JP2005149024A - Onboard information providing device for drive support - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an onboard information providing device for drive support that provides information to a driver at the appropriate timing according to the speed of one's own vehicle. <P>SOLUTION: A desired vehicle speed Vrs is calculated from the product of speed limit information Vlim for the road on which the one's own vehicle is traveling and a coefficient Krs set according to the condition of the road surface, and the deceleration distance Lrs needed to decelerate to the desired speed Vrs is calculated (step S1-S5). A point that is the deceleration distance Lrs ahead of a change point of the condition of the road surface is set as the timing to provide information (step S6). Information is provided at the point (step S7). When the one's own vehicle is traveling on a road where speed limit is high, the desired vehicle speed Vrs is relatively high. Conversely, when it is traveling on a road where speed limit is low, the desired vehicle speed Vrs is relatively low. Because the desired vehicle speed Vs matching the speed of the one's own vehicle is thus set, information is provided at the timing matching the desired vehicle speed Vrs, whereby information is provided at the timing matching the speed of the one's own vehicle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention obtains traveling environment information on a road ahead of the traveling direction of the host vehicle, and based on the traveling environment information, allows the driver to recognize the traveling environment ahead of the host vehicle in advance. The present invention relates to an in-vehicle information providing apparatus.

Conventionally, as this type of technology, for example, a road shape such as a curve in front of the host vehicle, obstacles existing on the road, road surface condition of the traveling road surface, etc. are detected by an infrastructure system arranged on the road side, Information in which information detected by this infrastructure system is transmitted as infrastructure information to a system mounted on the vehicle side by road-to-vehicle communication or the like has been proposed.
In this way, the infrastructure system arranged on the road surface side informs the driver in advance of the current road surface state, road shape, etc., so that the driver is alerted and an alarm is generated. I have to.
For example, based on the road surface state notified as infrastructure information and the position of the change point of the road surface state, the braking distance required by the host vehicle is predicted, and the distance to the preceding vehicle is a safe inter-vehicle distance A device that generates an alarm or controls a vehicle has been proposed (for example, Patent Document 1).
JP 2002-163793

By the way, in the above conventional method, the safe inter-vehicle distance is set only from the road surface state, and based on this, the driving state target values such as the target vehicle speed and the target deceleration are determined. In general, the timing of providing information such as alerting the driver is determined according to the required braking distance required when the vehicle is decelerated from the current vehicle speed to the target vehicle speed with a predetermined deceleration in consideration of the driver's reaction time. .
Here, for example, when the information is provided when the distance to the change point of the road surface condition becomes the necessary braking distance, when traveling on a general road with a relatively low traveling speed, Since the required braking distance is calculated to be relatively short, the information providing timing is relatively late. Conversely, when traveling on a highway with a high traveling speed, the information provision timing is advanced because the necessary braking distance is calculated to be relatively long.

  For this reason, for example, when traveling on a highway with a high traveling speed, information is provided at a relatively early timing, so that information is provided at a point relatively distant from the change point of the road surface condition. Depending on the driver, the driver may feel that the information provision timing is early, or even if the deceleration operation is performed at this time, the driver does not know how much the deceleration operation should be performed, and the driver appropriately determines the deceleration rate. In some cases, the driver feels uncomfortable with respect to the information provision timing.

  Conversely, when driving on a general road with a low traveling speed, information is provided at a relatively late timing, and information is provided at a point relatively close to the changing point of the road surface condition. May feel that the information provision timing is too late, etc., and the information provision timing does not conform to the actual driving situation, and it is not possible to provide information to the driver at an appropriate timing, which makes the driver feel uncomfortable There is a problem that there are cases.

Also, in general, the vehicle tends to accelerate on a downward slope, so the driver's deceleration tends to be insufficient, and conversely, on an upward slope, the vehicle tends to decelerate regardless of the driver's deceleration operation. Become. For this reason, even if the deceleration operation is started at the timing when the information is provided, the deceleration used in the calculation of the deceleration operation timing is different from the actual deceleration. During this period, the driver has to adjust the deceleration according to the gradient, and there is still a problem that the driver feels uncomfortable.
Therefore, the present invention has been made paying attention to the above-mentioned conventional unsolved problems, and is for driving support capable of providing information to the driver at an appropriate timing according to the traveling state of the host vehicle. The object is to provide an in-vehicle information providing apparatus.

In order to achieve the above object, the in-vehicle information providing apparatus for driving support according to the present invention obtains information related to the traveling environment such as the road surface condition of the information provision target section ahead of the host vehicle by an information obtaining unit in advance. Notify passengers in advance.
At this time, speed limit information on the travel path of the host vehicle is detected by the travel path information detection means, and a travel state target until the host vehicle reaches the information provision target section based on the speed limit information and the travel environment information. A value is calculated, the timing at which the traveling state of the host vehicle can become the traveling state target value by the information provision target section is calculated by the timing calculation means, and information is provided to the occupant at the calculated information provision timing.

  Here, since the driving state target value is set based on the speed limit information and the driving environment information, when the host vehicle is driving on a highway, for example, according to the speed limit of the highway. When driving on a general road with a relatively large value, the driving state target value is set to a relatively small value according to the speed limit of the general road, that is, the traveling speed state of the host vehicle The running state target value is calculated according to the above. Therefore, since information is provided at a timing corresponding to the travel state target value, information is provided at a timing according to the travel speed state of the host vehicle.

  As described above, according to the in-vehicle information providing apparatus for driving support according to the present invention, the driving state target value is set based on the speed limit information and the driving environment information. It is possible to set a driving state target value in accordance with the state. Therefore, since information is provided at a timing according to the target value of the driving state, it is possible to provide information at a timing according to the driving speed state of the host vehicle, which is too early or too late depending on the driving state. Information can be provided at an appropriate timing without any problems.

Embodiments of the present invention will be described below.
First, a first embodiment will be described.
FIG. 1 is a schematic configuration diagram showing an example of an in-vehicle information providing apparatus 100 to which the present invention is applied.
In FIG. 1, 1 communicates with an infrastructure system 200 (described later) disposed on the road side to acquire road information of a road surface state detection section ahead of the current traveling point as infrastructure information. 2 is a navigation system, and the infrastructure information acquired by the in-vehicle wireless device 1 and the navigation information from the navigation system 2 are input to the information providing controller 3. .

The navigation system 2 detects the position of the own vehicle by GPS, and detects the speed limit of the traveling road of the own vehicle as traveling path information based on the detected position of the own vehicle and map information previously mounted. This is output to the information providing controller 3.
The information providing controller 3 inputs the infrastructure information from the in-vehicle wireless device 1, the travel route information from the navigation system 2, and the vehicle speed detected by the vehicle speed detection means 2a such as a vehicle speed sensor, and the infrastructure information The timing for providing information to the driver based on the travel route information and the vehicle speed is set, the information providing device such as the display 4 and the speaker 5 provided in the vicinity of the driver's seat is operated, The driver is notified of the road surface state ahead of the host vehicle at the information provision timing by voice guidance from the speaker 5.

As this road surface state, for example, it is notified of any one of five stages of “freezing”, “snow accumulation”, “water film”, “wet”, and “dry”.
As shown in FIG. 1, the information providing controller 3 includes a travel target value calculation unit 3 a and an information provision timing calculation unit 3 b, and the travel target value calculation unit 3 a is travel route information from the navigation system 2. Based on the vehicle speed, a target speed when the host vehicle passes a road surface state detection section described later and a target deceleration from the current position to the road surface state detection section start point are calculated. In addition, the information provision timing calculation unit 3b calculates an information provision start point for providing information to the driver according to the road surface state of the road surface state detection section.

  FIG. 2 shows an example of an infrastructure system 200 arranged on the road surface side for providing information to the in-vehicle information providing apparatus 100. In FIG. A road surface sensor for detecting a road surface state such as a camera or a temperature sensor, 12 is a data processing device for generating predetermined transmission data based on detection information of the road surface sensor 11, and 13 is generated by the data processing device 12. A radio wave beacon for transmitting transmission data including road surface information by wireless communication, and the radio wave beacon 13 is disposed on the upstream side of the traveling road with respect to the road surface state detection section.

One or a plurality of the road surface sensors 11 are disposed at positions where the road surface condition of the road surface state detection section set in the traveling road ahead of the host vehicle is possible, for example, where the road surface is likely to freeze or puddles. Detection information of the sensor 11 is input to the data processing device 12.
The data processing device 12 estimates a road surface state of a road surface state detection section based on a road surface reflection state and a road surface temperature specified from detection information such as image information and temperature information from the road surface sensor 11. As the road surface state, for example, five stages of “freezing”, “snow accumulation”, “water film”, “wet”, and “dry” are estimated. And various transmission data, such as this road surface state, transmission data which consists of road information, such as the distance from the road surface sensor 11 to the radio beacon 13, and transmission data which consists of control information etc., are produced | generated. Then, the data processing device 12 generates transmission data at a predetermined cycle and transmits it.

  As described above, the data processing device 12 generates transmission data at a predetermined cycle based on detection information such as the road surface state detected by the road surface sensor 11, and the radio wave beacon 13 transmits the transmission data. Road-to-vehicle communication is performed between the wireless device 1 and the radio wave beacon 13, and road surface information such as road surface conditions is notified to the vehicle side. Thus, the driver determines the road surface state of the road surface to be traveled in advance. Can be recognized. Although not shown in FIG. 2, a base point beacon for notifying the start of the information providing service is arranged upstream of the radio wave beacon 13 on the own vehicle traveling path, and the data processing device 12, when infrastructure information is received from the radio wave beacon 13, the infrastructure information is processed as valid information.

FIG. 3 is a flowchart showing an example of the processing procedure of the information providing process executed when the information providing controller 3 provides information to the driver based on the infrastructure information.
When the in-vehicle wireless device 1 receives the infrastructure information from the radio wave beacon 13 disposed on the road side, the process proceeds from step S1 to step S2, and the received infrastructure information includes road information including road surface information in front of the host vehicle. Whether or not is included. For example, when the data processing device 12 generates transmission data including road information, the determination is performed by adding identification information such as a header identifier that can identify road information, and transmitting infrastructure information. The received information providing controller 3 determines whether the infrastructure information includes road information by determining whether the identification information is identification information representing road information.

  If the road information is not included, the process directly returns to step S1, and if the road information is included, the process proceeds to step S3. In this step S3, the own vehicle moving distance LV is reset, and measurement of the own vehicle moving distance LV is started. This own vehicle moving distance LV represents the moving distance from the distance origin with the traveling position of the own vehicle at the time of receiving the infrastructure information from the radio wave beacon 13, and represents the moving distance from the distance origin. The measurement is executed in a processing routine different from the information providing process of FIG. 3, and is calculated based on the following equation (1) at every predetermined sampling time.

In Equation (1), Vh is the vehicle speed, ST is the sampling time, and k is a variable for representing the vehicle movement distance LV at each sampling time.
LV (k + 1) = LV (k) + ST · Vh (k) (1)
Next, the process proceeds to step S4, where the travel path information is read from the navigation system 2 and the speed limit Vlim of the travel path on which the vehicle is traveling is specified.

Next, it transfers to step S5 and a driving | running | working target value is calculated. Specifically, based on the speed limit Vlim of the travel road identified in step S4, the target vehicle speed Vrs when the host vehicle passes the road surface state detection section, and the road surface state detection section start point from the current position of the host vehicle. The target deceleration rate αd up to is calculated.
The target vehicle speed Vrs is calculated based on the following equation (2), for example. Note that Krs in the equation is a coefficient set according to the road surface condition, and is a value smaller than “1”. When the road surface state is “freezing”, Krs = KrsF, when “snow cover”, Krs = KrsS, when “water film”, Krs = KrsW, and “wet”. Is set to Krs = KrsM, and when “dry”, Krs = KrsD. Note that these coefficients are set in advance by a driving experiment or the like, and are set to a smaller value as the road surface state is slippery and set to a larger value as the road surface is less slippery.
Vrs = Vlim · Krs (2)

The deceleration target value αd is a fixed value. The deceleration target value αd is set to, for example, a deceleration that is generally generated when the driver decelerates after receiving information, and is set by, for example, a running experiment.
Next, the process proceeds to step S6, and the timing for providing information is calculated. First, a deceleration distance Lrs necessary for decelerating from the current host vehicle speed Vh to the target vehicle speed Vrs calculated in step S5 at a predetermined deceleration rate αd is calculated based on the following equation (3). In Equation (3), Tres is a reaction time from when the driver receives information until it reacts.
Lrs = [(Vh ² −Vrs ² ) / (2 · αd)] + (Vh · Tres) (3)

When the deceleration distance Lrs is calculated in this way, the next point for providing road surface information is calculated.
Here, as shown in FIG. 4, when the host vehicle receives the infrastructure information from the radio wave beacon P1, the point where the information provision starts is P2, and the start point of the road surface condition detection section is P3. If the distance from the point P1 where the infrastructure information is received from the radio beacon 13 to the start point P3 of the road surface condition detection section is Lbr, the point P1 where the infrastructure information is received from the radio beacon 13 to the point P2 where the provision of information starts The information provision start point Lrsb representing the distance can be expressed by the following equation (4) based on the deceleration distance Lrs.
Lrsb = Lbr−Lrs (4)

  Therefore, in the process of step S7, the own vehicle movement distance LV with the travel position P1 of the own vehicle at the time of receiving the infrastructure information from the radio wave beacon 13 starting measurement in the process of step S3 as the distance origin is the information. Information on the road surface condition is provided to the driver at the time of reaching the provision start point Lrsb, that is, when the point P2 is reached. That is, image display and voice guidance for notifying that the road surface state is, for example, “snow” is performed using the display 4 and the speaker 5. Then, the process ends.

Next, the operation of the first embodiment will be described.
In the infrastructure system 200 arranged on the road side shown in FIG. 2, the road surface sensor 11 detects the road surface state of the road surface state detection section, and the data processing device 12 is based on the detection information of the road surface sensor 11. Road surface conditions such as “dry” and “snow cover” are estimated and transmitted by the radio beacon 13.
If the vehicle M receives the infrastructure information from the radio beacon 13 and this is road information indicating the road surface state, the vehicle M moves from step S1 to step S3 in FIG. The measurement of the own vehicle movement distance LV from the reception point P1 is started.
Then, the speed limit Vlim of the host vehicle travel path is read as the travel path information from the navigation system 2 as the travel path information. Based on the speed limit Vlim and the road surface state included in the road information notified as the infrastructure information, Based on the equation (2), the target vehicle speed Vrs is calculated.

For example, the target vehicle speed Vrs is set to a larger value as the speed limit Vlim is larger, and conversely, the target vehicle speed Vrs is set to a smaller value as the speed limit Vlim is smaller. If notified as “freezing” as the road surface state, the target vehicle speed Vrs is set to a relatively small value, and if notified as “dry”, the target vehicle speed Vrs is set to a relatively large value.
Therefore, for example, when the host vehicle is currently traveling on an expressway, the target vehicle speed Vrs corresponding to the speed limit Vlim when traveling on the expressway is calculated, and based on this and the actual host vehicle speed Vh. The deceleration distance Lrs is set, and the information provision start point Lrsb is set based on the deceleration distance Lrs. On the contrary, when the host vehicle is traveling on a general road, the target vehicle speed Vrs corresponding to the speed limit Vlim when traveling on the general road is calculated, and based on this and the actual host vehicle speed Vh. The deceleration distance Lrs is set, and the information provision start point Lrsb is set based on the deceleration distance Lrs.

  Here, since the target vehicle speed Vrs is set to a value corresponding to the speed limit Vlim on the travel path of the host vehicle, the host vehicle is traveling at a relatively high speed according to the speed limit Vlim on the travel path. Therefore, the target vehicle speed Vrs is also set to a relatively large value, and the deceleration distance Lrs is set according to the difference between the own vehicle speed Vh and the target vehicle speed Vrs based on the target vehicle speed Vrs set in this way. Will be set. Conversely, when the host vehicle is traveling at a relatively low speed according to the speed limit Vlim of the travel path, the target vehicle speed Vrs is also set to a relatively small value, and thus set. Based on the target vehicle speed Vrs, the deceleration distance Lrs is set according to the difference between the host vehicle speed Vh and the target vehicle speed Vrs.

  Here, when the target vehicle speed Vrs is a fixed value, as described above, when the vehicle is traveling at a relatively high speed, the difference between the host vehicle speed Vh and the target vehicle speed Vrs becomes large, and the deceleration distance Lrs is compared. Information provision timing may be too early. Conversely, when the vehicle is traveling at a relatively low speed, the difference between the host vehicle speed Vh and the target vehicle speed Vrs becomes small, and the deceleration distance Lrs becomes relatively small, so that the information provision timing may be too late.

  However, as described above, since the target vehicle speed Vrs is changed in proportion to the speed limit Vlim of the travel path on which the host vehicle is traveling, the deceleration distance Lrs is set according to the speed limit Vlim. That is, the deceleration distance Lrs can be set according to the traveling speed state of the host vehicle. Therefore, by appropriately setting the correction coefficient Krs, it is possible to set the information provision timing according to the traveling speed state of the host vehicle, that is, without being too early or too late depending on the traveling speed state. Information can be provided at an appropriate timing.

  At this time, the correction coefficient Krs is changed according to the road surface condition. Since the target vehicle speed Vrs is set to be smaller as the road surface state is more slippery, the road surface state is “frozen” even when traveling on the same speed limit road, for example. In this case, since the target vehicle speed Vrs is set to a relatively small value, the deceleration distance Lrs is set longer and information is provided at an earlier timing, and the driver receives the information. The vehicle speed can be reduced sufficiently until the “freezing” point is reached. Conversely, when the road surface state is “dry”, the target vehicle speed Vrs is set to a relatively large value, so the deceleration distance Lrs is set shorter and information is provided at a later timing. Therefore, the deceleration operation time from when the information is provided until the “drying” point is reached is not too long, and the information is provided at an appropriate timing.

In this manner, the target vehicle speed Vrs is set to a smaller value and the information is provided at an earlier timing as the road surface condition is more slippery, so that the vehicle speed can be sufficiently reduced to the vehicle speed according to the road surface condition.
In the first embodiment, the case where the speed limit information of the traveling path of the host vehicle is obtained from the navigation system 2 has been described. However, the present invention is not limited to this. When the infrastructure system 200 is configured to transmit, the speed limit information may be obtained from the infrastructure system 200. In this case, the navigation system 2 is not necessarily provided.

Next, a second embodiment of the present invention will be described.
The second embodiment is the same as the information providing process of the first embodiment except that the calculation process procedure of the travel target value is different. The detailed explanation is omitted.
In the information providing process in the second embodiment, as shown in FIG. 5, as in the first embodiment, infrastructure information is first received from the radio beacon 13 in step S1, and this is road surface information. If there is, the process proceeds from step S2 to step S3, and measurement of the own vehicle movement distance LV is started. Next, the process proceeds to step S4, and if the road information is included in the infrastructure information, the process proceeds to step S5a to calculate the travel target value.

In the second embodiment, the travel target value is calculated according to the following procedure.
Specifically, the target speed Vrs when the host vehicle passes through the road surface condition detection section is set based on the speed limit Vlim notified as the travel path information from the navigation system 2. Note that the target deceleration rate αd from the current position to the start point of the road surface condition detection section is set to a fixed value αd as in the first embodiment.

  Here, the road speed limit Vlim is generally determined by the design speed, road shape, and pedestrian safety requirements. The lower the speed limit, the narrower the road width, the curved road, and the field of view. It is bad or there are many pedestrians such as school zones. Therefore, the coefficient Krs corresponding to the road surface condition in the equation (2) is corrected according to the speed limit Vlim, and the target vehicle speed Vrs is calculated using the corrected coefficient Krsh, so that the target vehicle speed Vrs becomes the speed limit Vlim. Make finer adjustments accordingly.

Specifically, first, the correction coefficient Kh is set based on the following equation (5). In addition, m in Formula (5) is a constant. Here, the correction coefficient Kh is set by calculation. However, for example, a table map showing the correspondence between the speed limit Vlim and the correction coefficient Kh is set in advance, and the speed limit is referred to this table map. A correction coefficient Kh corresponding to Vlim may be set.
Kh = Vlim · m (5)

Next, the coefficient Krs set according to the road surface condition used in the equation (2) is corrected by the correction coefficient Kh according to the following equation (6).
Krsh = Krs · Kh (6)
Then, the target vehicle speed Vrs is calculated based on the following equation (7) using the corrected coefficient Krsh.
Vrs = Vlim · Krsh (7)
Thereafter, based on the target vehicle speed Vrs and the target deceleration rate αd set in this way, the deceleration distance Lrs is calculated from the equation (3) in the same manner as in the first embodiment. The information provision start point Lrsb is calculated from the equation (4), and information is provided when the host vehicle reaches the information provision start point Lrsb (step S7).

Therefore, in the second embodiment, the coefficient Krs set according to the road surface condition is further corrected according to the speed limit Vlim, so that the target vehicle speed Vrs is changed in proportion to the speed limit Vlim. In addition, the change amount of the target vehicle speed Vrs with respect to the change in the limit speed Vlim can be changed according to the limit speed Vlim, and the target vehicle speed Vrs can be set more finely.
Accordingly, the coefficient Krs set according to the road surface condition is corrected according to the speed limit Vlim, and the coefficient Krs is corrected so as to be smaller as the speed limit Vlim is smaller. The target vehicle speed Vrs can be set in consideration of the design speed, road alignment, pedestrian safety, and the like, and information can be provided at an appropriate timing more suitable for the driving environment.

Next, a third embodiment of the present invention will be described.
In the third embodiment, the navigation system 2 of the in-vehicle information providing apparatus 100 detects the position of the own vehicle by GPS as in the first embodiment, and the detected position of the own vehicle and the detected vehicle position are mounted in advance. Based on the map information, the speed limit of the traveling road of the host vehicle is detected and the road surface gradient is detected, and these are output to the information providing controller 3 as traveling road information. The information providing controller 3 provides information in consideration of the speed limit and the road surface gradient.

In addition, the same code | symbol is provided to the same part as the said 1st Embodiment, and the detailed description is abbreviate | omitted.
FIG. 6 is a flowchart illustrating an example of a processing procedure of information providing processing according to the third embodiment.
In the information providing process in the third embodiment, as in the first embodiment, if infrastructure information is received from the radio wave beacon 13, the process proceeds from step S1 to step S2, and this includes road surface information. If so, the process proceeds to step S3 and measurement of the own vehicle movement distance LV is started.
Then, the process proceeds to step S4a, and the speed limit Vlim of the road on which the vehicle is traveling and the road surface gradient Grd [%] up to the road surface condition detection section are read from the navigation system 2 as travel road information.

Next, the process proceeds to step S5b. Based on the speed limit Vlim from the navigation system 2 and the road surface gradient Grd, the target speed Vrs when the host vehicle passes the road surface state detection section and the road surface state detection section start from the current position. The target deceleration rate αd to the point is calculated.
First, the target speed Vrs is calculated from the speed limit Vlim and the coefficient Krs set according to the road surface condition based on the equation (1), as in the first embodiment.
On the other hand, the target deceleration rate αd is calculated by the following procedure.
Here, the acceleration αdc of the host vehicle generated by the road surface gradient Grd [%] can be expressed by the following equation (8).
αdc = g · sin {tan ⁻¹ (Grd / 100)} (8)
Note that g in the equation (8) is a gravitational acceleration, and the road surface gradient Grd [%] is a positive value when it is an ascending slope and a negative value when it is a descending slope.

Then, the target deceleration rate αd is calculated based on the following equation (9) using the acceleration αdc of the host vehicle generated by the road surface gradient thus calculated. In addition, αdf in the equation (9) is a target deceleration when the road surface gradient is “0 [%]”, and is, for example, a deceleration when the driver generally performs a deceleration operation after receiving information. Thus, it is detected by an experiment or the like and set as a fixed value.
αd = αdf + αdc (9)
Then, the process proceeds to step S6, and thereafter, in the same manner as in the first embodiment, the deceleration distance Lrs and the information provision start point Lrsb are calculated based on the equations (3) and (4). Information is provided when the information provision start point Lrsb is reached (step S7).

Therefore, in the third embodiment, similarly to the first embodiment, the target vehicle speed Vrs is set according to the speed limit Vlim and the road surface condition, and the deceleration distance Lrs is set according to the target vehicle speed Vrs. At this time, the deceleration αd is set in consideration of the road surface gradient of the traveling path of the host vehicle.
Therefore, when the traveling road of the own vehicle has an uphill gradient, the acceleration αdc of the own vehicle becomes a positive value and is corrected to a value larger than the deceleration αdf when the road surface gradient is 0%. Therefore, the deceleration distance Lrs calculated based on the corrected target deceleration rate αd becomes a smaller value, and information is provided at a point closer to the change point of the road surface condition.

Here, in the case of an ascending slope, the host vehicle tends to decelerate regardless of the driver's decelerating operation. Therefore, when the decelerating operation is performed after receiving information, the vehicle tends to decelerate too much. However, in the case of climbing slope, since information is provided at a point closer to the change point of the road surface condition, even if the driver tends to decelerate too much, the deceleration period will be shortened accordingly, The vehicle speed will not decrease too much.
On the contrary, when the traveling road of the own vehicle has a downward slope, the acceleration αdc of the own vehicle becomes a negative value and is corrected to a value smaller than the deceleration αdf when the road surface gradient is 0%. . Therefore, the deceleration distance Lrs calculated based on the corrected target deceleration rate αd becomes a larger value, and information is provided at a point further away from the change point of the road surface condition.

  Here, in the case of a downward slope, the host vehicle tends to accelerate due to the downward slope, so even if the driver performs a deceleration operation, the deceleration tends to be insufficient. However, in the case of a downward slope, information is provided at a point farther away from the changing point of the road surface condition, so that the driver's deceleration operation tends to be insufficient, so that the deceleration is performed for a longer period. Thus, the deceleration of the host vehicle is not insufficient when the vehicle decelerates and the vehicle passes through the change point of the road surface condition.

In this way, since the deceleration distance Lrs is set in consideration of the change in the actual deceleration of the host vehicle due to the road surface gradient, even if the road has a road surface gradient, the change in the road surface state The vehicle speed can be sufficiently decelerated to the target vehicle speed before the point is reached, and an accurate deceleration period can be secured, so that information can be provided at the correct timing, and the driver can provide information I do n’t feel uncomfortable.
In the third embodiment, the case where the deceleration αd is set in consideration of the road surface gradient in the first embodiment has been described. However, the present invention is not limited to this. It is also possible to apply to the second embodiment.

  Further, in each of the above-described embodiments, the speed limit Vlim of the travel path and the road surface gradient Grd [%] of the travel path are acquired as the travel path information, and the target vehicle speed Vrs and the deceleration αd are corrected based on these. However, the present invention is not limited to this. For example, when it is possible to know the presence or absence of intersections, junctions, branch points, and toll booths, that is, when the information can be obtained as infrastructure information from the navigation system 2 or the infrastructure system 200, correction is performed according to these information. You may do it.

For example, when a right or left turn is known at an intersection in advance by route guidance or the like, in consideration of the presence of a pedestrian or the like, in the above equation (2), the speed limit Vlim is set to an extremely low speed that can be stopped at any time. Then, the target vehicle speed Vrs may be calculated from the equation (2).
Similarly, at a toll booth, for example, in the case of a vehicle equipped with an automatic toll collection system, the speed limit Vlim is set to a general recommended value (for example, about 20 km / h), and In the case of a vehicle not equipped with an automatic toll collection system, the speed limit may be set to Vlim = 0, and the target vehicle speed Vrs may be calculated based on this.

  Also, at points where traffic congestion is likely to occur, such as branching points and junctions, the traffic speed information provided by a known road traffic information service is referred to, and the speed limit Vlim is set to a lower speed according to the level of traffic congestion. The target vehicle speed Vrs may be calculated based on this correction. Further, when the average vehicle speed at the branch point or the junction point can be obtained by the infrastructure system, the target vehicle speed Vrs calculated by the equation (2) and the speed limit Vlim in the equation (2) are set as the infrastructure system. The target vehicle speed Vrs may be set to a smaller one of the target vehicle speed Vrs when the average vehicle speed at the branch point or the junction point acquired by the above is used.

By doing in this way, it is possible to obtain an effect that it is possible to provide information that more closely matches the traveling speed of vehicles around the host vehicle, road topography, and the like.
Further, in each of the above embodiments, the case where the road surface state is provided is described. However, the present invention is not limited to this. For example, the travel environment information such as the presence of an obstacle in front of the host vehicle and the congestion state is displayed. The present invention can be applied even when the driver is notified in advance.

  In the above embodiment, the road surface condition detection section corresponds to the information provision target section, the in-vehicle wireless device 1 in FIG. 1 corresponds to the information acquisition means, the vehicle speed detection means 2a corresponds to the own vehicle speed detection means, and navigation. The system 2 corresponds to the travel path information detection means, the travel target value calculation unit 3a and the processes of steps S4 or S4a, S5 or S5a or S5b correspond to the travel target value calculation means, and the information provision timing calculation unit 3b and step S3. , S6 corresponds to the timing calculation means, and step S7 corresponds to the information providing means.

It is a schematic block diagram which shows an example of the vehicle-mounted information provision apparatus 100 in this invention. 1 is a schematic configuration diagram of a road-side infrastructure system 200. FIG. 5 is a flowchart illustrating an example of a processing procedure of information providing processing executed by the information providing controller 3 of the in-vehicle information providing apparatus 100. It is explanatory drawing with which it uses for operation | movement description of this invention. It is a flowchart which shows an example of the process sequence of the information provision process in 2nd Embodiment. It is a flowchart which shows an example of the process sequence of the information provision process in 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 In-vehicle wireless device 2 Navigation system 2a Vehicle speed detection means 3 Information providing controller 4 Display 5 Speaker 11 Road surface sensor 12 Data processing device 13 Radio wave beacon 100 In-vehicle information providing device 200 Infrastructure system

Claims (6)

In an in-vehicle information providing apparatus for driving support that has information obtaining means for obtaining in advance information related to the traveling environment of the information provision target section ahead of the host vehicle, and that notifies the occupant of the traveling environment information obtained by the information obtaining means. ,
Own vehicle speed detecting means for detecting the traveling speed of the own vehicle;
Traveling road information detecting means for detecting speed limit information of the traveling road of the host vehicle;
Travel target value calculation means for calculating a travel state target value of the host vehicle based on the travel environment information acquired by the information acquisition means and the speed limit information detected by the travel path information detection means;
Timing calculation means for calculating the information provision timing of the travel environment information based on the host vehicle speed detected by the host vehicle speed detection means and the travel state target value calculated by the travel target value calculation means;
An in-vehicle information providing apparatus for driving support, comprising: information providing means for providing the traveling environment information to an occupant at an information providing timing calculated by the timing calculating means.   2. The on-board information providing apparatus for driving support according to claim 1, wherein the travel target value calculating means calculates a target vehicle speed of the host vehicle when passing through the information provision target section.   The travel target value calculating means is configured to calculate the target vehicle speed by correcting a speed limit specified by the speed limit information with a correction coefficient set according to the travel environment information. The in-vehicle information providing apparatus for driving support according to claim 2. The traveling environment information is information representing a road surface state of the traveling road,
4. The in-vehicle information providing apparatus for driving support according to claim 3, wherein the correction coefficient is set so that the target vehicle speed becomes a smaller value as the road surface state becomes slippery.   The in-vehicle information providing apparatus for driving support according to claim 3 or 4, wherein the correction coefficient is corrected according to the speed limit information. The travel path information detecting means detects slope information of the travel path of the host vehicle along with the speed limit information.
The travel target value calculation means calculates a target deceleration until the host vehicle reaches the information provision target section based on the gradient information detected by the travel path information detection means,
The travel target value calculation means calculates the target deceleration by correcting the target deceleration on a preset flat road in a larger direction when the traveling path of the host vehicle has an ascending slope, 6. The travel according to claim 1, wherein the target deceleration is calculated by correcting the target deceleration on the flat road in a smaller direction. In-vehicle information providing device for support.

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