JP2005227952A - Travel state advice system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a travel state advice system which preferentially displays a specific point where the degree of danger is high. <P>SOLUTION: The travel state advice system is equipped with: a road traffic information acquiring means 1 for acquiring road traffic information in the direction where a user's vehicle travels; a recommended speed estimating means 2 for calculating a recommended speed for a safe travel of the user's vehicle on a road based upon at least the road traffic information; a specific point extracting means 14 for extracting the specific point where the recommended speed changes on the road where the user's vehicle travels; an acceleration/deceleration calculating means 15 for calculating acceleration or deceleration needed for the user's vehicle to reach the recommended speed before reaching the specific point; an information presentation point selecting means 16 for selecting the specific point where the acceleration or deceleration is minimum as a specific point for presenting information to the driver of the user's vehicle; an information content control means 17 of controlling the contents of the information to be presented to the driver; and an information presenting means 4 for presenting the contents of the information to the driver. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a travel situation advice system, and more particularly to a travel situation advice system that calculates a recommended speed for a vehicle to travel safely on a road and presents the recommended speed to a driver.

  2. Description of the Related Art Conventionally, a display device for a vehicle that displays various information to a vehicle driver using a navigation device so that the vehicle can safely travel on a road is known (for example, Patent Documents). 1, see Patent Document 2).

  Patent Document 1 recommends that the navigation device detects the current position of the vehicle, obtains a curve on the road in the traveling direction of the vehicle, and smoothly passes through the curve in order to smoothly travel the curve. A vehicle display device that searches for a speed and displays a recommended speed area or the like on a speedometer screen is described.

Further, in Patent Document 2, when there are a plurality of curves on a road within a predetermined range in the traveling direction of the vehicle, when a predetermined caution / warning is issued to the driver about the curve through which the vehicle first passes, For the second and subsequent curves, there is described a travel safety device that prohibits caution / warning to alert the driver with appropriate frequency and improve the effectiveness of caution / warning.
JP-A-9-257507 (paragraph 0007, FIG. 6 etc.) JP 2002-367096 A (paragraph 0005 etc.)

  However, in the technique disclosed in Patent Document 1, even if the recommended speed region can be displayed, the acceleration / deceleration required to enter the curve after decelerating to the recommended speed region cannot be presented to the driver. There are cases in which it is not possible to grasp the amount of operation for a point at which the recommended speed changes, such as it is difficult to know whether to decelerate with strength.

  In the technique disclosed in Patent Document 2, when the second and subsequent curves have a higher degree of risk than the first curve, that is, when the recommended speed in the second and subsequent curves is slower than the first curve, 2 The warning / warning for the second and subsequent curves cannot be issued, and there is a risk of entering the second and subsequent curves without being able to decelerate to the recommended speed. For example, if there is a second curve that is steep after the gentle first curve, the second curve will be excluded from the display target when a warning / warning is issued for the first curve. Even if the vehicle is decelerated to the recommended speed of the first curve, the vehicle may not be able to travel safely because the vehicle is further decelerated to the recommended speed of the second curve that follows.

  A feature of the present invention is that road traffic information acquisition means for acquiring road traffic information in the direction in which the host vehicle travels and at least a recommended speed for the host vehicle to travel safely on the road based on the road traffic information. Required speed estimation means, specific point extraction means to extract specific points where the recommended speed changes on the road where the vehicle travels, and necessary for the speed of the vehicle to become the recommended speed by the time the specific point is reached An acceleration / deceleration calculating means for calculating the acceleration / deceleration, an information presentation point selecting means for selecting a specific point having the smallest acceleration / deceleration as a specific point for presenting information to the driver of the own vehicle, and a presentation to the driver A travel situation advice system having information content control means for controlling the content of information to be performed and information presentation means for presenting the content of information to the driver The gist.

  According to the present invention, the information presentation point selection means selects the specific point with the smallest acceleration / deceleration as the specific point for presenting information to the driver of the host vehicle, thereby giving priority to the specific point with a high degree of risk. It is possible to provide a driving situation advice system that displays automatically. Therefore, the driver decelerates the vehicle to the recommended speed at the specific point with the smallest acceleration / deceleration selected by the information presentation point selection means, so that the driver can sufficiently decelerate not only to the specific point but also to the recommended speed at other specific points. And can travel safely at all specific points.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

<Running situation advice system>
As shown in FIG. 1, the travel situation advice system according to the embodiment of the present invention is a system that presents appropriate travel speed information to the driver of the own vehicle according to the road shape and traffic situation around the own vehicle. Road traffic information acquisition means 1 for acquiring road traffic information in the direction in which the host vehicle travels, recommended speed estimation means 2 for calculating a recommended speed on the road on which the host vehicle travels based on at least the road traffic information, It has information control means 3 for controlling the content of information presented to the driver of the host vehicle based on the recommended speed, and information presentation means 4 for presenting the content of information to the driver. The road traffic information acquisition unit 1 includes a vehicle information detection unit 11, a navigation device 12, and a traffic flow detection unit 13.

  The “road traffic information” acquired by the road traffic information acquisition unit 1 includes road shapes and traffic conditions around the host vehicle. The recommended speed estimating means 2 is a recommended speed on the road in the traveling direction of the own vehicle based on at least one of the driver's driving skill (driving skill), vehicle performance, and the degree of familiarity with the driver's road in addition to the road traffic information. Is calculated. The information control means 3 is information based on the acceleration / deceleration required up to a specific point where the recommended speed changes from the estimation result of the recommended speed estimation means 2 and a threshold of acceleration / deceleration determined in advance according to the characteristics of the driver. Decide what to present.

  FIG. 2 shows a specific configuration of the travel situation advice system of FIG. The vehicle information detection means 11, the navigation device 12 and the traffic flow detection means 13 constituting the road traffic information acquisition means 1 of FIG. 1 are connected to each other by an in-vehicle LAN (local area network) 20. The recommended speed estimation means 2 and the information control means 3 in FIG. 1 form an information presentation control unit 5. The information presentation control unit 5 is connected to the in-vehicle LAN 20 and is connected to the information presentation means 4.

  The vehicle information detection means 11 detects various information related to the host vehicle such as the speed of the host vehicle (vehicle speed), the accelerator opening, and the brake on / off signal (brake SW). The navigation device 12 includes, for example, a map DB (database) 21 storing map data or road shape data using a storage medium such as a DVD, and an infrastructure receiver 22 as a vehicle position measuring device using GPS or autonomous navigation. The road information acquisition means 23 for acquiring the map data around the own vehicle by matching the positioning result of the current position of the own vehicle by the infrastructure receiver 22 on the road recorded in the map data and the like, and installed on the road Including an antenna and a converter for receiving information from an information providing infrastructure for a narrow range such as a beacon that has been received and an information providing infrastructure for a wide range such as FM multiplex broadcasting. Get traffic conditions. The traffic flow detection means 13 is composed of, for example, a laser radar 24, a millimeter wave radar, an in-vehicle camera 25, or the like. Detect relationships.

  The recommended speed estimation means 2 estimates the recommended speed according to the road shape and traffic flow using map data or road shape data around the own vehicle and information from the sensor group constituting the traffic flow detection means 13. The information control means 3 includes a specific point extracting means 14 for extracting a specific point where the recommended speed changes on the road, and an acceleration / deceleration necessary for the speed of the host vehicle to become the recommended speed by the time the specific point is reached. Acceleration / deceleration calculation means 15 for calculating, information presentation point selection means 16 for selecting a specific point with the smallest acceleration / deceleration as a specific point for presenting information to the driver of the own vehicle, and information presented to the driver Information content control means 17 for controlling the content of the information.

  The information presenting means 4 comprises a center console display 18 or an instrument panel display 19 provided for displaying a map of the navigation device 12, for example, and the information content controlled by the information content control means 17 is displayed by the driver. To present.

With reference to FIG. 3, the map data or road shape data stored in the map DB of FIG. 2 will be described. FIG. 3 is an example of map data or road shape data within a certain distance L _P in the traveling direction from the current position P0 of the host vehicle. The constant distance L _P can be set to a distance obtained by adding 200 m to the line-of-sight distance, for example, as shown in equation (1). V [km / h] indicates the vehicle speed.

L _P = 200 + V / 3.6 * 7.5 [m] (1)
The map data or road shape data stored in the map DB 21 of FIG. 2 is usually stored in the nodes N1, N2, N3,... And the complementary points Q ₁ , Q ₂ , Q ₃ ,. Point data and link data of a link (line) Li connecting them are provided. Here, the nodes N1, N2, N3,... Include the position coordinates of a point where there is a branch path such as an intersection or JCT, and the complementary points Q ₁ , Q ₂ , Q ₃ ,. The position coordinates of the point for drawing the road bend are included. Each point data and link data has attribute information. The point data attribute information includes information related to only that point, such as the curvature of the curve, signal, and whether or not there is a pause, and the link data attribute information includes road width, slope, speed limit, road type , Information that is continuous over a certain distance, such as the number of lanes. When the curvature information of the point data does not include the curvature of the curve, the curvature of the curve is calculated using the position coordinates of the points, the length of the link Li between the points, and the angle formed by the links Li before and after the point. You can also.

With reference to FIG. 4A and FIG. 4B, the recommended speed estimated by the recommended speed estimation means 2 of FIG. 2 will be described. The recommended speed estimation means 2 estimates the recommended speed V _n using map data or road shape data around the host vehicle and information on traffic flow. As shown in FIG. 4A, in the traveling direction (traveling scene) of the current position P0 of the host vehicle, there is a curve Li _B between the node N _B and the node N _C, and the node N _D and the node N _E It is necessary to pause at The node zone _F is ahead of the school zone Li _F. Recommended speed estimation unit 2, curve Li recommended speed V _C of the curve Li _B from the curvature of _B, recommended speed V _S at school zone Li _F, and other links Li _C, Li _D, the recommended speed V _l in Li _E Ask. Note that the recommended speed V _n in the temporary stop is zero. Further, the recommended speed V _C in the curve Li _B section can be obtained by using a table such that the recommended speed V _n increases as the curvature radius R of the curve increases as shown in FIG. 5A, for example. The recommended speed V _{n of the} section with a narrow road width can be obtained by using a table in which the recommended speed V _n increases as the road width W increases as shown in FIG. 5B, for example.

FIG 4 (b) as shown in, when the vehicle is traveling at a recommended speed V _l at the current position P0, the recommended speed V _l is the node N _B to be a boundary curve Li recommended speed V _C in _B To change. The recommended speed V _C changes to the recommended speed V ₁ in the link Li _C with the node N _C as a boundary. The recommended speed V _l temporarily changes to zero (recommended speed = 0) at the nodes (temporary stop) N _D and N _E. Recommended speed V _l is, changes in the node N _F on the border to the recommended speed V _S in the school zone Li _F. Thus, a point (node) where the recommended speed V _n changes on the road is called a “specific point”.

The specific point extraction means 14 extracts specific points (nodes N _B , N _C , N _D , N _E , N _F ) using the curvature calculated from the change in road attributes in the road shape data and the positional relationship between the nodes. .

For example, the recommended speed V _n is the front and rear a range of points that deceleration (e.g. 100m) curvature within is determined that the curve if the changes below 100R from above 300R, such road width reduced if the road width is reduced The specific point is determined as follows. Moreover, you may predict the change from independent driving | running | working to follow-up driving | running | working using the information regarding a traffic flow. For example, the following point (2) may be used to predict the transition to follow-up travel after Ts using the following equation (2), and the travel point after Ts may be set as the specific point.

Ts = D / Vr (2)
Note that the recommended speed V _{n at} a specific point is a standard acceleration / deceleration speed αd (for example, −2.5 [m / s ² ]) and an acceleration / deceleration speed αa (for example, +2.5 [m / s ² ]). The slope is changed. Here, the “acceleration / deceleration” is a physical quantity that takes a positive value when the speed of the host vehicle increases, that is, accelerates, and takes a negative value when the speed of the host vehicle decreases, that is, decelerates.

  Referring to FIGS. 6 and 7, a method for calculating the acceleration / deceleration necessary for the acceleration / deceleration calculation means 15 of FIG. 2 to reach the recommended speed by the time when each of the specific points is reached, and FIG. A method in which the second information presentation point selection means 16 selects the specific point with the smallest acceleration / deceleration as the specific point for presenting information to the driver of the host vehicle will be described.

FIG. 6 shows the current position of the host vehicle acquired by the road traffic information acquisition means 1, map data within a certain distance L _P (for example, within 500 m) from the current position, and the map data estimated by the recommended speed estimation means 2. The recommended speed and the specific point extracted by the specific point extracting means 14 are shown. The host vehicle is traveling at the vehicle speed V at the current position P0. On the road on which the host vehicle travels, there is a gentle right curve P1, followed by a steep left curve P2. After the left curve P2, there is a temporary stop P3 at the intersection of the T-junction. The recommended speed for the right curve P1 is V1, the recommended speed for the left curve P2 is V2, and the recommended speed for the temporary stop P3 is V3. Since the recommended speeds V1, V2, and V3 are different from each other, the nodes P1, P2, and P3 are specific points at which the recommended speed changes on the road.

FIG. 7 shows the acceleration / deceleration necessary for the speed of the host vehicle to change from the current vehicle speed V to the recommended speeds V1, V2, V3 by the time the host vehicle reaches the specific points P1, P2, P3 from the current position P0. 3 is a graph showing α1, α2, and α3. The acceleration / deceleration calculation means 15 calculates acceleration / deceleration α1, α2, α3 for each specific point P1, P2, P3 according to the equation (3). L represents the distance to the curve entrance from the vehicle position P0, V _n represents the recommended rate (n = 1~3).

α = (V ² -V _n ² ) / 2L (3)
Since all of the recommended speeds V1, V2, and V3 are lower than the current vehicle speed V, the acceleration / deceleration speeds α1, α2, and α3 are all negative values, that is, a deceleration operation is required. Since the recommended speeds V1 and V2 are faster than the recommended speed V3, the acceleration / deceleration speed α3 required for the temporary stop P3 farthest from the current position P0 is smaller than the acceleration / deceleration speeds α1 and α2. Therefore, in this case, the information presentation point selection means 16 uses the temporary stop P3 having the smallest acceleration / deceleration α3 as a specific point (hereinafter referred to as “information presentation point”) for presenting information to the driver of the host vehicle. select.

  With reference to FIGS. 8A to 8C, the information content control means 17 in FIG. 2 controls the content of information presented to the driver, and the information presentation means 4 in FIG. A method of presenting information contents to the hand will be described.

FIG. 8C shows the relationship between the information presentation point and the current position P0 of the host vehicle. Here, the left curve is selected as the information presentation point, and the host vehicle is traveling at the vehicle speed V. The recommended speed on the left curve is V _C. At time t1, yet, from the current position P0 ₁ of the vehicle to the left curve entrance is sufficiently far, over time, at time t2, t3, gradually left from the current position P0 _2, P0 ₃ of the vehicle Approach the curve entrance.

At this time, the acceleration / deceleration required until the left curve, which is the information presentation point, becomes smaller as time t1, t2, and t3 elapse as shown in FIG. That is, in order to decelerate from the current vehicle speed V to the recommended speed V _C , a stronger deceleration operation is required as the host vehicle approaches the left curve. 2 presets one or more acceleration / deceleration threshold values α _a , α _b ,..., And sets a warning / warning level for the driver based on these threshold values. Control.

Specifically, the vehicle position P0 ₁ at time t1 is larger and far enough away from the left-hand curve, also acceleration alpha required from the vehicle position P0 ₁ than the threshold value alpha _a of acceleration (α _a <α) In this case, as shown in <Display 1> in FIG. 8B, only the host vehicle speed V is displayed in the analog speedometer.

If the required acceleration or deceleration from the vehicle position P0 ₂ at time t2 is greater than the threshold value alpha _a smaller than alpha _b of acceleration _{(α b <α <α a} ), illustrated in <Display 2> shown in FIG. 8 (b) As described above, the difference between the own vehicle speed V and the recommended speed V _C is displayed in a sector area in the analog speedometer. Since this level (attention level) is a level for calling attention to the driver, it is desirable to display the fan-shaped area in yellow, for example.

Vehicle position P0 ₃ required acceleration from the threshold value alpha _a and threshold alpha _b is smaller than the acceleration at time _{t3 (α <α b <α} a) If, as shown in <Display 3> shown in FIG. 8 (b) In addition, the difference between the vehicle speed V and the recommended speed V _C is displayed in a sector area in the analog speedometer. Since this level (warning level) is a level that issues a warning to the driver, it is desirable to switch the display of the sector area from, for example, yellow to red. That is, the display is switched to a display prompting the driver to perform a strong deceleration operation as the left curve is approached.

  As described above, the information content control means 17 in FIG. 2 controls display contents such as display color, display area, and blinking speed. And the information presentation means 4 of FIG. 2 discriminate | determines whether the own vehicle passed the driving | running | working scene of the information presentation point, and when it passes, said yellow display or red display is complete | finished. In the traveling scene of the curve approach shown in FIG. 8C, the above caution / warning display may be terminated at the time of passing through the curve exit or when the accelerator is turned on in the curve section.

As the form of the information presentation regarding the recommended speed to be limited to the example of displaying the difference between the recommended speed V _C and the host vehicle speed V in sector region is not, it can also be used other forms. For example, in addition to the pointer indicating the vehicle speed V in the analog meter, a new pointer indicating the recommended speed V _C is newly added to alert the user first, and the new pointer color, thickness, length, blinking speed, etc. The level of attention / warning may be increased by changing stepwise or continuously. Alternatively, the caution / warning level may be adjusted by changing the size (radius) of the fan-shaped area stepwise or continuously, and the background display color of the entire analog meter is stepped from yellow to red. Alternatively, the caution / warning level may be adjusted by continuously changing.

<Driving status advice method>
Next, a travel situation advice method using the travel situation advice system shown in FIGS. 1 and 2 will be described with reference to FIG. The flowchart shown in FIG. 9 is executed at regular time intervals (for example, 100 ms). When the navigation device 12 has the function of the recommended speed estimation unit 2, the travel result recording function, and the driving tendency determination function, the main of the navigation device 12 is used. Called from the program.

(A) First, in step S01, the road traffic information acquisition unit 1 reads road attributes within a certain distance L _P from the current position P0 of the host vehicle. Specifically, map data and road shape data within a certain distance L _P in the traveling direction of the host vehicle (for example, within 500 m) are read from the map database 21 of the navigation device 12. The inter-vehicle distance and relative speed with respect to the preceding vehicle are acquired using the laser radar 24 and the in-vehicle camera 25 used in the traffic flow detecting means 13. Moreover, you may use the traffic information obtained from the VICS receiver mounted in the navigation apparatus 12 as information regarding a traffic flow.

(B) Next, in step S02, the specific point extracting means 14 extracts a specific point at which the recommended speed V _n changes on the road as described with reference to FIGS. 4 (a) and 4 (b). . In step S03, the recommended speed estimation means 2 calculates the recommended speed V _n using the map data and the like collected in step S01 and information relating to traffic flow.

(C) Next, in steps S04 to S06, the acceleration / deceleration calculation means 15 calculates the acceleration / deceleration α _n necessary for the speed of the host vehicle to reach the recommended speed V _n before reaching the specific point. Specifically, in the first S04 step, it calculates the speed difference V _{N_diff} the recommended speed V _n at the current velocity V and each specific point of the vehicle. In step S05, the distance L from the current position P0 of the host vehicle to each specific point is calculated. In step S06, the acceleration / deceleration α _n for each specific point is calculated using the speed difference V _{n_diff} and the distance L.

(D) Next, in step S07, the information presentation point selection means 16 selects a specific point that minimizes the acceleration / deceleration α _n as the information presentation point.

(E) Finally, in step S08, the information content control means 17 controls the content of information presented to the driver as described with reference to FIGS. 8 (a) to 8 (c). information presenting means 4, presents the content of the information (including the recommended speed V _n) with respect to the driver. Specifically, the information content control means 17 compares the acceleration / deceleration rate α _n at the information presentation point with the threshold _values α _a and α _b in FIG. 8A, and displays the warning / warning level (display color, display area, blinking rate). The information presenting means 4 displays the display contents such as the determined display color, display area, and blinking speed on the displays 18 and 19 in the center console or the instrument panel.

As described above, in the embodiment of the present invention, the acceleration / deceleration speed α and the recommended speed V _n required to reach the specific point where the recommended speed V _n changes are displayed to the driver, thereby specifying The driving operation amount (accelerator operation amount and brake operation amount) until reaching the point can be intuitively transmitted to the driver.

Further, according to the embodiment of the present invention, the information presentation point selection means 16 selects the specific point with the smallest acceleration / deceleration α as the specific point for presenting information to the driver of the own vehicle. It is possible to provide a travel situation advice system that preferentially displays a specific point with a high degree of risk. Therefore, the driver decelerates the vehicle to the recommended speed V _n at the specific point where the acceleration / deceleration α selected by the information presentation point selection means 16 is the smallest, so that the recommended speed not only at the specific point but also at other specific points is recommended. The vehicle can decelerate sufficiently to V _n and can travel safely at all specific points.

  In the embodiment, when the current speed V of the host vehicle is higher than the recommended speed Vn on the road in the traveling direction, that is, the acceleration / deceleration speed α is a negative value (a brake operation is necessary). However, the present invention is not limited to this. Needless to say, the present invention is applicable to the case where the current speed V of the host vehicle is smaller than the recommended speed Vn on the road in the traveling direction, that is, the acceleration / deceleration speed α is a positive value (acceleration operation is necessary).

  Further, the navigation apparatus 12 has functions equivalent to the recommended speed estimation means 2, the specific point extraction means 14, and the acceleration / deceleration calculation means 15, and the information content control means 17 has the function in the information presentation means 4. Thus, the information presentation control unit 5 of FIG. 2 may be configured to be distributed to the navigation device 12 and the information presentation means 4.

(First modification)
The travel situation advice system according to the first modified example further includes coefficient storage means for storing an acceleration / deceleration coefficient corresponding to a road attribute in addition to the configuration of the travel situation advice system shown in FIGS. Referring to FIGS. 10 to 12, a method for calculating an acceleration / deceleration necessary for the acceleration / deceleration calculation means 15 of FIG. 2 to reach the recommended speed by the time when each of the specific points is reached, and FIG. A method in which the second information presentation point selection means 16 selects a specific point having the smallest acceleration / deceleration considering the road attribute as the information presentation point will be described.

FIG. 10 shows the current position of the host vehicle acquired by the road traffic information acquisition means 1, the map data within a certain distance L _P from the current position, the recommended speed in the map data estimated by the recommended speed estimation means 2, and the identification The specific point extracted by the point extraction means 14 is shown. The host vehicle is traveling at the vehicle speed V at the current position P0. On the road on which the host vehicle travels, there is a gentle right curve P1, followed by a downward slope P2. After the downward slope P2, there is a traffic jam tail P3. The recommended speed on the right curve P1 is V1, the recommended speed on the downward slope P2 is V2, and the recommended speed at the tail end P3 of the traffic jam is V3. Since the recommended speeds V1, V2, and V3 are different from each other, the nodes P1, P2, and P3 are specific points at which the recommended speed changes on the road.

  FIG. 11 shows that the speed of the host vehicle changes from the current vehicle speed V to the recommended speeds V1, V2, V3 by the time when the host vehicle shown in FIG. 10 reaches the specific points P1, P2, P3 from the current position P0. It is a graph which shows required acceleration-deceleration (alpha) 1, (alpha) 2, (alpha) 3. The acceleration / deceleration calculation means 15 calculates acceleration / deceleration α1, α2, α3 for each specific point P1, P2, P3 according to the equation (3). Since all of the recommended speeds V1, V2, and V3 are lower than the current vehicle speed V, the acceleration / deceleration speeds α1, α2, and α3 are all negative values, that is, a deceleration operation is required. Since the recommended speeds V1 and V2 are faster than the recommended speed V3, the acceleration / deceleration α3 required for the traffic jam tail P3 farthest from the current position P0 is smaller than the acceleration / deceleration speeds α1 and α2.

  FIG. 12 is a table showing the acceleration / deceleration coefficient (Vb) stored in the coefficient storage means for each road attribute. For example, when the own vehicle is approaching a pedestrian or the like at the end of a traffic jam or crossing a road, there is a risk of colliding with a preceding vehicle or pedestrian unless the vehicle is sufficiently decelerated. On the other hand, if you are approaching a curved road, downhill road, narrow road, etc., there is a danger such as lane departure if you do not slow down sufficiently, but the level of danger is compared to the case of traffic jam end and pedestrians. not high. Therefore, as shown in FIG. 12, the priority (risk level) of the specific point is set in advance according to the attribute of the road, and this is stored in the coefficient storage means.

  The information presentation point selection means 16 shown in FIG. 2 multiplies the acceleration / deceleration coefficients α1, α2 and α3 calculated by the acceleration / deceleration calculation means 15 according to the equation (3) as acceleration / deceleration as shown in FIG. The values α1 ′, α2 ′, α3 ′ are used. That is, the information presentation point selection means 16 calculates the acceleration / deceleration rate α ′ considering the priority according to the road attribute of the specific point according to the equation (4), and presents the specific point with the smallest acceleration / deceleration rate α ′. Select as a point. Specifically, α1 ′, α2 ′, and α3 ′ are obtained according to equations (5) to (7).

α ′ = α × Vb (4)
α1 ′ = α1 × 0.8 (5)
α2 ′ = α2 × 0.5 (6)
α3 ′ = α3 × 1.2 (7)
Next, a travel situation advice method using the travel situation advice system according to the first modification will be described with reference to FIG. The flowchart shown in FIG. 13 is executed at regular time intervals (for example, 100 ms). When the navigation device 12 has the function of the recommended speed estimation means, the travel result recording function, and the driving tendency determination function, the main program of the navigation device 12 is used. It is called from. The flowchart shown in FIG. 13 is common to steps S01 to S06 and S08 of the flowchart shown in FIG.

(A) First, in step S01, the road traffic information acquisition unit 1 reads road attributes within a certain distance L _P from the current position P0 of the host vehicle.

(B) Next, in step S02, the specific point extracting means 14 extracts a specific point at which the recommended speed V _n changes on the road as described with reference to FIGS. 4 (a) and 4 (b). . In step S03, the recommended speed estimation means 2 calculates the recommended speed V _n using the map data and the like collected in step S01 and information relating to traffic flow.

(C) In the next S04 step, acceleration calculating unit 15 calculates the speed difference V _{N_diff} the recommended speed V _n at the current velocity V and each specific point of the vehicle. In step S05, the acceleration / deceleration calculation means 15 calculates the distance L from the current position P0 of the host vehicle to each specific point. In step S06, the acceleration / deceleration calculation means 15 calculates the acceleration / deceleration α _n for each specific point using the speed difference V _{n_diff} and the distance L.

(D) Next, in step S070, the information presentation point selection means 16 multiplies each acceleration / deceleration α _n by an acceleration / deceleration coefficient Vb corresponding to the road attribute as shown in the table of FIG. The velocity α _n ′ is calculated respectively. In step S075, the information presentation point selection unit 16 selects a specific point having the minimum acceleration / deceleration α _n ′ as the information presentation point.

(E) Finally, in step S08, the information content control means 17 controls the content of information presented to the driver as described with reference to FIGS. 8 (a) to 8 (c). information presenting means 4, presents the content of the information (including the recommended speed V _n) with respect to the driver.

  As described above, in the first modification, the information presentation point selection unit 16 performs the road attribute of each specific point shown in FIG. 12 with respect to the acceleration / deceleration α at each specific point calculated according to the equation (3). An information presentation point is selected by using a value α ′ multiplied by a priority (acceleration coefficient: Vb) according to. This makes it possible to present to the driver information (traveling situation advice) that takes into account priorities according to road attributes.

(Second modification)
The travel situation advice system according to the second modification is the same as the configuration of the travel situation advice system shown in FIGS.

With reference to FIG. 14, the processing operation of the information presentation point selection unit 16 in FIG. 2 when a plurality of specific points includes a specific point that requires an acceleration operation with respect to the current vehicle speed will be described. FIG. 14 shows the current position of the host vehicle acquired by the road traffic information acquisition means 1, the map data within a certain distance L _P from the current position, the recommended speed in the map data estimated by the recommended speed estimation means 2, and the identification The specific point extracted by the point extraction means 14 is shown. The host vehicle is traveling at the vehicle speed V at the current position P0. On the road on which the host vehicle travels, there is a gentle right curve P1, followed by a merging point P2. After the junction point P2, there is a steep left curve P3. The recommended speed for the right curve P1 is V1, the recommended speed for the junction point P2 is V2, and the recommended speed for the left curve P3 is V3. Since the recommended speeds V1, V2, and V3 are different from each other, the nodes P1, P2, and P3 are specific points at which the recommended speed changes on the road. The recommended speed V2 at the junction point P2 is greater than the vehicle speed V. Therefore, the acceleration / deceleration α2 at the junction point P2 is a positive value greater than zero, and the junction point P2 is an acceleration point for the host vehicle running at the vehicle speed V. Furthermore, another specific point P1 exists between the merging point P2 serving as an acceleration point and the current position P0 of the host vehicle.

  In this way, the specific points extracted by the specific point extracting means 14 include specific points (acceleration points) with acceleration / deceleration α greater than zero, and other points between the current position of the host vehicle and the acceleration points. When the specific point exists, the information presentation point selection means 16 selects the specific point having the smallest acceleration / deceleration α among the other specific points as the information presentation point.

Specifically, a right curve P1 exists between the merge point P2 and the current position P0 of the host vehicle. Therefore, the information presentation point selection means 16 selects the right curve P1 as the information presentation point. FIG. 14 shows a case where there is only one specific point (right curve P1) between the merging point P2 and the current position P0 of the host vehicle, but a plurality (n) of specific points P1 _{1 to} P1 are shown. _n may be present. In this case, the information presentation point selection means 16, from the n-number of specific points P1 ₁ to P1 _n, selects the smallest specific point acceleration α is information presentation point to.

  The specific points extracted by the specific point extracting means 14 include specific points (acceleration points) whose acceleration / deceleration is greater than zero, and other specific points exist between the current position of the host vehicle and the acceleration points. When it does not exist, the information presentation point selection means 16 selects the acceleration point as the information presentation point. That is, in this case, the travel situation advice system according to the second modification issues a caution / warning that prompts the driver to perform an accelerator operation.

  Next, a travel situation advice method using the travel situation advice system according to the second modification will be described with reference to FIG. The flowchart shown in FIG. 15 is executed at regular time intervals (for example, 100 ms), and the main program of the navigation device 12 when the navigation device 12 has the function of the recommended speed estimation means, the travel result recording function, and the driving tendency determination function. It is called from. In addition, since the flowchart shown in FIG. 15 shares steps S01 and S03 to S08 of the flowchart of FIG. 9, detailed description thereof is omitted.

(A) First, in step S01, the road traffic information acquisition unit 1 reads road attributes within a certain distance L _P from the current position P0 of the host vehicle.

(B) Next, in step S020, the specific point extraction unit 14 determines whether or not there is a specific point that is an acceleration point (for example, a merge point) with respect to the host vehicle that is traveling at the vehicle speed V within the fixed distance L _P. to decide. When there is an acceleration point (YES in step S020), the process proceeds to step S026, and the specific point extracting unit 14 extracts another specific point existing between the current position of the host vehicle and the acceleration point. If there is no acceleration point (NO in step S020), the process proceeds to step S023, and the specific point extracting unit 14 extracts a specific point within a certain distance L from the current position of the host vehicle. In step S03, the recommended speed estimation means 2 calculates the recommended speed V _n using the map data and the like collected in step S01 and information relating to traffic flow.

(C) In the next S04 step, acceleration calculating unit 15 calculates the speed difference V _{N_diff} the recommended speed V _n at the current velocity V and each specific point of the vehicle. In step S05, the acceleration / deceleration calculation means 15 calculates the distance L from the current position P0 of the host vehicle to each specific point. In step S06, the acceleration / deceleration calculation means 15 calculates the acceleration / deceleration α _n for each specific point using the speed difference V _{n_diff} and the distance L.

(D) Next, in step S07, the information presentation point selection means 16 selects a specific point that minimizes the acceleration / deceleration α _n as the information presentation point.

(E) Finally, in step S08, the information content control means 17 controls the content of information presented to the driver as described with reference to FIGS. 8 (a) to 8 (c). information presenting means 4, presents the content of the information (including the recommended speed V _n) with respect to the driver.

  As described above, when the acceleration point is within a certain distance (current position of the host vehicle), the travel situation advice system according to the second modification is subject to processing at another specific point before the acceleration point. Then, a specific point that requires the smallest acceleration / deceleration α is selected as an information presentation point, and a predetermined display is performed. If there is no other specific point before the acceleration point, the acceleration point is selected as an information presentation point. Therefore, appropriate advice can be provided to the driver even in a driving situation in which acceleration points and deceleration points are mixed.

  As described above, the present invention has been described by way of one embodiment and modifications thereof. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. That is, it should be understood that the present invention includes various embodiments not described herein. Therefore, the present invention is limited only by the invention specifying matters according to the scope of claims reasonable from this disclosure.

It is a block diagram which shows the outline | summary of the driving | running | working condition advice system concerning embodiment of this invention. It is a block diagram which shows the specific structure of the driving | running | working condition advice system shown in FIG. An example of map data or road shape data stored in the map DB of FIG. 2 is shown. FIG. 4A is a schematic diagram showing an example of the recommended speed estimated by the recommended speed estimating means of FIG. 2, and FIG. 4B is a graph showing a change in the recommended speed in FIG. . FIG. 5A is a graph showing the relationship between the curvature radius of the curve and the recommended speed, and FIG. 5B is a graph showing the relationship between the road width and the recommended speed. It is a figure which shows the example of a specific point in case a some curve exists on the road within the fixed distance of the advancing direction of the own vehicle. It is a graph which shows the acceleration / deceleration required in order for the speed of the own vehicle to become a recommended speed by the time of reaching each specific point shown in FIG. FIG. 8A is a graph showing the relationship between the acceleration / deceleration required up to a specific point (information presentation point) for presenting information to the driver of the host vehicle and the caution / warning level for the driver. (B) is a figure which shows the example of a warning / warning display by an information presentation means, and FIG.8 (c) is a figure which shows the distance from the present position of the own vehicle to an information presentation point. It is a flowchart which shows the driving | running | working condition advice method using the driving | running | working condition advice system shown in FIG.1 and FIG.2. It is a figure which shows the example in connection with the 1st modification of embodiment and when there exist several specific points on the road within the fixed distance of the advancing direction of the own vehicle. It is a graph which shows the acceleration / deceleration required in order for the speed of the own vehicle to become a recommended speed by the time of reaching each specific point shown in FIG. It is a table | surface which shows the acceleration-deceleration coefficient according to the attribute of the road memorize | stored in the coefficient memory | storage means concerning a 1st modification. It is a flowchart which shows the driving | running | working condition advice method using the driving | running | working condition advice system concerning a 1st modification. It is a figure which shows the example in case there exist a plurality of specific points including the specific point which needs acceleration operation on the road within the fixed distance of the advancing direction of the own vehicle in connection with the 2nd modification of embodiment. It is a flowchart which shows the driving | running | working condition advice method using the driving | running | working condition advice system concerning a 2nd modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Road traffic information acquisition means 2 ... Recommended speed estimation means 3 ... Information control means 4 ... Information presentation means 5 ... Information presentation control unit 11 ... Vehicle information detection means 12 ... Navigation apparatus 13 ... Traffic flow detection means 14 ... Specific point extraction Means 15 ... Acceleration / deceleration calculation means 16 ... Information presentation point selection means 17 ... Information content control means 18 ... Center console display 19 ... Instrument panel display 20 ... In-vehicle LAN
DESCRIPTION OF SYMBOLS 21 ... Map database 22 ... Infrastructure receiver 23 ... Road information acquisition means 24 ... Laser radar 25 ... In-vehicle camera αa, αb ... Acceleration / deceleration threshold value α1-α3, αn, αd ... Acceleration / deceleration L _P ... Fixed range L ... Distance Li ... link N1, n _B to n _F ... node _{P0, Y, Y 1 ~Y 3} ... current position P1 ₁ to P1 _n ... specific point Q _1, Q ₂ of the vehicle, ... ... interpolation points R ... radius of curvature V1 to _V3 , V _C , V _S , V _n ... recommended speed V _{n_diff} ... speed difference V ... own vehicle speed Vb ... acceleration / deceleration coefficient W ... road width t1 to t3 ... time

Claims (4)

Road traffic information acquisition means for acquiring road traffic information in a direction in which the host vehicle travels;
Recommended speed estimation means for calculating a recommended speed on a road on which the host vehicle travels based on at least the road traffic information;
Specific point extracting means for extracting a specific point at which the recommended speed changes on the road;
Acceleration / deceleration calculation means for calculating an acceleration / deceleration necessary for the speed of the host vehicle to become the recommended speed by the time when the specific point is reached;
Information presentation point selection means for selecting the specific point with the smallest acceleration / deceleration as a specific point for presenting information to the driver of the host vehicle;
Information content control means for controlling the content of the information presented to the driver;
A travel situation advice system comprising: information presenting means for presenting the content of the information to the driver. Coefficient storage means for storing an acceleration / deceleration coefficient corresponding to the road attribute,
2. The travel situation advice system according to claim 1, wherein the information presentation point selection means uses, as the acceleration / deceleration, a value obtained by multiplying the acceleration / deceleration by the acceleration / deceleration coefficient.   The specific point extracted by the specific point extracting means includes a specific point having an acceleration / deceleration greater than zero, and another specific point between the own vehicle and the specific point having an acceleration / deceleration greater than zero. 3. The travel situation advice system according to claim 1, wherein, when present, the information presentation point selection unit selects a specific point having the smallest acceleration / deceleration among the other specific points.   The specific point extracted by the specific point extracting means includes a specific point having an acceleration / deceleration greater than zero, and another specific point between the own vehicle and the specific point having an acceleration / deceleration greater than zero. 3. The travel situation advice system according to claim 1, wherein when there is no information, the information presentation point selection means selects a specific point with the acceleration / deceleration greater than zero.