Patent Publication Number: US-2022234586-A1

Title: Vehicle control apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority from Japanese Patent Application No. 2021-009148 filed on Jan. 22, 2021, the entire content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a vehicle control apparatus. 
     BACKGROUND ART 
     As a function of automatic driving and driving assistance of a vehicle, a function has been developed in which a vehicle performs a lane change without an operation of a driver. For example, JP-A-2018-103767 discloses a lane change assistance apparatus configured to, based on an operation of a turn signal lever by a driver, start lane change assistance control when the turn signal lever is held at a first operation position for a predetermined time or more, and stop the lane change assistance control when the turn signal lever is operated to a second operation position. The turn signal lever of the assistance apparatus is configured to be selectively operable, in a clockwise operation direction and a counterclockwise operation direction, between the first operation position where the turn signal lever is rotated by a first stroke from a neutral position and the second operation position where the turn signal lever is rotated by a second stroke deeper than the first operation position from the neutral position. 
     However, in the lane change assistance apparatus of JP-A-2018-103767, when receiving assistance control of the lane change, the turn signal lever needs to be held at the first operation position for a predetermined time or more, between the first operation position and the second operation position that are the operation positions of the turn signal lever. Further, in accordance with a direction in which a lane is changed (a left lane change or a right lane change), an operation direction (a counterclockwise operation or a clockwise operation) of the turn signal lever needs to be changed. Therefore, the operation for receiving the assistance control of the lane change is not necessarily a simple turn signal lever operation, and there is room for improvement in a content of the operation. 
     SUMMARY 
     An object of the present invention is to provide a vehicle control apparatus that can facilitate an operation of a lane change. 
     According to an aspect of the present invention, there is provided a vehicle control apparatus includes a recognition unit configured to recognize an environment in a vicinity of a vehicle; and a traveling control unit configured to execute a lane change of the vehicle based. on a recognition result by the recognition unit. The traveling control unit selectively executes a lane change of the vehicle based on proposal information of a lane change output to a driver of the vehicle by the traveling control unit and a lane change of the vehicle not based on the proposal information in response to a first operation of the same content by the driver. 
     According to the present invention, it is possible to facilitate an operation of a lane change. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram showing a configuration of a vehicle system on which a vehicle control apparatus is mounted. 
         FIG. 2  is a diagram showing a first control unit, a second control unit, and a traveling control unit of the vehicle control apparatus. 
         FIG. 3  is a table showing an example of a correspondence relationship among a driving mode, a control state of a host vehicle, and a task. 
         FIG. 4  is a diagram showing an example of a road on which the host vehicle travels. 
         FIG. 5  is a flowchart showing an example of a processing performed by a traveling control unit. 
         FIG. 6  is a diagram showing examples of lane change buttons provided on a steering wheel. 
         FIG. 7  is a diagram showing an example of a road for illustrating a proposed automatic lane change (overtaking). 
         FIG. 8  is a flowchart showing an example of a processing of the proposed automatic lane change (the overtaking). 
         FIG. 9  is a diagram showing an example of a road for illustrating a proposed automatic lane change (yield). 
         FIG. 10  is a flowchart showing an example of a processing of the proposed automatic lane change (the yield). 
         FIG. 11  is a diagram showing an example of a road for illustrating an intended automatic lane change. 
         FIG. 12  is a flowchart showing an example of a processing of the intended automatic lane change. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 
     [Overall Configuration] 
       FIG. 1  is a block diagram showing a configuration of a vehicle system  1  on which a vehicle control apparatus of the embodiment is mounted. A vehicle on which the vehicle system  1  is mounted is, for example, a vehicle such as a two-wheeled vehicle, a three-wheeled vehicle, or a four-wheeled vehicle, and a driving source of the vehicle 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 electric power generated by a generator connected to the internal combustion engine or electric power discharged from a secondary battery or a fuel cell. 
     The vehicle system  1  includes, for example, a camera  10 , a radar apparatus  12 , light detection and ranging (LIDAR)  14 , an object recognition apparatus  16 , a communication apparatus  20 , a human machine interface (HMI)  30 , a vehicle sensor  40 , a driver monitor camera  50 , a navigation apparatus  60 , a map positioning unit (MPU)  70 , a driving operator  80 , a vehicle control apparatus  100 , a traveling driving force output apparatus  200 , a brake apparatus  210 , and a steering apparatus  220 . These apparatuses and devices are connected to one another by a multiplex communication line such as a controller area network (CAN) communication line, a serial communication line, a wireless communication network, or the like. 
     The camera  10  is, for example, a digital camera that uses a solid-state image-capturing element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The camera  10  is attached to an optional place of the vehicle (hereinafter, referred to as host vehicle M) on which the vehicle system  1  is mounted. 
     The radar apparatus  12  radiates radio waves such as millimeter waves to a vicinity of the host vehicle M, and detects radio waves reflected by an object (reflected waves) to detect at least a position (a distance and an orientation) of the object. The radar apparatus  12  is attached to an optional place of the host vehicle M. 
     The LIDAR  14  emits light (or an electromagnetic wave having a wavelength close to that of the light) to the vicinity of the host vehicle M and measures scattered light. The LIDAR  14  detects a distance from a target based on time from light emission to light reception. The emitted light is, for example, pulsed laser light. The LIDAR  14  is attached to an optional place of the host vehicle M. 
     The object recognition apparatus  16  performs a sensor fusion processing on detection results of some or all of the camera  10 , the radar apparatus  12 , and the LIDAR  14  to recognize a position, a type, a speed, and the like of an object. The object recognition apparatus  16  outputs a recognition result to the vehicle control apparatus  100 . The object recognition apparatus  16  may output the detection results of the camera  10 , the radar apparatus  12 , and the LIDAR  14  to the vehicle control apparatus  100  as they are. 
     The communication apparatus  20  communicates with other vehicles present in the vicinity of the host vehicle M by using, for example, a cellular network, a Wi-Fi (registered trademark) network, a Bluetooth (registered trademark), dedicated short range communication (DSRC), or the like, or communicates with various server apparatuses via a wireless base station. 
     The HMI  30  presents various pieces of information to an occupant of the host vehicle M and receives an input operation by the occupant. The HMI  30  includes various display apparatuses, speakers, buzzers, touch panels, switches, keys, and the like. 
     The vehicle sensor  40  includes a vehicle speed sensor that detects a speed of the host vehicle M, an acceleration sensor that detects an acceleration, a yaw rate sensor that detects an angular speed around a vertical axis, an orientation sensor that detects a direction of the host vehicle M, and the like. 
     The driver monitor camera  50  is, for example, a digital camera that uses a solid-state image-capturing element such as a CCD or a CMOS. The driver monitor camera  50  is attached to an optional place of the host vehicle M at a position and in a direction where an image of a head of an occupant (hereinafter, referred to as driver) seated in a driver seat of the host vehicle M can be captured from a front (in a direction in which an image of a face is captured). 
     The navigation apparatus  60  includes, for example, a global navigation satellite system (GNSS) receiver  61 , a navigation HMI  62 , and a route determination unit  63 . The navigation apparatus  60  stores first map information  64  in a storage apparatus such as a hard disk drive (HDD) or a flash memory. 
     The GNSS receiver  61  identifies a position of the host vehicle M based on a signal received from a GNSS satellite. The position of the host vehicle M may be identified or complemented by an inertial navigation system (INS) that uses an output of the vehicle sensor  40 . 
     The navigation HMI  62  includes a display apparatus, a speaker, a touch panel, a key, and the like. The navigation HMI  62  may be partially or entirely shared with the HMI  30  described above. 
     For example, the route determination unit  63  determines, with reference to the first map information  64 , a route (hereinafter, referred to as on-map route) from a position of the host vehicle M identified by the GNSS receiver  61  (or an input optional position) to a destination input by the occupant by using the navigation HMI  62 . The first map information  64  is, for example, information in which a road shape is represented by a link indicating a road and a node connected by the link. The first map information  64  may include a curvature of a road, point of interest (POI) information, and the like. The on-map route is output to the MPU  70 . 
     The navigation apparatus  60  may perform route guidance that uses the navigation HMI  62  based on the on-map route. The navigation apparatus  60  may transmit a current position and a destination to a navigation server via the communication apparatus  20  and acquire a route equivalent to the on-map route from the navigation server. 
     The MPU  70  includes, for example, a recommended lane determination unit  71 , and stores second map information  72  in a storage apparatus such as an HDD or a flash memory. The recommended lane determination unit  71  divides the on-map route provided from the navigation apparatus  60  into a plurality of blocks (for example, divides the on-map route every 100 [m] in a vehicle traveling direction), and determines a recommended lane for each block with reference to the second map information  72 . For example, the recommended lane determination unit  71  determines which lane from a left the vehicle travels in. When there is a branching place on the on-map route, the recommended lane determination unit  71  determines a recommended lane such that the host vehicle M can travel on a reasonable route for traveling to a branch destination. 
     The second map information  72  is map information having accuracy higher than that of the first map information  64 . The second map information  72  includes, for example, information on a center of a lane, information on a boundary of the lane, or the like. 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 as needed by the communication apparatus  20  communicating with another apparatus. 
     The driving operator  80  includes, for example, an accelerator pedal, a brake pedal, a shift lever, and other operators in addition to a steering wheel  82  (an example of a steering apparatus). A sensor that detects an operation amount or presence or absence of an operation is attached to the driving operator  80 , and a detection result thereof is output to the vehicle control apparatus  100  or some or all of the traveling driving force output apparatus  200 , the brake apparatus  210 , and the steering apparatus  220 . The steering wheel  82  does not necessarily have to be annular, and may be in a form of an irregularly shaped steering member, a joystick, a button, or the like. 
     A steering grip sensor  84  is attached to the steering wheel  82 . The steering grip sensor  84  is implemented by an electrostatic capacitance sensor or the like, and outputs a signal capable of detecting whether the driver grips the steering wheel  82  to the vehicle control apparatus  100 . Further, the steering wheel  82  is provided with a lane change button  86  (an example of a pressing button). The lane change button  86  is an operator for changing a lane of the host vehicle M, and is operated by the driver. When operated, the lane change button  86  outputs a lane change signal that instructs a lane change to the vehicle control apparatus  100 . 
     The vehicle control apparatus  100  includes a first control unit  120  and a second control unit  160 . Each of the first control unit  120  and the second control unit  160  is implemented by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software). Further, some or all of these components may be implemented by hardware (including circuitry) such as large scale integration (LSI), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a graphics processing unit (GPU), or may be implemented by cooperation of software and the hardware. The program may be stored in advance in a storage apparatus such as an HDD or a flash memory of the vehicle control apparatus  100 . 
       FIG. 2  is a block diagram showing functions of the first control unit  120 , the second. control unit  160 , and a traveling control unit  170 . The first control unit  120  includes, for example, a recognition unit  130 , an action plan generation unit  140 , and a mode determination unit  150 . The first control unit  120  implements, for example, a function based on artificial intelligence (AI) and a function based on a model given in advance in parallel. For example, a function of “recognizing an intersection” may be implemented by executing recognition of the intersection based on deep learning or the like and recognition based on a condition given in advance (there is a signal, a road sign, or the like that can be subjected to pattern matching) in parallel, scoring bath of them, and comprehensively evaluating them. Accordingly, reliability of automatic driving is ensured. 
     Based on information input from the camera  10 , the radar apparatus  12 , and the LIDAR  14  via the object recognition apparatus  16 , the recognition unit  130  recognizes a position of an object in the vicinity of the host vehicle M and a traveling state such as a speed and an acceleration of the object. The position of the object is recognized as, for example, a position on absolute coordinates with a representative point (a center of gravity, a driving shaft center, or the like) of the host vehicle M as an origin, and is used for control. The position of the object may be represented by a representative point such as a center of gravity or a corner of the object, or may be represented by a region. The “state” of the object may include acceleration, a jerk, or an “action state” of the object (for example, whether the object is changing a lane or is about to change the lane). 
     Further, the recognition unit  130  recognizes, for example, a traveling environment in which the host vehicle M travels. For example, the recognition unit  130  recognizes a traveling lane of the host vehicle M by comparing a pattern of road partition lines (for example, an arrangement of solid lines and broken lines) obtained from the second map information  72  with a pattern of road partition lines in the vicinity of the host vehicle M recognized from an image captured by the camera  10 . The recognition unit  130  may recognize a traveling lane by recognizing traveling boundaries (road boundaries) including the road partition lines, road shoulders, curbstones, a median strip, guard rails, or the like, without being limited to the road partition lines. In the recognition, a position of the host vehicle M acquired from the navigation apparatus  60  or a processing result by the INS may be added. Further, the recognition unit  130  recognizes a temporary stop line, an obstacle, a red light, a toll gate, and other road events. 
     When recognizing the traveling lane, the recognition unit  130  recognizes a position and a posture of the host vehicle M with respect to the traveling lane. For example, the recognition unit  130  may recognize a deviation of a reference point of the host vehicle M from a center of the lane and an angle formed with respect to a line that connects the center of the lane in a traveling direction of the host vehicle M as a relative position and a posture of the host vehicle M with respect to the traveling lane. Alternatively, the recognition unit  130  may recognize the position of the reference point of the host vehicle M with respect to any side end portion (a road partition line or a road boundary) of the traveling lane or the like as the relative position of the host vehicle M with respect to the traveling lane. 
     In principle, the action plan generation unit  140  generates a target trajectory along which the host vehicle M travels in the future automatically (without depending on an operation of the driver) such that the host vehicle M travels in a recommended lane determined by the recommended lane determination unit  71  and can cope with a surrounding situation of the host vehicle M. The target trajectory includes, for example, a speed element. For example, the target trajectory is represented by sequentially arranging points (trajectory points) to be reached by the host vehicle M. The trajectory point is a point where the host vehicle M should arrive for each predetermined traveling distance (for example, about several [m]) at a road distance, and separately, a target speed and a target acceleration for each predetermined sampling time (for example, about 0 decimal point [sec]) are generated as a part of the target trajectory. Further, the trajectory point may be a position where the host vehicle M should arrive at a sampling time point for each predetermined sampling time. In this case, information on the target speed and the target acceleration is represented by an interval between the trajectory points. 
     When generating e target trajectory, the action plan generation unit  140  may set an event of automatic driving. Examples of the vent of the automatic driving include a constant speed traveling event, a low speed following traveling event, a lane change event, a branching event, a merging event, and a takeover event. The action plan generation unit  140  generates a target trajectory in accordance with an activated event. 
     The mode determination unit  150  determines a driving mode of the host vehicle M to be any one of a plurality of driving modes in which tasks imposed on the driver are different. Further, when a task of the determined driving mode (hereinafter, referred to as current driving mode) is not executed by the driver, the mode determination unit  150  changes the driving mode of the host vehicle M to a driving mode in which a task is heavier. 
       FIG. 3  is a table showing an example of a correspondence relationship among a driving mode, a control state of the host vehicle M, and a task. Driving modes of the host vehicle M include, for example, five modes from a first driving mode to a fifth driving mode. The control state, that is, a degree of automation of driving control of the host vehicle M is the highest in the first driving mode, then decreases in an order of the second driving mode, the third driving mode, and the fourth driving mode, and is the lowest in the fifth driving mode. On the contrary, a task imposed on the driver is the lightest in the first driving mode, then becomes heavy in an order of the second driving mode, the third driving mode, and the fourth driving mode, and is the heaviest in the fifth driving mode. In a driving mode other than the first driving mode, the vehicle control apparatus  100  is in a control state that is not automatic driving. Therefore, the vehicle control apparatus  100  is in charge of ending control of the automatic driving and shifting to driving assistance or manual driving. Hereinafter, contents of the respective driving modes will be exemplified. 
     In the first driving mode, an automatic driving state is established, and neither front monitoring nor gripping of the steering wheel  82  (steering gripping in the drawing) is imposed on the driver. However, even in the first driving mode, the driver is required to be in a posture in which the driver can quickly shift to the manual driving in response to a request from the vehicle control apparatus  100 . The “automatic driving” as used herein means that both steering and acceleration and deceleration are controlled without depending on an operation of the driver. The front means a space in the traveling direction of the host vehicle M visually recognized via a front windshield. The first driving mode is, for example, a driving mode that can be executed when a condition that the host vehicle M travels at a predetermined speed or less (for example, about 60 [km/h]) on an automobile dedicated road such as an expressway and there is a preceding vehicle to be followed is satisfied. 
     In the second driving mode, a driving assistance state is established, and a task of monitoring a front of the host vehicle M (hereinafter, referred to as front monitoring) is imposed on the driver, but a task of gripping the steering wheel  82  is not imposed on the driver. In the third driving mode, the driving assistance state is established, and a task of front monitoring and a task of gripping the steering wheel  82  are imposed on the driver. The fourth driving mode is a driving mode in which a certain degree of driving operation by the driver is necessary for at least one of the steering and the acceleration and deceleration of the host vehicle M. For example, in the fourth driving mode, driving assistance such as adaptive cruise control (ACC) and lane keeping assist system (LKAS) is performed. In the fifth driving mode, both the steering and the acceleration and deceleration are in a manual driving state where a driving operation by the driver is necessary. In both the fourth driving mode and the fifth driving mode, naturally, the task of monitoring the front of the host vehicle M is imposed on the driver. 
     Returning to  FIG. 2 , the second control unit  160  performs control such that the host vehicle M passes through the target trajectory generated by the action plan generation unit  140  at a scheduled time point. The second control unit  160  includes, for example, an acquisition unit  162 , a speed control unit  164 , and a steering control unit  166 . 
     The acquisition unit  162  acquires information on the target trajectory (trajectory point) generated by the action plan generation unit  140 , and stores the acquired information in a memory (not shown). The speed control unit  164  controls the traveling driving force output apparatus  200  (see  FIG. 1 ) or the brake apparatus  210  (see  FIG. 1 ) based on a speed element associated with the target trajectory stored in the memory. The steering control unit  166  controls the steering apparatus  220  (see  FIG. 1 ) in accordance with a degree of curvature of the target trajectory stored in the memory. The processings of the speed control unit  164  and the steering control unit  166  are implemented by, for example, a combination of feedforward control and feedback control. 
     In the vehicle control apparatus  100 , a combination of the action plan generation unit  140  and the second control unit  160  constitutes the traveling control unit  170 . The traveling control unit  170  executes control of automatic lane change of the host vehicle M based on a recognition result of a traveling situation, a traveling environment, or the like of the host vehicle M recognized by the recognition unit  130 . 
     The traveling control unit  170  selects one lane change mode from a plurality of lane change modes having different degrees of involvement by the driver of the host vehicle M, and performs traveling control in accordance with the selected lane change mode. The plurality of lane change modes having different degrees of involvement by the driver of the host vehicle M can be referred to as a plurality of lane change modes having different degrees of automation. The smaller the degree of involvement by the driver is, the higher the degree of automation is, and the larger the degree of involvement by the driver is, the lower the degree of automation is. 
     For example, the plurality of lane change modes may include the following three automatic lane change modes. The first automatic lane change is an intended automatic lane change in which the driver of the host vehicle M himself/herself intends to change a lane and the driver of the host vehicle M instructs a start of the lane change. In the intended automatic lane change, the driver of the host vehicle M determines whether the lane change should be performed in consideration of a traveling situation of another vehicle, a route to a destination, and the like. When the lane change should be performed, the driver of the host vehicle M gives an instruction to start the lane change to the host vehicle M by operating the lane change button  86 . Based on the instruction, the traveling control unit  170  starts the automatic lane change at an executable timing in consideration of a surrounding traveling situation. 
     The second automatic lane change is a proposed automatic lane change in which the traveling control unit  170  proposes a lane change and the driver of the host vehicle M approves the lane change. In the proposed automatic lane change, the traveling control unit  170  determines whether the lane change should be performed based on a traveling situation of another vehicle, a route to a destination, and the like. When the lane change should be performed, the traveling control unit  170  proposes the lane change to the driver. When approving the proposal for the lane change, the driver of the host vehicle M gives an instruction to start the lane change to the host vehicle M by operating the lane change button  86 . Based on the instruction, the traveling control unit  170  starts the automatic lane change at an executable timing in consideration of a surrounding traveling situation. Therefore, when the driver does not approve the proposal for the lane change, that is, when the driver does not operate the lane change button  86 , the automatic lane change is not executed. 
     The third automatic lane change is a determination automatic lane change in which the traveling control unit  170  determines a lane change and the traveling control unit  170  determines to start the lane change. In the determination automatic lane change, the traveling control unit  170  determines whether the lane change should be performed based on a traveling situation of another vehicle, a route to a destination, and the like. When the lane change should be performed, the traveling control unit  170  starts the automatic lane change at an executable timing in consideration of a surrounding traveling situation. In a case of the determination automatic lane change, the driver of the host vehicle M is not involved in the lane change. 
     The vehicle control apparatus  100  executes an automatic lane change in accordance with a driving mode. For example, the vehicle control apparatus  100  may execute the determination automatic lane change in the first driving mode. The vehicle control apparatus  100  may execute the proposed automatic lane change in the second driving mode, the third driving mode, and the fourth driving mode. The vehicle control apparatus  100  may execute the intended automatic lane change in the third driving mode and the fourth driving mode. The vehicle control apparatus  100  does not execute any automatic lane change in the fifth driving mode. 
     Returning to  FIG. 1 , the traveling driving force output apparatus  200  outputs a traveling driving force (torque) for the vehicle to travel to driving wheels. The traveling driving force output apparatus  200  includes, for example, a combination of an internal combustion engine, an electric motor, a transmission, and the like, and an electronic control unit (ECU) that controls these components. The ECU controls the above-described configuration in accordance with information input from the second control unit  160  or information input from the driving operator  80 . 
     The brake apparatus  210  includes, for example, a brake caliper, a cylinder that transmits a hydraulic pressure to the brake caliper, an electric motor that causes the cylinder to generate a hydraulic pressure, and a brake ECU. The brake ECU controls the electric motor in accordance with the information input from the second control unit  160  or the information input from the driving operator  80  such that a brake torque in accordance with a braking operation is output to each wheel. 
     The steering apparatus  220  includes, for example, a steering ECU and an electric motor. The electric motor, for example, changes a direction of steered wheels by applying a force to a rack and pinion mechanism. The steering ECU drives the electric motor and changes the direction of the steered wheels in accordance with the information input from the second control unit  160  or the information input from the driving operator  80 . 
     Next, the automatic lane change executed by the traveling control unit  170  will be described with reference to  FIGS. 4 to 12 . As shown in  FIG. 4 , the host vehicle M travels in a center lane L 2  of a three-lane road including a left lane L 1 , the center lane L 2 , and a right lane L 3 . Other vehicles C other than the host vehicle M travel in the left lane L 1 , the center lane L 2 , and the right lane L 3 . 
     The traveling control unit  170  repeatedly executes, for example, a processing shown in  FIG. 5 . First, the traveling control unit  170  acquires various pieces of traveling information such as a traveling situation or a traveling environment of the host vehicle M recognized by the recognition unit  130  (step S 41 ). The various pieces of traveling information may include a state (a speed or the like) of the host vehicle M, a surrounding environment (a state of partition lines or the like), and states (speeds, positions, or the like of surrounding vehicles) of the surrounding vehicles. 
     Next, the traveling control unit  170  determines whether there is a preceding vehicle in the center lane L 2  in which the host vehicle M travels, based on current traveling information acquired from the recognition unit  130  (step S 42 ). The preceding vehicle referred to here is another vehicle that travels in front of the host vehicle M in the same lane as that of the host vehicle M at a speed lower than a traveling speed of the host vehicle M, and means another vehicle that the host vehicle M overtakes soon. 
     In step S 42 , when there is the preceding vehicle in the center lane L 2  (step S 42 : Yes), the traveling control unit  170  proceeds to a processing ( FIG. 8 ) of the proposed automatic lane change (overtaking) in step S 50 . 
     In step S 42 , when there is no preceding vehicle in the center lane L 2  (step S 42 : No), the traveling control unit  170  determines whether there is a following vehicle in the center lane L 2  in which the host vehicle M travels, based on the current traveling information acquired from the recognition unit  130  (step S 43 ). The following vehicle referred to here is another vehicle that travels behind the host vehicle M in the same lane as that of the host vehicle M at a speed higher than the traveling speed of the host vehicle M, and means another vehicle that overtakes the host vehicle M soon. 
     In step S 43 , when there is the following vehicle in the center lane L 2  (step S 43 : Yes), the traveling control unit  170  proceeds to a processing ( FIG. 10 ) of the proposed automatic lane change (yield) in step S 60 . 
     In step S 43 , when there is no following vehicle in the center lane L 2  (step S 43 : No), the traveling control unit  170  determines whether the lane change button  86  of the steering wheel  82  is pressed (step S 44 ). 
     In step S 43 , even when there is the following vehicle in the center lane L 2 , for example, when a distance between the host vehicle M and the following vehicle is equal to or larger than a threshold, the traveling control unit  170  may shift to step S 43 . 
     For example, as shown in  FIG. 6 , the lane change button  86  is provided at a position and in a shape where a blind operation can be performed with one of gripping hands (for example, one finger of a right hand) when the driver grips the steering wheel  82 . 
     In step S 44 , when the lane change button  86  is pressed (step S 43 : Yes), the traveling control unit  170  proceeds to a processing of the intended automatic lane change in step S 70  ( FIG. 12 ). 
     In step S 44 , when the lane change button  86  is not pressed (step S 44 : No), the traveling control unit  170  ends a series of processings. 
     &lt;Processing of Proposed Automatic Lane Change (Overtaking)&gt; 
     As shown in  FIG. 7 , in front of the host vehicle M that travels in the center lane L 2 , there is another vehicle C 1  (preceding vehicle) that travels in the same center lane L 2 . 
     As shown in  FIG. 8 , first, the traveling control unit  170  determines whether there is a lane adjacent to a right side (an example of a side in a specific direction) with respect to a lane in which the host vehicle M travels based on the current traveling information acquired from the recognition unit  130  (step S 51 ). Specifically, the traveling control unit  170  determines whether there is an overtaking lane for overtaking the other vehicle C 1  on a right side of the center lane L 2  in which the host vehicle M travels. 
     In step S 51 , when there is no lane on the right side of the lane in which the host vehicle M travels (step S 51 : No), the traveling control unit  170  continues traveling in the lane in which the host vehicle M currently travels, and ends the processing of the proposed automatic lane change (overtaking). 
     In step S 51 , when there is the lane on the right side of the lane in which the host vehicle M travels (step S 51 : Yes), the traveling control unit  170  proposes an overtaking lane change of changing the lane to the lane on the right side to the driver of the host vehicle M (step S 52 ). Specifically, the traveling control unit  170  proposes an overtaking lane change to the right lane L 3  present on the right side of the center lane L 2  in which the host vehicle M travels. 
     When proposing the overtaking lane change, the traveling control unit  170  displays a proposed content as a proposed image on, for example, the display apparatus of the HMI  30  in order to notify the driver of the proposed content. Specifically, as shown in a display apparatus  31  of the HMI  30  shown in  FIG. 7 , the right lane L 3  present on the right side of the center lane L 2  in which the host vehicle M travels is displayed in a colored (emphasized) manner as an overtaking lane  32  in which the host vehicle M moves to overtake the other vehicle C 1 . For example, “Please change the lane to the right lane in order to overtake the other vehicle C 1 ” may be proposed by voice from the speaker of the HMI  30 . Further, the proposed image may be displayed on the display apparatus of the navigation HMI  62 . 
     Next, the traveling control unit  170  determines whether the lane change button  86  is pressed within a certain period of time (for example, 20 to 30 seconds) after the overtaking lane change is proposed (step S 53 ). That is, the traveling control unit  170  determines whether the driver of the host vehicle M has approved the overtaking lane change within the certain period. of time in response to the proposal of the overtaking lane change from the traveling control unit  170 . 
     In step S 53 , when the lane change button  86  is pressed within the certain period of time (step S 53 : Yes), that is, when the driver approves the proposed overtaking lane change, the traveling control unit  170  executes the overtaking lane change to the lane on the right side of the host vehicle M (step S 54 ). Specifically, the traveling control unit  170  executes the overtaking lane change of the host vehicle M to the right lane L 3 . 
     In step S 53 , when the lane change button  86  is not pressed within the certain period of time (step S 53 : No), the traveling control unit  170  decreases the traveling speed of the host vehicle M while maintaining the current lane in which the host vehicle M travels (step S 55 ), and ends the processing of the proposed automatic lane change (overtaking). As described above, the other vehicle C 1  that is the preceding vehicle is the other vehicle that travels at a speed slower than that of the host vehicle M. Therefore, when the host vehicle M travels in this state, the host vehicle M may overtake the other vehicle C 1  soon. Therefore, when the driver of the host vehicle M does not approve the lane change for overtaking, the traveling control unit  170  decreases the traveling speed of the host vehicle M to follow the other vehicle C 1  while maintaining the current traveling lane. 
     After step S 54 , the traveling control unit  170  determines whether the host vehicle M that performs the overtaking lane change to the lane on the right side has overtaken the other vehicle C 1  based on the current traveling information acquired from the recognition unit  130  (step S 56 ). 
     In step S 56 , when the host vehicle M cannot overtake the other vehicle C 1  (step S 56 : No), the traveling control unit  170  repeats the processing of step S 56  until the host vehicle M can overtake the other vehicle C 1 . 
     In step S 56 , when the host vehicle M has overtaken the other vehicle C 1  (step S 56 : Yes), the traveling control unit  170  proposes, to the driver of the host vehicle M, a return lane change of changing the lane to a lane on a left side, that is, changing the lane to the original lane in which the host vehicle M travels before the overtaking is performed (step S 57 ). Specifically, the traveling control unit  170  proposes the return lane change of returning from the right lane L 3  in which the host vehicle M currently travels to the center lane L 2  on the left side of the right lane L 3 . 
     When proposing the return lane change, the traveling control unit  170  displays a proposed content as a proposed image on, for example, the display apparatus of the HMI  30  in order to notify the driver of the proposed content. Specifically, as shown in the display apparatus  31  shown in  FIG. 7 , the center lane L 2  present on the left side of the right lane L 3  in which the host vehicle M travels is displayed in a colored (emphasized) manner as a return lane  33  in which the host vehicle M returns. For example, “Please change the lane to the center lane since the other vehicle C 1  can be overtaken” may be proposed by voice from the speaker of the HMI  30 . 
     Next, the traveling control unit  170  determines whether the lane change button  86  is pressed within a certain period of time (for example, 20 to 30 seconds) after the return lane change is proposed (step S 58 ). That is, the traveling control unit  170  determines Whether the driver of the host vehicle M has approved the return lane change within the certain period of time in response to the proposal of the return lane change from the traveling control unit  170 . The operation of pressing the lane change button  86  for the proposal of the return lane change in step S 58  is an operation of the same content as that of the operation of pressing the lane change button  86  for the proposal of the overtaking lane change in step S 53 . 
     In step S 58 , when the lane change button  86  is not pressed within the certain period of time (step S 58 : No), the traveling control unit  170  returns to step S 57  and proposes the return lane change of changing the lane to the original lane to the driver of the host vehicle M again. When proposing the return lane change again, the number of times of the proposal may be increased as compared with the case of the originally proposed return lane change. For example, in the display apparatus  31  shown in  FIG. 7 , the display of the right lane L 3  in which the host vehicle M currently travels may be omitted, and the return lane  33  in which the host vehicle M returns may be further highlighted. 
     In step S 58 , when the lane change button  86  is pressed within the certain period of time (step S 58 : Yes), that is, when the driver approves the proposed return lane change, the traveling control unit  170  executes the return lane change to the lane on the left side of the host vehicle M (step S 59 ). Specifically, the traveling control unit  170  executes the return lane change of the host vehicle M to the center lane L 2 . When the host vehicle M overtakes the preceding vehicle (the other vehicle C 1 ) and further returns to the center lane L 2  that is the original traveling lane, the traveling control unit  170  ends the processing of the proposed automatic lane change (overtaking). 
     In this way, according to the vehicle control apparatus  100 , the lane changes of the “overtaking lane change” and the “return lane change” when the host vehicle M travels by overtaking the preceding vehicle (the other vehicle C 1 ) can be easily executed by a simple operation of the same content, for example, simply pressing the lane change button  86  once. 
     In the above embodiment, a case where the host vehicle M travels in the center lane L 2  has been described, but fir example, the same processing can be executed also in a case where the host vehicle M travels in the left lane L 1 . However, when the host vehicle M that travels in the left lane L 1  performs the overtaking lane change to the center lane L 2  to overtake the preceding vehicle, the traveling control unit  170  may perform control that does not propose the return lane change of returning to the left lane L 1  after the overtaking. In this case, the traveling control unit  170  may cause the host vehicle M to continue traveling in the center lane L 2  as it is. 
     For example, in a case where the host vehicle M travels in the right lane L 3 , when there is a preceding vehicle haying a low speed, the traveling control unit  170  may propose the overtaking lane change in which the host vehicle M is moved to the center lane L 2  that is the lane on the left side to the driver of the host vehicle M in order to avoid approach to the preceding vehicle. In this case, when the lane change button  86  is pressed by the driver of the host vehicle M, the traveling control unit  170  can cause the host vehicle M to overtake while avoiding the preceding vehicle having the low speed by causing the host vehicle M to travel in the center lane L 2 . Also in this case, the traveling control unit  170  may perform control that does not propose the return lane change of returning to the right lane L 3  after the overtaking. 
     &lt;Processing of Proposed Automatic Lane Change (Yield)&gt; 
     As shown in  FIG. 9 , behind the host vehicle M that travels in the center lane L 2 , there is another vehicle C 2  (following vehicle) that travels in the same center lane L 2 . 
     As shown in  FIG. 10 , first, the traveling control unit  170  determines whether there is a lane adjacent to a left side with respect to the lane in which the host vehicle M travels based on current traveling information acquired from the recognition unit  130  (step S 61 ). Specifically, the traveling control unit  170  determines whether there is a yield lane to which the host vehicle M moves in order to yield the traveling in the center lane L 2  to the other vehicle C 2  on the left side of the center lane L 2  in which the host vehicle M travels. 
     In step S 61 , when there is no lane on the left side of the lane in which the host vehicle M travels (step S 61 : No), the traveling control unit  170  continues traveling in the lane in which the host vehicle M currently travels, and ends the processing of the proposed automatic lane change (yield). 
     In step S 61 , when there is the lane on the left side of the lane in which the host vehicle M travels (step S 61 : Yes), the traveling control unit  170  proposes the yield lane change of changing the lane to the lane on the left side to the driver of the host vehicle M (step S 62 ). Specifically, the traveling control unit  170  proposes the yield lane change to the left lane L 1  present on the left side of the center lane L 2  in which the host vehicle M travels. 
     When proposing the yield lane change, the traveling control unit  170  displays a proposed content as a proposed image on, for example, the display apparatus of the HMI  30  in order to notify the driver of the proposed content. Specifically, as shown in the display apparatus  31  shown in  FIG. 9 , the left lane L 1  present on the left side of the center lane L 2  in which the host vehicle M travels is displayed in a colored (emphasized) manner as a yield lane  34  to which the host vehicle M moves to yield the lane to the other vehicle C 2 . For example, “Please change the lane to the left lane in order to yield the lane to the other vehicle C 2 ” may be proposed by voice from the speaker of the HMI  30 . Further, the proposed image may be displayed on the display apparatus of the navigation HMI  62 . 
     Next, the traveling control unit  170  determines whether the lane change button  86  is pressed within a certain period of time (for example, 20 to 30 seconds) after the yield lane change is proposed (step S 63 ). That is, the traveling control unit  170  determines whether the driver of the host vehicle M has approved the yield lane change within the certain period of time in response to the proposal of the yield lane change from the traveling control unit  170 . 
     In step S 63 , when the lane change button  86  is pressed within the certain period of time (step S 63 : Yes), that is, when the driver approves the proposed yield lane change, the traveling control unit  170  executes the yield lane change of moving to the lane on the left side of the host vehicle M (step S 64 ). Specifically, the traveling control unit  170  executes the yield lane change of the host vehicle M that moves to the left lane L 1 . 
     In step S 63 , when the lane change button  86  is not pressed within the certain period of time (step S 63 : No), the traveling control unit  170  increases the traveling speed of the host vehicle M while maintaining the current lane in which the host vehicle M travels (step S 65 ), and ends the processing of the proposed automatic lane change (yield). As described above, the other vehicle C 2  that is the following vehicle is the other vehicle that travels at a speed higher than that of the host vehicle M. Therefore, when the host vehicle M travels in this state, the host vehicle M may be overtaken by the other vehicle C 2  soon. Therefore, in a case where the driver of the host vehicle M does not approve the lane change for yielding the lane, when there is no other vehicle in front of the lane in which the host vehicle M travels, the traveling control unit  170  increases the traveling speed of the host vehicle M while maintaining the current traveling lane so as not to interfere with traveling of the other vehicle C 2 . 
     After step S 64 , the traveling control unit  170  determines whether the host vehicle M, which has performed the yield lane change of moving to the lane on the left side, has been overtaken by the other vehicle C 2  based on current traveling information acquired from the recognition unit  130  (step S 66 ). 
     In step S 66 , when the host vehicle M is not overtaken by the other vehicle C 2  (step S 66 : No), the traveling control unit  170  repeats the processing of step S 66  until the host vehicle M is overtaken. 
     In step S 66 , when the host vehicle M is overtaken by the other vehicle C 2  (step S 66 : Yes), the traveling control unit  170  proposes, to the driver of the host vehicle M, a return lane change of changing the lane to the lane on the right side, that is, changing the lane to the original lane in which the host vehicle M travels before yielding the lane to the other vehicle C 2  (step S 67 ). Specifically, the traveling control unit  170  proposes the return lane change of returning from the left lane L 1  in which the host vehicle M currently travels to the center lane L 2  on the right side of the left lane L 1 . 
     When proposing the return lane change, the traveling control unit  170  displays a proposed content as a proposed image on, for example, the display apparatus of the HMI  30  in order to notify the driver of the proposed content. Specifically, as shown in the display apparatus  31  shown in  FIG. 9 , the center lane L 2  present on the right side of the left lane L 1  in which the host vehicle M travels is displayed in a colored (emphasized) manner as a return lane  35  to which the host vehicle M returns. For example, “Please change the lane to the center lane since the host vehicle M is overtaken by the other vehicle C 2 ” may be proposed by voice from the speaker of the HMI  30 . 
     Next, the traveling control unit  170  determines whether the lane change button  86  is pressed within a certain period of time (for example, 20 to 30 seconds) after the return lane change is proposed (step S 68 ). That is, the traveling control unit  170  determines whether the driver of the host vehicle M has approved the return lane change within the certain period of time in response to the proposal of the return lane change from the traveling control unit  170 . The operation of pressing the lane change button  86  for the proposal of the return lane change in step S 68  is an operation of the same content as that of the operation of pressing the lane change button  86  for the proposal of the yield lane change in step S 63 . 
     In step S 68 , when the lane change button  86  is not pressed within the certain period of time (step S 68 : No), the traveling control unit  170  returns to step S 67  and proposes the return lane change of changing the lane to the original lane to the driver of the host vehicle M again. When proposing the return lane change again, the number of times of the proposal may be increased as compared with the case of the originally proposed return lane change. For example, in the display apparatus  31  shown in  FIG. 9 , the display of the left lane L 1  in which the host vehicle M currently travels may be omitted, and the return lane  35  to which the host vehicle M returns may be further highlighted. 
     In step S 68 , when the lane change button  86  is pressed within the certain period of time (step S 68 : Yes), that is, when the driver approves the proposed return lane change, the traveling control unit  170  executes the return lane change of returning to the lane on the right side of the host vehicle M (step S 69 ). Specifically, the traveling control unit  170  executes the return lane change of the host vehicle M that returns to the center lane L 2 . When the host vehicle M yields the lane to the following vehicle (the other vehicle C 2 ), is overtaken by the following vehicle, and returns to the center lane L 2  that is the original traveling lane, the traveling control unit  170  ends the processing of the proposed automatic lane change (yield). 
     In this way, according to the vehicle control apparatus  100 , the lane changes of the “yield lane change” and the “return lane change” when the host vehicle M yields the traveling lane to the following vehicle (the other vehicle C 2 ) can be easily executed by a simple operation of the same content, for example, simply pressing the lane change button  86  once. 
     In the above embodiment, a case where the host vehicle M travels in the center lane L 2  has been described, but for example, the same processing can be executed also in a case where the host vehicle M travels in the right lane L 3 . However, when the host vehicle M that travels in the right lane L 3  performs the yield lane change to the center lane L 2  and yields the lane to the following vehicle, the traveling control unit  170  executes control that does not propose a return lane change of returning to the right lane L 3  after the overtaking. In this case, the traveling control unit  170  performs control such that the host vehicle M continues traveling in the center lane L 2  as it is. 
     For example, in a case where the host vehicle M travels in the left lane L 1 , when there is a following vehicle, the traveling control unit  170  may propose, to the driver of the host vehicle M, a yield lane change in which the host vehicle M is moved to the center lane L 2  that is the lane on the right side in order to yield the lane to the following vehicle. In this case, when the lane change button  86  is pressed by the driver of the host vehicle M, the traveling control unit  170  can cause the host vehicle M to travel in the center lane L 2 , so that it is possible to avoid approach to the following vehicle having a high speed and allow the following vehicle to overtake the host vehicle M. Also in this case, the traveling control unit  170  may perform control that does not propose a return lane change of returning to the left lane L 1  after the overtaking. 
     &lt;Processing of Intended Automatic Lane Change&gt; 
     As shown in  FIG. 11 , the host vehicle M travels in the center lane L 2 . 
     When the lane change button  86  is pressed in step S 44  of  FIG. 5 , as shown in  FIG. 12 , first, the traveling control unit  170  determines whether there is a lane adjacent to a right side with respect to the lane in which the host vehicle M travels based on current traveling information acquired from the recognition unit  130  (step S 71 ). Specifically, the traveling control unit  170  determines whether there is a movable lane in which the host vehicle M can move to the right side of the center lane L 2  in which the host vehicle M travels. 
     In step S 71 , when there is the lane on the right side of the lane in which the host vehicle M travels (step S 71 : Yes), the traveling control unit  170  displays an advance notice as a moving lane image on, for example, the display apparatus of the HMI  30  in order to notify the driver that there is the movable lane on the right side (step S 72 ). Specifically, as shown in the display apparatus  31  shown in  FIG. 11 , the right lane L 3  present on the right side of the center lane L 2  in which the host vehicle M travels is displayed in a colored (emphasized) mariner as a movable lane  36 . For example, “change the lane to the right lane based on the instruction” may be notified by voice from the speaker of the HMI  30 . Further, the moving lane image may be displayed on the display apparatus of the navigation HMI  62 . 
     Next, the traveling control unit  170  executes the intended automatic lane change to the lane on the right side of the host vehicle M in accordance with an intention of the driver (step S 73 ). Specifically, the traveling control unit  170  executes the intended automatic lane change of the host vehicle M that moves from the center lane L 2  to the right lane L 3 . 
     In step S 71 , when there is no lane on the right side of the lane in which the host vehicle M travels (step S 71 : No), the traveling control unit  170  determines whether there is a lane adjacent to the left side with respect to the lane in which the host vehicle M travels based on the current traveling information acquired from the recognition unit  130  (step S 74 ). Specifically, the traveling control unit  170  determines whether there is a movable lane in which the host vehicle M can move to the left side of the center lane L 2  in which the host vehicle M travels. 
     In step S 74 , when there is the lane on the left side of the lane in which the host vehicle M travels (step S 74 : Yes), the traveling control unit  170  displays an advance notice as a moving lane image on, for example, the display apparatus of the HMI  30  in order to notify the driver that there is the movable lane on the left side (step S 75 ). For example, when the host vehicle M travels in the right lane L 3 , the traveling control unit  170  displays the center lane L 2  present on the left side of the right lane L 3  in which the host vehicle M travels as a movable lane  37  in a colored (emphasized) manner as shown in the display apparatus  31  shown in  FIG. 11 . For example, “change the lane to the left lane based on the instruction” may be notified by voice from the speaker of the HMI  30 . 
     Next, the traveling control unit  170  executes an intended automatic lane change to the lane on the left side of the host vehicle M in accordance with an intention of the driver (step S 76 ). For example, when the host vehicle M travels in the right lane L 3 , the traveling control unit  170  executes the intended automatic lane change of the host vehicle M that moves from the right lane L 3  to the center lane L 2 . 
     In step S 74 , when there is no lane on the left side of the lane in which the host vehicle M travels (step S 74 : No), the traveling control unit  170  continues traveling in the lane in which the host vehicle M currently travels, and ends the processing of the intended automatic lane change. 
     In this way, according to the vehicle control apparatus  100 , the lane changes of the right lane change to the lane present on the right side and the left lane change to the lane present on the left side with respect to the lane in which the host vehicle M travels can be easily executed by a simple operation of the same content, for example, simply pressing the lane change button  86  once. 
     In the above embodiment, a case where the host vehicle M travels in the center lane L 2  or the right lane L 3  has been described, but for example, the same processing can be executed also in a case where the host vehicle M travels in the left lane L 1 . However, when the host vehicle M travels in the left lane L 1 , the traveling control unit  170  causes the host vehicle M to perform the intended automatic lane change from the left lane L 1  to the center lane L 2  by firstly pressing the lane change button  86 , and causes the host vehicle M to perform the intended automatic lane change from the center lane L 2  to the right lane L 3  by secondly pressing the lane change button  86 . 
     Examples of a situation in which the intended automatic lane change is executed include a case where there is an obstacle in front of the lane in which the host vehicle M travels, a case where a large vehicle travels in front of the lane, and a case where the number of traveling lanes changes in front of the lane. 
     Even when there is a lane on the right side of the host vehicle M, the traveling control unit  170  can also perform control such that the lane of the host vehicle M is automatically changed to the lane on the left side. In this case, for example, a reverse lane change button  87  may be provided on the steering wheel  82  separately from the lane change button  86  (see  FIG. 6 ). When the reverse lane change button  87  is pressed by the driver, the traveling control unit  170  causes the host vehicle M to automatically change the lane to the lane on the left side even when there is a lane on the right side of the host vehicle M. Specifically, when the reverse lane change button  87  is pressed by the driver of the host vehicle M, the traveling control unit  170  causes the host vehicle M to automatically change the lane to the left lane L 1  on the left side even when there is the right lane L 3  on the right side of the host vehicle M. Instead of operating the reverse lane change button  87 , when a turn lever is operated by using the existing turn lever, the lane of the host vehicle M may be automatically changed to the left lane L 1  on the left side. Alternatively, instead of operating the reverse lane change button  87 , when the lane change button  86  is pressed twice in succession by using the lane change button  86 , the lane of the host vehicle M may be automatically changed to the left lane L 1  on the left side. 
     Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and modifications, improvements, and the like can be made as appropriate. 
     For example, in the above embodiment, the processings of the proposed automatic lane change (overtaking, yield) and the intended automatic lane change when the host vehicle M travels in the three-lane road have been described, but the present invention is not limited thereto. For example, the same processing can be executed also in a case where the host vehicle M travels on a road of two lanes or in a case where the host vehicle M travels on a road of four or more lanes. 
     In the above embodiment, a case has been described in which each of the “overtaking lane change” and the “return lane change”, each of the “yield lane change” and the “return lane change”, and each of the “right lane change” and the “left lane change” are executed by the operation of the same content of pressing the lane change button  86 , but the present invention is not limited thereto. For example, when the lane change button  86  is pressed once, both lane changes of the “overtaking lane change” and the “return lane change”, both lane changes of the “yield lane change” and the “return lane change”, and both lane changes of the “right lane change” and the “left lane change” may be controlled to be executed as a series of lane changes. 
     In the above embodiment, control is performed such that the “overtaking lane change” and the “return lane change”, the “yield lane change” and the “return lane change”, and the “right lane change” and the “left lane change” are executed by the driver operating the lane change button  86 , but the present invention is not limited thereto. For example, control may be performed such that the lane changes are executed by a voice input of the driver. In this case, control is performed such that each of the “overtaking lane change” and the “return lane change”, each of the “yield lane change” and the “return lane change”, and each of the “right lane change” and the “left lane change” are executed only by the driver pronouncing the same instruction voice of a “lane change”. 
     In the above embodiment, the lane on the right side is described as the lane on an overtaking side (a side of a specific direction) and the lane on the left side is described as the lane on a yield side (a side opposite to the specific direction), but depending on a region where the host vehicle M travels, the lane on the left side is the lane on the overtaking side (the side of the specific direction) and the lane on the right side is the lane on the yield side (the side opposite to the specific direction). 
     The present specification describes at least the following matters. Although the corresponding components or the like in the above embodiment are shown in parentheses, the present invention is not limited thereto. 
     (1) A vehicle control apparatus including: 
     a recognition unit (the recognition unit  130 ) configured to recognize an environment in a vicinity of a vehicle (the host vehicle M); and 
     a traveling control unit (the traveling control unit  170 ) configured to execute a lane change of the vehicle based on a recognition result by the recognition unit, 
     in which the traveling control unit selectively executes a lane change of the vehicle based on proposal information of a lane change output to a driver of the vehicle by the traveling control unit and a lane change of the vehicle not based on the proposal information in response to a first operation (pressing the lane change button  86 ) of the same content by the driver. 
     According to (1), since the driver can perform the lane change based on the proposal from a vehicle control apparatus side and the lane change intended by the driver himself/herself without based on the proposal from the vehicle control apparatus side by the first operation of the same content, an operation in accordance with a type of the lane change becomes unnecessary, and the operation of the lane change can be facilitated. 
     (2) The vehicle control apparatus according to (1), 
     in which the traveling control unit selectively executes, in response to the first operation, a first lane change (the overtaking lane change, the yield lane change) in which the vehicle is moved from a first lane (the center lane L 2 ) to a second lane (the right lane L 3 , the left lane L 1 ) based on the proposal information, a second lane change (the return lane change) in which the vehicle moved to the second lane by the first lane change is moved to the first lane, a third lane change (the intended automatic lane change) in which the vehicle is moved from the first lane (the center lane L 2 ) to the second lane (the right lane L 3 , the left lane L 1 ) without based on the proposal information, and a fourth lane change (the intended automatic lane change) in which the vehicle moved to the second lane by the third lane change is moved to the first lane. 
     In the vehicle control apparatus  100 , the “first lane” means a lane in which the host vehicle M currently travels. The “second lane” means a lane on an overtaking side (for example, the right side) of the lane in which the host vehicle M currently travels. The “third lane” means a lane on a side (for example, the left side) opposite to the overtaking side of the lane in which the host vehicle M currently travels. 
     According to (2), since the driver can perform the first lane change for overtaking or the like based on the proposal from the vehicle control apparatus side, the second lane change of returning to the original lane after the first lane change, the third lane change for overtaking or the like intended by the driver himself/herself without based on the proposal from the vehicle control apparatus side, and the fourth lane change of returning to the original lane after the third lane change by the first operation of the same content, an operation in accordance with a type of the lane change or a direction of the lane change becomes unnecessary, and the operation of the lane change can be further facilitated. 
     (3) The vehicle control apparatus according to (2), 
     in which in the lane change of the vehicle not based on the proposal information, the traveling control unit performs the third lane change in which the vehicle is moved to the second lane when the first operation is performed in a case where there is the second lane (the right lane L 3 ) adjacent to a side in a specific direction (the right side) with respect to the first lane (the center lane L 2 ), and performs the third lane change in which the vehicle is moved to a third lane (the left lane L 1 ) adjacent to a side (the left side) opposite to the specific direction with respect to the first lane when the first operation is performed in a case where there is no second lane. 
     According to (3), when performing the lane change intended by the driver himself/herself without based on the proposal from the vehicle control apparatus side, the driver can automatically select a direction of the lane change in accordance with presence or absence of the left and right adjacent lanes of the lane in which the vehicle travels and perform the lane change by performing the first operation regardless of a direction of the lane change. For example, the driver can perform the lane change toward the overtaking lane and the lane change from the overtaking lane to the traveling lane by the first operation of the same content. Therefore, the operation of the lane change can be further facilitated. For example, it is assumed that a side in a specific direction is the right side and there are the left lane, the center lane, and the right lane. In this case, when the first operation is performed while the vehicle is in the left lane, the lane is changed from the left lane to the center lane. When the first operation is performed again in the state, the lane is changed from the center lane to the right lane. 
     (4) The vehicle control apparatus according to (3), 
     in which the traveling control unit moves the vehicle to the third lane when a second operation (pressing the reverse lane change button  87 ) different from the first operation is performed in a case where there is the second lane. 
     According to (4), the driver can perform a lane change in a direction opposite to a direction of the lane change automatically selected during the first operation by performing the second operation. For example, the driver may perform the second operation when the driver wants to perform a lane change to a lane on a side opposite to the overtaking lane while traveling in the center lane among the three lanes. Accordingly, it is also possible to automatically select a direction of the lane change during the first operation, and to perform the lane change in a direction opposite to the direction of the lane change automatically selected during the first operation. 
     (5) The vehicle control apparatus according to any one of (2) to (4), 
     in which in a case where there is a preceding vehicle (the other vehicle C 1 ) of the vehicle in the first lane, the traveling control unit outputs the proposal information that proposes the first lane change (the overtaking lane change), and executes the first lane change when the first operation is performed after the proposal information that proposes the first lane change is output, and in a case where the vehicle overtakes the preceding vehicle on the second lane after the first lane change, the traveling control unit outputs proposal information that proposes the second lane change (the return lane change), and executes the second lane change when the first operation is performed after the proposal information that proposes the second lane change is output. 
     According to (5), when performing the lane change based on the proposal from the vehicle control apparatus side, the driver can perform the lane change by performing the first operation when approving the proposed lane change regardless of a direction of the lane change. For example, since the driver can perform the lane change toward the overtaking lane and the lane change from the overtaking lane to the traveling lane by the first operation of the same content, the operation of the lane change can be further facilitated. 
     (6) The vehicle control apparatus according to (5), 
     in which when there is the preceding vehicle in the first lane and there is the second. lane adjacent to a side in a specific direction with respect to the first lane, the traveling control unit outputs the proposal information that proposes the first lane change (the overtaking lane change) of moving the vehicle to the second lane, and 
     in which when there is the preceding vehicle in the first lane and there is no second lane, the traveling control unit outputs the proposal information that proposes the first lane change (the overtaking lane change) of moving the vehicle to a third lane adjacent to a side opposite to the specific direction with respect to the first lane. 
     According to (6), when performing the lane change based on the proposal from the vehicle control apparatus side, the driver can automatically select a direction of the lane change in accordance with presence or absence of the left and right adjacent lanes of the lane in which the vehicle travels and perform the lane change by performing the first operation regardless of a direction of the lane change. For example, the driver can perform the lane change toward the overtaking lane and the lane change from the overtaking lane to the traveling lane by the first operation of the same content. Therefore, the operation of the lane change can be further facilitated. 
     (7) The vehicle control apparatus according to (6), 
     in which when there is a following vehicle (the other vehicle C 2 ) of the vehicle in the first lane, the traveling control unit outputs the proposal information that proposes the first lane change (the yield lane change) of moving the vehicle to the third lane. 
     According to (7), when there is the following vehicle, it is possible to propose to the driver the lane change to the lane on a side opposite to that in a case where there is the preceding vehicle. Also in this case, the driver can perform the lane change based on the proposal from the vehicle control apparatus side by performing the first operation. 
     (8) The vehicle control apparatus according to (7), 
     in which when a distance between the vehicle and the following vehicle satisfies a predetermined condition, the traveling control unit outputs the proposal information that proposes the first lane change of moving the vehicle to the third lane. 
     According to (8), it is possible to propose to the driver the lane change in accordance with presence of the following vehicle and the distance between the vehicle and the following vehicle. For example, even when there is the following vehicle, when the distance between the vehicle and the following vehicle is sufficient (equal to or larger than a threshold), it is possible not to propose the lane change to the driver. 
     (9) The vehicle control apparatus according to any one of (5) to (8), 
     in which the traveling control unit maintains the vehicle in the first lane when the first operation is not performed within a predetermined time after the proposal information that proposes the first lane change (the overtaking lane change, the yield lane change) is output. 
     According to (9), when the driver does not approve the first lane change for overtaking or the like, it is possible to maintain the lane in accordance with an intention of the driver and continue following the preceding vehicle. 
     (10) The vehicle control apparatus according to any one of (5) to (9), 
     in which when the first operation is not performed within a predetermined time after the proposal information that proposes the second lane change (the return lane change) is output, the traveling control unit outputs the proposal information that proposes the second lane change again. 
     According to (10), when the driver does not approve the second lane change of returning to the original lane after the first lane change is performed for overtaking or the like, the driver can be prompted to perform the second lane change of returning to the original lane again. 
     (11) The vehicle control apparatus according to any one of (1) to (10), further including: 
     a display unit (the display apparatus  31 ) configured to display a lane of a movement destination based on the lane change to the driver before the lane change. 
     According to (11), it is possible to easily notify the driver of a lane to which the vehicle moves by performing the first operation. Therefore, when the driver desires to change the lane to the displayed movement destination, the driver may perform the first operation, and the operation of the lane change can be further facilitated. 
     (12) The vehicle control apparatus according to any one of (1) to (11), 
     in which the first operation is pressing a pressing button (the lane change button  86 ) provided on a steering apparatus (the steering wheel  82 ) of the vehicle. 
     According to (12), since the driver can perform the lane change by pressing the pressing button provided on the steering apparatus gripped during driving, the operation of the lane change can be further facilitated.