JP2011207242A - Vehicle travel control system - Google Patents

Abstract

A vehicle travel control system capable of controlling the travel state of a vehicle in accordance with a driver's sense on a road having a plurality of curved sections.
SOLUTION: A traveling state changing unit that changes a traveling state of a vehicle and a control device that controls the traveling state changing unit according to a corner. The control unit considers a straight road and a straight road The vehicle's behavior while traveling on a forward road having two curved sections connected by the vehicle while traveling on a section regarded as a straight road from one of the two curved sections to the other, based on the driving history of the driver Is predicted to be stable (S5-Y), the traveling state changing means is controlled with the two curved sections as independent corners (S6 to S9), and the vehicle travels in the section regarded as a straight road based on the traveling history. When the behavior of the vehicle is not predicted to be stable in the meantime (S5-N), the traveling state changing means is controlled with one corner as the two curved sections and the section regarded as a straight road (S10, S11).
[Selection] Figure 1

Description

  The present invention relates to a vehicle travel control system.

  2. Description of the Related Art Conventionally, techniques for performing vehicle travel control according to a corner have been proposed. For example, in Patent Document 1, when there is a curve ahead, a curve with the minimum curvature is detected, a limit vehicle speed that is an appropriate approach speed to this curve is obtained, and the vehicle speed during traveling is greater than or equal to the limit vehicle speed The technology of the driving support device that performs deceleration control is disclosed.

Japanese Patent Laid-Open No. 10-19595

  However, there is still room for study on making the vehicle travel control in accordance with the driver's sense on the road where a plurality of curved sections continue. For example, the driving control along the driver's feeling may differ depending on the driver's skill and line taking.

  An object of the present invention is to provide a vehicle traveling control system capable of controlling the traveling state of a vehicle along a driver's sense on a traveling road having a plurality of curved sections.

  A vehicle travel control system according to the present invention includes a travel state change unit that changes a travel state of a vehicle, and a control device that controls the travel state change unit according to a corner, and the control device is a section regarded as a straight road. And on the front road having two curved sections connected by the section regarded as the straight road, the straight road from one of the two curved sections to the other based on the driving history by the driver When the behavior of the vehicle is predicted to be stable while traveling in the considered section, the traveling state changing means is controlled using the two curved sections as the corners independent of each other, and the straight road is based on the traveling history. If the behavior of the vehicle is not predicted to be stable while traveling in the section regarded as a straight section, the two curved sections and the section regarded as the straight road are regarded as one corner. And controlling the running state change means.

  In the vehicle travel control system, the travel state changed by the travel state changing means is a vehicle speed of the vehicle, and the control device performs vehicle speed control based on a target vehicle speed according to the corner. When the behavior of the vehicle is predicted to be stable while traveling on the section regarded as the straight road, the target vehicle speed is set for each of the two curved sections, and the vehicle speed control is performed by the traveling state changing means. If the behavior of the vehicle is not expected to be stable while traveling in the section regarded as the straight road, one target vehicle speed is set for the whole of the two curved sections and the section regarded as the straight road. It is preferable to perform vehicle speed control by the travel state changing means.

  In the vehicle travel control system, the section regarded as the straight road is preferably a section whose curvature is equal to or less than a predetermined value.

  The vehicle travel control system preferably includes at least one of a braking force changing means for changing a braking force, an automatic transmission, an active suspension, and an acceleration changing means for changing an acceleration as the traveling state changing means.

  The vehicle travel control system of the present invention includes travel state change means for changing the travel state of the vehicle, and a control device for controlling the travel state change means in accordance with a corner. Based on the history, when the past trajectory of the vehicle on the forward road has a region regarded as a straight line and two curved regions connected by the region regarded as the straight line, one of the two curved regions If the behavior of the vehicle is predicted to be stable while traveling in the region regarded as the straight line from the other to the other, the traveling state changing means is controlled with the two curved regions as the corners independent of each other, If the vehicle behavior is not predicted to be stable while traveling in a region regarded as a straight line, the two curved regions and the region regarded as a straight line are regarded as one corner. And controlling the running state change means.

  The vehicle travel control system according to the present invention is based on a case where the behavior of the vehicle is predicted to be stable while traveling in a section regarded as a straight road from one of two curved sections to the other based on a travel history by the driver. Controls the running state changing means with the two curved sections as independent corners. On the other hand, if the behavior of the vehicle is not predicted to be stable while traveling on a section regarded as a straight road based on the travel history, the traveling state changing means is controlled with two curved sections and a section regarded as a straight road as one corner. . As described above, according to the vehicle travel control system of the present invention, the travel history is reflected in the corner recognition, so that the vehicle travel state can be controlled in accordance with the driver's sense. Play.

FIG. 1 is a flowchart showing the operation of the vehicle travel control system of the embodiment. FIG. 2 is a diagram illustrating a vehicle to which the vehicle travel control system of the embodiment is applied. FIG. 3 is a diagram illustrating an example of a plurality of traveling tracks in the composite corner. FIG. 4 is a diagram illustrating an example of a curvature distribution of a past travel locus. FIG. 5 is a diagram illustrating an example of a curvature distribution of a traveling locus in an S-shaped corner.

  Hereinafter, an embodiment of a vehicle travel control system according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

(First embodiment)
The first embodiment will be described with reference to FIGS. 1 to 5. The present embodiment relates to a vehicle travel control system including a control device that controls travel state change means according to a corner. FIG. 1 is a flowchart showing the operation of an embodiment of a vehicle travel control system according to the present invention, and FIG. 2 is a diagram showing a vehicle to which the vehicle travel control system of the embodiment is applied.

  When the vehicle travel control system 1-1 of the present embodiment performs vehicle travel control such as deceleration and cornering control at complicated corners, the vehicle travel control system 1-1 is a single composite corner or two or more corners are continuous. The travel control is performed by distinguishing between the two. Specifically, when the section that can be regarded as a straight line between corners is longer than the distance at which the vehicle behavior is stable, the vehicle is recognized as a plurality of corners, and the driving control for each corner is executed. When the distance is equal to or shorter than the distance, the corners before and after the section are recognized as one composite corner and the traveling control is executed. Whether the corner is recognized as plural or one is determined based on the travel history. Thereby, a corner can be recognized according to a driving style of a driver, and driving control of a vehicle according to a driver's sense is attained.

  As shown in FIG. 2, the vehicle 1 is provided with an engine 11. An automatic transmission 13 having a torque converter 12 is connected to the engine 11. The driving force of the engine 11 is input to the automatic transmission 13 via the torque converter 12 and transmitted to the driving wheels 16 via the differential gear 14 and the drive shaft 15. In the automatic transmission 13, the gear ratio is automatically controlled by the A / T hydraulic control device 17 in accordance with the driving state of the vehicle. The brake device 18 is controlled by the brake hydraulic pressure control device 19 to brake the vehicle. In the present embodiment, the brake device 18 is a braking force changing unit that changes the braking force, and functions as a traveling state changing unit that changes the traveling state of the vehicle 1. The brake device 18 can change the vehicle speed of the vehicle 1 by the braking force.

  The vehicle 1 is provided with an electronic control unit (ECU) 20 that controls the engine 11, the automatic transmission 13, the brake device 18, and the like. The ECU 20 performs comprehensive control of the engine 11, the automatic transmission 13 (A / T hydraulic control device 17), and the brake device 18 (brake hydraulic control device 19). In this embodiment, ECU20 functions as a control apparatus which controls the brake device 18 as a driving state change means according to a corner. The engine 11 can function as an acceleration changing unit that changes the acceleration (driving force) of the vehicle by controlling the output torque by being controlled by the ECU 20.

  The vehicle 1 is provided with an accelerator position sensor 21 for detecting an operation amount (accelerator opening) of an accelerator pedal. A signal indicating the accelerator opening detected by the accelerator position sensor 21 is output to the ECU 20. A throttle control valve 23 provided in the intake pipe 22 of the engine 11 can be opened and closed by a throttle actuator 24. The ECU 20 can control the throttle opening of the throttle control valve 23 by the throttle actuator 24 regardless of the accelerator opening. The vehicle 1 is provided with a throttle opening sensor (not shown) that detects the fully closed state (idle state) of the throttle control valve 23 and the throttle opening. Signals indicating the idle state and the throttle opening detected by the throttle opening sensor are output to the ECU 20.

  The engine 11 is provided with an engine speed sensor 28 that detects the engine speed (engine speed). The vehicle speed sensor 29 detects the vehicle speed of the vehicle. The shift position sensor 30 detects the position (shift position) of the shift lever operated by the driver. The brake operation amount sensor 32 detects the operation amount of the brake device 18. The steering angle sensor 33 detects the steering angle of the steering operated by the driver. Signals indicating detection results of the sensors 28, 29, 30, 32, and 33 are output to the ECU 20.

  The ECU 20 has a shift map, determines the gear position of the automatic transmission 13 based on the throttle opening, vehicle speed, and the like, and sets the A / T hydraulic control device 17 so as to establish the determined gear position. Can be controlled.

  The lateral G sensor 37 detects the lateral G of the vehicle, and the longitudinal G sensor 38 detects the longitudinal G of the vehicle. Each of the signal indicating the lateral G detected by the lateral G sensor 37 and the signal indicating the longitudinal G detected by the longitudinal G sensor 38 are output to the ECU 20.

  The yaw rate sensor 40 detects the yaw rate of the vehicle. A signal indicating the yaw rate detected by the yaw rate sensor 40 is output to the ECU 20.

  The navigation device 50 has a basic function of guiding the host vehicle to a predetermined destination, and includes an ECU 60, an operation unit 51, a display unit 52, a speaker 53, a position detection unit 54, and a map database 55. And an operation history recording unit 56. The ECU 60 of the navigation device 50 is capable of bidirectional communication with the ECU 20.

  The CPU 61 of the ECU 60 performs various arithmetic processes such as a navigation process based on the input information. The ROM 62 of the ECU 60 stores various programs for searching a route to the destination, traveling guidance in the route, determining a specific section, and the like. The RAM 63 is a readable / writable memory.

  The position detection unit 54 includes a GPS receiver, a geomagnetic sensor, a distance sensor, a beacon sensor, and a gyro sensor. The position detection unit 54 detects the position of the host vehicle, and outputs data indicating the detected position of the host vehicle to the ECU 60.

  The map database 55 stores information (map, straight road, curve, uphill / downhill, highway, etc.) necessary for vehicle travel. The map database 55 includes a map data file, an intersection data file, a node data file, and a road data file. The ECU 60 reads out necessary information with reference to the map database 55. The ECU 20 can also determine whether there is a preceding vehicle by using a radar or the like and switch the control of this embodiment on / off.

  The vehicle 1 is provided with an active suspension 31. The active suspension 31 can change suspension characteristics by an actuator, and can control the roll rigidity of the vehicle 1 variably. The vehicle 1 may include another device (for example, an active stabilizer) that can variably control the roll rigidity, instead of the active suspension. The active suspension 31 is connected to the ECU 20 and controlled by the ECU 20. The vehicle travel control system 1-1 of the present embodiment includes an ECU 20 and a brake hydraulic pressure control device 19.

  The ECU 20 can execute travel control (corner control) of the vehicle 1 in accordance with the corner. The ECU 20 of the present embodiment executes deceleration control with brake assistance for the corner in front of the vehicle. The ECU 20 determines a target vehicle speed during cornering based on the curvature of the front corner, and controls the brake device 18 so that the vehicle speed becomes the target vehicle speed at a control target position (for example, before the corner) set for the corner. By controlling and performing vehicle speed control, the driver's braking operation is assisted. In the present embodiment, the ECU 20 performs vehicle speed control based on the target vehicle speed according to the past travel locus on the forward travel path.

  Here, in the past, sufficient studies have not been made to make the driving control along the driving path (composite corner) in which a plurality of curved sections follow the driver's sense. For example, in a composite corner in which a plurality of curve sections are continuous, the running control in which corner control can be performed only on one curve section may not match the driver's feeling. Even if the corner control is performed by recognizing the composite corner, the control may not be in line with the driver's feeling. This is because, as will be described below with reference to FIG. 3, an appropriate control target value may vary depending on the vehicle speed, the skill of the driver (traveling style), and the like.

  FIG. 3 is a diagram illustrating an example of a plurality of traveling tracks in the composite corner. In FIG. 3, the code | symbol C1 shows a composite corner. In the composite corner C1, the first corner (curved section) C11 and the second corner (curved section) C12 are connected by a short straight road (section regarded as a straight road) C13. In the composite corner C1, a driver who takes a line as if traveling on one corner with respect to the first corner C11, the straight road C13 and the second corner C12 as indicated by a broken line L1, and a solid line L2. There is a driver who takes a line as an independent corner for each of the first corner C11 and the second corner C12 like a route. Further, line travel may vary depending on the vehicle speed when traveling through the composite corner C1. In such a composite corner C1, the driver may feel a sense of discomfort if it is not appropriate to determine whether the driving should be recognized as a plurality of corners or whether the driving should be recognized as one corner.

  Further, even if the driver drives the vehicle 1 along the solid line L2, whether or not the deceleration control can be executed on each of the first corner C11 and the second corner C12 depends on the passing speed at the corner. There is. This is because whether or not the behavior of the vehicle 1 is stabilized while traveling on the straight road C13 depends on the passing speed on the straight road C13. Accordingly, the deceleration control is executed by regarding the two front corners C11, C12 as independent corners, and the deceleration control is executed by regarding the first corner C11, the second corner C12 and the straight path C13 as one corner. Which is appropriate to do depends on the driving style of the driver.

  Further, for example, in a S-shaped composite corner or the like, the driver may travel while taking a straight line even if the shape of the runway is a curve. In this case, even if there is no section that is regarded as a straight road in the shape of the traveling road, there is a region that is regarded as a straight line in the traveling locus, and the behavior of the vehicle may be stabilized while traveling in that region. Therefore, when there is an area regarded as such a straight line, it is possible to perform traveling control as different corners on the near side and the far side of the area.

  In this embodiment, ECU20 determines the aspect of deceleration control according to the locus | trajectory of the vehicle 1 when it drive | worked the front runway in the past based on a driver | operator's driving | running | working log | history. Specifically, the ECU 20 performs deceleration control by regarding the preceding traveling path as one corner based on the curvature data of the past traveling locus on the preceding traveling path and the passing speed, or regarding a plurality of corners. It is determined whether to perform deceleration control for each corner. FIG. 4 is a diagram illustrating an example of a curvature distribution of a past travel locus. FIG. 4 shows a distribution diagram of curvature along the traveling direction of the traveling locus in the composite corner C1 shown in FIG. The curvature of the travel locus can have a different distribution depending on the driver or even the same driver depending on the passing speed. For example, the curvature distribution is different between a driver who drives the vehicle 1 along the route indicated by the broken line L1 and a driver who drives the vehicle 1 along the route indicated by the solid line L2. The curvature distribution shown in FIG. 4 relates to the driver who drives the vehicle 1 along the route (trajectory) indicated by the solid line L2, and is learned when the vehicle travels the composite corner C1.

  The ECU 20 sets an area where the magnitude of the curvature is equal to or less than a predetermined threshold (predetermined value) in the travel locus as an “area regarded as a straight line”. Specifically, when the curvature of the trajectory that curves to one side with respect to the traveling direction is positive and the curvature of the trajectory that curves to the other side is negative, an area in which the absolute value of the curvature is equal to or less than a threshold value (R0) It is determined that the area is regarded as a straight line. In addition, a region where the absolute value of the curvature is larger than the threshold value in the travel locus is determined as a curved region. In FIG. 4, symbol A3 corresponds to a region regarded as a straight line, and the region regarded as a straight line is indicated by symbol L23 in FIG. Reference numerals A1 and A2 correspond to the curved areas indicated by reference numerals L21 and L22 in FIG. 3, respectively. In this way, when the past trajectory L2 of the vehicle 1 on the forward running road has the region L23 regarded as a straight line and the two curved regions L21, L22 connected by the region L23 regarded as a straight line, It is predicted whether or not the behavior of the vehicle 1 is stabilized while traveling on the road in the region L23 regarded as a straight line from one of the curved regions L21 and L22 toward the other. As a result, when the behavior is predicted to be stable, the braking device 18 is controlled by using the two curved regions L21 and L22 as independent corners, and deceleration control is executed. When the behavior is not predicted to be stable, two Deceleration control is executed by controlling the brake device 18 with the curved areas L21 and L22 and the area L23 regarded as a straight line as one corner. As a result, it is possible to perform vehicle travel control in accordance with the driver's senses.

  Note that the curvature of the shape of the front traveling road may be used as the curvature of the front traveling road instead of the curvature data of the learned traveling locus. What is necessary is just to make it acquire from the information etc. which were previously memorize | stored in the map database 55 of the navigation apparatus 50, for example. As described above, when the curvature of the shape of the runway is used as the curvature of the forward runway, the “region regarded as a straight line” is the “section regarded as a straight road” on the forward runway, and the “curve region” is located on the forward runway. A “curve section” may be used. The determination method of the section regarded as a straight road can be the same as the determination method of the area regarded as a straight line. When using the curvature of the shape of the forward runway, if there is at least a running history related to the passing speed of the forward runway, it is possible to determine whether to recognize a plurality of corners or one according to the driving style of the driver. it can. It is also possible to predict the passing speed of the forward traveling road using the traveling history of the passing speed related to the traveling road similar to the forward traveling road.

  With reference to FIG. 1, the traveling control of the vehicle of this embodiment is demonstrated. The control flow shown in FIG. 1 has a region in which a past traveling locus on a traveling road ahead of the vehicle 1 is regarded as a straight line and two curved regions connected by a region regarded as a straight line. It is executed when it is recognized. The region regarded as a straight line may include a straight region having a curvature of zero. The predetermined value, which is a threshold value of the magnitude of curvature, is based on, for example, a curvature range in which the behavior of the vehicle 1 is stable during traveling. The predetermined value is determined in advance based on experimental results and the like as a magnitude of a curvature that allows the vehicle 1 to continue running with a stable behavior. Note that the behavior of the vehicle 1 being stable means that, for example, the roll size of the vehicle 1 is equal to or less than a predetermined roll amount. In this case, if the magnitude of the curvature is smaller than the predetermined value, the roll size of the vehicle 1 generated on the side G when traveling on the road is equal to or less than the predetermined roll amount.

  In step S <b> 1, the ECU 20 determines whether or not learning has already been performed on the road recognized forward. It is determined whether or not the vehicle has actually traveled on the road ahead and learned the curvature data and the speed change during the road travel. This learning result is stored in the driving history recording unit 56 of the navigation device 50. If it is determined as a result of the determination in step S1 that the road recognized ahead has been learned (step S1-Y), the process proceeds to step S2, and if not (step S1-N), the process proceeds to step S12. .

  In step S2, the ECU 20 sets an area regarded as a straight line. ECU20 acquires the curvature data of the past driving | running track regarding the front road track memorize | stored in the driving history recording part 56. FIG. This curvature data may be, for example, the value of curvature of each point on the trajectory along the traveling direction, or the value of curvature of each section when the trajectory is divided into a plurality of sections. The ECU 20 predicts the curvature distribution of the road along the traveling direction based on the curvature data. Based on the prediction result of the curvature, the ECU 20 sets, as a “region regarded as a straight line”, an area where the magnitude of the curvature is equal to or less than a predetermined threshold in the traveling locus.

  Next, in step S3, the vehicle speed is measured by the ECU 20. The ECU 20 measures the current vehicle speed before entering the front road by a signal indicating the detection result of the vehicle speed sensor 29.

Next, in step S4, the ECU 20 predicts the passage time of a region regarded as a straight line. ECU20 acquires the learning result of the speed change when it drive | worked the same runway in the past memorize | stored in the driving history recording part 56, and based on the present vehicle speed before the runway approach measured by step S3, the front runway Predict the passing speed (transition of speed along the trajectory) when passing. Instead of learning results on the same runway, the passing speed of the forward runway may be predicted based on the relationship between the curvature of the corner when passing through another corner and the passing vehicle speed. Based on the predicted passing speed of the forward traveling road and the length of the “region regarded as a straight line” set in step S2, the ECU 20 takes a time required for passing through the region regarded as a straight line by the following equation (1) ( Predict transit time).
Passing time = Length of the area regarded as a straight line ÷ Passing speed (1)

  Next, in step S5, the ECU 20 determines whether or not the transit time of the region regarded as a straight line is longer than the vehicle behavior stabilization time. The ECU 20 stores in advance information for obtaining a time required for the vehicle behavior to stabilize after entering the region regarded as a straight line (hereinafter simply referred to as “stabilization time”). The stabilization time is determined by the lateral G when passing through the road, the vehicle mass, the height of the center of gravity of the vehicle 1, the suspension characteristics, and the like, and the relationship between the combination of each parameter and the stabilization time is required based on experiments and the like in advance. . The lateral G at the time of passing through the road can be calculated based on the passing speed of the forward road predicted in step S4 and the curvature data of the running track related to the forward road.

  The ECU 20 stores the relationship between each parameter and the stabilization time as a map, for example, and calculates the stabilization time with reference to the map. In the present embodiment, “the vehicle behavior is stabilized” means that the roll size of the vehicle 1 is equal to or less than a predetermined roll amount. The stabilization time may be determined based on other values related to vehicle behavior. As a result of the determination in step S5, when it is determined that the transit time of the region regarded as a straight line is longer than the stabilization time of the vehicle behavior (the vehicle behavior is stabilized while traveling in the region regarded as a straight line) ( In step S5-Y), the process proceeds to step S6. Otherwise (step S5-N), the process proceeds to step S10.

  In step S6 to step S9, the ECU 20 executes the deceleration control as corners independent of each other across the “region regarded as a straight line” in a plurality of curved regions in the traveling locus relating to the forward traveling road. The corner shown in FIG. 3 will be described as an example. The ECU 20 regards the curved region L21 and the curved region L22 as corners that are independent of each other across a region L23 regarded as a straight line, and a curved region closer to the front than the region L23 regarded as a straight line. A target vehicle speed (target speed) is set for each of L21 and a curved region L22 on the far side of the region L23 regarded as a straight line. Based on the respective target vehicle speeds, the ECU 20 sequentially executes vehicle speed control by the brake device 18 (first deceleration control described later) for the curved region L21 and vehicle speed control (second deceleration control described later) by the brake device 18 for the curved region L22. To do.

  In step S6, the ECU 20 sets a control target position P1 and a target speed V1 for the first deceleration control. The control target position P1 and the target speed V1 are control targets for the first deceleration control that is the deceleration control for the curved region L21. In the first deceleration control, the deceleration control is performed so that the vehicle speed at the control target position P1 set for the curved region L21 is the target speed V1. When the control target position P1 and the target speed V1 are set, the process proceeds to step S7, and the first deceleration control is executed. In the first deceleration control, the ECU 20 controls the brake hydraulic pressure control device 19 so as to achieve the target speed V1 at the control target position P1. Note that the content of the deceleration control is not limited to this, and the speed reduction control by the automatic transmission 13 or the speed reduction control by the control of the engine braking force of the engine 11 may be performed. When step S7 is executed, the process proceeds to step S8.

  In step S8, the ECU 20 sets the control target position P2 and the target speed V2 for the second deceleration control. The control target position P2 and the target speed V2 for the second deceleration control are control targets for the second deceleration control that is the deceleration control for the curved region L22.

  Next, in step S9, the ECU 20 executes the second deceleration control. The ECU 20 controls the brake hydraulic pressure control device 19 so as to achieve the target speed V2 at the control target position P2. When step S9 is executed, the control flow ends.

  When a negative determination is made in step S5 and the process proceeds to step S10, the control target position P3 and the target speed V3 of the deceleration control are set by the ECU 20 in step S10. The ECU 20 regards the two curved areas L21 and L22 and the area L23 regarded as a straight line as one corner, and sets the control target position P3 and the target speed V3 for the whole corner. That is, one control target position P3 and target speed V3 are set for the composite corner C1. The target speed V3 is set based on, for example, the curve area having the larger curvature of the curve area L21 and the curve area L22.

  Next, in step S11, the ECU 20 performs deceleration control. The ECU 20 executes vehicle speed control by the brake hydraulic pressure control device 19 so as to realize the target speed V3 at the control target position P3 set in step S10. When step S11 is executed, the control flow ends.

  When a negative determination is made in step S1 and the process proceeds to step S12, in step S12, the trajectory, curvature, and passing speed are learned by the ECU 20 when passing the road. The ECU 20 learns the trajectory (coordinate value) of the traveling position of the vehicle 1 and the curvature and passing speed of each point on the trajectory while measuring the position of the host vehicle with GPS, INS (Inertial Navigation System) or the like. The curvature may be calculated based on detection results of the vehicle speed sensor 29, the steering angle sensor 33, the lateral G sensor 37, the yaw rate sensor 40, etc., or may be calculated based on the coordinate data of the locus of the positioning result. Good. The learning of the trajectory, the curvature, and the passing speed is executed each time the vehicle travels on the same track, the learning value is updated, and the learning is completed several times.

  Note that the vehicle travel control of the present embodiment is not limited to a spoon-cornered runway as shown in FIG. 3, and can be executed on other shaped runways, for example, an S-shaped corner. FIG. 5 is a diagram illustrating an example of a curvature distribution of a traveling locus in an S-shaped corner. Whether the front side and the back side of the region regarded as a straight line are regarded as a plurality of corners based on a traveling locus having a region regarded as a straight line and two curved regions connected by the region regarded as a straight line even in the S-shaped corner Therefore, it can be determined to match the driver's feeling as to whether it is regarded as one corner.

  As described above, according to the vehicle travel control system 1-1 of the present embodiment, a front corner is regarded as a plurality of independent corners based on the travel history (trajectory, curvature, passing speed, etc.) or one corner. It is determined whether it is considered. Since the travel control based on the number and shape of the corners determined according to the travel style of the driver is performed, the travel control of the vehicle according to the driver's sense is possible. Since the control is prevented from intervening at a position or timing that does not match the driver's sense (unexpected), the driver is prevented from feeling uncomfortable.

  In addition, the control content about the case where the curvature of a runway shape is used as the curvature of a runway ahead can be the same as the case where the curvature data of a running track is used. That is, if ECU20 has learned about the front runway with respect to the front runway which has a section regarded as a straight road and two curved sections connected by a section regarded as a straight road (step S1-Y). Set a section to be regarded as a straight road (step S2), measure the vehicle speed (step S3), and pass when traveling in a section regarded as a straight road from one of the curved sections to the other based on the driving history by the driver Predict time.

  If the passage time is longer than the stabilization time (step S5-Y), the first deceleration control is executed for the corner (first corner C11) on the near side of the section regarded as a straight road (step S6, S6). 7) Next, the second deceleration control is executed on the rear corner (second corner C12) (steps S8, 9). That is, with the two curved sections as independent corners, the target vehicle speed is set for each of the two curved sections, and the brake device 18 is controlled to execute vehicle speed control.

  If the passage time is equal to or less than the stabilization time (step S5-N), the composite corner C1 is regarded as one corner and the deceleration control is executed (steps S10 and S11). That is, two curve sections and a section regarded as a straight road are set as one corner, one target vehicle speed is set for one whole corner, the vehicle speed control is executed by controlling the brake device 18. Moreover, if it has not been learned about the forward running road (step S1-N), the running speed is acquired by learning the passing speed of the corner when passing the corner (step S12). As a result, even when the curvature of the road shape is used as the curvature of the road ahead, vehicle speed control is performed by determining the number of corners that can be regarded as independent corners on the road ahead according to the driving style of the driver. can do.

  In the present embodiment, the composite corner C1 existing on the forward running road is a straight road C13 that is a section regarded as one straight road, and the first corner C11 and the second curved section that are connected by the straight road C13. Although the case of having the corner C12 has been described, the number of sections regarded as a straight road that the composite corner C1 has and the number of curved sections are not limited to this. The composite corner C1 may have three or more curved sections, and two consecutive curved sections may be connected by sections regarded as straight roads.

  In the present embodiment, whether a section that is regarded as a straight road and two curved sections that are connected by a section that is regarded as a straight road are regarded as one unit section, and this unit section is regarded as one corner to control the driving state. It is determined whether to control the running state as a section having two independent corners. Therefore, even if the composite corner C1 has three or more curved sections, a unit section is extracted for each section regarded as a straight road for the composite corner C1, and the unit for each unit section is extracted. It is possible to determine whether to control the traveling state by regarding a section as one corner or to control the traveling state as a section having two independent corners. That is, in the vehicle travel control system 1-1 of the present embodiment, there is no restriction on the number of sections and the number of curve sections that are regarded as straight roads that the composite corner C1 has. Similarly, there is no restriction on the number of areas regarded as straight lines in the past trajectory or the number of curved areas.

(Modification of the embodiment)
In the above embodiment, the traveling state changing means for changing the traveling state of the vehicle 1 is the brake device (braking force changing means) 18, but is not limited to this, and the automatic transmission 13, the active suspension 31, the acceleration The changing means (engine 11 or the like) may function as the traveling state changing means. That is, as the vehicle running control at the corner, in addition to or instead of the deceleration control, for example, at least one of the shift control of the automatic transmission 13, the control of the active suspension 31, and the acceleration control may be executed. In the shift control of the automatic transmission 13, a shift control to a gear ratio suitable for traveling on a travel path including a curved section (a trajectory including a curved area) is performed. In the control of the active suspension 31, suspension characteristics suitable for traveling on a road including a curved section (a locus including a curved area) are controlled. Further, the acceleration control is executed at the time of escape from a corner (curved section, curved area) or the like. As the running state changed by the running state changing means, not only the vehicle speed but also the vehicle body posture or drivability estimated from the suspension or the stabilizer, or fuel consumption control may be used.

  As described above, the vehicle travel control system according to the present invention is useful for travel control of a travel path having a plurality of curved sections, and is particularly suitable for realizing travel control in accordance with the driver's feeling.

1-1 Vehicle Travel Control System 1 Vehicle 11 Engine 13 Automatic Transmission 18 Brake Device 19 Brake Hydraulic Control Device 20 ECU
C1 Composite corner C11 First corner C12 Second corner C13 Straight road L2 Traveling track (route)
L21, L22 Curve area L23 Area regarded as a straight line

Claims (5)

Traveling state changing means for changing the traveling state of the vehicle;
A control device for controlling the traveling state changing means according to a corner,
The control device, based on a driving history by the driver, for a forward road having a section regarded as a straight road and two curved sections connected by the section regarded as the straight road, When the behavior of the vehicle is predicted to be stable while traveling on the straight road from one side to the other, the traveling state changing means is controlled by using the two curved sections as the corners independent of each other. If the behavior of the vehicle is not predicted to be stable while traveling in the section regarded as the straight road based on the travel history, the two curved sections and the section regarded as the straight road are regarded as one corner. A vehicle travel control system characterized by controlling state change means. The traveling state changed by the traveling state changing means is a vehicle speed of the vehicle,
The control device performs vehicle speed control based on a target vehicle speed corresponding to the corner, and when the vehicle behavior is predicted to be stable while traveling in a section regarded as the straight road, the two curves When the target vehicle speed is set for each of the sections and vehicle speed control is performed by the traveling state changing means, and the vehicle behavior is not predicted to be stable while traveling in the section regarded as the straight road, the two curves The vehicle travel control system according to claim 1, wherein one target vehicle speed is set for a section and the entire section regarded as the straight road, and vehicle speed control is performed by the traveling state changing unit. The vehicle travel control system according to claim 1, wherein the section regarded as the straight road is a section in which a curvature has a predetermined value or less. The at least one of the braking force changing means for changing the braking force, the automatic transmission, the active suspension, and the acceleration changing means for changing the acceleration is provided as the running state changing means. Vehicle travel control system. Traveling state changing means for changing the traveling state of the vehicle;
A control device for controlling the traveling state changing means according to a corner,
The control device is based on a case where the past trajectory of the vehicle on the forward road has a region regarded as a straight line and two curved regions connected by the region regarded as the straight line based on the driving history of the driver. If the behavior of the vehicle is predicted to be stable while traveling in a region regarded as the straight line from one of the two curved regions toward the other, the two curved regions are defined as the corners independent of each other. If the behavior of the vehicle is not predicted to be stable while traveling in the region regarded as the straight line by controlling the traveling state change means, the two curved regions and the region regarded as the straight line are regarded as one corner. A vehicle travel control system characterized by controlling state change means.

Images