JP2006111170A - Adaptive cruise control apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent frequent changeover of car-following driving modes. <P>SOLUTION: In an adaptive cruise control apparatus for driving a car to follow a preceding car, in which the entire car speed range for controlling the car-following driving are classified into a plurality of car speed modes, a different car-following driving mode is provided for each car speed range, and a certain distance to the preceding car is maintained while the car-following driving mode is changed according to the self-car speed, when traffic congestion information of the driving road is detected in regard to the driving lane of the self-car, a car speed range in any of the plurality of car-following driving modes is expanded. Or, in case there is a shorter mean changeover period of time, which is a mean value of the changeover intervals when the car-following driving modes are changed over for a plurality of times, than a preset threshold, the car speed range in any of the plurality of car-following driving modes is expanded. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a preceding vehicle follow-up travel control device that follows a preceding vehicle while maintaining a preset inter-vehicle distance.

  There is known a preceding vehicle follow-up travel control device that divides the entire vehicle speed region of 0 to 100 km / h for performing follow-up vehicle follow-up control into a plurality of vehicle speed regions and follows the preceding vehicle in different follow-up running modes in each vehicle speed region. (For example, refer to Patent Document 1).

Prior art documents related to the invention of this application include the following.
JP 2002-234358 A

  However, in the conventional preceding vehicle follow-up travel control device described above, the follow-up travel mode is switched according to the vehicle speed. Therefore, if the vehicle speed fluctuates near the boundary of the vehicle speed region (near the vehicle speed at which the follow-up travel mode is switched), Depending on the situation, there is a problem that the follow-up running mode is frequently switched even if it is not necessary to switch.

  When the traffic congestion information on the travel road is detected, the vehicle speed region in any one of the plurality of following travel modes is expanded. Alternatively, when the average switching time in the follow-up running mode is shorter than a preset threshold value, one of the plurality of vehicle speed regions is expanded.

  According to the present invention, frequent switching of the follow-up running mode is prevented, and troublesomeness can be eliminated.

  The invention of the present application is divided into two vehicle speed areas, a low speed area and a high speed area, for performing the preceding vehicle following traveling control, and the following driving mode in the low speed area (hereinafter referred to as the low speed following traveling mode) and the high speed area. One embodiment applied to a preceding vehicle following traveling control device that has a following traveling mode (hereinafter, referred to as a high speed following traveling mode) and travels following the preceding vehicle in the entire vehicle speed range will be described. The “all vehicle speed range” is a range from the lowest vehicle speed to the highest vehicle speed at which follow-up control is performed. The lowest vehicle speed is an extremely low speed such as 0 km / h or 10 km / h, and the highest vehicle speed is 100 km / h. This is the legal speed or higher.

  The low-speed follow-up travel mode ranges from the lowest vehicle speed of the preceding vehicle follow-up run control (in this embodiment, for example, 10 km / h) to the upper limit vehicle speed in the low-speed follow-up running mode (in this embodiment, 40 km / h). In this mode, the vehicle follows the preceding vehicle while maintaining a preset inter-vehicle distance when there is a preceding vehicle, and cancels the following traveling control when there is no preceding vehicle. On the other hand, the high-speed follow-up running mode is also called ACC (Adaptiv Cruise Control) mode, and the maximum upper-limit vehicle speed of the preceding vehicle follow-up running control (from this lower limit vehicle speed of 35 km / h in this embodiment) (this In a high speed range up to 110 km / h in one embodiment, when there is a preceding vehicle, the vehicle follows the preceding vehicle while maintaining a preset inter-vehicle distance, and when there is no preceding vehicle, a preset vehicle speed In this mode, the vehicle travels at a constant speed (hereinafter referred to as a set vehicle speed).

The set vehicle speed can be arbitrarily set by the driver within the range from the lower limit vehicle speed (35 km / h) in the high-speed following traveling mode to the maximum upper limit vehicle speed (110 km / h) in the preceding vehicle following traveling control. Further, in this embodiment, the upper limit vehicle speed in the low-speed follow-up running mode is set to 40 km / h, the lower limit vehicle speed in the high-speed follow-up running mode is set to 35 km / h, In this example, the low speed area is set to 10 to 40 km / h, the high speed area is set to 40 to 110 km / h, and the high speed area and the low speed area are not overlapped. Good.
In addition, the control system in the low-speed tracking mode is shared with the high-speed tracking mode, but in the low-speed tracking mode, when approaching to a preceding vehicle or an obstacle or interruption of other vehicles, compared to the high-speed tracking mode. The parameters are changed so that the responsiveness when decelerating becomes high. By setting such parameters unique to the low-speed following traveling mode, it is possible to make the setting close to a human driving operation of decelerating early at a low speed.
Furthermore, when the driver performs an accelerator operation while traveling at the upper limit vehicle speed (40 km / h) in the low-speed following traveling mode, the vehicle speed is 40 km / h or higher, but a predetermined vehicle speed (for example, 45 km / h) or higher. The low-speed follow-up running mode is canceled. Further, when the vehicle is traveling at the upper limit vehicle speed (40 km / h) in the low-speed following traveling mode, the resume / accelerate switch 4 may be pushed when the mode is shifted to the high-speed following traveling mode. At this time, if the resume / accelerate switch 4 is pressed once, a bar indicating that the set vehicle speed of the high-speed follow-up running mode can be set is displayed, and if pressed further, 45km / h, 50km / h,・ The set vehicle speed can be increased by 5km / h.

<< First Embodiment of the Invention >>
FIG. 1 is a diagram showing the configuration of the first embodiment. The inter-vehicle distance radar 1 scans a laser beam in front of the vehicle to detect a preceding vehicle, and detects the inter-vehicle distance to the preceding vehicle. In addition, it is good also as a millimeter wave inter-vehicle distance radar using a millimeter wave instead of a laser beam. The vehicle speed sensor 2 detects the traveling speed of the host vehicle. The main switch 3 is an operating member for operating the preceding vehicle follow-up travel control device. When the main switch 3 is turned on, the power is supplied to the preceding vehicle follow-up travel control device and the operation state is entered. The resume / accelerate switch 4 reads the set vehicle speed at the time of the preceding preceding vehicle following traveling control when the preceding vehicle following traveling control is not being performed and resumes the preceding vehicle following traveling control. It is an operating member that increases the set vehicle speed of the high-speed running control. The resume / accelerate switch 4 is also used as a mode switching operation member for switching from the low-speed follow-up running mode to the high-speed follow-up running mode in the vehicle speed overlap region of 35 to 40 km / h.

  The cancel switch 5 is an operation member for canceling the preceding vehicle following traveling control. The set / coast switch 6 is an operation member that starts the preceding vehicle following traveling control when the preceding vehicle following traveling control is not being performed, and reduces the set vehicle speed of the constant speed traveling control when the preceding vehicle following traveling control is being performed. When the preceding / following travel control is started by operating the set / coast switch 6 when the preceding vehicle tracking control is not being performed, the preceding vehicle following traveling control is started if there is a preceding vehicle, and if there is no preceding vehicle, then The constant speed running control is started with the set vehicle speed as the set vehicle speed. The set / coast switch 6 is also used as a mode switching operation member for switching from the high-speed follow-up running mode to the low-speed follow-up running mode in the vehicle speed overlap region of 35 to 40 km / h. The resume / accelerate switch 4, the cancel switch 5, and the set / coast switch 6 are provided in a spoke spoke portion (not shown). The brake switch 7 is a switch that is turned on when a brake pedal (not shown) is depressed.

  The travel control controller 10 includes a CPU 10a, a ROM 10b, a RAM 10c, and the like, and performs the preceding vehicle following travel control and the constant speed travel control described above. The engine control device 11 performs intake air amount control, fuel injection control, ignition timing control, and the like of an engine (not shown) to adjust the output torque and rotation speed of the engine and control the driving force of the vehicle. The transmission control device 12 controls a transmission ratio of an automatic transmission (not shown), that is, a shift position. The brake control device 13 controls the braking force of the vehicle by adjusting the brake fluid pressure. The navigation device 14 detects the current location of the vehicle and provides information such as the legal speed of the traveling road and the type and state of the traveling road (highway, general road, degree of road congestion, presence of intersections and branches, etc.), and the like. The VICS receiver 15 receives traffic jam information by an optical beacon, a radio wave beacon, FM multiplex broadcasting, or the like. The display 16 displays the control state of the preceding vehicle follow-up travel control device and the travel state of the vehicle.

  FIG. 2 is a flowchart showing a vehicle speed region change program according to the first embodiment. The follow-up control controller 10 executes this vehicle speed region change program every 100 msec, for example. In step 1, it is confirmed whether or not the setting of the vehicle speed area remains the initial setting. In this embodiment, the low-speed region 10 to 40 km / h in the low-speed following traveling mode and the high-speed region 35 to 110 km / h in the high-speed following traveling mode are set as initial setting values of the vehicle speed region.

  If the setting of the vehicle speed area remains the initial setting, the process proceeds to step 2 and traffic congestion information relating to the traveling road is obtained from the VICS receiver 15. Here, the traffic jam information of the length L [m] of the traffic jam section is obtained. In the subsequent step 3, it is confirmed whether or not the length L of the traffic jam section ahead of the traveling road is longer than a preset determination threshold Lo.

  If there is a long traffic jam ahead of the road, the vehicle speed will drop as soon as the vehicle enters the traffic jam zone, even if the vehicle speed is in the high speed range and the mode is switched from the low-speed tracking mode to the high-speed tracking mode. The vehicle speed will be in the low speed range, and it will be necessary to switch again from the high speed tracking mode to the low speed tracking mode. Since it is troublesome that such switching of the following driving mode frequently occurs, in this embodiment, when a long traffic jam occurs in front of the driving road, the low speed region is expanded and the time until the traffic jam section is entered. The vehicle travels in the low-speed tracking mode and prevents frequent switching of the tracking mode. Note that a value that minimizes the frequency of switching the follow-up mode may be determined by experiment or the like as the determination threshold value Lo for the congestion section length.

When the traffic congestion section length L is longer than the determination threshold value Lo, the process proceeds to step 4, and when the traffic congestion section length L is equal to or less than the determination threshold value Lo, the process is terminated. In step 4, information on the traveling road is obtained from the navigation device 14 and it is confirmed whether or not the vehicle is traveling on a one-lane road having no branch road. If there is a branch road, there is a high possibility of avoiding a traffic jam section, so even when switching from the low-speed follow-up running mode to the high-speed follow-up run mode, there is little chance of encountering a traffic jam and returning to the low-speed follow-up running mode. Also, by applying the expansion of the low speed region only to roads with one lane, the low speed tracking mode will not be canceled by changing the lane of the preceding vehicle. Even if you perform the following, cancellation and resetting of the follow-up driving will not be repeated. If the vehicle is traveling on a one-lane road with no branch road, the process proceeds to step 5; otherwise, the process is terminated.
As used herein, “no branch road” may be any road, intersection, or no signal that branches during a predetermined distance ahead of the host vehicle. Further, the route to the destination may be set by the navigation device, and there may be no travel route candidates other than those set during a predetermined distance ahead of the host vehicle. That is, in step 4, it is only necessary to determine that there is a long traffic jam ahead of the traveling direction and it is necessary to pass through the traffic jam.

  In step 5, it is confirmed whether or not the resume / accelerate switch 4 has been switched to the high-speed tracking mode. When the driver desires high-speed tracking, it is not preferable because the switching to the high-speed tracking mode becomes difficult if the low speed region is expanded. If the driver intends to switch to the high-speed tracking mode, the process proceeds to step 6; otherwise, the process ends.

  Next, in step 6, it is confirmed whether the low-speed following traveling is canceled. When the driver's brake pedal operation is detected by the brake switch 7, when the driver cancels the follow-up running by the cancel switch 5, or when the preceding vehicle cannot be detected by the inter-vehicle distance radar 1, the low-speed follow-up running Is canceled, so there is no need to expand the low speed region. If the low-speed following traveling has not been canceled, the process proceeds to step 7, and if canceled, the process ends. In step 7, the upper limit vehicle speed in the low speed region is increased to expand the low speed region from the initial set value of 10 to 40 km / h to, for example, 10 to 45 km / h.

  On the other hand, if it is determined in step 1 that the setting of the vehicle speed region remains at the initial setting value, the process proceeds to step 8 to check whether or not the resume / accelerate switch 4 has been switched to the high-speed tracking mode. . As described above, when the driver desires the high-speed following traveling, it is not preferable because the switching to the high-speed following traveling mode becomes difficult if the low speed region is enlarged. Therefore, if the driver is willing to switch to the high-speed follow-up running mode, the process proceeds to step 10 to return the widened low speed range of 10 to 45 km / h to the initial set value of 10 to 40 km / h.

  If the driver does not intend to switch to the high-speed follow-up running mode, the process proceeds to step 9 to confirm cancellation of the low-speed follow-up running. As described above, when the brake pedal operation of the driver is detected by the brake switch 7, when the driver cancels the follow-up driving by the cancel switch 5, or when the preceding vehicle cannot be detected by the inter-vehicle distance radar 1. Since the low-speed following traveling is canceled, it is not necessary to expand the low-speed region. When the low-speed following traveling is canceled, the process proceeds to step 10 and the widened low-speed area 10 to 45 km / h is returned to the initial set value 10 to 40 km / h. On the other hand, if the low-speed following traveling has not been canceled, the process is terminated.

  As described above, according to the first embodiment, when the traffic congestion section is long, the upper limit vehicle speed in the low speed region is increased to expand the low speed region, so that frequent switching of the follow-up travel mode is prevented, which is bothersome. Can be eliminated.

<< Second Embodiment of the Invention >>
In the first embodiment described above, an example in which the low speed region is expanded according to the traffic jam ahead of the traveling road has been shown. However, the low speed region is expanded according to the frequency of switching between the low speed tracking mode and the high speed tracking mode. A second embodiment will be described.
The configuration of the second embodiment is the same as the configuration shown in FIG.

  FIG. 3 is a flowchart showing a vehicle speed region changing program according to the second embodiment. The follow-up control controller 10 executes this vehicle speed region change program every 100 msec, for example. In step 1, it is confirmed whether or not the setting of the vehicle speed area remains the initial setting. In this embodiment, the low-speed region 10 to 40 km / h in the low-speed following traveling mode and the high-speed region 35 to 110 km / h in the high-speed following traveling mode are set as initial setting values of the vehicle speed region.

  If the setting of the vehicle speed area remains the initial setting, the process proceeds to step 22, and the switching when the switching of the following traveling mode has been performed a plurality of times in the past in order to examine the switching frequency between the low speed following traveling mode and the high speed following traveling mode. An average mode switching time T that is an average value of the intervals is calculated. In this embodiment, the switching time is stored in the RAM 10c every time the follow-up running mode is switched. Then, for example, an average mode switching time T for the past 30 minutes is calculated based on the mode switching time data. Next, the routine proceeds to step 23 where it is confirmed whether or not the average mode switching time T is shorter than a preset determination threshold value T1.

  The determination threshold value T1 is set to an appropriate time during which it is determined that the following traveling mode is frequently switched. When the average switching time T in the follow-up running mode is shorter than the determination threshold value T1, the follow-up running mode is frequently switched. Even when the low-speed follow-up running mode is switched to the high-speed follow-up running mode, the vehicle speed immediately decreases. Therefore, switching from the high-speed tracking driving mode to the low-speed tracking driving mode causes frequent switching of the tracking driving mode. Therefore, when the follow-up running mode is frequently switched, frequent switching of the follow-up running mode is prevented by expanding the low speed region. If the average mode switching time T for the past 30 minutes in the follow-up running mode is shorter than the determination threshold value T1, the process proceeds to step 24. If the average switching time T is equal to or greater than the determination threshold value T1, the process is terminated.

  In step 24, information on the traveling road is obtained from the navigation device 14, and it is confirmed whether or not the vehicle is traveling on a one-lane road having no branch road. If there is a branch road, there is a high possibility of avoiding a traffic jam section, so even when switching from the low-speed follow-up running mode to the high-speed follow-up run mode, there is little chance of encountering a traffic jam and returning to the low-speed follow-up running mode. Also, by applying the expansion of the low speed region only to roads with one lane, the low speed tracking mode will not be canceled by changing the lane of the preceding vehicle. Even if you perform the following, cancellation and resetting of the follow-up driving will not be repeated. If the vehicle is traveling on a one-lane road without a branch road, the process proceeds to step 25; otherwise, the process is terminated.

  In step 25, it is confirmed whether or not the resume / accelerate switch 4 has been switched to the high-speed following traveling mode. When the driver desires high-speed tracking, it is not preferable because the switching to the high-speed tracking mode becomes difficult if the low speed region is expanded. If the driver is willing to switch to the high-speed tracking mode, the process proceeds to step 26, and if not, the process is terminated.

  Next, at step 26, it is confirmed whether or not the low-speed following traveling is canceled. When the driver's brake pedal operation is detected by the brake switch 7, when the driver cancels the follow-up running by the cancel switch 5, or when the preceding vehicle cannot be detected by the inter-vehicle distance radar 1, the low-speed follow-up running Is canceled, so there is no need to expand the low speed region. If the low-speed following traveling has not been canceled, the process proceeds to step 27, and if canceled, the process ends. In step 27, the upper limit vehicle speed in the low speed region is increased to expand the low speed region from the initial set value of 10 to 40 km / h to, for example, 10 to 45 km / h.

  On the other hand, if it is determined in step 21 that the setting of the vehicle speed region remains at the initial setting value, the process proceeds to step 28 to check whether or not the resuming / accelerate switch 4 has switched to the high-speed follow-up travel mode. . As described above, when the driver desires the high-speed following traveling, it is not preferable because the switching to the high-speed following traveling mode becomes difficult if the low speed region is enlarged. Accordingly, if the driver intends to switch to the high-speed following running mode, the process proceeds to step 31 to return the widened low speed range of 10 to 45 km / h to the initial set value of 10 to 40 km / h.

  If the driver does not intend to switch to the high-speed follow-up running mode, the process proceeds to step 29 to confirm cancellation of the low-speed follow-up running. As described above, when the brake pedal operation of the driver is detected by the brake switch 7, when the driver cancels the follow-up driving by the cancel switch 5, or when the preceding vehicle cannot be detected by the inter-vehicle distance radar 1. Since the low-speed following traveling is canceled, it is not necessary to expand the low-speed region. When the low-speed following traveling is canceled, the process proceeds to step 31, and the widened low-speed area 10 to 45 km / h is returned to the initial set value 10 to 40 km / h.

  If the low-speed following traveling has not been canceled, the process proceeds to step 30 to check whether the average mode switching time T is longer than a preset determination threshold value T2. The determination threshold value T2 is set to an appropriate time during which it is determined that the following traveling mode is not frequently switched. When the average switching time T in the follow-up running mode is longer than the determination threshold value T2, the process proceeds to step 31, and the widened low speed region 10 to 45 km / h is returned to the initial set value 10 to 40 km / h. On the other hand, when the average mode switching time T is equal to or shorter than the determination threshold value T2, the process is terminated.

  As described above, according to the second embodiment, when the follow-up driving mode is frequently switched, the low-speed region of the low-speed following running mode is expanded, so that frequent switching of the following running mode is prevented and bothered. Can be eliminated.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the inter-vehicle distance radar 1 is the inter-vehicle distance detecting means, the vehicle speed sensor 2 is the vehicle speed detecting means, the follow-up controller 10 is the follow-up running control means and the area switching means, the VICS receiver 15 is the congestion information detecting means, and the resume / The acceleration switch 4 and the set / coast switch 6 constitute operation members. In addition, as long as the characteristic function of this invention is not impaired, each component is not limited to the said structure.

In the above-described embodiment, the example in which the upper limit vehicle speed in the low speed region corresponding to the low speed tracking mode is increased and the low speed region is expanded is shown. However, the lower limit vehicle speed in the high speed region corresponding to the high speed tracking mode is decreased. The high speed region may be enlarged. In a traffic jam on an expressway, there is a case where the vehicle runs slowly while following a preceding vehicle at a medium speed of 30 to 50 km / h. Further, even when the switching frequency of the follow-up running mode is high, the time for running in the high-speed follow-up running mode may be longer than the time for running in the low-speed following running mode. In such a case, frequent mode switching can be prevented by lowering the lower limit vehicle speed of the high speed region and expanding the high speed region.
In addition, it may be determined whether to expand the low speed region or the high speed region according to the average vehicle speed of the host vehicle when the traffic jam or the follow-up traveling mode is frequently switched. For example, when the average vehicle speed is a vehicle speed in the high speed region, the high speed region is expanded. Conversely, when the average vehicle speed is a vehicle speed in the low speed region, the low speed region is expanded.

  In the above-described embodiment, an example is shown in which the entire vehicle speed region where the preceding vehicle follow-up running control is performed is divided into two vehicle speed regions, a low speed region and a high speed region, but the present invention is applied even when the vehicle is divided into three or more vehicle speed regions. Can be applied. It should be noted that the upper and lower limit speeds of each vehicle speed region in the above-described embodiment are merely examples, and the present invention is not limited to this.

It is a figure which shows the structure of 1st Embodiment. It is a flowchart which shows the vehicle speed area | region change program of 1st Embodiment. It is a flowchart which shows the vehicle speed area | region change program of 2nd Embodiment. It is a figure which shows the vehicle speed area | region change process of 2nd Embodiment.

Explanation of symbols

1 Inter-vehicle distance radar 2 Vehicle speed sensor 3 Main switch 4 Resume / Accelerate switch 5 Cancel switch 6 Set / coast switch 7 Brake switch 10 Tracking control controller 10a CPU
10b ROM
10c RAM
11 Engine control device 12 Transmission control device 13 Brake control device 14 Navigation device 15 VICS receiver 16 Display

Claims (7)

An inter-vehicle distance detecting means for detecting an inter-vehicle distance from a preceding vehicle;
Vehicle speed detecting means for detecting the own vehicle speed;
Following travel control means for following the preceding vehicle while maintaining a certain inter-vehicle distance;
All vehicle speed areas for performing preceding vehicle following running control are divided into a plurality of vehicle speed areas, each vehicle speed area has a different following running mode, and mode switching means for switching the following running mode according to the own vehicle speed is provided. In the preceding vehicle following travel control device,
Congestion information detection means for detecting traffic congestion information on the road in the driving lane of the host vehicle,
The area switching means expands the vehicle speed area of any one of the plurality of following driving modes when the traffic information on the road is detected by the traffic information detecting means. Control device. In the preceding vehicle following travel control device according to claim 1,
The traffic information detecting means detects whether or not the vehicle is traveling in a traffic jam section,
The preceding vehicle follow-up travel control device, wherein the mode switching means determines a vehicle speed region that expands according to an average vehicle speed of the host vehicle during travel in a traffic jam section. An inter-vehicle distance detecting means for detecting an inter-vehicle distance from a preceding vehicle;
Vehicle speed detecting means for detecting the own vehicle speed;
Following travel control means for following the preceding vehicle while maintaining a certain inter-vehicle distance;
All vehicle speed areas for performing preceding vehicle following running control are divided into a plurality of vehicle speed areas, each vehicle speed area has a different following running mode, and mode switching means for switching the following running mode according to the own vehicle speed is provided. In the preceding vehicle following travel control device,
If the average switching time, which is the average value of the switching intervals when the switching of the following traveling mode is performed a plurality of times, is shorter than a preset threshold value, the mode switching means A preceding vehicle follow-up travel control device characterized in that the vehicle speed range of any of the above is expanded. In the preceding vehicle follow-up travel control device according to claim 3,
The preceding vehicle follow-up travel control device, wherein the mode switching means determines a follow-up travel mode in a vehicle speed region that expands according to an average vehicle speed when an average switch time in the vehicle speed region is shorter than a threshold value. In the preceding vehicle follow-up travel control device according to any one of claims 1 to 4,
The preceding vehicle following travel control device, wherein the mode switching means expands the vehicle speed region only when traveling on a one-lane road without a branch road based on information from the navigation device. In the preceding vehicle following travel control device according to any one of claims 1 to 5,
With an operation member that commands switching of the vehicle speed range,
The preceding vehicle follow-up running control, wherein when the follow-up running mode is switched according to the operation of the operation member, the mode switching means returns the expanded vehicle speed region of the follow-up running mode to the initial vehicle speed region. apparatus. In the preceding vehicle follow-up travel control device according to any one of claims 1 to 6,
The mode switching means is configured to return the expanded vehicle speed region to the initial vehicle speed region when the follow-up traveling control is canceled during the following traveling control in the following traveling mode in which the vehicle speed region is expanded. Car following travel control device.

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