JP2011096103A - Driving support device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving support device for capable of driving support as a norm for enabling a self-vehicle to travel on a route, according to situations where the self-vehicle travels. <P>SOLUTION: An ECU 20 extracts the time change rate of each of parameters, corresponding to the road shapes of a route on which a self-vehicle 100 travels from a database in which the road shapes of the route and the time change rate of each of two or more parameters relating to movement on the route are associated with each other, and calculates a normative speed which is a norm for enabling the self-vehicle 100 to travel on the route, on the basis of the extracted time change rate of each of the parameters. Thus, it becomes possible to calculate the normative speed, on the basis of the time change rate of each of the two or more parameters relating to movement on the route corresponding to the road shapes of the route, and to provide the normative speed corresponding to the situations where the self-vehicle 100 travels. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a driving support device, and more particularly to a driving support device that performs driving support that is a standard for a host vehicle to travel on a route.

  2. Description of the Related Art Conventionally, there has been proposed an apparatus that provides information serving as a standard for a host vehicle to travel on a route. For example, Patent Document 1 discloses an apparatus that provides driving support information to a driver in a manner corresponding to the skill and confidence level of the driver. In this driving support device, the driving skill determining means for determining the driver's driving skill, the confidence level determining means for determining the confidence level for the driving skill based on the subjective evaluation of the driver, and based on the determined driving skill and confidence level. A providing mode determining unit that determines a mode for providing the driving support information acquired through the information acquiring unit, and a providing unit that provides the driver with the driving support information according to the determined mode. In this driving support device, the driving skill determination means includes a travel locus acquisition unit that acquires a travel locus of the host vehicle included in the vehicle information, a reference travel model acquisition unit that acquires a reference travel model of a road on which the vehicle travels, and And a driving skill calculation unit that calculates the driving skill of the driver based on a deviation degree of the traveling locus of the own vehicle with respect to the reference traveling model.

JP 2009-13496 A

  By the way, in the apparatus of Patent Document 1, a standard travel model of a road on which the vehicle travels is acquired, but the standard travel model is not necessarily a travel model in which the driver does not feel uncomfortable. For example, even if the vehicle travels at the same speed, the driving method in which the driver feels comfortable riding differs depending on the road shape on which the vehicle travels. Therefore, there is a demand for an apparatus that provides information serving as a standard for the vehicle to travel on the route according to the situation in which the vehicle travels.

  The present invention has been made in consideration of such circumstances, and its purpose is to provide driving assistance that serves as a standard for the vehicle to travel on the route in accordance with the situation in which the vehicle travels. It is in providing the driving assistance device which can do.

  The present invention obtains the time change rate of each parameter corresponding to the road shape of the route on which the vehicle travels from the database in which the road shape of the route and the time change rate of each of the two or more parameters related to movement on the route are associated with each other. A driving support apparatus comprising: extraction means for extracting; and reference speed calculation means for calculating a reference speed that is a reference for the vehicle to travel on the route based on a time change rate of each parameter extracted by the extraction means. It is.

  According to this configuration, the extraction unit uses the database corresponding to the road shape of the route and the time change rate of each of the two or more parameters related to the movement on the route, the parameter corresponding to the road shape of the route on which the vehicle travels. Each time change rate is extracted, and the reference speed calculation means calculates a reference speed as a reference for the vehicle to travel on the route based on the time change rate of each parameter extracted by the extraction means. The reference speed is calculated based on the time change rate of each of the two or more parameters relating to the movement on the route corresponding to the road shape of the route, and the reference speed according to the situation in which the vehicle travels is provided. Is possible.

  In this case, it is preferable that the time change rate of each parameter includes jerk, which is a value obtained by differentiating acceleration and acceleration of the own vehicle with respect to time.

  Jerk, which is a value obtained by differentiating acceleration and acceleration with respect to time, greatly affects the ride comfort of the vehicle. According to this configuration, the reference speed is calculated based on the acceleration and jerk corresponding to the road shape of the route. Accordingly, it becomes possible to calculate the reference speed with an emphasis on ride comfort according to the situation in which the host vehicle travels.

  In this case, the reference speed calculation means may calculate a reference acceleration that is a reference for the vehicle to travel on the route based on the acceleration and the jerk, and calculate a reference speed based on the calculated reference acceleration. Is preferred.

  According to this configuration, the reference speed calculation means calculates a reference acceleration that is a reference for the vehicle to travel on the route based on the acceleration and the jerk, and calculates a reference speed based on the calculated reference acceleration. Therefore, the reference speed can be calculated relatively easily.

  In this case, the reference speed calculation means calculates the reference acceleration that reaches the acceleration in the shortest time by accelerating / decelerating the vehicle by jerk, and the reference speed calculating means accelerates / decelerates by the reference acceleration that reaches the acceleration in the shortest time It is preferable to calculate the reference speed.

  According to this configuration, the reference speed calculation means calculates the reference acceleration that reaches the acceleration in the shortest time when the own vehicle performs acceleration / deceleration by jerk, and performs acceleration / deceleration by the reference acceleration that the vehicle reaches the acceleration in the shortest time. In order to calculate the reference speed when it is performed, the reference speed calculation means can calculate the reference speed that maximizes the movement efficiency on the route when the acceleration and jerk of the database are set as the limit values.

  In addition, the road shape of the route preferably includes the radius of curvature of the route.

  The radius of curvature of the route greatly affects the ride quality of the vehicle even when traveling at the same speed. However, according to this configuration, the road shape of the route includes the radius of curvature of the route. The reference speed is calculated based on the time change rate of each parameter corresponding to the radius of curvature of the route, and the reference speed with an emphasis on ride comfort can be calculated according to the situation where the host vehicle travels. It becomes possible.

  The extracting means extracts a time change rate of each parameter according to the driving skill of the driver of the own vehicle from the database, and the reference speed calculating means is based on the time change rate of each parameter extracted by the extracting means. It is preferable to calculate the reference speed according to the driving skill of the driver of the own vehicle.

  Even if the vehicle travels on the same route at the same speed, the rider feels different depending on the driver's driving skill, but according to this configuration, the extraction means can use the database according to the driver's driving skill from the database. In order to calculate the reference speed according to the driving skill of the driver of the own vehicle based on the time change rate of each parameter extracted by the extraction means. Thus, it is possible to calculate the reference speed taking into account the difference in ride comfort felt by the driver depending on the skill level.

  Further, it is preferable that the reference speed calculation means corrects the reference speed based on a difference between the speed when the host vehicle actually travels on the route and the reference speed.

  According to this configuration, the reference speed calculation means corrects the reference speed based on the difference between the speed at which the vehicle actually travels on the route and the reference speed, so the vehicle actually travels on the route. It is possible to robustly calculate the reference speed corresponding to the speed at the time of performing.

  In this case, the reference speed calculation means calculates the reference speed so that the vehicle actually arrives at a point on the route when the vehicle travels on the route at the reference speed. Is preferably corrected.

  According to this configuration, the reference speed calculation means allows the vehicle to actually reach a point on the route during the time it takes to reach a predetermined point on the route when the vehicle travels on the route at the reference speed. Therefore, even if the vehicle actually travels at a speed that deviates from the standard speed, the movement efficiency on the route can be made the same as when traveling at the standard speed.

  According to the driving support device of the present invention, it is possible to provide a reference speed according to the situation in which the host vehicle travels.

It is a block diagram which shows the structure of the driving assistance device which concerns on embodiment. It is a top view which shows the candidate of the path | pass which the own vehicle can take in an intersection. It is a flowchart which shows the outline of operation | movement of the driving assistance device which concerns on embodiment. It is a flowchart which shows the detailed operation | movement of the reference | standard vehicle speed plan of FIG. It is a top view which shows the relationship between the driving | running | working locus | trajectory and speed of the own vehicle. It is a perspective view which shows the vector space which prescribed | regulated the acceleration with respect to the curvature radius of a curve, and jerk. It is a perspective view which shows the vector space which interpolated to the vector space of FIG. It is a flowchart which shows the detailed operation | movement of the speed profile plan of FIG. It is a figure which shows the jerk, acceleration, speed, and position in the speed profile produced. It is a flowchart which shows the detailed operation | movement of the reference | standard vehicle speed correction | amendment of FIG. It is a graph which shows the relationship between a reference | standard speed, the vehicle speed of an actual own vehicle, a correction value, and a position.

  Hereinafter, a driving support device according to an embodiment of the present invention will be described with reference to the drawings. The driving support device according to the present embodiment is mounted on a vehicle and is a device for providing a standard speed to a driver of the host vehicle as a standard for riding on a route with good comfort. As shown in FIG. 1, the driving assistance device 10 of this embodiment includes a vehicle speed sensor 11, a direction indicator sensor 12, a radar sensor 13, a camera sensor 14, a navigation system 15, a road-to-vehicle communication device 16, a driver authentication unit 17, The ECU 20 includes actuators 31 and a display device 32.

  The vehicle speed sensor 11 is a sensor for detecting the speed of the own vehicle from the rotational speed of the axle of the own vehicle. From the speed detected by the vehicle speed sensor 11, an acceleration obtained by differentiating the speed with respect to time and a jerk obtained by differentiating the acceleration with respect to time are obtained.

  The direction indicator sensor 12 is for detecting the direction indicated by the direction indicator (blinker) of the host vehicle. The direction indicator sensor 12 is used for estimating the route of the host vehicle.

  The radar sensor 13 is for measuring the curvature radius of the road ahead of the host vehicle by, for example, irradiating millimeter waves ahead of the host vehicle. The camera sensor 14 images a road ahead of the host vehicle and measures the radius of curvature of the road ahead of the host vehicle by pattern recognition or the like.

  The navigation system 14 is for acquiring the radius of curvature of the road on which the vehicle travels based on the positioning of the vehicle by GPS (Global Positioning System) and the map information in the database. The navigation system 14 is also used to estimate the route of the host vehicle from information about the destination and route input by the driver.

  The road-to-vehicle communication device 16 is for acquiring information related to the curvature radius of the road ahead of the host vehicle from a roadside facility such as an optical beacon transmitter.

  The driver authentication unit 17 is for authenticating the driver who drives the vehicle and acquiring information related to the driving skill of the driver. The driver authentication unit 17 authenticates the driver by inputting a personal identification number or the like by the driver, inserting an ID card, or biometric authentication by identifying the driver's fingerprint, retina, iris, or the like. Information on the driving skill level of the driver can be acquired by the total driving distance, driving time, driving years, etc. of the driver.

  An ECU (Electronic Control Unit) 20 calculates a reference speed according to the curvature radius of the road ahead of the host vehicle and the skill level of the driver's driving based on information obtained from the vehicle speed sensor 11 and the like.

  The actuators 31 are brake actuators and accelerator actuators that intervene in the driving operation of the driver based on the reference speed calculated by the ECU 20 and drive the brakes and accelerators of the own vehicle. Further, the actuators 31 may be, for example, those that provide a reaction force against the driver's accelerator operation.

  The display device 32 is a display that displays an image to the driver, a speaker that provides voice guidance to the driver, and a buzzer that gives an alarm to the driver. The display device 32 is for presenting information based on the reference speed calculated by the ECU 20 to the driver.

  Hereinafter, operation | movement of the driving assistance device 10 of this embodiment is demonstrated. As a premise, the ECU 20 of the driving assistance apparatus 10 selects a route (path) on which the host vehicle travels. For example, in a situation where the vehicle 100 is about to enter an intersection as shown in FIG. 2, the predicted route of the vehicle is a route P1 that turns right at the intersection, a route P2 that goes straight through the intersection, and a route P3 that turns left at the intersection. There are three. The ECU 20 selects the route of the host vehicle 100 based on the direction indicated by the direction indicator from the direction indicator sensor 12 and information on the destination and route set by the driver in the navigation system 15. In the following description, it is assumed that the host vehicle 100 moves from a point a to a point b on a route P1 that turns right at an intersection.

  The driving support device 10 of the present embodiment is roughly divided into a step (S1) for planning a standard speed as shown in FIG. 3 and a step (S2) for correcting the planned standard speed. Hereinafter, the process of planning the reference speed will be described first. As shown in FIG. 4, the ECU 20 calculates the radius of curvature of the route along which the host vehicle 100 travels (S11). The radius of curvature of the route can be obtained based on the measurement values obtained by the radar sensor 13 and the camera sensor 14, the map information of the navigation system 15, and the information obtained from the road-vehicle communication device 16. As for the radius of curvature, information on the radius of curvature is obtained for each unit length of the path. In this case, the curvature radius information may be discrete, finite pieces of information such as large, medium, and small. The curvature radius information is calculated in advance and stored as data without using the road-to-vehicle communication device 16 or the like when the route of the vehicle 100 is determined in advance and the shape of the route is known. You may do it.

  The ECU 20 calculates speed, acceleration, and jerk limits as motion limit values (S12). Note that the speed in this case means a tangential speed V of the travel locus L of the vehicle 100 as shown in FIG. An acceleration is obtained by differentiating the velocity V with respect to time. The jerk is obtained by differentiating this acceleration with respect to time.

  As shown in FIG. 6, the ECU 20 previously stores data in which acceleration and jerk limits corresponding to the curvature radius R of the path are set in a three-dimensional space having the curvature radius R, acceleration, and jerk of the path as coordinate axes. ing. As shown in FIG. 6, the acceleration and jerk limits are set to the beginner tolerance limit BL set to the smallest value, the standard tolerance limit SL set to the medium value, and the largest value, respectively. Three veteran tolerance limits VL are set. The beginner tolerance limit BL, the standard tolerance limit SL, and the veteran tolerance limit VL are all set to smaller values as the radius of curvature R is smaller and the driver is more likely to feel discomfort even with a small acceleration or jerk.

  The data as shown in FIG. 6 can be created by measuring an actual measurement value in advance according to the skill level of the driver. As shown in FIG. 7, by acquiring discrete data D about the radius of curvature R, acceleration, and jerk, and drawing the curve I so as to interpolate them, the acceleration and the acceleration corresponding to various curvature radii R are obtained. It becomes possible to find the limit of jerk. The ECU 20 extracts the curvature radius R of the route calculated in S11 of FIG. 4 and the acceleration and jerk limits corresponding to the driving skill of the driver of the host vehicle 100 from the data shown in FIG. 7, and the host vehicle 100 travels. The acceleration and jerk limits of the path.

The ECU 20 plans a speed profile representing the reference speed as a function of time using the extracted acceleration and jerk limits. When the jerk limit is the maximum jerk j _max and the acceleration limit is the maximum acceleration a _max , the maximum acceleration a is obtained when acceleration is performed while maintaining the maximum jerk j _max until the time when the maximum acceleration a _max is reached. The time to reach _max is short and the movement efficiency is good. Therefore, as shown in FIGS. 8 and 9, the ECU 20 maintains the maximum jerk j _max until the time when the maximum acceleration a _max is achieved in the forward process when the host vehicle increases the speed. Is created (S131).

The ECU 20 calculates the time during which the maximum acceleration a _max is maintained in consideration of the deceleration time required to reach the maximum speed V _max at a constant speed (S132). Thereby, the acceleration profile in the forward process is created.

  The ECU 20 also creates an acceleration profile and a jerk profile indicating changes in acceleration and jerk over time in the reverse process at the time of deceleration when the host vehicle decreases the speed (S133). The ECU 20 joins the jerk profile and the acceleration profile created by the forward process and the reverse process (S134).

ECU20 integrates the acceleration profile, _{V 0} the initial values of the velocity V, and the final value by a _{V F,} creating a velocity profile (S135). The ECU 20 drives the actuators 31 with the speed related to the speed profile as the standard speed (speed command value), and displays the standard speed on the display device 32. Note that a position profile from point a to point b is created by integrating the velocity profile.

  Next, the process of correcting the planned reference speed will be described. As shown in FIGS. 10 and 11, the ECU 20 calculates a speed realization error that is a difference between the actual speed of the host vehicle 100 detected by the vehicle speed sensor 11 and the reference speed (S21). The ECU 20 corrects the speed command value according to the speed realization error (S22).

Hereinafter, the calculation of the speed realization error and the correction of the speed command value will be described in detail. Assume that the vehicle speed profile of the reference vehicle speed as shown in FIG. 11 is planned at the past time t _{1 as} shown in FIG. It is assumed that the actual speed of the vehicle 100 is y ₂ with respect to the speed command value x ₂ at time t ₂ after the sampling time T from time t ₁ . In this case, the ECU ₂₀ moves the distance between the area of the quadrangle t ₁ x ₁ x ₂ t ₂ in FIG. 11, that is, the movement distance based on the standard speed, and the area of the square t ₁ y ₁ y ₂ t ₂ , that is, the movement distance based on the actual speed. The difference ΔS is calculated.

At time t ₃ after sampling time T from time t ₂ , the ECU 20 determines the area (movement distance) of the movement distance difference ΔS + square t ₂ x ₂ x ₃ t _{3 and} the area of the square t ₂ y ₂ y ₃ t ₃ ( The reference speed x ₃ is corrected to y ₃ so that the movement distance) matches. That, ECU 20, in order to catch up with the first half of the time _t 1 ~t _2, revised upward norms speed as a target in the second half of the time _t 2 ~t _3.

  The ECU 20 determines whether or not the difference in distance between the sum of the moving distances based on the reference speed and the sum of the distances based on the actual speed is equal to or less than a predetermined value. Is added to the correction values in S21 and S22.

  According to this embodiment, ECU20 respond | corresponds to the road shape of the path | route which the own vehicle 100 drive | works from the database which matched the road shape of a path | route, and the time change rate of each of two or more parameters regarding the movement on a path | route. The time rate of change of each parameter is extracted, and based on the time rate of change of each extracted parameter, a standard speed that is a standard for the vehicle 100 to travel on the route is calculated. The reference speed is calculated based on the time change rate of each of the two or more parameters related to the movement on the route, and it is possible to provide the reference speed according to the situation where the host vehicle 100 travels.

  In particular, acceleration and jerk, which is a value obtained by differentiating acceleration with respect to time, have a great influence on the riding comfort of the vehicle. According to the present embodiment, the reference is based on the acceleration and jerk corresponding to the road shape of the route. The speed is calculated, and it becomes possible to calculate the standard speed that emphasizes the ride comfort according to the situation in which the host vehicle 100 travels.

  Furthermore, since the ECU 20 calculates a standard acceleration that is a standard for the host vehicle 100 to travel on the route based on the acceleration and the jerk, and calculates a standard speed based on the calculated standard acceleration, it is relatively easy. It becomes possible to calculate the reference speed.

  In addition, the ECU 20 calculates a reference acceleration that reaches the acceleration in the shortest time by the host vehicle 100 performing acceleration / deceleration by jerk, and a reference when the host vehicle performs acceleration / deceleration by the reference acceleration that reaches the acceleration in the shortest time. In order to calculate the speed, it is possible to calculate the reference speed that maximizes the movement efficiency on the route when the acceleration and jerk of the database are set as limit values.

  The radius of curvature of the route greatly affects the ride comfort of the vehicle even when traveling at the same speed. According to the present embodiment, the radius of curvature R of the route is included in the road shape of the route. Therefore, the reference speed is calculated based on the time change rate of each parameter corresponding to the radius of curvature R of the route, and the reference speed emphasizes ride comfort according to the situation where the host vehicle travels. Can be calculated.

  Further, even if the vehicle travels at the same speed on the same route, the rider feels different depending on the driver's driving skill, but according to the present embodiment, the ECU 20 is skilled in driving the driver of the host vehicle 100 from the database. The time rate of change of each parameter according to the degree is extracted, and based on the time rate of change of each extracted parameter, the standard speed according to the driving skill level of the driver of the host vehicle 100 is calculated. It is possible to calculate the reference speed taking into account the difference in ride comfort felt by the car.

  Further, since the ECU 20 corrects the reference speed based on the difference between the speed when the host vehicle 100 actually travels on the route and the reference speed, the ECU 20 sets the speed when the host vehicle 100 actually travels on the route. Correspondingly, the reference speed can be calculated robustly.

  Further, the ECU 20 corrects the reference speed so that the own vehicle 100 actually reaches the point on the route when the own vehicle 100 travels at the reference speed on the route and reaches the predetermined point on the route. Therefore, even if the vehicle 100 actually travels at a speed deviating from the standard speed, the movement efficiency on the route can be made the same as when traveling at the standard speed.

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Driving assistance device, 11 ... Vehicle speed sensor, 12 ... Direction indicator sensor, 13 ... Radar sensor, 14 ... Camera sensor, 15 ... Navigation system, 16 ... Road-to-vehicle communication device, 17 ... Driver authentication part, 20 ... ECU, 31 ... Actuators, 32 ... Display device, 100 ... Own vehicle, 200 ... Other vehicle.

Claims (8)

From the database in which the road shape of the route and the time change rate of each of two or more parameters related to movement on the route are associated, the time change rate of each of the parameters corresponding to the road shape of the route on which the vehicle travels is obtained. Extracting means for extracting;
A reference speed calculation means for calculating a reference speed as a reference for the vehicle to travel on the route based on the time change rate of each of the parameters extracted by the extraction means;
A driving assistance device comprising:   The driving support device according to claim 1, wherein the time change rate of each of the parameters includes an acceleration of the host vehicle and a jerk that is a value obtained by differentiating the acceleration with respect to time.   The reference speed calculation means calculates a reference acceleration as a reference for the vehicle to travel on the route based on the acceleration and the jerk, and calculates the reference speed based on the calculated reference acceleration. The driving support device according to claim 2.   The reference speed calculation means calculates the reference acceleration that reaches the acceleration in the shortest time by the host vehicle performing acceleration / deceleration by the jerk, and adds the acceleration by the reference acceleration that the vehicle reaches the acceleration in the shortest time. The driving support device according to claim 3, wherein the reference speed when the vehicle is decelerated is calculated.   The driving support device according to claim 1, wherein the road shape of the route includes a radius of curvature of the route. The extraction means extracts the time change rate of each of the parameters according to the driving skill of the driver of the own vehicle from the database,
The reference speed calculation means calculates the reference speed according to the driving skill of the driver of the host vehicle based on the time change rate of each of the parameters extracted by the extraction means. The driving support device according to any one of the above.   7. The reference speed according to claim 1, wherein the reference speed calculation unit corrects the reference speed based on a difference between a speed at which the host vehicle actually travels on the route and the reference speed. The driving assistance apparatus as described.   The reference speed calculation means is configured to allow the vehicle to actually reach the point on the route when the vehicle travels on the route at the reference speed and reaches a predetermined point on the route. The driving support device according to claim 7, wherein the reference speed is corrected so as to do.

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