Vehicle travel control device

Abstract

To provide a vehicle travel control device capable of preventing a passenger from feeling anxious when a vehicle travels on a curve section under automatic driving.SOLUTION: In a travel control device 10 for a vehicle 1 capable of performing automatic driving, a target speed calculation section 34: sets a target speed to a first speed V1 so that lateral acceleration of the vehicle 1 becomes equal to or lower than a predetermined value G1 when the vehicle 1 performs automatic travel on a travel route; sets the target speed for a curve section to a second speed V2 which is lower than the first speed V1 when the curve section exists on the travel route; and sets the target speed for the curve section with an oncoming vehicle 2 to a third speed V3 which is lower than the second speed V2 when the oncoming vehicle 2 exists on the curve section.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a driving control device for a vehicle capable of performing autonomous driving. [Background technology]

[0002] Vehicles that can run autonomously under the control of an automatic driving device are being developed. In vehicles that run autonomously equivalent to SAE (Society of Automotive Engineers) levels 3 to 5, the automatic driving device takes the lead in controlling the vehicle according to the level of autonomous driving. Therefore, even when driving on curved sections, the driver basically does not need to perform any driving operations. When driving on curved sections using automatic driving, there are cases where the vehicle's speed is controlled so that it runs at the same speed as on a straight road, and cases where the speed is controlled so that it runs on curved sections at a different speed than on a straight road.

[0003] As an example of speed control for an autonomous vehicle on a curved section, Patent Document 1 discloses a vehicle control device that sets a target vehicle speed for turning on a curved road and sets a target acceleration for achieving the target vehicle speed, taking into consideration the distance to the vehicle ahead and the turning radius of the curved road, etc. The device in Patent Document 1 suppresses car sickness in occupants by turning at a nearly constant acceleration from the start to the end of the turning. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-066383 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, in a vehicle that performs automatic driving equivalent to levels 3 to 5, the automatic driving device of the vehicle mainly controls the vehicle, so the driver does not basically need to drive the vehicle during automatic driving, and even if the driver sits in the driver's seat, he or she is riding as a passenger, not a driver. Passengers riding in the vehicle during automatic driving tend to feel uncomfortable or anxious if the behavior of the vehicle during automatic driving differs from the behavior when the driver is driving the vehicle. In particular, when the vehicle is traveling in a curved section, passengers tend to feel anxious about whether the automatic driving device is properly controlling the vehicle, and this anxiety is affected by the external environment of the curved section. In particular, the anxiety increases when passing an oncoming vehicle in a curved section.

[0006] The present invention has been made in consideration of the above-described situation, and its purpose is to provide a vehicle driving control device that can reduce the anxiety of passengers when driving through curved sections while autonomously driving. [Means for solving the problem]

[0007] According to one aspect of the present invention, a driving control device for a vehicle capable of autonomous driving includes an environmental state acquisition unit that acquires information regarding a vehicle state and a surrounding environment of the vehicle, a route generation unit that generates a driving route during autonomous driving based on the information acquired by the environmental state acquisition unit, a curve detection unit that detects a curve section present on the driving route based on the information acquired by the environmental state acquisition unit, an oncoming vehicle detection unit that detects whether an oncoming vehicle is present in an oncoming lane in the curve section, a target speed calculation unit that calculates a target speed when the vehicle is autonomously driving according to the driving route generated by the route generation unit, and and a vehicle control unit that controls the speed of the vehicle so that it travels along the travel route at a target speed, wherein the target speed calculation unit sets a first vehicle speed as the target speed so that the lateral acceleration of the vehicle is equal to or less than a predetermined value when the vehicle is autonomously travelling along the travel route, and when a curve section is present in the travel route, the target speed calculation unit sets the target speed in the curve section to a second vehicle speed that is smaller than the first vehicle speed, and when an oncoming vehicle is present in the curve section, the target speed calculation unit sets the target speed in the curve section where the oncoming vehicle is present to a third vehicle speed that is smaller than the second vehicle speed. Effect of the Invention

[0008] The vehicle driving control device according to the present invention can reduce the sense of anxiety felt by passengers when the vehicle is traveling through curved sections while being driven autonomously. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration of a vehicle cruise control device according to a first embodiment of the present invention. [Diagram 2] 2(a) and (b) are diagrams showing schematic diagrams of curved sections. [Diagram 3] FIG. 3 is a flowchart illustrating the flow of speed control in the first embodiment. [Figure 4]FIG. 4 is a flowchart illustrating the flow of speed control in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] -First embodiment- Hereinafter, a vehicle driving control device according to a first embodiment of the present invention will be described in detail with reference to the drawings. The vehicle driving control device according to this embodiment is configured to recognize the vehicle's position and the surrounding environment of the vehicle using external sensors such as a radar and a camera, and to control the vehicle speed and steering to perform automatic driving.

[0011] Fig. 1 is a block diagram showing a schematic configuration of a vehicle cruise control device in the first embodiment, and Fig. 2(a) and (b) are diagrams showing a curve section on which the vehicle travels. The cruise control device 10 of the vehicle 1 includes an external sensor 21 for detecting the environment around the vehicle, an internal sensor 22 for detecting the vehicle state including the motion state, a positioning device 23 such as a global navigation satellite system (GNSS), a map information database 24, a V2X unit 25, an automatic driving controller 30, and a driving module 50. In this embodiment, automatic driving of the vehicle 1 on a general road is assumed, but this embodiment can also be applied to roads other than general roads such as expressways.

[0012] The external environment sensor 21 is composed of a plurality of detection means for detecting, as external environment data such as image data or point cloud data, dividing lines on the road that define the lane in which the vehicle 1 is traveling and adjacent lanes, and the presence and relative distances of obstacles such as other vehicles and objects around the vehicle 1. Here, other vehicles include oncoming vehicles traveling in the oncoming lane.

[0013] The external sensor 21 includes, for example, a plurality of cameras that capture images of the front and rear areas of the vehicle 1 using image sensors, a millimeter wave radar that transmits radio waves to the front area of ​​the vehicle 1 to detect obstacles, and a LiDAR that irradiates the front and rear areas of the vehicle with laser light to measure the distance and direction to an obstacle. Note that the external sensor 21 is not limited to the above-mentioned detection means, and may be configured to cover 360 degrees around the vehicle 1 and detect the positions and distances of obstacles, etc. within a predetermined range in the front, rear, left and right directions of the vehicle 1, and the positions of the dividing lines of the vehicle's own lane and adjacent lanes.

[0014] The internal sensor 22 is composed of a plurality of detection means for measuring physical quantities representing the motion state of the vehicle 1. The internal sensor 22 includes, for example, a vehicle speed sensor for detecting the speed of the vehicle 1, a lateral acceleration sensor for detecting the acceleration in the vehicle width direction of the vehicle 1, i.e., the lateral acceleration, a yaw rate sensor for detecting the yaw rate of the vehicle 1, an acceleration sensor for detecting the acceleration in the longitudinal direction of the vehicle 1, and the like.

[0015] The external sensor 21 and the internal sensor 22 are configured to start operating simultaneously when the vehicle 1 is started, and to constantly detect the surrounding environment and vehicle state of the vehicle 1 and transmit the information to the automatic driving controller 30.

[0016] The positioning device 23 is configured to receive radio waves from GNSS satellites and acquire current position information such as the latitude and longitude of the vehicle 1. The map information database 24 is a storage device that stores map information such as a three-dimensional high-precision map. The map information database 24 stores, for example, information on speed limits set by road types or road signs, information on road shapes such as curvature, gradient, and number of lanes, and information on obstacles such as guardrails and side walls along the road, in association with road position information. The current position information acquired by the positioning device 23 and the map information in the map information database 24 are input to the automatic driving controller 30.

[0017] The V2X unit 25 is configured to receive sensing information around the vehicle by V2X communication. V2X (Vehicle to Everything) is a wireless communication technology that connects a vehicle to everything, and is a collective term for communication between vehicles (V2V: Vehicle to Vehicle), communication between a vehicle and roadside infrastructure (V2I: Vehicle to Infrastructure), communication between a vehicle and a pedestrian (V2P: Vehicle to Pedestrian), and communication between a vehicle and a network (V2N: Vehicle to Network). The sensing information around the vehicle acquired by V2X communication includes information about oncoming vehicles traveling in the oncoming lane.

[0018] The autonomous driving controller 30 is configured, for example, by a computer including a ROM that stores programs and data, a CPU that performs arithmetic processing, a RAM that stores dynamic data and arithmetic processing results, an input / output interface, etc. The autonomous driving controller 30 is configured to execute the functions of an environmental state acquisition unit 31, a route generation unit 32, a curve detection unit 33, a target speed calculation unit 34, a vehicle control unit 35, and an oncoming vehicle detection unit 36, and to control the entire driving control device 10 of the vehicle 1.

[0019] The environmental state acquisition unit 31 is configured to acquire information on the vehicle state and the surrounding environment of the vehicle 1. For example, the environmental state acquisition unit 31 estimates the absolute position of the vehicle 1 (the vehicle's own position) by matching the position information of the vehicle 1 input from the positioning device 23 with the map information input from the map information database 24. The environmental state acquisition unit 31 estimates the positions of the dividing lines between the own lane and adjacent lanes, the positions and speeds of other vehicles including oncoming vehicles, and the like, based on external data such as image data and point cloud data input from the external sensor 21.

[0020] Furthermore, the environmental state acquisition unit 31 acquires the vehicle state including the motion state of the vehicle 1 based on the internal data input from the internal sensor 22. Note that the environmental state acquisition unit 31 can be configured to determine the relative position of the vehicle 1 with respect to the dividing line between the adjacent lane based on the external data input from the external sensor 21, instead of estimating the absolute position of the vehicle 1 by matching the position information of the vehicle 1 with map information. Furthermore, information on obstacles such as guardrails and side walls existing along the road may be acquired by the environmental state acquisition unit 31 based on the external data input from the external sensor 21 instead of or in addition to storing it in the map information database 24.

[0021] The route generation unit 32 is configured to generate a driving route during autonomous driving based on the information acquired by the environmental state acquisition unit 31. Specifically, the route generation unit 32 generates a driving route for the vehicle 1 to travel from the vehicle position of the vehicle 1 estimated by the environmental state acquisition unit 31 to a destination of autonomous driving.

[0022] The curve detection unit 33 detects curve sections that exist on the driving route generated by the route generation unit 32. For example, the curve detection unit 33 detects whether or not a curve section exists on the driving route based on information on the road shape input from the map information database 24. The curve sections will be described later.

[0023] The oncoming vehicle detection unit 36 ​​detects an oncoming vehicle present in a curve section during autonomous driving. Here, the oncoming vehicle is a vehicle traveling in the opposite direction to the traveling direction of the vehicle 1 in the oncoming lane in the curve section. The oncoming vehicle detection unit 36 ​​can detect an oncoming vehicle that is predicted to pass the vehicle 1 in the curve section before the vehicle 1 enters the curve section and while the vehicle 1 is traveling in the curve section. In other words, the oncoming vehicle detection unit 36 ​​is configured to predict the occurrence of passing between the vehicle 1 and an oncoming vehicle in the curve section.

[0024] For example, the oncoming vehicle detection unit 36 ​​detects whether or not there is an oncoming vehicle traveling in the opposite direction to the traveling direction of the vehicle 1 in the oncoming lane in a curved section, based on external data such as image data and point cloud data input from the external sensor 21. Alternatively or in addition, the oncoming vehicle detection unit 36 ​​may detect the presence of an oncoming vehicle traveling in the oncoming lane in a curved section, based on oncoming vehicle information acquired from the V2X unit 25. The oncoming vehicle information acquired from the V2X unit 25 is useful in an environment in which it is difficult for the external sensor 21 to capture an oncoming vehicle due to, for example, the curvature of the road or the influence of an obstacle.

[0025] The target speed calculation unit 34 is configured to calculate a target speed when the vehicle 1 travels in an autonomous driving manner according to the travel route generated by the route generation unit 32. For example, the target speed calculation unit 34 calculates the target speed so that the vehicle speed is equal to or less than the speed limit of the road and based on the set speed during autonomous driving selected by the user. Specifically, the target speed calculation unit 34 calculates the target speed so that the lateral acceleration of the vehicle 1 traveling in accordance with the travel route is equal to or less than a predetermined value G1, which is equal to or less than the speed limit of the road and the speed set by the user. In addition, the target steering angle when the vehicle 1 travels in an autonomous driving manner according to the travel route generated by the route generation unit 32 is also calculated.

[0026] Here, the predetermined value G1 of the lateral acceleration is set to a value that prevents the vehicle 1 from skidding when traveling on a curved section. The lateral acceleration A when the vehicle 1 travels at a constant vehicle speed V and a constant steering angle without skidding is expressed as A=V based on the radius of curvature R of the travel route and the vehicle speed V. 2 Based on the radius of curvature R of the travel route acquired from the road information in the map information database 24, the target speed calculation unit 34 calculates the vehicle speed V at which the lateral acceleration is equal to or smaller than a predetermined value G1 (for example, G1=0.3 G) as the basic target speed V1 of the vehicle 1 traveling along the travel route.

[0027] The vehicle control unit 35 transmits a drive command to the traveling module 50 so that the vehicle 1 travels at the target speed and target steering angle calculated by the target speed calculation unit 34 according to the travel route generated by the route generation unit 32, and controls the longitudinal and lateral movements of the vehicle 1. For example, the vehicle control unit 35 calculates the yaw rate γ and lateral acceleration (d 2 y / dt 2 ) the speed, attitude, and lateral displacement of the vehicle 1 after Δt seconds are estimated from the relationship. The vehicle control unit 35 transmits to the traveling module 50 a steering angle command such that the lateral displacement after Δt seconds is yt, and a speed command such that the speed after Δt seconds is Vt.

[0028] The traveling module 50 includes a traveling actuator, a controller for controlling the traveling actuator, and the like. The traveling actuator includes a steering mechanism 51, a brake 52, and an engine 53. The traveling module 50 controls the driving of the steering mechanism 51, the brake 52, and the engine 53 based on a driving command from the vehicle control unit 35 so that the vehicle 1 travels along the traveling route at a target speed and a target steering angle. The traveling module 50 may be configured to include a traveling motor instead of or in addition to the engine 53. In this case, the vehicle 1 functions as an electric vehicle or a hybrid vehicle.

[0029] When a deceleration command is input from the vehicle control unit 35, the traveling module 50 controls the vehicle speed by controlling the braking force of the brake 52. When an acceleration / deceleration command is input from the vehicle control unit 35, the traveling module 50 controls the vehicle speed by controlling the driving force of the engine 53. In addition, when a steering command is input from the vehicle control unit 35, the traveling module 50 controls the steering mechanism 51 to perform steering control.

[0030] When there is no preceding vehicle, the automatic driving controller 30 controls the vehicle 1 to travel at a constant speed at the above-mentioned target speed. When the preceding vehicle speed is equal to or lower than the target speed and the vehicle 1 catches up with the preceding vehicle, the automatic driving controller 30 controls the vehicle 1 to travel following the preceding vehicle while maintaining a vehicle distance according to a set time gap (inter-vehicle time = vehicle distance / own vehicle speed) in accordance with the preceding vehicle speed. When the preceding vehicle speed is faster than the speed of the vehicle 1 or when the preceding vehicle has disappeared in front of the vehicle 1, the automatic driving controller 30 is configured to accelerate to the target speed at a set acceleration.

[0031] Furthermore, the automatic driving controller 30 detects lane markings and the vehicle's own position using the environmental state acquisition unit 31 based on image data acquired by the external sensor 21, for example, and performs steering control of the vehicle 1 so that the vehicle can travel in the center of the lane. The automatic driving controller 30 can estimate the vehicle's own position (self-position) by various methods and perform steering control so as to follow the travel route. As a method of self-position estimation for route tracking, in addition to white line-based self-position estimation based on lane markings (white lines) detected from image data, self-position estimation by matching point cloud data input from the external sensor 21 with a high-precision map of point clouds or a high-precision map of vector maps obtained from the map information database 24, or self-position estimation using GNSS can also be performed.

[0032] In this way, the automatic driving controller 30 performs automatic driving of the vehicle 1 by combining longitudinal control (speed control, vehicle distance control) and lateral control (steering control, lane keeping control).

[0033] Here, in a vehicle that performs automatic driving equivalent to SAE levels 3 to 5, the automatic driving device of the vehicle, i.e., the automatic driving controller 30, mainly controls the vehicle, so the driver basically does not need to drive the vehicle during automatic driving. Therefore, even if the driver sits in the driver's seat, he or she is riding as a passenger. If the behavior of the vehicle during automatic driving is different from the behavior when the driver operates the vehicle, the passengers who are riding the vehicle during automatic driving tend to feel uncomfortable or anxious. In particular, when the vehicle runs through a curved section, the passengers are likely to feel anxious about whether the automatic driving device is controlling the vehicle appropriately, and this anxiety may be amplified by the external environment of the curved section.

[0034] As for the external environment of the curved section, for example, the presence of an oncoming vehicle in the curved section is thought to affect the passenger's sense of anxiety. Here, the oncoming vehicle is a vehicle traveling in the opposite direction to the traveling direction of the vehicle 1 in the oncoming lane and passing the vehicle 1 in the curved section.

[0035] As an example, consider a curve section where traffic keeps to the left. Figures 2(a) and (b) show a schematic diagram of a right curve section and a left curve section, respectively. The right curve section CA shown in Figure 2(a) can be defined as the section from point C1 to point C2 where the road curves to the right and the curvature of the road is equal to or greater than a predetermined value. The left curve section CB shown in Figure 2(b) can be defined as the section from point C1 to point C2 where the road curves to the left and the curvature of the road is equal to or greater than a predetermined value. Point C1 is the start position of the curve section, and point C2 is the end position of the curve section.

[0036] Alternatively, the curve section may be defined based on the lateral acceleration acting on the vehicle 1. In this case, for example, when the vehicle 1 travels at a speed set by the user that is equal to or lower than the speed limit of the road, a section in which lateral acceleration exceeding a preset value occurs can be defined as the curve section. Here, the preset value of lateral acceleration for defining the curve section may be, for example, the same value as the above-mentioned predetermined value G1 of lateral acceleration, or may be a different value.

[0037] In the following description, the right curve section CA in the left-hand traffic zone shown in Fig. 2(a) may be referred to as an outside curve section where the left lane Cl in which vehicle 1 is traveling is on the outside of the curve, and the left curve section CB in the left-hand traffic zone shown in Fig. 2(b) may be referred to as an inside curve section where the left lane Cl in which vehicle 1 is traveling is on the inside of the curve. Note that in the right-hand traffic zone, the right curve section corresponds to an inside curve section where the lane in which vehicle 1 is traveling is on the inside of the curve, and the left curve section corresponds to an outside curve section where the lane in which vehicle 1 is traveling is on the outside of the curve. Information such as the position (location) of the curve section, curvature, curve start position C1, and curve end position C2 is stored in the map information database 24 as road information.

[0038] A curved road includes a left driving lane Cl and a right driving lane Cr. In left-hand traffic, the left driving lane Cl is the driving lane in which vehicle 1 drives, and the right driving lane Cr is the oncoming lane in which oncoming vehicle 2 drives in the opposite direction to the traveling direction of vehicle 1. In a right curve section CA shown in FIG. 2(a), vehicle 1 drives in the lane Cl on the outside of the curve and passes oncoming vehicle 2 driving in the oncoming lane Cr on the inside of the curve. In a left curve section CB shown in FIG. 2(b), vehicle 1 drives in the lane Cl on the inside of the curve and passes oncoming vehicle 2 driving in the oncoming lane Cr on the outside of the curve.

[0039] When traveling on a curved section, centrifugal force toward the outside of the road, i.e., lateral acceleration, acts on the vehicle. Therefore, passengers are more likely to feel uneasy while traveling on a curved section than while traveling on a straight road. Furthermore, as shown in Figures 2(a) and 2(b), the driver's sense of uneasiness increases when passing an oncoming vehicle 2 on a curved section. This is thought to be because the centrifugal force acting while traveling on a curved section creates a sensation that the vehicle 1 is approaching the oncoming vehicle 2, or that the oncoming vehicle 2 is approaching the vehicle 1.

[0040] Therefore, in this embodiment, the speed control of the vehicle 1 is adjusted so as to suppress the sense of anxiety of the passengers when the vehicle 1 travels through a curved section while traveling autonomously. Specifically, the target speed when the vehicle 1 travels through a curved section while traveling autonomously is set to be smaller than the basic target speed V1 described above. Furthermore, the target speed when traveling through a curved section is made different between when there is an oncoming vehicle 2 passing the vehicle 1 in the curved section and when there is no oncoming vehicle 2. Specifically, the target speed when there is an oncoming vehicle 2 in the curved section is set to be smaller than the target speed when there is no oncoming vehicle 2.

[0041] As described above, the basic target speed V1 is a vehicle speed calculated based on the curvature radius R of the travel route so that the lateral acceleration is equal to or less than the predetermined value G1. For curve sections on the travel route, a target speed V1 at which the lateral acceleration is equal to or less than the predetermined value G1 is also set according to the curvature radius R. The target speed calculation unit 34 calculates the target speed V2 for the curve section, for example, by multiplying the basic target speed V1 by a preset first speed adjustment gain K1. Furthermore, when an oncoming vehicle 2 is traveling in the oncoming lane of the curve section, the target speed V3 for the curve section where the steep slope section D exists is calculated by multiplying the basic target speed V1 by a preset second speed adjustment gain K2.

[0042] That is, it can be expressed as target speed V2=K1×V1 in a curve section where there is no oncoming vehicle 2, and target speed V3=K2×V1 in a curve section where there is an oncoming vehicle 2. Here, appropriate values ​​are set in advance for the first speed adjustment gain K1 and the second speed adjustment gain K2 so as to satisfy the relationship 1>K1>K2. Note that the target speed V3 in a curve section where there is an oncoming vehicle 2 may be calculated by multiplying the target speed V2 in a curve section where there is no oncoming vehicle 2 by a preset speed adjustment gain. The target speeds V1, V2, and V3 in curve sections with the same curvature satisfy the relationship V1>V2>V3.

[0043] Alternatively, the target speed calculation unit 34 may calculate the target speed of the curve section so that the lateral acceleration when the vehicle 1 travels through the curve section by automatic driving is smaller than the predetermined value G1 of the lateral acceleration when calculating the basic target speed V1 described above. For example, the target speed calculation unit 34 sets the limit values ​​G2, G3 of the lateral acceleration smaller than the predetermined value G1 of the lateral acceleration for calculating the basic target speed V1. When the vehicle 1 travels through a curve section where there is no oncoming vehicle 2, the target speed calculation unit 34 calculates the target speed V2 so that the lateral acceleration of the vehicle 1 is equal to or smaller than a first limit value G2 smaller than the predetermined value G1, and when the vehicle 1 travels through a curve section where there is an oncoming vehicle 2, the target speed calculation unit 34 calculates the target speed V3 so that the lateral acceleration of the vehicle 1 is equal to or smaller than a second limit value G3 smaller than the first limit value G2. Here, the first limit value G2 and the second limit value G3 are set to appropriate values ​​in advance so as to satisfy the relationship G1>G2>G3. As a result, the target speeds V1, V2, and V3 in curve sections with the same curvature satisfy the relationship V1>V2>V3.

[0044] In this embodiment, the deceleration start position when entering a curve section where an oncoming vehicle 2 is present is different from the deceleration start position when entering a curve section where an oncoming vehicle 2 is not present. The basic deceleration start position for decelerating to the target speed for the curve section is set to a point C3 a predetermined distance L1 before the curve start position C1 of the curve section, as shown in Figs. 2(a) and (b), for example. For curves with the same curvature, the target speed V3 for the curve section where an oncoming vehicle 2 is present is smaller than the target speed V2 for the curve section where an oncoming vehicle 2 is not present. Therefore, when deceleration is started from the deceleration start position C3, the deceleration until the curve start position C1 of the curve section where an oncoming vehicle 2 is present is larger than the deceleration until the curve start position C1 of the curve section where an oncoming vehicle 2 is present is reached, resulting in sudden braking.

[0045] Therefore, in this embodiment, the deceleration start position when entering a curve section where passing with the oncoming vehicle 2 is predicted is changed to a point C4 before the point C3. The distance L2 from the curve start position C1 to the deceleration start position C4 in the curve section where the oncoming vehicle 2 is present is longer than the distance L1 from the curve start position C1 to the deceleration start position C3 in the curve section where the oncoming vehicle 2 is not present. This makes it possible to make the deceleration when entering a curve section where passing with the oncoming vehicle 2 is predicted almost the same as the deceleration when entering a curve section with the same curvature and where there is no passing with the oncoming vehicle 2. In other words, the distance L2 from the curve start position C1 to the deceleration start position C4 in the curve section where the oncoming vehicle 2 is present is set to a distance that allows deceleration to the target speed V3 at a deceleration that is almost the same as the deceleration required to decelerate to the target speed V2 from the deceleration start position C3 to the curve start position C1 in the curve section where the oncoming vehicle 2 is not present.

[0046] The flow of speed control by the cruise control device 10 of the vehicle 1 in this embodiment will be described in detail below with reference to the flowchart in Fig. 3. When an instruction to start autonomous driving of the vehicle 1 is given by operating a switch (not shown) or the like, the autonomous driving controller 30 starts the speed control process shown in Fig. 3. The speed control process shown in Fig. 3 is repeatedly executed at a predetermined cycle.

[0047] First, in step S101, the environmental state acquisition unit 31 acquires information about the surrounding environment of the vehicle 1 and information about the vehicle state from the external sensor 21 and the internal sensor 22. In addition, the environmental state acquisition unit 31 acquires position information of the vehicle 1 from the positioning device 23, and acquires map information from the map information database 24.

[0048] In step S102, the route generation unit 32 generates a driving route for the vehicle 1 to drive autonomously from the vehicle position of the vehicle 1 to the destination, based on the information acquired in step S101.

[0049] In step S103, the target speed calculation unit 34 calculates a target speed V1 for the vehicle 1 to travel in an autonomous driving manner along the travel route generated in step S102. The target speed V1 is a vehicle speed calculated based on the curvature radius R of the travel route acquired from the road information in the map information database 24 so that the lateral acceleration is equal to or less than a predetermined value G1, and is a basic target speed that serves as a reference in autonomous driving.

[0050] In step S104, the curve detection unit 33 detects whether or not a curve section exists on the driving route generated in step S102, for example, based on road information acquired from the map information database 24. The curve detection unit 33 also acquires information on the location, curvature, start position C1, and end position C2 of the curve section. If the curve detection unit 33 detects a curve section existing on the driving route, the process proceeds to step S105, and if no curve section is detected, the process proceeds to step S109.

[0051] In step S105, the oncoming vehicle detection unit 36 ​​detects whether an oncoming vehicle exists in the curve section based on external data such as image data and point cloud data input from the external sensor 21, or based on oncoming vehicle information acquired from the V2X unit 25. Specifically, as shown in FIG. 2(a) or FIG. 2(b), it detects whether an oncoming vehicle 2 that passes the vehicle 1 in the curve section exists in the oncoming lane Cr. If an oncoming vehicle 2 does not exist in the curve section, the process proceeds to step S106, and if an oncoming vehicle 2 exists in the oncoming lane Cr in the curve section as shown in FIG. 2(a) or FIG. 2(b), the process proceeds to step S107.

[0052] In step S106, the target speed calculation unit 34 calculates a target speed V2 for a curve section where there is no oncoming vehicle 2. On the other hand, in step S107, the target speed calculation unit 34 calculates a target speed V3 for a curve section where there is an oncoming vehicle 2. The target speed V2 for a curve section where there is no oncoming vehicle 2 and the target speed V3 for a curve section where there is an oncoming vehicle 2 are smaller than the basic target speed V1, and the target speed V3 for a curve section where there is no oncoming vehicle 2 is smaller than the target speed V2 for a curve section where there is no oncoming vehicle 2. Therefore, when the curvature of the curve section is the same, the basic target speed V1, the target speed V2 for a curve section where there is no oncoming vehicle 2, and the target speed V3 for a curve section where there is an oncoming vehicle 2 satisfy the relationship V1>V2>V3.

[0053] In step S108, the vehicle control unit 35 changes the deceleration start position when entering the curve section where the oncoming vehicle 2 is present to a point C4 earlier than the point C3. As a result, the distance L2 from the curve start position C1 to the deceleration start position C4 in the curve section where the oncoming vehicle 2 is present becomes longer than the distance L1 from the curve start position C1 to the deceleration start position C3 in the curve section where the oncoming vehicle 2 is not present.

[0054] In step S109, the vehicle control unit 35 sends a drive command to the driving module 50 so as to start deceleration from the deceleration start position C3 or C4 and drive along the driving route at the calculated target speed V1, V2 or V3, thereby performing driving control of the vehicle 1.

[0055] The cruise control device 10 for the vehicle 1 according to the first embodiment described above can achieve the following advantageous effects.

[0056] (1) The driving control device 10 of the vehicle 1 capable of performing autonomous driving includes an environmental state acquisition unit 31 that acquires information on the vehicle state and the surrounding environment of the vehicle 1, a route generation unit 32 that generates a driving route during autonomous driving based on the information acquired by the environmental state acquisition unit 31, a curve detection unit 33 that detects a curve section existing on the driving route based on the information acquired by the environmental state acquisition unit 31, an oncoming vehicle detection unit 36 ​​that detects whether an oncoming vehicle 2 exists in an oncoming lane Cr in the curve section, a target speed calculation unit 34 that calculates a target speed when the vehicle 1 travels autonomously according to the driving route generated by the route generation unit 32, and a vehicle control unit 35 that controls the speed of the vehicle 1 so that the vehicle travels along the driving route at the target speed. The target speed calculation unit 34 sets a first vehicle speed V1 as a target speed so that the lateral acceleration of the vehicle 1 is equal to or less than a predetermined value G1 when the vehicle 1 travels autonomously according to the driving route. When a curve section exists on the driving route, the target speed calculation unit 34 sets the target speed in the curve section to a second vehicle speed V2 that is smaller than the first vehicle speed V1. When an oncoming vehicle 2 is present in a curve section, the target speed calculation unit 34 sets the target speed in the curve section where the oncoming vehicle 2 is present to a third vehicle speed V3 that is lower than the second vehicle speed V2.

[0057] When the vehicle 1 travels through a curved section, the passenger may feel uneasy as if the vehicle 1 is being pushed outward by centrifugal force, or as if the outer side of the road is approaching the vehicle 1. This feeling of uneasiness increases when the vehicle passes an oncoming vehicle 2 in a curved section. Therefore, by setting the target speeds V2 and V3 when the vehicle 1 travels through a curved section by automatic driving to be smaller than the basic target speed V1, the passenger's sense of uneasiness during automatic driving can be suppressed. Furthermore, by setting the target speed V3 in a curved section where the oncoming vehicle 2 is present to be smaller than the target speed V2 in a curved section where the oncoming vehicle 2 is not present, it is possible to reliably suppress the passenger's sense of uneasiness when passing the oncoming vehicle 2 in a curved section. The target speed V2 in a curved section where the oncoming vehicle 2 is not present is set to be smaller than the basic target speed V1 but larger than the target speed V3 in a curved section where the oncoming vehicle 2 is present, so that the passenger can be prevented from feeling uncomfortable due to the vehicle speed being too slow in a curved section where there is no sense of uneasiness, such as contact with the oncoming vehicle 2.

[0058] (2) The vehicle control unit 34 is configured to start deceleration control for decelerating to a target speed in the curve section from a deceleration start position C3 set before the curve start position C1 in the curve section. The vehicle control unit 34 sets the deceleration start position C4 when entering the outside curve section CA so that a distance L2 from the curve start position C1 to the deceleration start position C4 in the curve section where an oncoming vehicle 2 is present is longer than a distance L1 from the curve start position C1 to the deceleration start position C3 in the curve section where an oncoming vehicle 2 is not present.

[0059] When the curvature of the curve section is the same, the target speed V3 in the curve section where the oncoming vehicle 2 is present is smaller than the target speed V2 in the curve section where the oncoming vehicle 2 is not present, so if deceleration starts from the same deceleration start position C3, sudden braking will occur in the curve section where the oncoming vehicle 2 is present, which may cause passengers to feel uneasy. By changing the deceleration start position C3 to point C4 in the curve section where the oncoming vehicle 2 is present, the deceleration when entering a curve section where the oncoming vehicle 2 is present and the deceleration when entering a curve section where the oncoming vehicle 2 is not present can be made approximately the same.

[0060] (3) The target speed calculation unit 34 calculates the target speed V2 by multiplying the target speed V1 by a first speed adjustment gain (first coefficient) K1, and calculates the target speed V3 by multiplying the target speed V1 by a second speed adjustment gain (second coefficient) K2 that is smaller than the first speed adjustment gain K1. By appropriately adjusting the coefficients K1 and K2, it is possible to appropriately calculate the target speed V2 in a curve section where there is no oncoming vehicle 2 and the target speed V3 in a curve section where there is an oncoming vehicle 2, based on the basic target speed V1.

[0061] (4) Alternatively, the target speed calculation unit 34 may calculate the target speed V2 in accordance with the curvature of the curve section so that the lateral acceleration of the vehicle 1 is equal to or less than a first limit value G2 smaller than a predetermined value G1 when the vehicle 1 travels through a curve section where there is no oncoming vehicle 2, and may calculate the target speed V3 in accordance with the curvature of the curve section so that the lateral acceleration of the vehicle 1 is equal to or less than a second limit value G3 smaller than the first limit value G2 when the vehicle 1 travels through a curve section where there is an oncoming vehicle 2. This makes it possible to appropriately calculate the target speed V2 in the curve section where there is no oncoming vehicle 2 and the target speed V3 in the curve section where there is an oncoming vehicle 2 from the viewpoint of the lateral acceleration acting on the vehicle 1 when traveling through the curve section.

[0062] -Second embodiment- A vehicle cruise control device according to a second embodiment of the present invention will be described below. The basic configuration of the vehicle cruise control device according to the second embodiment is similar to that of the first embodiment described above. The following mainly describes the differences from the first embodiment.

[0063] As described in the first embodiment, when traveling through a curved section, centrifugal force toward the outside of the road, i.e., lateral acceleration, acts on the vehicle. Therefore, when traveling through a left curved section CB during automatic driving, the passenger may feel uneasy as if the vehicle 1 is pushed toward the oncoming lane Cr on the outside of the curve by centrifugal force, or that the oncoming lane Cr is approaching the vehicle 1. In this case, if an oncoming vehicle 2 is present on the outside of the curve in the left curved section CB, the passenger feels even more uneasy. This is considered to be because the lateral acceleration acting on the vehicle 1 creates a sensation that the oncoming vehicle 2 traveling on the outside of the curve is approaching (approaching) the vehicle 1. When an oncoming vehicle 2 is present in the oncoming lane Cr on the outside of the curve in the left curved section CB, the passenger feels more uneasy than when an oncoming vehicle 2 is present in the oncoming lane Cr on the inside of the curve in the right curved section CA.

[0064] Therefore, in this embodiment, the target speed when traveling through a curve section where an oncoming vehicle 2 exists is made different between a case where passing an oncoming vehicle 2 traveling in the oncoming lane Cr on the outside of the curve in a left curve section CB is predicted and a case where passing an oncoming vehicle 2 traveling in the oncoming lane Cr on the inside of the curve in a right curve section CA is predicted. Specifically, the target speed when the oncoming vehicle 2 exists in the oncoming lane Cr on the outside of the curve in a left curve section CB is set to be smaller than the target speed when the oncoming vehicle 2 exists in the oncoming lane Cr on the inside of the curve in a right curve section CA.

[0065] When the oncoming vehicle detection unit 36 ​​predicts that the vehicle will pass the oncoming vehicle 2 traveling in the oncoming lane Cr on the outside of the curve in the left curve section CB on the travel route, the target speed calculation unit 34 sets the target speed in the left curve section CB where the oncoming vehicle 2 exists to a target speed V4 that is smaller than the target speed V3. The target speed calculation unit 34 calculates the target speed V4 in the left curve section CB where the oncoming vehicle 2 exists, for example, by multiplying the target speed V3 in the curve section where the oncoming vehicle 2 exists by a third speed adjustment gain K3 set in advance. That is, the target speed V4 in the left curve section CB where the oncoming vehicle 2 exists can be expressed as V4=K3×V3. Here, the third speed adjustment gain K3 is set to an appropriate value in advance so as to satisfy the relationship 1>K3. The target speeds V3 and V4 in the curve sections with the same curvature satisfy the relationship V3>V4. For the right curve section CA where the oncoming vehicle 2 exists, the target speed V3 in the curve section where the oncoming vehicle 2 exists is adopted.

[0066] The flow of speed control by the cruise control device 10 of the vehicle 1 in this embodiment will be described in detail below with reference to the flowchart of Fig. 4. When an instruction to start autonomous driving of the vehicle 1 is given by operating a switch (not shown) or the like, the autonomous driving controller 30 starts the speed control process shown in Fig. 4. The processes in steps S101 to S106 shown in Fig. 4 are similar to the processes in steps S101 to S106 in the flowchart of Fig. 3, and therefore will not be described.

[0067] If it is determined in step S105 that an oncoming vehicle 2 is present in the curve section, the process proceeds to step S111. In step S111, it is determined whether the detected oncoming vehicle 2 is present in the oncoming lane Cr on the outside of the curve in an inside curve section (left curve section) CB, or in the oncoming lane Cr on the inside of the curve in an outside curve section (right curve section) CA. If the curve section is an outside curve section where the lane of the vehicle 1 is on the outside of the curve, that is, a right curve section CA in left-hand traffic, and the oncoming vehicle 2 is traveling in the oncoming lane Cr on the inside of the curve, the process proceeds to step S112. On the other hand, if the curve section is an inside curve section where the lane of the vehicle 1 is on the inside of the curve, that is, a left curve section CB in left-hand traffic, and the oncoming vehicle 2 is traveling in the oncoming lane Cr on the outside of the curve, the process proceeds to step S113.

[0068] In step S112, the target speed calculation unit 34 calculates a target speed V3 for the right curve section CA where the oncoming vehicle 2 is present. This target speed V3 is the same as the target speed V3 for the curve section where the oncoming vehicle 2 is present described above. In step S113, a target speed V4 for the left curve section CB where the oncoming vehicle 2 is present is calculated. The target speed V4 for the left curve section CB where the oncoming vehicle 2 is present is set to be smaller than the target speed V3 for the right curve section CA where the oncoming vehicle 2 is present and has the same curvature.

[0069] In step S108, the vehicle control unit 35 changes the deceleration start position when entering a curve section where the oncoming vehicle 2 is present to a point C4 before the point C3. As a result, the distance L2 from the curve start position C1 to the deceleration start position C4 in the curve section where the oncoming vehicle 2 is present becomes longer than the distance L1 from the curve start position C1 to the deceleration start position C3 in the curve section where the oncoming vehicle 2 is not present. Note that, in order to decelerate to the target speed V3 or the target speed V4 with the same deceleration, the distance from the deceleration start position C4 to the curve start position C1 when entering a left curve section CB where the oncoming vehicle 2 is present may be set longer than the distance from the deceleration start position C4 to the curve start position C1 when entering a right curve section CA where the oncoming vehicle 2 is present.

[0070] In step S109, the vehicle control unit 35 sends a drive command to the driving module 50 so as to start deceleration from the deceleration start position C3 or C4 and drive along the driving route at the calculated target speed V1, V2, V3, or V4, thereby performing driving control of the vehicle 1.

[0071] In the cruise control device 10 for the vehicle 1 according to the second embodiment described above, in addition to the effects of the first embodiment described above, the following operational effects can be achieved.

[0072] (1) When the curve detection unit 33 detects an inner curve section CB on the driving route where the vehicle 1's driving lane Cl is on the inside of the curve and the oncoming lane Cr is on the outside of the curve, and the oncoming vehicle detection unit 36 ​​detects an oncoming vehicle 2 in the oncoming lane Cr in the inner curve section CB, the target speed calculation unit 34 sets the target speed to a fourth vehicle speed V4 which is smaller than the third vehicle speed V3.

[0073] In an inner curve section (left curve section) CB where the vehicle 1 is traveling in the lane on the inside of the curve, the passenger feels as if the vehicle 1 is being pushed toward the oncoming lane Cr on the outside of the curve by centrifugal force, or as if the oncoming lane Cr is approaching the vehicle 1, causing anxiety. When an oncoming vehicle 2 is present in the oncoming lane Cr on the outside of the curve in the inner curve section CB, the passenger feels as if the vehicle 1 is approaching the oncoming vehicle 2 by centrifugal force, and is more likely to feel anxious than when the oncoming vehicle 2 is present on the inside of the curve in the outer curve section CA. Therefore, the target speed when the oncoming vehicle 2 is present on the inside of the curve in the outer curve section (right curve section) CA is set to V3, and the target speed when the oncoming vehicle 2 is present on the outside of the curve in the inner curve section (left curve section) CB is set to V4, which is smaller than V3. This makes it possible to suppress the passenger's sense of anxiety in the inner curve section CB where the oncoming vehicle 2 is present on the outside of the curve.

[0074] -Third embodiment- A vehicle cruise control device according to a third embodiment of the present invention will be described below. The basic configuration of the vehicle cruise control device according to the fourth embodiment is similar to that of the first and second embodiments described above. The following mainly describes the differences from the first embodiment.

[0075] In the above-described embodiment, the target speed is adjusted to suppress the anxiety felt by the passengers when the vehicle 1 passes the oncoming vehicle 2 while traveling through a curved section in an autonomous driving mode, but this anxiety is considered to be more pronounced when the vehicle 1 and the oncoming vehicle 2 are traveling in adjacent lanes. Therefore, in this embodiment, on roads having multiple lanes traveling in the same direction, such as roads with two or more lanes on each side, the above-described adjustment of the target speed and deceleration start position is performed only when the traveling lane on which the vehicle 1 is traveling and the oncoming lane on which the oncoming vehicle 2 is traveling are adjacent to each other.

[0076] The environmental state acquisition unit 31 can determine whether the vehicle 1 is traveling in the innermost lane of the outer curve section CA or the outermost lane of the inner curve section CB based on external data such as image data and point cloud data input from the external sensor 21. In other words, it can determine whether the vehicle 1 is traveling in the lane closest to the oncoming traffic in the curve section.

[0077] Further, the oncoming vehicle detection unit 36 ​​can determine whether the oncoming vehicle 2 is traveling in the outermost lane of the curve in the outer curve section CA or the innermost lane of the curve in the inner curve section CB based on external data such as image data and point cloud data input from the external sensor 21, or based on oncoming vehicle information acquired from the V2X unit 25. That is, it can determine whether the oncoming vehicle 2 is traveling in the lane closest to the driving lane of the vehicle 1 in the curve section. Note that even in the case of a curve section in which the driving lane and the oncoming lane each have only one lane, it can be determined that the vehicle 1 and the oncoming vehicle 2 are traveling in adjacent lanes.

[0078] When it is determined that the vehicle 1 and the oncoming vehicle 2 are traveling in adjacent lanes in the curve section, the target speed calculation unit 34 calculates a target speed V3 for the curve section in which the oncoming vehicle 2 exists, and the vehicle control unit 35 changes the deceleration start position when entering the curve section in which the oncoming vehicle 2 is expected to pass each other to a point C4 before the point C3. When it is determined that the vehicle 1 and the oncoming vehicle 2 are traveling in non-adjacent lanes in the curve section, the target speed calculation unit 34 can set, for example, the target speed V2 for the curve section in which the oncoming vehicle 2 does not exist as the target speed when the traveling lane of the vehicle 1 and the oncoming lane of the oncoming vehicle 2 are not adjacent in the curve section. Specifically, when it is determined in step S105 of the flowchart in FIG. 3 described above that the oncoming vehicle 2 exists in the oncoming lane adjacent to the traveling lane of the vehicle 1 in the curve section, the process proceeds to step S107. On the other hand, if it is determined that the lane of the vehicle 1 and the lane of the oncoming vehicle 2 are not adjacent to each other in the curve section, or that the oncoming vehicle 2 is not present in the curve section, the process proceeds to step S106.

[0079] The cruise control device for the vehicle 1 according to the third embodiment described above can achieve the following advantageous effects in addition to the advantageous effects achieved by the first and second embodiments described above.

[0080] When a curved section on the travel route has a plurality of lanes, the target speed calculation unit 34 sets the target speed to the third vehicle speed V3, and the vehicle speed control unit 35 changes the deceleration start position only when the travel lane Cl of the vehicle 1 is adjacent to the oncoming lane Cr where the oncoming vehicle 2 is present. When the curved section is a road with two or more lanes on each side, when the vehicle 1 and the oncoming vehicle 2 are traveling on adjacent lanes, a strong sense of anxiety about approaching the oncoming vehicle 2 occurs. Therefore, the sense of anxiety can be suppressed by limiting the change of the target speed and the deceleration start position to the case where the travel lane Cr of the vehicle 1 is adjacent to the oncoming lane Cl of the oncoming vehicle 2. In addition, when the vehicle 1 and the oncoming vehicle 2 are not traveling on adjacent lanes and the sense of anxiety about approaching the oncoming vehicle 2 is considered to be small, the target speed and the deceleration start position are not changed, so that it is possible to suppress the discomfort felt by the occupants due to the vehicle speed in the curved section being too slow, and to minimize the effect on the total travel time of the vehicle 1 to the destination.

[0081] -Variations- (1) In the first embodiment described above, the target speed is adjusted when the vehicle 1 is predicted to pass the oncoming vehicle 2 while traveling through a curved section in an autonomous driving mode, but the target speed during autonomous driving may be adjusted in consideration of the gradient of the road. For example, when the curved section is downhill, it is considered that the passenger's anxiety increases as the vehicle 1 may run into the oncoming lane on the outside of the curve and come into contact with the oncoming vehicle 2, or the oncoming vehicle 2 may approach the vehicle 1 from the oncoming lane on the inside of the curve. Therefore, in this embodiment, the target speed is set to be smaller on roads with a downward gradient of a predetermined percentage or more than flat roads.

[0082] The curve section detection unit 33 can detect, based on road information acquired from the map information database 24, for example, whether or not a curve section exists on a downward slope.

[0083] The target speed calculation unit 34 sets the above-mentioned target speed V3, for example, when the curve section where the oncoming vehicle 2 is present is a flat road, and sets the target speed to a target speed V5 which is smaller than the target speed V3, when the curve section where the oncoming vehicle 2 is present is a downward slope.

[0084] The target speed calculation unit 34 calculates a target speed V5 in a downwardly sloping curve section where the oncoming vehicle 2 is present, for example, by multiplying the target speed V3 in the curve section where the oncoming vehicle 2 is present by a preset fourth speed adjustment gain K4. That is, the target speed V5 in the downwardly sloping curve section where the oncoming vehicle 2 is present can be expressed as: target speed V5=K4×V3. Here, the fourth speed adjustment gain K4 is set to an appropriate value in advance so as to satisfy the relationship 1>K4. The target speeds V3 and V5 in curve sections with the same curvature satisfy the relationship V3>V5.

[0085] In the second embodiment described above, the target speed during autonomous driving may be adjusted taking into account the gradient of the road. For example, when the left curve section CB where the oncoming vehicle 2 is present is a downward gradient, the target speed can be set to be smaller than when the left curve section CB where the oncoming vehicle 2 is present is a flat road.

[0086] (2) In the above-described embodiment, when passing an oncoming vehicle 2 in a curve section is predicted, the target speed for the curve section is set to a smaller value than when passing an oncoming vehicle 2 is not predicted. The vehicle control unit 35 can control the traveling module 50 to travel through the curve section while maintaining the set target speed from the curve start position C1 to the curve end position C2.

[0087] Alternatively, the vehicle control unit 35 may control the traveling module 50 to accelerate the vehicle 1 after the vehicle 1 has passed the oncoming vehicle 2. For example, when the vehicle control unit 35 enters a curved section where the vehicle 1 is expected to pass the oncoming vehicle 2, the vehicle control unit 35 can control the traveling module 50 to decelerate the vehicle speed of the vehicle 1 to a target speed V3, pass the oncoming vehicle 2 at the target speed V3, and when the vehicle 1 has passed the oncoming vehicle 2, accelerate the vehicle speed of the vehicle 1 to the target speed V2 and travel to the end position C2 of the curved section at the target speed V2. In this way, by quickly accelerating the target speed from V3 to V2 after the vehicle 1 has passed the oncoming vehicle 2, the passenger's sense of anxiety is suppressed, and the passenger does not feel uncomfortable due to the vehicle speed being too slow in the curved section. In addition, the effect on the total travel time of the vehicle 1 to the destination can be minimized.

[0088] (3) In the above-described embodiment, the deceleration start position when entering a curve section where an oncoming vehicle 2 is present is changed to point C4 before point C3 that is a predetermined distance L1 away from curve start point C1. However, this is not limited to this, and the deceleration start position may be fixed to point C3 that is a predetermined distance L1 away from curve start point C1, and the deceleration start position may not be changed. Also, instead of changing the deceleration start position when entering a curve section where an oncoming vehicle 2 is present, a configuration may be used in which the vehicle decelerates at a constant deceleration rate when entering a curve section, regardless of whether or not there is an oncoming vehicle 2.

[0089] (4) In the above-described embodiment, the target speeds V2, V3 for the curve section where there is no oncoming vehicle 2 and the curve section where there is an oncoming vehicle 2 are calculated using the first and second speed adjustment gains K1, K2 or the first and second limit values ​​G2, G3 of the lateral acceleration based on the target speed V1 where the lateral acceleration is equal to or less than a predetermined value G1. However, this is not limited to this, and the target speeds V2, V3 may be determined from speed maps for the curve section where there is no oncoming vehicle 2 and the curve section where there is an oncoming vehicle 2, which are prepared in advance for each curvature.

[0090] (5) In the above-described embodiment, the curve detection unit 33 detects whether or not a curve section exists on the driving route based on information on the road shape input from the map information database 24, but this is not limited to the above. For example, the curve detection unit 33 may be configured to detect a curve section existing on the driving route based on external data such as image data and point cloud data input from the external sensor 21. However, as described above, by detecting a curve section before the start of autonomous driving based on high-precision three-dimensional map information acquired from the map information database 24, the load due to control processing during autonomous driving can be reduced.

[0091] Alternatively, the curve detection unit 33 may be configured to detect, as a curve section, a section in which lateral acceleration exceeding a preset value occurs when the vehicle 1 travels at a speed set by the user that is equal to or lower than the speed limit of the road. The lateral acceleration of the vehicle 1 when traveling along a travel route can be calculated based on, for example, the curvature of the road acquired by the environmental state acquisition unit 31, a target steering angle for autonomous driving, and the like. By detecting the curve section before the start of autonomous driving, the load due to the control processing during autonomous driving can be suppressed.

[0092] (6) In the above-described embodiment, the basic target speed V1, the target speed V2 for the curve section where there is no oncoming vehicle 2, and the target speed V3 for the curve section where there is an oncoming vehicle 2 are set to satisfy the relationship V1>V2>V3. However, this is not limited to this, and the basic target speed V1 may be used as it is as the target speed V2 for the curve section where there is no oncoming vehicle 2.

[0093] Although several embodiments of the present invention have been described above, it should be noted that the present invention is not limited to the above-described embodiments, and various modifications and variations are possible within the scope of the present invention. [Explanation of symbols]

[0094] 1 vehicle 2 Oncoming vehicles 10 Driving control device 24 Map information database 30 Autonomous Driving Controller 31 Environmental status acquisition unit 32 Route Generation Unit 33 Curve detection section 34 Target speed calculation section 35 Vehicle control unit 36 Oncoming vehicle detection unit C1 Curve start position C3,C4 Deceleration start position G1 Predetermined value of lateral acceleration G2,G3 1st and 2nd limit values K1~K4 1st to 4th speed adjustment gain

Claims

1. A vehicle driving control device capable of performing autonomous driving, an environmental state acquisition unit that acquires information regarding a vehicle state and a surrounding environment of the vehicle; A route generation unit that generates a driving route during autonomous driving based on the information acquired by the environmental state acquisition unit; a curve detection unit that detects a curve section present on the travel route based on the information acquired by the environmental state acquisition unit; an oncoming vehicle detection unit that detects whether an oncoming vehicle is present in an oncoming lane in the curve section; a target speed calculation unit that calculates a target speed when the vehicle travels autonomously along the travel route generated by the route generation unit; a vehicle control unit that controls a speed of the vehicle so that the vehicle travels along the travel route at the target speed; Equipped with the target speed calculation unit sets a first vehicle speed as the target speed such that a lateral acceleration of the vehicle is equal to or less than a predetermined value when the vehicle is autonomously driven along the travel route; the target speed calculation unit, when a curve section is present in the travel route, sets the target speed in the curve section to a second vehicle speed that is lower than the first vehicle speed; The target speed calculation unit, when an oncoming vehicle is present in the curve section, sets the target speed in the curve section where the oncoming vehicle is present to a third vehicle speed which is lower than the second vehicle speed.

2. 2. The vehicle driving control device according to claim 1, wherein when the curve detection unit detects an inner curve section on the driving route in which the vehicle's driving lane is on the inside of the curve and the oncoming lane is on the outside of the curve, and when the oncoming vehicle detection unit detects the oncoming vehicle in the oncoming lane of the inner curve section, the target speed calculation unit sets the target speed to a fourth vehicle speed that is lower than the third vehicle speed.

3. the vehicle control unit is configured to start deceleration control for decelerating the vehicle to the target speed in the curve section from a deceleration start position that is set before a start position of the curve section, 3. The vehicle driving control device of claim 1, wherein the vehicle control unit changes the deceleration start position when entering the curve section so that the distance from the start position of the curve section where the oncoming vehicle is present to the deceleration start position is longer than the distance from the start position of the curve section where the oncoming vehicle is not present to the deceleration start position.

4. 4. The vehicle driving control device according to claim 3, wherein, when the curve section on the driving route has a plurality of lanes, the target speed calculation unit sets the target speed to the third vehicle speed only when the lane on which the vehicle is traveling is adjacent to the oncoming lane on which the oncoming vehicle is present.

5. The target speed calculation unit Calculating the second vehicle speed by multiplying the first vehicle speed by a first coefficient; The vehicle cruise control device according to claim 1 , wherein the third vehicle speed is calculated by multiplying the first vehicle speed by a second coefficient that is smaller than the first coefficient.

6. The target speed calculation unit calculating the second vehicle speed in accordance with a curvature of the curve section such that a lateral acceleration of the vehicle is equal to or less than a first limit value that is smaller than the predetermined value when the vehicle travels through the curve section; 2. The vehicle driving control device according to claim 1, wherein when the vehicle is traveling through the curve section in which the oncoming vehicle is present, the third vehicle speed is calculated in accordance with a curvature of the curve section so that the lateral acceleration of the vehicle is equal to or less than a second limit value that is smaller than the first limit value.

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