Vehicle control program, vehicle control device, and vehicle control method

Abstract

To provide a vehicle control program, a vehicle control device, and a vehicle control method that can set a more appropriate target speed even on a curved road.SOLUTION: A vehicle control program according to an embodiment causes a computer to execute the steps of: recognizing a surrounding situation of a vehicle on the basis of a detection result of an external environment detection device; setting a first target speed of the vehicle on the basis of the surrounding situation; setting a second target speed of the vehicle on the basis of map information; and selecting one of the first target speed and the second target speed, and controlling the speed of the vehicle on the basis of the selected target speed. When a curved road exists in a traveling direction of the vehicle, the program sets a target speed by combining the first target speed and the second target speed at a ratio corresponding to a traveling condition of the vehicle, and controls the speed of the vehicle on the basis of the set target speed.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a vehicle control program, a vehicle control device, and a vehicle control method. [Background technology]

[0002] In recent years, efforts to provide access to sustainable transportation systems that take into consideration vulnerable traffic participants have been gaining momentum. To achieve this, efforts are being made to further improve traffic safety and convenience through research and development of preventive safety technologies. In this regard, a technology has been disclosed that controls the traveling speed of a vehicle at a set speed according to the magnitude of the curve of the road (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 230300 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in preventive safety technology, when the target speed is set using the curvature of a curved road obtained from the results of camera detection, the curvature detected by the camera can change significantly due to changes in the vehicle direction caused by the driver's steering operation, which has led to a problem in that the target speed may not be adjusted appropriately according to the shape of the curved road.

[0005] In order to solve the above-mentioned problems, one of the objects of the present application is to provide a vehicle control program, a vehicle control device, and a vehicle control method that can set a more appropriate target speed even on curved roads, thereby contributing to the development of sustainable transportation systems. [Means for solving the problem]

[0006] The vehicle control program, the vehicle control device, and the vehicle control method according to the present invention employ the following configuration. (1): A vehicle control program according to one embodiment of the present invention causes a computer to recognize the surrounding conditions of a vehicle based on the detection results of an external environment detection device, set a first target speed for the vehicle based on the surrounding conditions, set a second target speed for the vehicle based on map information, select one of the first target speed and the second target speed, and control the speed of the vehicle based on the selected target speed.When a curved road is present in the direction of travel of the vehicle, the vehicle control program sets the target speed by combining the first target speed and the second target speed in a ratio that corresponds to the driving conditions of the vehicle, and controls the speed of the vehicle based on the set target speed.

[0007] (2) In the above aspect (1), when the relative speed between the target speed and the speed of the vehicle is high, the ratio of the second target speed is increased.

[0008] (3): In the above aspect (1), when the relative speed between the target speed and the speed of the vehicle is large, the ratio of the smaller target speed between the first target speed and the second target speed is increased.

[0009] (4) In the above aspect (1), the first target speed and the second target speed are set in accordance with the radius of curvature or the curvature of the curved road.

[0010] (5) In the above aspect (4), the first target speed is adjusted based on the yaw rate or steering angle of the vehicle.

[0011] (6): Another aspect of the present invention provides a vehicle control device that includes a recognition unit that recognizes the surrounding conditions of the vehicle based on the detection results of an external detection device; a target speed setting unit that sets a first target speed of the vehicle based on the surrounding conditions recognized by the recognition unit and sets a second target speed of the vehicle based on map information; and a speed control unit that selects one of the first target speed and the second target speed and controls the speed of the vehicle based on the selected target speed, wherein when a curved road is present in the direction of travel of the vehicle, the target speed setting unit sets the target speed by combining the first target speed and the second target speed in a ratio that corresponds to the driving conditions of the vehicle, and the speed control unit controls the speed of the vehicle based on the set target speed.

[0012] (7): Another aspect of the present invention is a vehicle control method in which a computer recognizes the surrounding conditions of a vehicle based on the detection results of an external detection device, sets a first target speed for the vehicle based on the surrounding conditions, sets a second target speed for the vehicle based on map information, selects one of the first target speed and the second target speed, controls the speed of the vehicle based on the selected target speed, and, when a curved road is present in the direction of travel of the vehicle, sets a target speed by combining the first target speed and the second target speed in a ratio according to the driving conditions of the vehicle, and controls the speed of the vehicle based on the set target speed. [Effects of the Invention]

[0013] According to the above aspects (1) to (7), a more appropriate target speed can be set even on a curved road. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a configuration diagram of a vehicle system 1 to which a vehicle control device according to an embodiment is applied. [Figure 2] FIG. 1 is a diagram for explaining a situation in which a vehicle M is traveling near a curved road. [Figure 3] FIG. 10 is a diagram illustrating an example of a target speed relative to the radius of curvature of a driving lane. [Figure 4] 10 is a diagram for explaining the difference in speed control of a vehicle M based on a first target speed and a second target speed set for the same radius of curvature. FIG. [Figure 5] 10 is a diagram for explaining a change in the speed of the vehicle M based on an adjusted target speed. FIG. [Figure 6] 3 is a flowchart showing an example of processing executed by the driving assistance device 100 in the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a vehicle control program, a vehicle control device, and a vehicle control method according to the present invention will be described with reference to the accompanying drawings.

[0016] [Overall configuration] 1 is a configuration diagram of a vehicle system 1 to which a vehicle control device according to an embodiment is applied. The vehicle (hereinafter referred to as 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 of these. The electric motor operates using power generated by a generator connected to the internal combustion engine, or discharged power from a secondary battery or a fuel cell.

[0017] The vehicle M is equipped with, 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, vehicle sensors 40, a navigation device 50, an MPU (Map Positioning Unit) 60, a driving operator 80, a driving assistance device 100, a driving force output device 200, a braking device 210, and a steering device 220. These devices and equipment are connected to each other via multiplex communication lines such as a CAN (Controller Area Network) communication line, serial communication lines, a wireless communication network, etc. Note that the configuration shown in FIG. 1 is merely an example, and some of the configuration may be omitted, or other configurations may be added. The driving assistance device 100 is an example of a "vehicle control device."

[0018] The camera 10 is, for example, a digital camera that uses a solid-state imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The camera 10 is attached to any location on the vehicle M. For example, when capturing an image of the area ahead of the vehicle M, the camera 10 is attached to the top of the front windshield or the back of the rearview mirror. The camera 10, for example, periodically and repeatedly captures images of the area around the vehicle M. The camera 10 may be a stereo camera.

[0019] The radar device 12 emits radio waves such as millimeter waves around the vehicle M and detects radio waves reflected by an object (reflected waves) to detect at least the position (distance and direction) of the object. The radar device 12 is attached to any location on the vehicle M. The radar device 12 may detect the position and speed of an object using an FM-CW (Frequency Modulated Continuous Wave) method.

[0020] The LIDAR 14 irradiates the surroundings of the vehicle M with light (or electromagnetic waves with wavelengths similar to light) and measures the scattered light. The LIDAR 14 detects the distance to the target based on the time between light emission and light reception. The irradiated light is, for example, pulsed laser light. The LIDAR 14 may be attached to any location on the vehicle M.

[0021] The object recognition device 16 performs sensor fusion processing on the detection results from 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 results to the driving assistance device 100. The object recognition device 16 may output the detection results from the camera 10, the radar device 12, and the LIDAR 14 directly to the driving assistance device 100. The object recognition device 16 may be omitted from the vehicle M. Some or all of the camera 10, the radar device 12, the LIDAR 14, and the object recognition device 16 are an example of an "external environment detection device DD."

[0022] The communication device 20 communicates with other vehicles in the vicinity of the vehicle M, for example, using a cellular network, a Wi-Fi network, Bluetooth (registered trademark), DSRC (Dedicated Short Range Communication), etc., or communicates with various server devices via a wireless base station.

[0023] The HMI 30 presents various information to occupants (including the driver) of the vehicle M and accepts input operations by the occupants. The HMI 30 includes, for example, a display unit and a speaker. The display unit is, for example, an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) display device. The display unit displays various images (including videos). The display unit may be configured as a touch panel integrated with the input unit. The speaker outputs a predetermined sound (for example, an alarm). Furthermore, the HMI 30 may include, in addition to (or instead of) the display unit and speaker, a microphone, a buzzer, a vibration generator (vibrator), a touch panel, a switch, a key, or the like. The switch includes, for example, a changeover switch that switches whether or not a predetermined driving control is executed in the driving assistance device 100.

[0024] The vehicle sensor 40 includes a speed sensor that detects the speed of the vehicle M, an acceleration sensor that detects acceleration, a yaw rate sensor that detects the yaw rate (for example, the rotational angular velocity around a vertical axis passing through the center of gravity of the vehicle M), a steering angle sensor that detects the steering angle (the angle (actual steering angle) or torque amount of the steering wheel of the vehicle M), and a direction sensor that detects the direction of the vehicle M. The vehicle sensor 40 may also be provided with a position sensor that detects the position of the vehicle M. The position sensor is, for example, a sensor that acquires position information (longitude and latitude information) from a GPS (Global Positioning System) device. The position sensor may also be a sensor that acquires position information using a GNSS (Global Navigation Satellite System) receiver 51 of the navigation device 50.

[0025] The navigation device 50 includes, for example, a GNSS receiver 51, a navigation HMI 52, and a route determination unit 53. The navigation device 50 stores first map information 54 in a storage device such as a hard disk drive (HDD) or flash memory. The GNSS receiver 51 identifies the position of the vehicle M based on signals received from GNSS satellites. The position of the vehicle M may be identified or supplemented by an inertial navigation system (INS) that uses the output of the vehicle sensors 40. The navigation HMI 52 includes a display device, a speaker, a touch panel, keys, etc. The navigation HMI 52 may share some or all of the components with the HMI 30 described above. The route determination unit 53 determines, for example, a route (hereinafter, a route on a map) from the position of the vehicle M identified by the GNSS receiver 51 (or any input position) to a destination input by the occupant using the navigation HMI 52, with reference to the first map information 54. The first map information 54 is information that represents road shapes using, for example, links indicating roads and nodes connected by the links. The first map information 54 may also include information such as the curvature radius and curvature of roads (lanes), and POI (Point Of Interest) information. The route on the map is output to the MPU 60. The navigation device 50 may provide route guidance using the navigation HMI 52 based on the route on the map. The navigation device 50 may be realized by, for example, the functions of a terminal device such as a smartphone or tablet device carried by the occupant. The navigation device 50 may transmit the current position and destination to a navigation server via the communication device 20 and obtain a route equivalent to the route on the map from the navigation server.

[0026] The MPU 60 includes, for example, a recommended lane determination unit 61, and stores second map information 62 in a storage device such as an HDD or flash memory. The recommended lane determination unit 61 divides the route on the map provided by the navigation device 50 into a plurality of blocks (for example, by dividing each block into 100 m in the vehicle travel direction), and determines a recommended lane for each block by referring to the second map information 62. The recommended lane determination unit 61 determines, for example, which lane from the left the vehicle should travel in. Furthermore, when there is a branch point on the route on the map, the recommended lane determination unit 61 determines a recommended lane so that the vehicle M can travel on a reasonable route to reach the branch point. The second map information 62 is map information with higher accuracy than the first map information 54. The second map information 62 includes, for example, information on the centers of lanes, or lane boundary information such as road dividing lines, medians, shoulders, curbs, etc. that divide lanes. The second map information 62 may include road information, traffic regulation information, address information (address and postal code), facility information, telephone number information, etc. The second map information 62 may be updated as needed by the communication device 20 communicating with other devices. The first map information 54 and the second map information 62 may be stored in a storage unit within the driving assistance device 100. The first map information 54 and the second map information 62 may be configured as a single piece of map information.

[0027] The driving operators 80 include, for example, a steering wheel 82, an accelerator pedal 84, a brake pedal 86, a turn signal switch, a shift lever, and other operators. The driving operators 80 are fitted with sensors that detect the amount of operation or the presence or absence of operation, and the detection results are output to the driving assistance device 100 or some or all of the driving force output device 200, the braking device 210, and the steering device 220.

[0028] The driving force output device 200 outputs a driving force (torque) to the driving wheels for driving the vehicle M. The driving force output device 200 includes, for example, a combination of an internal combustion engine, an electric motor, a transmission, etc., and an ECU (Electronic Control Unit) that controls these. The ECU controls the above components in accordance with information input from the driving assistance device 100 or information input from the driving operator 80.

[0029] Braking 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 an ECU. The ECU controls the electric motor according to information input from driving assistance device 100 or information input from driving operator 80, so that a brake torque corresponding to the braking operation is output to each wheel. Braking device 210 may include a backup mechanism that transmits hydraulic pressure generated by operation of a brake pedal included in driving operator 80 to the cylinder via a master cylinder. Note that braking device 210 is not limited to the configuration described above, and may also be an electronically controlled hydraulic brake device that controls an actuator according to information input from driving assistance device 100 to transmit hydraulic pressure from a master cylinder to the cylinder.

[0030] The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor applies force to a rack and pinion mechanism to change the direction of the steered wheels. The steering ECU drives the electric motor to change the direction of the steered wheels in accordance with information input from the driving assistance device 100 or information input from the driving operator 80.

[0031] [Driving assistance devices] The driving assistance device 100 includes, for example, a recognition unit 120, a driving control unit 140, an HMI control unit 160, and a storage unit 180. Each of the recognition unit 120, the driving control unit 140, and the HMI control unit 160 is realized by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Furthermore, some or all of these components may be realized by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), a GPU (Graphics Processing Unit), or an SOC (System On Chip), or may be realized by a combination of software and hardware. The program may be stored in advance in a storage device (a storage device having a non-transitory storage medium) such as an HDD or flash memory of the driving assistance device 100, or may be stored in a removable storage medium such as a DVD or CD-ROM, and installed in the HDD or flash memory of the driving assistance device 100 by inserting the storage medium (non-transitory storage medium) into a drive device. The HMI control unit 160 is an example of a "notification control unit."

[0032] For example, the driving force output device 200, the braking device 210, and the steering device 220 are configured internally so that instructions from the driving support device 100 to the driving force output device 200, the braking device 210, and the steering device 220 are executed with priority over detection results from the driving operator 80. Regarding braking, if the braking force based on the operation amount of the brake pedal 86 is greater than the instruction from the driving support device 100, the latter may be executed with priority. Furthermore, communication priority in an in-vehicle local area network (LAN) may be used as a mechanism for executing instructions from the driving support device 100 with priority. Regarding steering, the steering force based on the instruction from the driving support device 100 may be added together with the steering force based on the operation amount of the steering wheel 82 by the driver.

[0033] The storage unit 180 may be realized by the above-mentioned various storage devices, or a solid state drive (SSD), an electrically erasable programmable read only memory (EEPROM), a read only memory (ROM), or a random access memory (RAM). The storage unit 180 stores, for example, a program (e.g., a vehicle control program), information used by components in the driving assistance device 100, and various other information. The storage unit 180 may also store the above-mentioned map information (first map information 54, second map information 62).

[0034] The recognition unit 120 recognizes the surrounding conditions of the vehicle M based on information obtained from map information (first map information 54, second map information 62) based on information detected by the external environment detection device DD and position information of the vehicle M acquired by the vehicle sensor 40, etc. For example, the recognition unit 120 recognizes the position, speed, acceleration, and other status of objects present in the vicinity (e.g., within a predetermined distance from the vehicle M). Examples of objects include other vehicles, bicycles, pedestrians, etc. The position of an object is recognized as a position on an absolute coordinate system with a representative point of the vehicle M (e.g., the center of gravity or the center of the drive shaft) as the origin, and is used for control. The position of an 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 an area. The "state" of an object may include the acceleration or jerk of the object, or the "behavioral state" (e.g., whether or not the object is changing lanes or is about to change lanes). The recognition unit 120 also recognizes the relative position and relative speed of the object.

[0035] The recognition unit 120 also recognizes the shape of lanes around the vehicle M. For example, the recognition unit 120 recognizes the shape and type of the lane (driving lane) on which the vehicle M is traveling and adjacent lanes adjacent to the driving lane based on the detection results of the external environment detection device DD. For example, the recognition unit 120 performs known image analysis processing, such as edge extraction and feature extraction, on the image captured by the camera 10, and recognizes areas defined by road dividing lines on the left and right sides of the vehicle M as driving lanes based on the analysis processing results. Furthermore, the recognition unit 120 recognizes adjacent lanes based on road dividing lines extending parallel to the road dividing lines (within a predetermined tolerance range). The recognition unit 120 may also recognize the shape and type of lanes based on the positions of objects such as curbs and medians detected by the radar device 12, the LIDAR 14, etc., or may combine these recognition results. Furthermore, the recognition unit 120 may recognize the radius of curvature based on the shapes of the recognized lane and road dividing lines, or may recognize a road as a curved road if the radius of curvature is less than a threshold. The radius of curvature may be replaced with the curvature. The same applies to the following description.

[0036] Furthermore, the recognition unit 120 may refer to map information based on the position information of the vehicle M recognized by the vehicle sensor 40, and recognize the positions and shapes of lanes, the driving lane, and adjacent lanes existing around the vehicle M. Furthermore, the recognition unit 120 recognizes the radius of curvature of the driving lane of the vehicle M from the map information.

[0037] In addition, the recognition unit 120 may perform character recognition on the image captured by the camera 10 to recognize the speed limit (legal speed) of the driving lane from road signs, etc., or may recognize the speed limit of the driving lane from map information.

[0038] The driving control unit 140 controls the driving of the vehicle M based on the surrounding conditions of the vehicle M recognized by the recognition unit 120. For example, the driving control unit 140 executes driving control that controls at least one of the steering and speed of the vehicle M based on the surrounding conditions. The driving control includes, but is not limited to, control using various functions such as cruise control, adaptive cruise control (ACC), lane keeping assistance system (LKAS), and collision mitigation braking system (CMBS). Furthermore, the driving control unit 140 may execute multiple driving controls in parallel.

[0039] Cruise control is a function that controls the speed of vehicle M to approach a target speed when vehicle M is traveling at a constant speed, without the driver having to depress the accelerator pedal. ACC is a function that controls the speed of vehicle M so that vehicle M can follow a preceding vehicle while maintaining a distance within a predetermined range. LKAS is a function that controls the steering of vehicle M so that vehicle M does not deviate from its lane. CMBS is a function that controls deceleration of vehicle M when it is determined that vehicle M may approach or come into contact with an object. Note that the above-mentioned driving controls may be switched on or off by the driver operating a selector switch or the like on the HMI 30, for example, or may be switched depending on the driving conditions. Furthermore, the driving control unit 140 may control the driving of vehicle M by the driver operating the driving operator 80.

[0040] The driving control unit 140 also includes, for example, a target speed setting unit 142, a speed control unit 144, and a steering control unit 146. The target speed setting unit 142 sets a target speed that serves as a reference for the speed of the vehicle M, for example, during operation of driving control such as cruise control. For example, the target speed setting unit 142 may set the target speed based on the speed limit of the lane in which the vehicle M is traveling, or may set the target lane based on vehicle speed information set by the driver of the vehicle M via the HMI 30. Note that when set by the driver, setting within a range between an upper limit and a lower limit according to the speed limit of the lane in which the vehicle M is traveling is permitted. The target speed setting unit 142 may also set (adjust) the target speed based on the speed of another vehicle (for example, a preceding vehicle) or the radius of curvature if the lane in which the vehicle M is traveling is a curved road.

[0041] For example, when a driving control such as cruise control is in operation, the speed control unit 144 controls the speed of the vehicle M so that the vehicle M approaches a target speed. Furthermore, when the ACC function is in operation, the speed control unit 144 controls the acceleration / deceleration of the vehicle M so that the vehicle M follows the preceding vehicle at a predetermined distance.

[0042] The steering control unit 146 performs steering control so that the vehicle M does not deviate from the driving lane (for example, so that the vehicle M travels in the center of the lane) while driving control such as LKAS is in operation. In addition, the speed control unit 144 and the steering control unit 146 perform speed control and steering control to avoid contact between the vehicle M and an object.

[0043] The HMI control unit 160 notifies the occupants of the vehicle M of predetermined information via the HMI 30. The predetermined information includes, for example, information related to the driving of the vehicle M, such as information about the state of the vehicle M and information about driving control. The information about the state of the vehicle M includes, for example, the speed of the vehicle M, engine RPM, shift position, etc. The information about driving control includes, for example, the type of driving control currently in operation, the reason for operation, and the operating status. The information about driving control may also include information about a warning (attention) to the driver. The predetermined information may also include information about the current location and destination of the vehicle M, the remaining amount of fuel, etc., and may also include information unrelated to driving control of the vehicle M, such as television programs, content (e.g., movies) stored on a storage medium such as a DVD, etc.

[0044] For example, the HMI control unit 160 may generate an image including the above-described predetermined information and display the generated image on the display unit of the HMI 30, or may generate sound indicating the predetermined information and output the generated sound from a speaker of the HMI 30. The timing at which the sound is output may be, for example, when driving control is started or stopped (ended), when the displayed image is switched, or when the vehicle M reaches a predetermined state. Furthermore, the HMI control unit 160 may output information received by the HMI 30 to the driving control unit 140, etc.

[0045] [Travel control unit] Next, the function of the driving control unit 140 in the embodiment will be described in detail. In the following, speed control near a curved road while cruise control is operating will be described as an example. FIG. 2 is a diagram for explaining a scene in which a vehicle M is driving near a curved road. In the example of FIG. 2, the vehicle M is driving at a speed VM in a lane L1 defined by road dividing lines LN1 and LN2. In the example of FIG. 2, a curved road exists in the traveling direction of the vehicle M (within a predetermined distance). The example of FIG. 2 also shows a change in speed relative to the traveling position of the vehicle M.

[0046] For example, when cruise control is in operation on a straight road section (the section from points X1 to X2 shown in FIG. 2), the driving control unit 140 controls the speed VM of the vehicle M so that it falls within a predetermined speed range from the target speed (e.g., target speed TS1) set by the target speed setting unit 142. For example, when the speed limit of the lane L1 is 80 km / h, the target speed setting unit 142 sets the target speed TS1 to a speed around 80 km / h, and the speed control unit 144 executes speed control so that the relative speed between the speed VM of the vehicle M and the target speed TS1 falls within a predetermined range (e.g., ±5 km). The target speed may be set under predetermined conditions by an input operation by the occupant. When LKAS control is in operation in addition to (or instead of) cruise control, the steering control unit 146 executes steering control so that the vehicle M travels along a route K1 in the center of the lane L1.

[0047] Here, when the recognition unit 120 recognizes that a curved road (curved road section) exists within a predetermined distance ahead (in the traveling direction) of the vehicle M, the target speed setting unit 142 adjusts the target speed of the vehicle M. In this case, the target speed setting unit 142 sets a target speed TS2 that is smaller than the target speed TS1 for traveling on a straight road section, for example, in accordance with the smallest radius of curvature of the curved road in the section of the curved road that can be recognized by the camera 10. For example, the target speed setting unit 142 sets a smaller target speed TS2 the smaller the radius of curvature (the larger the curvature). Then, when the vehicle M actually travels on a curved road, the speed control unit 144 executes speed control so that the relative speed between the speed VM of the vehicle M and the target speed TS2 falls within a predetermined range. In the example of FIG. 2, the speed is controlled so that the relative speed falls within a predetermined range near the entrance to the curved road (point X2 shown in FIG. 2), and that speed is maintained until the vehicle M passes through the curved road. When the vehicle M is traveling on a curved road, the target speed setting unit 142 may acquire the yaw rate or steering angle of the vehicle M from the vehicle sensor 40, adjust the target speed TS2 at a predetermined timing (or a predetermined cycle) according to the acquired yaw rate or steering angle, and perform speed control of the vehicle M according to the adjusted target speed TS2. Since the attitude of the vehicle M can be recognized from the yaw rate or steering angle, it is possible to adjust the target speed to a more appropriate one according to the current situation (attitude, etc.) of the vehicle M.

[0048] Furthermore, when the vehicle passes through a curved road (when passing point X3 at the curved road exit shown in FIG. 2), the driving control unit 140 sets a new target speed based on the surrounding conditions recognized by the recognition unit 120, and performs driving control based on the set target speed. Note that when an object such as another vehicle is present around the vehicle M, the driving control unit 140 performs speed control and steering control to avoid contact with the object, and issues a warning (notification) to the occupant via the HMI control unit 160.

[0049] Here, methods for setting the target speed when a curved road is recognized include a method of setting the target speed (first target speed) according to the radius of curvature (first radius of curvature) obtained based on the detection results of an external detection device DD such as camera 10 or the yaw rate (or steering angle) of the vehicle M, and a method of referring to map information based on the position information of the vehicle M, obtaining the radius of curvature (second radius of curvature) of the lane corresponding to the position information from the map information, and setting the target speed (second target speed) according to the obtained second radius of curvature.

[0050] In the case of map information, there may be an error with respect to the actual radius of curvature, or the map information may not be the latest information and may therefore differ from the actual radius of curvature. Therefore, the target speed setting unit 142 sets the second target speed set according to the radius of curvature stored in the map information to be smaller than the first target speed set according to the radius of curvature derived from the detection result of the external environment detection device DD or the yaw rate (or steering angle) of the vehicle M, even if the radius of curvature is the same.

[0051] FIG. 3 is a diagram showing an example of a target speed relative to the radius of curvature of a driving lane. In the example of FIG. 3, the horizontal axis indicates the radius of curvature R of the driving lane, and the vertical axis indicates the target speed of the vehicle M set by the target speed setting unit 142. The target speed increases as the radius of curvature R increases, but as shown in FIG. 3, a first target speed is set higher than a second target speed. Therefore, as shown in FIG. 2, the speed change on the driving road also differs between the first target speed and the second target speed. Note that the information shown in FIG. 3 is stored, for example, in the storage unit 180, and is referenced when setting the target speed.

[0052] After setting the first target speed and the second target speed, the speed control unit 144 selects one of the first target speed and the second target speed and controls the speed of the vehicle M based on the selected target speed. FIG. 4 is a diagram for explaining the difference between the speed control of the vehicle M based on the first target speed and the second target speed set for the same radius of curvature. In the example of FIG. 4, the horizontal axis represents the distance from point X1 to point X3, and the vertical axis represents the speed VM of the vehicle M. As shown in FIG. 4, when the vehicle M travels between points X1 and X3, the speed VM of the vehicle M changes in a state where it is higher when the first target speed is set than when the second target speed is set.

[0053] 3, when there is a difference between the respective target speeds that is equal to or greater than a predetermined value, the speed control unit 144 selects the smaller target speed of the first target speed or the second target speed (low select control), and executes speed control so that the relative speed of the speed VM of the vehicle M with respect to the selected target speed becomes less than the predetermined speed. This makes it possible to prevent the vehicle M from exceeding the speed limit when traveling on a curved road, thereby realizing safer traveling control.

[0054] Here, since the radius of curvature for setting the first target speed is recognized by a camera image or the like, the recognized radius of curvature may change significantly (different from the actual radius of curvature) because the attitude of the vehicle M relative to the driving lane changes due to, for example, a steering operation by the driver (e.g., steering further or steering back). Therefore, as shown in FIG. 3, even if the second radius of curvature based on map information is R1, the value of the first radius of curvature acquired based on the detection result of the external environment detection device DD such as the camera 10 or the yaw rate (or steering angle) of the vehicle M may change to R2 or R3. For example, when the first radius of curvature is determined to be R3 (R1 or more), a second target speed TSa that is a target speed smaller than the first target speed TSb is set, but when the first radius of curvature is less than R1 (e.g., when the first radius of curvature is determined to be R2), a first target speed TSc that is smaller than the second target speed TSa is selected. Therefore, when the driver performs steering operations on a curved road, the first target speed and the second target speed, which serve as the reference, may change frequently, and as a result, the target speed that serves as the reference for speed control as shown in Figure 4 may also change, which may cause the speed control to become unstable (the speed VM of the vehicle M may fluctuate).

[0055] Therefore, when a curved road is present in the traveling direction of the vehicle M, the target speed setting unit 142 sets a new target speed using information on both the first target speed and the second target speed, so that a target speed with little difference can be set. This makes it possible to suppress fluctuations in the speed VM when traveling on a curved road.

[0056] For example, the target speed setting unit 142 multiplies both the first target speed and the second target speed by a value based on a corresponding predetermined transition ratio α, and adds the multiplication results to adjust the target speed. Specifically, the target speed setting unit 142 calculates the target speed based on the following equation (1). Target speed = (1st target speed) × α + (2nd target speed) × (1-α)…(1)

[0057] In the above formula (1), the transition ratio α is set, for example, according to the traveling conditions of the vehicle M. For example, the transition ratio α is set according to the relative speed ΔV between the target speed for the minimum curvature radius Rmin within the detection range of the curved road and the speed VM of the vehicle M. For example, when the relative speed ΔV transitions from 30 [km / h] to 0 [km / h], the transition ratio α transitions from 0 to 1 according to the transition. Therefore, if the relative speed ΔV is large, the value multiplied by the first target speed becomes small, and the value multiplied by the second target speed becomes relatively large. Note that the numerical values ​​are merely examples and are not limited to these.

[0058] For example, when using equation (1), immediately after the vehicle M recognizes a curved road (for example, near point X1 shown in FIG. 2), the target speed switches from target speed TS1 to target speed TS2 in accordance with the curved road, and the relative speed ΔV at this time becomes large (the transition ratio α approaches 0). Therefore, for the target speed when traveling in this vicinity, the ratio to the second target speed (the value related to the ratio by multiplication in equation (1)) becomes larger than the value to the first target speed. As a result, a target speed is set in which the second target speed has a higher priority (greater influence) than the first target speed. As a result, when the relative speed ΔV is large, the value of the second target speed based on map information in which there is no speed change due to steering operation or the like (the amount of speed change is small) can be given priority, thereby enabling more stable speed control.

[0059] Furthermore, speed control is executed, and as shown in FIG. 2, the relative speed ΔV between the speed VM of the vehicle M and the target speed becomes smaller as the vehicle approaches the curved road (the speed VM of the vehicle M approaches the target speed, or the transition ratio α approaches 1). Therefore, a target speed is set that has a large ratio (greater influence) to the first target speed and a small ratio (smaller influence) to the second target speed. Therefore, according to the example of FIG. 2, while traveling on the curved road (points X2 to X3), the relative speed ΔV is small, so a target speed is set that is heavily influenced by the first target speed (the first target speed is prioritized). As a result, when the relative speed ΔV is small, speed control is executed according to the first target speed set based on the detection result of the external environment detection device DD.

[0060] In this way, in the embodiment, when traveling near a curved road, the target speed is set by combining the first target speed and the second target speed at a predetermined ratio according to the traveling conditions of the vehicle M, thereby suppressing changes in the target speed caused by switching between the first target speed and the second target speed in response to the radius of curvature of the curved road. Furthermore, since fluctuations in the target speed can be suppressed, it is possible to suppress speed control that does not correspond to the surrounding conditions, which would be caused by setting an arbitrarily small target speed using only the target speed based on map information.

[0061] 5 is a diagram for explaining a speed change of the vehicle M based on the adjusted target speed. The target speed setting unit 142 executes speed control prioritizing the second target speed before the curved road and executes speed control prioritizing the first target speed on the curved road based on the first target speed, the second target speed, and the transition ratio α, thereby smoothly changing the speed. Therefore, the adjusted target speed can suppress fluctuations in the speed change, and more appropriate speed control can be achieved.

[0062] [Processing flow] Fig. 6 is a flowchart showing an example of processing executed by the driving assistance device 100 in the embodiment. In the example of Fig. 6, the speed control processing related to cruise control will be mainly described among the processing executed by the driving assistance device 100. The processing of Fig. 6 may be repeatedly executed at a predetermined timing or at a predetermined cycle while the cruise control is being executed, for example.

[0063] 6, the target speed setting unit 142 sets a first target speed based on the detection result of the external environment detection device DD (step S100). In the processing of step S100, the target speed setting unit 142, for example, acquires the curvature radius of the lane on which the vehicle M is traveling based on the detection result of the external environment detection device DD, and sets a first target speed according to the acquired curvature radius. Next, the target speed setting unit 142 refers to map information based on the position information of the vehicle M, and sets a second target speed based on the map information (step S110). In the processing of step S110, the target speed setting unit 142, for example, acquires the curvature radius of the lane on which the vehicle M is traveling from the map information, and sets a second target speed according to the acquired curvature radius.

[0064] Next, the speed control unit 144 determines whether or not a curved road (a road with a curvature radius less than a threshold) exists in the traveling direction of the vehicle M (step S120). If it is determined that a curved road does not exist, the speed control unit 144 selects one of a first target speed and a second target speed (step S130) and controls the speed VM of the vehicle M based on the selected target speed (step S140). Furthermore, if it is determined in the processing of step S120 that a curved road exists in the traveling direction of the vehicle M, the target speed setting unit 142 sets a target speed that combines the first target speed and the second target speed at a ratio according to the traveling situation of the vehicle M (step S150). In the processing of step S150, the target speed setting unit 142 calculates the target speed using, for example, the above-mentioned formula (1). Next, the speed control unit 144 controls the speed of the vehicle M based on the set target speed (step S160). This ends the processing of this flowchart.

[0065] [Variations] In the embodiment, instead of (or in addition to) a case where a curved road is present in the traveling direction of the vehicle M, if the occupant selects via the HMI 30 to perform control to set a target speed that combines the first target speed and the second target speed, the above-described setting of the target speed may be executed regardless of whether a curved road is present. In this case, when performing predetermined driving control such as cruise control, the HMI control unit 160 may output inquiry information to the HMI 30 to inquire about the control content to the occupant, and perform switching control based on the result of the inquiry.

[0066] Furthermore, when the target speed setting unit 142 cannot recognize the driving lane (curvature radius) from the detection results of the external environment detection device DD (or when it is determined that the recognition accuracy of road dividing line marks has decreased) based on the surrounding conditions of the vehicle M, such as the weather and the presence of surrounding vehicles, it is not necessary to perform the process of setting the target speed by combining the first target speed and the second target speed, even if there is a curved road in the traveling direction of the vehicle M. In this case, the target speed setting unit 142 controls the speed VM of the vehicle M based on the second target speed based on map information, or terminates cruise control. This allows for appropriate control according to the vehicle conditions. The above-mentioned radius of curvature may be replaced with curvature, in which case the magnitude relationship (determination conditions, etc.) in the control may be reversed or otherwise modified as appropriate.

[0067] As described above, according to the embodiment, the vehicle control program causes a computer to recognize the surrounding conditions of the vehicle M based on the detection results of the external environment detection device DD, set a first target speed of the vehicle M based on the surrounding conditions, set a second target speed of the vehicle M based on map information, select one of the first target speed and the second target speed, and control the speed of the vehicle M based on the selected target speed. When a curved road is present in the traveling direction of the vehicle M, the target speed is set by combining the first target speed and the second target speed in a ratio according to the traveling conditions of the vehicle, and the speed of the vehicle is controlled based on the set target speed, thereby making it possible to set a more appropriate target speed even on a curved road. Therefore, more appropriate speed control can be achieved, for example, when performing driving control such as cruise control.

[0068] Specifically, according to the embodiment, the curvature radius (or curvature) of the curved road is obtained from the recognition result by the external environment detection device DD and from map information, and a target speed is set for each of the obtained curvature radii. If there is a difference between the two target speeds, one of them is selected to adjust the vehicle speed. In this control, if the relative speed between the target speed and the vehicle speed is large, the target speed is adjusted so that the influence of the target speed using the map information is greater (priority is given to the target speed). As a result, for example, in speed control before entering a curve or while traveling, a target speed with little fluctuation based on the map information is set, thereby suppressing speed fluctuations. Furthermore, according to the embodiment, if there is a difference between the two target speeds, the lower vehicle speed is selected, thereby suppressing speeding on curved roads.

[0069] Furthermore, according to the embodiment, when the relative speed is low, the target speed is adjusted so that the influence of the target speed set based on the recognition result by the external environment detection device DD is large, and the influence of the target speed based on the map information is adjusted so that the influence of the target speed is small. In this way, when the speed is close to the target speed, the recognition result by the external environment detection device DD is used to realize more appropriate driving control for the actual surrounding conditions. Furthermore, according to the embodiment, before entering a curve, speed control is performed based on highly accurate map information, and after entering the curve, the difference between the target speed based on the surrounding recognition and the target speed is reduced, thereby suppressing fluctuations in the speed VM of the vehicle M and realizing more stable speed control.

[0070] The above-described embodiment can be expressed as follows. a storage medium for storing computer-readable instructions; a processor connected to the storage medium; The processor executes the computer-readable instructions to: The vehicle recognizes the surrounding situation based on the detection results of the external detection device, setting a first target speed of the vehicle based on the surrounding conditions; setting a second target speed of the vehicle based on map information; selecting one of the first target speed and the second target speed, and controlling the speed of the vehicle based on the selected target speed; When a curved road is present in the traveling direction of the vehicle, a target speed is set by combining the first target speed and the second target speed at a ratio according to the traveling situation of the vehicle; controlling the speed of the vehicle based on the set target speed; Vehicle control device.

[0071] The above describes the form for carrying out the present invention using an embodiment, but the present invention is not limited to such an embodiment, and various modifications and substitutions can be made within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0072] 10...camera, 12...radar device, 14...LIDAR, 16...object recognition device, 20...communication device, 30...HMI, 40...vehicle sensor, 50...navigation device, 60...MPU, 80...driving operator, 100...driving assistance device, 120...recognition unit, 140...travel control unit, 142...target speed setting unit, 144...speed control unit, 146...steering control unit, 160...HMI control unit, 180...memory unit, 200...traveling drive force output device, 210...brake device, 220...steering device, M...vehicle

Claims

1. On the computer, Recognizing the surrounding situation of the vehicle based on the detection results of the external detection device; setting a first target speed of the vehicle based on the surrounding conditions; setting a second target speed of the vehicle based on map information; selecting one of the first target speed and the second target speed, and controlling the speed of the vehicle based on the selected target speed; When a curved road is present in the traveling direction of the vehicle, a target speed is set by combining the first target speed and the second target speed at a ratio according to the traveling situation of the vehicle, and the speed of the vehicle is controlled based on the set target speed. Vehicle control program.

2. When the relative speed between the target speed and the speed of the vehicle is large, the ratio of the second target speed is increased. The vehicle control program according to claim 1 .

3. When the relative speed between the target speed and the speed of the vehicle is large, the ratio of the smaller target speed between the first target speed and the second target speed is increased. The vehicle control program according to claim 1 .

4. setting the first target speed and the second target speed in accordance with the radius of curvature or the curvature of the curved road; The vehicle control program according to claim 1 .

5. adjusting the first target speed based on a yaw rate or a steering angle of the vehicle; 5. The vehicle control program according to claim 4.

6. a recognition unit that recognizes the surrounding situation of the vehicle based on the detection results of the external environment detection device; a target speed setting unit that sets a first target speed of the vehicle based on the surrounding conditions recognized by the recognition unit, and sets a second target speed of the vehicle based on map information; a speed control unit that selects one of the first target speed and the second target speed and controls the speed of the vehicle based on the selected target speed, the target speed setting unit sets a target speed by combining the first target speed and the second target speed at a ratio according to a traveling situation of the vehicle when a curved road is present in a traveling direction of the vehicle; The speed control unit controls the speed of the vehicle based on the set target speed. Vehicle control device.

7. The computer The vehicle recognizes the surrounding situation based on the detection results of the external detection device, setting a first target speed of the vehicle based on the surrounding conditions; setting a second target speed of the vehicle based on map information; selecting one of the first target speed and the second target speed, and controlling the speed of the vehicle based on the selected target speed; When a curved road is present in the traveling direction of the vehicle, a target speed is set by combining the first target speed and the second target speed at a ratio according to the traveling situation of the vehicle; controlling the speed of the vehicle based on the set target speed; Vehicle control method.

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