control device 100 calculates the relative speed between the host vehicle M and the following vehicle M2 based on the current speed of the host vehicle M (step S23).

[0088] Next, the control device 100 calculates the inter-vehicle distance between the host vehicle M and the following vehicle M2 (step S25), and determines whether or not this inter-vehicle distance is equal to or greater than the minimum inter-vehicle distance corresponding to the relative speed calculated by the process of step S23 or step S24 (step S26).

[0089] If it is determined that the inter-vehicle distance between the host vehicle M and the following vehicle M2 is equal to or greater than the minimum inter-vehicle distance (step S26: Yes), the control device 100 determines that lane change is possible (step S27), and ends the lane change possibility determination process. On the other hand, if it is determined that the inter-vehicle distance between the host vehicle M and the following vehicle M2 is less than the minimum inter-vehicle distance (step S26: No), the control device 100 determines that lane change is not possible (step S28), and ends the lane change possibility determination process.

[0090] As described above, while ACC is being executed (step S19: Yes), when there is a following vehicle M2 in the adjacent lane L2 of the lane change destination (step S18: Yes), and when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the adjacent lane L2 (step S22: No), the control device 100 (for example, the lane change determination unit 150) determines the feasibility of lane change based on the relative speed with the following vehicle M2 according to the current speed of the host vehicle M (steps S26 to S28). Thereby, when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the adjacent lane L2, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed, and ensure the safety of the host vehicle M.

[0091] Note that while ACC is being executed, when there is a following vehicle M2 in the adjacent lane L2 of the lane change destination, and when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the adjacent lane L2, the control device 100 (for example, the lane change determination unit 150) may uniformly determine that lane change is not possible. Even in this case, when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the adjacent lane L2, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed, and ensure the safety of the host vehicle M.

[0092] Also, while ACC is being executed, when there is a following vehicle M2 in the adjacent lane L2 of the lane change destination, and when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the host lane L1 (step S22: No), the control device 100 (for example, the lane change determination unit 150) determines the feasibility of lane change based on the relative speed with the following vehicle M2 according to the current speed of the host vehicle M (steps S26 to S28). Thereby, when there is a leading vehicle M1 that obstructs acceleration based on the target speed of the host vehicle M in the host lane L1, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed, and ensure the safety of the host vehicle M.

[0093] Incidentally, when ACC is in execution, there is a following vehicle M2 in the adjacent lane L2 to the lane change destination, and there is a preceding vehicle M1 in the own lane L1 that hinders acceleration based on the target speed of the own vehicle M, the control device 100 (for example, the lane change determination unit 150) may uniformly determine that lane change is not possible. Even in this case, when there is a preceding vehicle M1 in the own lane L1 that hinders acceleration based on the target speed of the own vehicle M, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed and ensure the safety of the own vehicle M.

[0094] Also, when ACC is in execution (step S19: Yes), the current speed of the own vehicle M is less than the target speed (step S20: Yes), and further when the speed difference between the current speed and the target speed of the own vehicle M is equal to or greater than a predetermined threshold (step S21: No), the control device 100 (for example, the lane change determination unit 150) determines whether or not to change lanes based on the relative speed with the following vehicle M2 according to the current speed of the own vehicle M (steps S26 to S28). Thereby, it is possible to suppress a lane change in which rapid acceleration may occur. That is, when the speed difference between the current speed and the target speed of the own vehicle M is equal to or greater than the threshold value, if a lane change accompanied by acceleration based on the target speed is executed, the acceleration at the time of the lane change becomes excessive and rapid acceleration may be performed at the time of the lane change. If rapid acceleration is performed at the time of lane change, it may make the driver of the own vehicle M feel uneasy or lead to deterioration of the NV (Noise, Vibration) characteristics of the own vehicle M.

[0095] Therefore, as described above, when the speed difference between the current speed and the target speed of the own vehicle M is equal to or greater than the threshold value, the control device 100 determines whether or not to change lanes based on the relative speed with the following vehicle M2 according to the current speed of the own vehicle M, and permits the execution of a lane change only when the lane change can be executed without performing acceleration based on the target speed. Thereby, it is possible to suppress the execution of a lane change in which rapid acceleration may occur, avoid making the driver feel uneasy or deteriorating the NV characteristics of the own vehicle M, and improve the marketability of the own vehicle M.

[0096] Incidentally, while the ACC is being executed, if the current speed of the host vehicle M is less than the target speed and the speed difference between the current speed and the target speed of the host vehicle M is equal to or greater than a predetermined threshold value, the control device 100 (for example, the lane change determination unit 150) may be configured to uniformly determine that lane change is not possible. Even in this case, it is possible to suppress the execution of a lane change that may cause sudden acceleration, avoid disturbing the driver or deteriorating the NV characteristics of the host vehicle M, and improve the marketability of the host vehicle M.

[0097] Further, in the process of step S18, if it is determined that there is no following vehicle M2 in the adjacent lane L2 of the lane change destination (step S18: No), as shown in FIG. 11, the control device 100 determines whether there is a preceding vehicle M1 in the adjacent lane L2 of the lane change destination (step S29).

[0098] If it is determined that there is no preceding vehicle M1 in the adjacent lane L2 of the lane change destination (step S29: No), the control device 100 proceeds to the process of step S33. On the other hand, if it is determined that there is a preceding vehicle M1 in the adjacent lane L2 of the lane change destination (step S29: Yes), the control device 100 calculates the relative speed between the host vehicle M and the preceding vehicle M1 (step S30). For example, the current speed of the host vehicle M is used to calculate the relative speed between the host vehicle M and the preceding vehicle M1. Also, if the ACC is being executed, the target speed may be used to calculate the relative speed between the host vehicle M and the preceding vehicle M1.

[0099] Next, the control device 100 calculates the inter-vehicle distance between the host vehicle M and the preceding vehicle M1 (step S31), and determines whether this inter-vehicle distance is equal to or greater than the minimum inter-vehicle distance corresponding to the relative speed calculated in the process of step S30 (step S32).

[0100] If it is determined that the inter-vehicle distance between the host vehicle M and the preceding vehicle M1 is equal to or greater than the minimum inter-vehicle distance (step S32: Yes), the control device 100 determines that lane change is possible (step S33) and ends the lane change determination process. On the other hand, if it is determined that the inter-vehicle distance between the host vehicle M and the preceding vehicle M1 is less than the minimum inter-vehicle distance (step S32: No), the control device 100 determines that lane change is not possible (step S34) and ends the lane change determination process.

[0101] After executing the lane change determination process (step S3) shown in FIGS. 10 and 11, the control device 100 determines whether or not the determination result of the lane change determination process indicates that lane change is possible, as shown in FIG. 8 (step S4). If the determination result of the lane change determination process indicates that lane change is not possible (step S4: No), the control device 100 ends the current lane change support process as it is.

[0102] On the other hand, if the determination result of the lane change determination process indicates that lane change is possible (step S4: Yes), the control device 100 turns on the lane change in progress flag (step S5) and starts turning on the blinker 83 (step S6).

[0103] Next, the control device 100 determines whether or not ACC is being executed (step S7). If it is determined that ACC is not being executed (step S7: No), the control device 100 proceeds to the process of step S10 described later. If it is determined that ACC is being executed (step S7: Yes), the control device 100 determines whether or not the current speed of the host vehicle M is less than the target speed (step S8).

[0104] If it is determined that the current speed of the host vehicle M is not less than the target speed (step S8: No), the control device 100 proceeds to the process of step S10 described later. If it is determined that the current speed of the host vehicle M is less than the target speed (step S8: Yes), the control device 100 starts acceleration based on the target speed (step S9).

[0105] Next, the control device 100 determines whether it is the lateral movement start timing (step S10). If it is determined that it is not the lateral movement start timing (step S10: No), the control device 100 directly proceeds to the process of step S12 described later. On the other hand, if it is determined that it is the lateral movement start timing (step S10: Yes), the control device 100 starts the lateral movement (step S11) and proceeds to the process of step S12.

[0106] Next, as shown in FIG. 9, the control device 100 determines whether the host vehicle M has reached before the dividing line C at the boundary between the own lane L1 and the adjacent lane L2 of the lane change destination (step S12). If the host vehicle M has reached the dividing line C (step S12: No), the control device 100 directly proceeds to the process of step S15 described later. On the other hand, if the host vehicle M has not yet reached the dividing line C (step S12: Yes), the control device 100 executes the lane change cancellation determination process shown in FIG. 12 (step S13).

[0107] As shown in FIG. 12, in the lane change cancellation determination process (step S13), the control device 100 first determines whether there is another vehicle (for example, the following vehicle M2) in the adjacent lane L2 of the lane change destination (step S35). If it is determined that there is no other vehicle in the adjacent lane L2 of the lane change destination (step S35: No), the control device 100 directly ends the lane change cancellation determination process.

[0108] On the other hand, if it is determined that there is another vehicle in the adjacent lane L2 of the lane change destination (step S35: Yes), the control device 100 calculates the relative speed between the host vehicle M and the other vehicle existing in the adjacent lane L2 (step S36). For example, the current speed of the host vehicle M is used to calculate the relative speed between the host vehicle M and the other vehicle.

[0109] Next, the control device 100 calculates the inter-vehicle distance between the host vehicle M and the other vehicle existing in the adjacent lane L2 (step S37), and determines whether this inter-vehicle distance is equal to or less than a threshold value that is the cancellation condition for the lane change (step S38).

[0110] If it is determined that the inter-vehicle distance between the host vehicle M and another vehicle present in the adjacent lane L2 is not less than the threshold value that is the condition for canceling the lane change (step S38: No), the control device 100 ends the lane change cancellation determination process as it is.

[0111] On the other hand, if it is determined that the inter-vehicle distance between the host vehicle M and another vehicle present in the adjacent lane L2 is less than or equal to the threshold value that is the condition for canceling the lane change (step S38: Yes), the control device 100 cancels the lane change and returns the host vehicle M to the center of the host lane L1 (step S39).

[0112] Then, the control device 100 notifies the driver that the lane change has been canceled (step S40), turns off the lane change in progress flag (step S41), and ends the lane change cancellation determination process.

[0113] In this way, before the host vehicle M reaches the lane dividing line C, that is, before the host vehicle M deviates from the host lane L1, if the inter-vehicle distance between the host vehicle M and another vehicle (for example, the following vehicle M2) traveling in the adjacent lane L2 becomes short, the control device 100 can ensure the safety of the host vehicle M by canceling the lane change.

[0114] After executing the lane change cancellation determination process (step S13) shown in FIG. 12, the control device 100 determines whether the lane change in progress flag is on as shown in FIG. 8 (step S14). If it is determined that the lane change in progress flag is off (step S14: No), the control device 100 ends the current lane change support process as it is.

[0115] On the one hand, if it is determined that the lane change flag is on (step S14: Yes), the control device 100 determines whether the movement to the adjacent lane L2 of the lane change destination has been completed (step S15). If it is determined that the movement to the adjacent lane L2 has been completed (step S15: Yes), the control device 100 turns off the turn signal 83 (step S16), turns off the lane change flag (step S17), and ends the current lane change support process. On the other hand, if it is determined that the movement to the adjacent lane L2 has not been completed (step S15: No), the control device 100 simply ends the current lane change support process.

[0116] As described above, according to the present embodiment, during the execution of the traveling speed control (i.e., ACC), it is possible to determine the feasibility of a lane change based on the relative speed with another vehicle (e.g., the following vehicle M2) when the target speed is the traveling speed of the host vehicle M. Thereby, even when the host vehicle M is traveling at a low speed due to the influence of the preceding vehicle M1 in the host lane L1, etc., it is possible to appropriately determine the feasibility of a lane change in consideration of the acceleration based on the target speed that becomes possible with the lane change, and it is possible to increase the opportunity to execute a lane change while ensuring the safety of the host vehicle M.

[0117] As described above, one embodiment of the present invention has been described with reference to the drawings. Needless to say, the present invention is not limited to the above-described embodiment. It is obvious that those skilled in the art can conceive of various modification examples or correction examples within the scope described in the claims, and it is naturally understood that they also belong to the technical scope of the present invention. Also, within the scope not departing from the gist of the invention, the components in the above-described embodiment may be arbitrarily combined.

[0118] For example, in the above-described embodiment, an example was described in which a predetermined operation as a lane change request was a half-lock operation of the turn signal lever 81, but the present invention is not limited thereto. The predetermined operation as a lane change request is not limited to the half-lock operation of the turn signal lever 81, and can be an arbitrary operation on various operators. As an example, an auto lane change button may be provided on the steering wheel 82, and the predetermined operation as a lane change request may be pressing of this button.

[0119] Further, while the control device 100 was described as proposing to the driver to execute a lane change based on the speed difference between the current speed and the target speed of the host vehicle M during ACC execution, the present invention is not limited thereto. For example, during ACC execution, when the current speed of the host vehicle M is less than the target speed and the speed difference between the current speed and the target speed of the host vehicle M is equal to or greater than a predetermined threshold value, it is assumed that the host vehicle M is traveling at a low speed due to the influence of the preceding vehicle M1 or the like. Therefore, during ACC execution, when the current speed of the host vehicle M is less than the target speed and the speed difference between the current speed and the target speed of the host vehicle M is equal to or greater than the threshold value, the control device 100 may propose to the driver to execute a lane change so as to enable traveling at the target speed. By doing so, it is possible to prompt the driver to perform an appropriate lane change, improve the convenience of the driver, and improve the marketability of the host vehicle M.

[0120] Further, in the above-described embodiment, the control device 100 was described as executing a lane change when there is a lane change request from the driver, but the present invention is not limited thereto. For example, regardless of whether there is a lane change request from the driver, the control device 100 appropriately determines the necessity of a lane change based on the traveling situation of other vehicles, the route to the destination, and the like, and when it is determined that a lane change is necessary, the control device 100 may automatically execute the lane change.

[0121] More specifically, for example, when the ACC is in execution and a preceding vehicle M1 traveling at a speed lower than the target speed of the host vehicle M is present in the host lane L1, the control device 100 may automatically execute a lane change. As a specific example, during the execution of ACC, when the current speed of the host vehicle M is less than the target speed and the speed difference between the current speed of the host vehicle M and the target speed is equal to or greater than a threshold value, the control device 100 may automatically execute a lane change to enable traveling at the target speed. Also, even when configured to be able to automatically execute a lane change during the execution of ACC, if a following vehicle M2 is present in the adjacent lane L2, the control device 100 may determine the feasibility of the lane change based on the relative speed with the following vehicle M2 when the target speed is set as the traveling speed of the host vehicle M. By configuring the control device 100 to be able to automatically execute a lane change in this way, an appropriate lane change can be automatically executed, improving the convenience for the driver and enhancing the marketability of the host vehicle M.

[0122] Also, when automatically executing a lane change, the control device 100 may notify the driver that the lane change is to be executed. In this way, it is possible to avoid a situation where the lane change is executed without notice, giving the driver a sense of unease or discomfort.

[0123] At least the following matters are described in this specification and the like. Although the corresponding components and the like in the foregoing embodiments are shown in parentheses, the present invention is not limited thereto.

[0124] (1) A lane change support device (control device 100) capable of executing a lane change of the host vehicle from the host lane (host lane L1) in which the host vehicle (host vehicle M) is traveling to an adjacent lane (adjacent lane L2) adjacent to the host lane, a recognition unit (recognition unit 130) that recognizes the surrounding situation of the host vehicle; a lane change determination unit (lane change determination unit 150) that determines the feasibility of the lane change based on the relative speed between the host vehicle and the other vehicle and the inter-vehicle distance between the host vehicle and the other vehicle when the other vehicle traveling in the adjacent lane is detected by the recognition unit; Based on the determination result of the lane change determination unit, a driving control unit (driving control unit 170) capable of executing the lane change, and comprising the driving control unit is further capable of executing driving speed control (ACC) for controlling the driving speed of the host vehicle based on a preset target speed, when the driving speed control is being executed, the lane change determination unit determines the feasibility of the lane change based on the relative speed when the target speed is the driving speed of the host vehicle, a lane change assistance device.

[0125] (1) According to this, even when the host vehicle is driving at a low speed due to the influence of the preceding vehicle in the own lane, etc., it is possible to appropriately determine the feasibility of the lane change in consideration of the acceleration based on the target speed that becomes possible with the lane change, and it is possible to increase the opportunity to execute the lane change while ensuring the safety of the host vehicle.

[0126] (2) The lane change assistance device according to (1), wherein the other vehicle is a following vehicle traveling behind the host vehicle, a lane change assistance device.

[0127] (2) According to this, even when there is a following vehicle traveling in the adjacent lane, it is possible to appropriately determine the feasibility of the lane change.

[0128] (3) The lane change assistance device according to (2), wherein when there is no preceding vehicle traveling in front of the host vehicle, the driving speed control makes the driving speed of the host vehicle reach the target speed, and when the preceding vehicle exists in the own lane, the driving speed control adjusts the driving speed of the host vehicle according to the driving speed of the preceding vehicle, a lane change assistance device.

[0129] According to (3), by controlling the traveling speed, the traveling speed of the host vehicle can be appropriately controlled in consideration of the presence or absence of the preceding vehicle in the host lane and its traveling speed. Therefore, while ensuring the safety of the host vehicle, it is possible to reduce the fatigue of the driver of the host vehicle and the like.

[0130] (4) The lane change support device according to (3), When the traveling control unit executes the lane change during the execution of the traveling speed control, the traveling control unit accelerates the host vehicle based on the target speed before the movement of the host vehicle to the adjacent lane due to the lane change is completed. Lane change support device.

[0131] (4) According to this, since the host vehicle is accelerated based on the target speed before the movement of the host vehicle to the adjacent lane due to the lane change is completed, it is possible to suppress the reduction of the distance between the host vehicle and the following vehicle traveling in the adjacent lane, and execute the lane change while ensuring the safety of the host vehicle.

[0132] (5) The lane change support device according to (4), When the traveling control unit executes the lane change during the execution of the traveling speed control, the traveling control unit accelerates the host vehicle to the target speed before the movement of the host vehicle to the adjacent lane due to the lane change is completed. Lane change support device.

[0133] (5) According to this, since the host vehicle is accelerated to the target speed before the movement of the host vehicle to the adjacent lane due to the lane change is completed, it is possible to suppress the reduction of the distance between the host vehicle and the following vehicle traveling in the adjacent lane, and execute the lane change while ensuring the safety of the host vehicle.

[0134] (6) The lane change support device according to any one of (3) to (5), When the lane change determination unit determines that the traveling speed control is being executed and there is a preceding vehicle in the adjacent lane that hinders the acceleration of the host vehicle based on the target speed of the host vehicle, the lane change determination unit determines not to execute the lane change. Lane change support device.

[0135] (6) According to this, when a preceding vehicle that hinders the acceleration of the host vehicle exists in an adjacent lane, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed and ensure the safety of the host vehicle.

[0136] (7) A lane change support device according to any one of (3) to (6), wherein when the travel speed control is being executed and a preceding vehicle that hinders the acceleration of the host vehicle based on the target speed of the host vehicle further exists in the host lane, the lane change determination unit determines not to execute the lane change. Lane change support device.

[0137] (7) According to this, when a preceding vehicle that hinders the acceleration of the host vehicle exists in the host lane, it is possible to suppress the execution of a lane change accompanied by acceleration based on the target speed and ensure the safety of the host vehicle.

[0138] (8) A lane change support device according to any one of (3) to (7), wherein when the travel speed control is being executed and the speed difference between the current travel speed of the host vehicle and the target speed is greater than or equal to a threshold value, the lane change determination unit determines not to execute the lane change. Lane change support device.

[0139] When a sudden acceleration is performed during a lane change, there is a possibility that the driver of the host vehicle may be made uneasy or that the NV (Noise, Vibration) characteristics of the host vehicle may deteriorate. According to (8), it is possible to suppress the execution of a lane change in which a sudden acceleration may occur, avoid making the driver of the host vehicle uneasy or deteriorating the NV characteristics of the host vehicle, and improve the marketability of the host vehicle.

[0140] (9) A lane change support device according to any one of (3) to (8), the lane change support device, When the traveling speed control is being executed and the leading vehicle is present in the own lane, a notification control unit (notification control unit 167) is further provided that proposes the lane change to the driver of the own vehicle based on the speed difference between the current traveling speed of the own vehicle and the target speed. Lane change support device.

[0141] (9) According to this, it is possible to prompt the driver to make an appropriate lane change, improve the convenience of the driver, and improve the marketability of the own vehicle.

[0142] (10) A lane change support device according to any one of (1) to (9), wherein the lane change determination unit determines the feasibility of the lane change when there is a lane change request from the driver of the own vehicle. Lane change support device.

[0143] (10) According to this, it is possible to avoid the execution of a lane change against the will of the driver.

[0144] (11) A lane change support device according to (10), wherein the lane change request is a predetermined operation on the turn signal lever (turn signal lever 81) of the own vehicle, the positions where the turn signal lever is movable are a neutral position, a first position that is in each of two different directions with respect to the neutral position and returns to the neutral position when there is no operating force applied to the turn signal lever by the driver, and a second position that is in each of two directions with respect to the neutral position, has a movement amount from the neutral position larger than that of the first position, and can maintain the position when there is no operating force applied to the turn signal lever by the driver, and the predetermined operation is an operation of maintaining the turn signal lever at the first position. Lane change support device.

[0145] According to (11), it is possible to receive a lane change request without providing an operation button or the like for receiving a lane change request separately from the turn signal lever.

[0146] (12) A lane change assistance device according to any one of (1) to (11), wherein, during the execution of the lane change and before the host vehicle reaches the dividing line that demarcates the host lane and the adjacent lane, when the inter-vehicle distance becomes equal to or less than a threshold value, the running control unit aborts the lane change. Lane change assistance device.

[0147] (12) According to this, before the host vehicle reaches the dividing line (that is, before the host vehicle deviates from the host lane), if the inter-vehicle distance between the host vehicle and a following vehicle traveling in the adjacent lane becomes short, the lane change is aborted, thereby ensuring the safety of the host vehicle.

Description of Signs

[0148] 81 Turn signal lever 100 Control device (lane change assistance device) 130 Recognition unit 150 Lane change determination unit 170 Running control unit 167 Notification control unit L1 Host lane L2 Adjacent lane M Host vehicle M1 Leading vehicle (other vehicle) M2 Following vehicle (other vehicle)

Claims

1. A lane change support device capable of executing a lane change of the host vehicle from a lane in which the host vehicle is traveling to an adjacent lane adjacent to the lane, a recognition unit that recognizes the surrounding situation of the host vehicle; a lane change determination unit that determines whether the lane change is possible based on a relative speed between the host vehicle and the other vehicle and a distance between the host vehicle and the other vehicle when the other vehicle traveling in the adjacent lane is detected by the recognition unit; a travel control unit capable of executing a lane change based on a determination result of the lane change determination unit; comprising: the travel control unit is further capable of executing travel speed control for controlling the travel speed of the host vehicle based on a preset target speed; the lane change determination unit determines whether the lane change is possible based on the relative speed when the target speed is the travel speed of the host vehicle when the travel speed control is being executed; A lane change support device.

2. The lane change support device according to claim 1, wherein the other vehicle is a following vehicle traveling behind the host vehicle. A lane change support device.

3. The lane change support device according to claim 2, wherein the travel speed control is such that when there is no leading vehicle traveling in front of the host vehicle in the lane, the travel speed of the host vehicle becomes the target speed, and when the leading vehicle exists in the lane, the travel speed of the host vehicle is adjusted according to the travel speed of the leading vehicle. A lane change support device.

4. The lane change support device according to claim 3, wherein when the travel control unit executes the lane change during the execution of the travel speed control, the travel control unit accelerates the host vehicle based on the target speed before the movement of the host vehicle to the adjacent lane due to the lane change is completed. Lane change support device.

5. The lane change support device according to claim 4, when the travel control unit executes the lane change during the execution of the travel speed control, the travel control unit accelerates the host vehicle to the target speed before the movement to the adjacent lane due to the lane change is completed. Lane change support device.

6. The lane change support device according to any one of claims 3 to 5, when the lane change determination unit determines that the travel speed control is being executed and there is still a preceding vehicle in the adjacent lane that obstructs the acceleration based on the target speed of the host vehicle, the lane change determination unit determines not to execute the lane change. Lane change support device.

7. The lane change support device according to any one of claims 3 to 6, when the lane change determination unit determines that the travel speed control is being executed and there is still a preceding vehicle in the host lane that obstructs the acceleration based on the target speed of the host vehicle, the lane change determination unit determines not to execute the lane change. Lane change support device.

8. The lane change support device according to any one of claims 3 to 7, when the lane change determination unit determines that the travel speed control is being executed and the speed difference between the current travel speed of the host vehicle and the target speed is equal to or greater than a threshold value, the lane change determination unit determines not to execute the lane change. Lane change support device.

9. The lane change support device according to any one of claims 3 to 8, the lane change support device further includes a notification control unit that proposes the lane change to the driver of the host vehicle based on the speed difference between the current travel speed of the host vehicle and the target speed when the travel speed control is being executed and the preceding vehicle is in the host lane. Lane change assistance device.

10. The lane change assistance device according to any one of claims 1 to 9, wherein the lane change determination unit determines whether the lane change is possible when there is a lane change request from the driver of the host vehicle. Lane change assistance device.

11. The lane change assistance device according to claim 10, wherein the lane change request is a predetermined operation on the turn signal lever of the host vehicle, and the positions where the turn signal lever can move are a neutral position, a first position that is in each of two different directions with respect to the neutral position and returns to the neutral position when there is no operating force on the turn signal lever by the driver, and a second position that is in each of two directions with respect to the neutral position, has a movement amount from the neutral position larger than that of the first position, and can maintain the position when there is no operating force on the turn signal lever by the driver, and the predetermined operation is an operation of maintaining the turn signal lever at the first position. Lane change assistance device.

12. The lane change assistance device according to any one of claims 1 to 11, wherein the travel control unit aborts the lane change when the inter-vehicle distance becomes less than or equal to a threshold value during the execution of the lane change and before the host vehicle reaches the dividing line that demarcates the host lane and the adjacent lane. Lane change assistance device.

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