JP2010006334A - Vehicle speed limiting device and vehicle speed limiting method - Google Patents

Abstract

The present invention provides a vehicle speed limiting device for safely accelerating a vehicle exceeding a set limiter speed during ASL control.
An engine ECU that performs acceleration control of the host vehicle according to the inter-vehicle distance when it is detected that the amount of depression of an accelerator pedal has reached a predetermined amount or more during ASL control. This engine ECU accelerates the host vehicle at an acceleration corresponding to the depression amount of the accelerator pedal when the inter-vehicle distance is equal to or greater than a predetermined distance, and more than the acceleration according to the depression amount of the accelerator pedal when the inter-vehicle distance is less than the predetermined distance. Accelerate your vehicle with limited acceleration.
[Selection] Figure 2

Description

  The present invention relates to a vehicle speed limiter that performs ASL (Adjustable Speed Limiter) control, and more particularly, to a vehicle speed limiter that performs ASL control that can accelerate beyond a set limiter speed when detecting the ON of a kickdown switch.

  2. Description of the Related Art Conventionally, there has been a vehicle speed limiting device that performs ASL control (hereinafter referred to as first ASL control) that does not accelerate a host vehicle beyond a set limiter speed set by the driver even when the driver depresses an accelerator pedal. According to the first ASL control, the driver does not inadvertently accelerate the host vehicle exceeding the speed limit by setting the preset limiter speed in advance. Specifically, if the driver sets a limiter speed of 60 km / h when driving on a road with a speed limit of 60 km / h, the speed limit can be set without having to worry about the speedometer. There is no longer any acceleration of the host vehicle exceeding 60 km / h. As a result, the conventional vehicle speed limiting device that performs the first ASL control has improved safety during traveling.

  However, the conventional vehicle speed limiter that performs the first ASL control has a problem when the driver intentionally exceeds the set limiter speed in order to overtake the preceding vehicle or the like. It was. For example, consider a case where the preceding vehicle approaches because the speed of the preceding vehicle is slower than the speed of the host vehicle. In this case, the driver can overtake the preceding vehicle by driving the host vehicle at a speed equal to or lower than the set limiter speed. In addition, the driver can cancel the first ASL control by pressing the cancel switch, and can drive the host vehicle at a speed exceeding the set limiter speed to pass the preceding vehicle.

  Here, from the viewpoint of safety, it is usually preferable for the preceding vehicle to pass quickly. For this reason, when overtaking a preceding vehicle at a speed equal to or lower than the set limiter speed, it is often impossible to quickly overtake the preceding vehicle, resulting in a decrease in safety as a result.

  Further, when the first ASL control is canceled by pushing the cancel switch and the preceding vehicle is overtaken at a speed exceeding the set limiter speed, the driver needs to perform an operation of pushing the cancel switch. In general, a steering wheel, an accelerator pedal, and a brake pedal are always operated by the driver during driving. For this reason, the driver pushes a cancel switch that is not always operated during overtaking that requires special attention, and as a result, smooth driving is hindered. In particular, when the driver visually looks for and presses the cancel switch, the safety is further reduced.

  As a means for solving the problem of the first ASL control described above, there is a vehicle speed limiting device that performs ASL control (hereinafter referred to as second ASL control) described in Patent Document 1. The second ASL control is basically the same as the first ASL control, but differs from the first ASL control in that the host vehicle can be temporarily accelerated exceeding the set limiter speed. This will be described in detail below.

  In the second ASL control, in principle, even if the driver depresses the accelerator pedal, the host vehicle is not accelerated beyond the set limiter speed. However, in the second ASL control, as an exception, when the driver detects that the accelerator pedal has been depressed to the vicinity of the fully open position by turning on the kick down switch, the host vehicle is accelerated according to the accelerator opening. In other words, in the second ASL control, when the accelerator pedal is depressed to the fully open position, the vehicle exceeds the set limiter speed and accelerates the host vehicle according to the accelerator opening. At this time, since the accelerator opening is near the fully open position, the host vehicle fully accelerates. Thereafter, when the speed of the host vehicle returns to the set limiter speed or less, the second ASL control performs a control that does not accelerate the host vehicle beyond the set limiter speed unless the accelerator pedal is again depressed to the fully open position.

  As described above, according to the conventional vehicle speed limiter that performs the second ASL control, the driver can set the speed limiter speed by simply depressing the accelerator pedal that is always operated to the fully open position. The vehicle can be accelerated beyond this. That is, according to the conventional vehicle speed limiting device that performs the second ASL control, the driver intentionally accelerates the own vehicle exceeding the set limiter speed without the driver performing a special operation of pressing the cancel switch. Can be made. Therefore, according to the conventional vehicle speed limiting device that performs the second ASL control, the host vehicle is usually driven at a speed equal to or lower than the set limiter speed, and the set limiter is temporarily set in response to the clear intention of the driver. The host vehicle can be accelerated beyond the speed, and for example, the preceding vehicle can be quickly overtaken.

In the following description, the second ASL control described above is simply referred to as conventional ASL control. In the following description, the conventional vehicle speed limiting device that performs the second ASL control is simply referred to as a conventional vehicle speed limiting device.
JP-T-2005-511401

  However, the conventional vehicle speed limiting device described above has the following problems. In the conventional vehicle speed limiting device, when the kick-down switch detects that the accelerator pedal is fully depressed (hereinafter, the kick-down switch is turned on), the host vehicle fully accelerates. At this time, when a preceding vehicle exists, there is a possibility that the preceding vehicle is too close. In particular, when the driver does not recognize that the host vehicle is fully accelerated beyond the set limiter speed by turning on the kick-down switch, there is a possibility that the driver may be anxious. Even if the driver recognizes that the host vehicle will fully accelerate beyond the set limiter speed by turning on the kick-down switch, the driver will drive if the distance between the host vehicle and the preceding vehicle is small. The attention of the person is necessary.

  Therefore, an object of the present invention is to provide a vehicle speed limiting device that allows a driver to intentionally exceed the set limiter speed and safely accelerate the host vehicle even when a preceding vehicle is present during ASL control. It is to provide that method.

  The present invention is directed to a vehicle speed limiting device that performs ASL control that limits the speed of the host vehicle to a speed that is lower than a set limiter speed set by a driver. In order to achieve the above object, the vehicle speed limiting device according to the present invention includes an accelerator sensor that detects that the amount of depression of the accelerator pedal exceeds a predetermined amount, and an inter-vehicle distance that measures the inter-vehicle distance between the preceding vehicle and the host vehicle. An engine ECU that performs acceleration control of the host vehicle according to the measured inter-vehicle distance when it is detected that the amount of depression of the accelerator pedal exceeds a predetermined amount during ASL control; If the measured inter-vehicle distance is greater than or equal to the predetermined distance, the vehicle is accelerated at an acceleration corresponding to the accelerator pedal depression amount. If the measured inter-vehicle distance is less than the predetermined distance, the accelerator pedal depression amount is The host vehicle is accelerated at an acceleration that is more limited than the acceleration.

  Thereby, the vehicle speed limiting device of the present invention can perform safe acceleration in consideration of the inter-vehicle distance exceeding the set limiter speed during the ASL control.

  Preferably, when the measured inter-vehicle distance is equal to or greater than a predetermined distance, the inter-vehicle distance is not measured because there is no preceding vehicle within the measurable distance of the inter-vehicle distance sensor.

  Preferably, when the measured inter-vehicle distance is less than a predetermined distance, the engine ECU decelerates the host vehicle at an acceleration corresponding to the surplus inter-vehicle distance calculated by subtracting the predetermined safe inter-vehicle distance from the measured inter-vehicle distance. Accelerate.

  Thereby, the vehicle speed limiting device of the present invention can perform safe acceleration using a predetermined safe inter-vehicle distance as a reference.

  Preferably, the engine ECU calculates a relative speed between the preceding vehicle and the host vehicle using the measured change in the inter-vehicle distance, and determines a predetermined safe inter-vehicle distance according to the calculated relative speed.

  Preferably, the calculated relative speed takes a positive value when the measured inter-vehicle distance increases, takes a negative value when the measured inter-vehicle distance decreases, and is calculated by the engine ECU. The smaller the relative speed value, the larger the predetermined safe inter-vehicle distance.

  Thereby, the vehicle speed limiting device of the present invention can perform safer acceleration.

  Preferably, the engine ECU determines a smaller value as the acceleration corresponding to the calculated surplus inter-vehicle distance as the calculated surplus inter-vehicle distance is smaller.

  Thereby, the vehicle speed limiting device of the present invention can perform safer acceleration.

  Further, the engine ECU may determine 0 as the acceleration value corresponding to the calculated surplus inter-vehicle distance when the calculated surplus inter-vehicle distance value is 0 or less.

  Thereby, the vehicle speed limiting device of the present invention can further reduce the possibility that the host vehicle will collide with the preceding vehicle.

  Preferably, the engine ECU further determines a predetermined safe inter-vehicle distance according to the speed of the host vehicle measured by the speed sensor.

  Preferably, the engine ECU determines a larger value as the predetermined safe inter-vehicle distance as the measured value of the speed of the host vehicle is larger.

  Thereby, the vehicle speed limiting device of the present invention can perform safer acceleration.

  Preferably, the inter-vehicle distance sensor further detects the steering angle of the host vehicle and moves a measurement area for measuring the inter-vehicle distance between the preceding vehicle and the host vehicle according to the detected steering angle.

  As a result, the vehicle speed limiting device of the present invention enables smooth overtaking of the host vehicle and avoids erroneous detection of a preceding vehicle in the adjacent lane even when the host vehicle travels on a curve.

  Preferably, the inter-vehicle distance sensor further detects the rudder angle of the own vehicle, and the engine ECU further calculates the surplus inter-vehicle distance according to the detected rudder angle and the speed of the own vehicle measured by the speed sensor. Correct the acceleration according to the distance.

  Preferably, the engine ECU corrects the acceleration corresponding to the calculated marginal vehicle distance to a smaller value as the detected steering angle is larger, and calculates the larger marginal vehicle distance as the measured speed of the host vehicle is larger. The acceleration corresponding to is corrected to a small value.

  Thereby, the vehicle speed limiting device of the present invention can perform safer acceleration.

  Further, preferably, the engine ECU further determines an acceleration corresponding to the calculated marginal inter-vehicle distance according to the distance value from the own vehicle acquired from the navigation system to the next corner and the speed of the own vehicle measured by the speed sensor. To correct.

  Preferably, the engine ECU corrects the acceleration according to the calculated marginal vehicle distance to a smaller value as the distance value from the acquired own vehicle to the next corner is smaller, and the measured speed of the own vehicle is The larger the value is, the smaller the acceleration corresponding to the calculated marginal vehicle distance is corrected.

  Thereby, the vehicle speed limiting device of the present invention can perform safer acceleration.

  Further, the present invention is also directed to a vehicle speed limiting method for performing ASL control for limiting the speed of the host vehicle below a set limiter speed set by a driver. In order to achieve the above object, the vehicle speed limiting method of the present invention includes a step of detecting that the amount of depression of the accelerator pedal exceeds a predetermined amount, a step of measuring a distance between the preceding vehicle and the host vehicle, And a step of performing acceleration control of the host vehicle according to the measured inter-vehicle distance when it is detected that the amount of depression of the accelerator pedal exceeds a predetermined amount during ASL control. In the performing step, if the measured inter-vehicle distance is equal to or greater than the predetermined distance, the host vehicle is accelerated at an acceleration corresponding to the accelerator pedal depression amount, and if the measured inter-vehicle distance is less than the predetermined distance, the accelerator pedal depression amount is set. The host vehicle is accelerated at a limited acceleration rather than the corresponding acceleration.

  Thereby, the vehicle speed limiting method of the present invention can perform safe acceleration in consideration of the inter-vehicle distance that exceeds the set limiter speed during ASL control.

  As described above, according to the vehicle speed limiting device and the vehicle speed limiting method of the present invention, even when there is a preceding vehicle at the time of ASL control, the driver intentionally exceeds the set limiter speed safely. The host vehicle can be accelerated.

(First embodiment)
FIG. 1 is a block diagram illustrating a configuration example of a vehicle speed limiting device 100 according to the first embodiment. As shown in FIG. 1, the vehicle speed limiting device 100 includes an accelerator sensor 10, an inter-vehicle distance sensor 11, and an engine ECU 12.

  The accelerator sensor 10 detects that the accelerator pedal has been fully depressed and notifies the engine ECU 12 of it. More specifically, the accelerator sensor 10 detects that the accelerator pedal has been depressed to a predetermined depression amount (for example, 90% depression amount) or more and notifies the engine ECU 12 of the depression. The accelerator sensor 10 is, for example, a kick down switch. The kick-down switch is a switch that detects that the accelerator pedal has been greatly depressed in an automobile equipped with an automatic transmission. In general, when the kick down switch is turned on, the vehicle switches to a lower speed gear than the current gear, and the host vehicle accelerates rapidly. In the following description, for convenience of explanation, the accelerator sensor 10 is a kickdown switch, and will be described as notifying the engine ECU 12 of information on the kickdown switch being ON (hereinafter referred to as kickdown ON information).

  The inter-vehicle distance sensor 11 detects a preceding vehicle traveling in front of the host vehicle, measures the inter-vehicle distance between the host vehicle and the preceding vehicle, and notifies the engine ECU 12 of the measured inter-vehicle distance. The inter-vehicle distance sensor 11 is a laser sensor, for example.

  The speed sensor 14 measures the speed of the host vehicle and notifies the engine ECU 12 of the measured speed of the host vehicle. The speed sensor 14 is, for example, a general speedometer.

  The electronic throttle 13 supplies fuel to an engine (not shown) to operate the engine. The electronic throttle 13 may be replaced with an injector or the like.

  The engine ECU 12 controls the electronic throttle 13 based on the kick down ON information notified from the accelerator sensor 10, the inter-vehicle distance notified from the inter-vehicle distance sensor 11, and the own vehicle speed notified from the speed sensor 14. Control the speed of the vehicle. Details will be described later.

  FIG. 2 is a flowchart for explaining the operation of the vehicle speed limiting device 100 according to the first embodiment. Below, with reference to FIG.1 and FIG.2, operation | movement of the vehicle speed limiting apparatus 100 is demonstrated in detail.

  First, in step S101, the accelerator sensor 10 detects whether or not the accelerator pedal has been fully depressed. That is, in step S101, it is determined whether or not the kick down switch is turned on. When the kick down switch is turned on, the process proceeds to step S102. In this case, the accelerator sensor 10 notifies the engine ECU 12 of kickdown ON information. If the kick-down switch is not ON, the process proceeds to step S108 and conventional ASL control is performed. In this case, the host vehicle does not accelerate beyond the set limiter speed preset by the driver. And after the process of step S108, it returns to step S101.

  In step S102, the inter-vehicle distance sensor 11 measures the inter-vehicle distance between the host vehicle and the preceding vehicle. The measured inter-vehicle distance is notified to the engine ECU 12. Here, when the preceding vehicle exists farther than the distance at which the inter-vehicle distance sensor 11 can measure the inter-vehicle distance, or when the preceding vehicle does not exist, the inter-vehicle distance sensor 11 cannot measure the inter-vehicle distance. Further, even when a preceding vehicle exists outside the measurement area where the inter-vehicle distance sensor 11 measures the inter-vehicle distance, the inter-vehicle distance sensor 11 cannot measure the inter-vehicle distance. Thus, when the inter-vehicle distance sensor 11 cannot measure the inter-vehicle distance, the inter-vehicle distance is not notified to the engine ECU 12.

  Next, in step S103, the engine ECU 12 determines whether the inter-vehicle distance between the host vehicle and the preceding vehicle is equal to or greater than the suppression acceleration distance. Here, the suppression acceleration distance is a distance at which control unique to the present invention, which will be described in detail later, is performed, for example, 150 m. If the inter-vehicle distance between the host vehicle and the preceding vehicle is not equal to or greater than the suppression acceleration distance, the process proceeds to step S104. When the inter-vehicle distance between the host vehicle and the preceding vehicle is equal to or greater than the suppression acceleration distance, the process proceeds to step S108 and conventional ASL control is performed. Even when the inter-vehicle distance is not notified to the engine ECU 12 because the inter-vehicle distance sensor 11 cannot measure the inter-vehicle distance described in step S102, the engine ECU 12 determines that the inter-vehicle distance between the host vehicle and the preceding vehicle is equal to or greater than the suppression acceleration distance. Judge that there is. In this case, since the kick-down switch is turned on in step S101, the host vehicle fully accelerates according to the accelerator opening degree near the fully open position in step S108. And after the process of step S108, it returns to step S101.

  Next, in step S104, the engine ECU 12 calculates the relative speed between the host vehicle and the preceding vehicle using the change in the inter-vehicle distance notified from the inter-vehicle distance sensor 11, and determines the safe inter-vehicle distance corresponding to the calculated relative speed. decide. Here, the safe inter-vehicle distance is, for example, an inter-vehicle distance that is predicted that the own vehicle can avoid a collision when the preceding vehicle applies a sudden brake, and is a distance that depends on the braking ability of the own vehicle. . FIG. 3 is a diagram illustrating an example of a correspondence relationship between the relative speed between the host vehicle and the preceding vehicle and the safe inter-vehicle distance. In FIG. 3, the relative speed when the host vehicle leaves the preceding vehicle is represented by a positive value, and the relative speed when the host vehicle approaches the preceding vehicle is represented by a negative value. As shown in FIG. 3, the value of the safe inter-vehicle distance increases as the value of the relative speed decreases. That is, the safe inter-vehicle distance is increased as the possibility that the own vehicle collides with the preceding vehicle increases. In FIG. 3, for convenience of explanation, the relationship between the relative speed and the safe inter-vehicle distance is a linear relationship. However, the relationship between the relative speed and the safe inter-vehicle distance may not be a linear relationship as long as the value of the safe inter-vehicle distance increases as the relative speed value decreases.

  Next, in step S105, the engine ECU 12 calculates a marginal inter-vehicle distance by subtracting the safe inter-vehicle distance from the inter-vehicle distance measured by the inter-vehicle distance sensor 11. That is, the engine ECU 12 calculates the allowance until the inter-vehicle distance between the host vehicle and the preceding vehicle becomes equal to the safe inter-vehicle distance as the extra inter-vehicle distance.

  Next, in step S106, the engine ECU 12 determines a target speed corresponding to the surplus inter-vehicle distance calculated in step S105. Here, the target speed is a target speed reached after α seconds by acceleration. Note that the value of α is preferably set to a relatively small value (0.10, 0.05, etc.). Below, the method in which engine ECU12 determines target speed is demonstrated concretely. FIG. 4 is a diagram illustrating an example of a correspondence relationship between the marginal inter-vehicle distance and the additional speed. Here, the target speed is a speed obtained by adding the current speed and the additional speed. As shown in FIG. 4, when the marginal inter-vehicle distance is a positive value, the value of the additional speed increases as the marginal inter-vehicle distance increases. In FIG. 4, for convenience of explanation, the relationship between the marginal inter-vehicle distance and the additional speed is a linear relationship when the marginal inter-vehicle distance is a positive value. However, the relationship between the surplus inter-vehicle distance and the additional speed may not be a linear relationship as long as the surplus inter-vehicle distance is a positive value and the value of the additional speed increases as the surplus inter-vehicle distance increases. Further, as shown in FIG. 4, the additional speed is 0 when the marginal inter-vehicle distance is 0 or less. First, the engine ECU 12 determines an additional speed corresponding to the surplus inter-vehicle distance based on the relationship shown in FIG. Next, the engine ECU 12 calculates a target speed by adding an additional speed to the host vehicle speed notified from the speed sensor 14. In this way, the engine ECU 12 determines the target speed.

  Next, in step S107, the engine ECU 12 controls the electronic throttle 13 to accelerate the host vehicle for α seconds with an acceleration reaching the target speed after α seconds. If the additional speed is 0 because the marginal inter-vehicle distance is 0 or less (see FIG. 4), the engine ECU 12 does not substantially accelerate the host vehicle. Then, it returns to step S101.

  5 to 8 are diagrams for specifically explaining the operation of the vehicle speed limiting device 100. FIG. Below, with reference to FIGS. 1-8, operation | movement of the vehicle speed limiting apparatus 100 is demonstrated more concretely. In the following description, for convenience of explanation, α seconds described in steps S106 and S107 are assumed to be 5 seconds. In the following description, it is assumed that the set limiter speed is set to 105 km / h, the suppression acceleration distance is 150 m, and the inter-vehicle distance measurable distance of the inter-vehicle distance sensor 11 is 200 m.

  First, as shown in FIG. 5 (a), let us consider a state in which both the host vehicle and the preceding vehicle are traveling in the same lane at 100 km / h and the inter-vehicle distance is 100 m. In this state, consider a case where the driver steps on the accelerator to the vicinity of the fully open position and the accelerator sensor 10 (kick down switch) is turned on (step S101: Yes). In this case, as shown in FIG. 5A, the preceding vehicle is located in the measurement area of the inter-vehicle distance sensor 11, so the inter-vehicle distance sensor 11 measures the inter-vehicle distance 100m between the host vehicle and the preceding vehicle (step S102). ). Next, the engine ECU 12 determines that the inter-vehicle distance 100 m is not greater than the suppression acceleration distance 150 m (step S103: No). Next, the engine ECU 12 calculates a relative speed of 0 km / h between the host vehicle and the preceding vehicle using a change in the inter-vehicle distance, and corresponds to the relative speed of 0 km / h based on the predetermined correspondence described with reference to FIG. A safe inter-vehicle distance of 50 m is determined (step S104). Next, the engine ECU 12 subtracts the safe inter-vehicle distance 50 m from the inter-vehicle distance 100 m to calculate a surplus inter-vehicle distance 50 m (step S105). Next, the engine ECU 12 determines the additional speed 10 km / h corresponding to the surplus inter-vehicle distance 50 m based on the predetermined correspondence described with reference to FIG. 4, and the current host vehicle speed 100 km / h notified from the speed sensor 14. The target speed 110 km / h is calculated by adding the additional speed 10 km / h to (step S106). Next, the engine ECU 12 controls the electronic throttle 13 while referring to the host vehicle speed notified from the speed sensor 14 and accelerates the host vehicle for five seconds at an acceleration that reaches the target speed 110 km / h after five seconds ( Step S107).

  FIG. 5B shows a state in which the acceleration of the host vehicle for 5 seconds in step S107 described with reference to FIG. In this state, the inter-vehicle distance has decreased to 93.1 m, and the host vehicle speed has reached 110 km / h. In the state shown in FIG. 5B, when the accelerator sensor 10 remains ON (step S101: Yes), the inter-vehicle distance 93.1m is measured (step S102), and the inter-vehicle distance 93.1m is the suppression acceleration distance 150m. It is determined that the above is not the case (step S103: No), the relative speed −10 km / h is measured, and a safe inter-vehicle distance 60 m corresponding to the relative speed −10 km / h is determined based on the correspondence relationship in FIG. 3 (step S104). ). Next, the safe inter-vehicle distance of 60 m is subtracted from the inter-vehicle distance of 93.1 m to calculate a surplus inter-vehicle distance of 33.1 m (step S105). Next, an additional speed of 6.6 km / h corresponding to the marginal inter-vehicle distance of 33.1 m is determined based on the correspondence relationship of FIG. 4, and the additional speed of 6.6 km / h is added to the current host vehicle speed of 110 km / h. Thus, the target speed 116.6 km / h is determined (step S106). Next, the host vehicle is accelerated for 5 seconds at an acceleration reaching the target speed of 116.6 km / h after 5 seconds (step S107).

  FIG. 6C shows a state where the acceleration of the host vehicle for 5 seconds in step S107 described with reference to FIG. In this state, the inter-vehicle distance has decreased to 74.6 m, and the host vehicle speed has reached 116.6 km / h. In the state shown in FIG. 6C, when the accelerator sensor 10 remains ON (step S101: Yes), the inter-vehicle distance 74.6m is measured (step S102), and the inter-vehicle distance 74.6m is suppressed to the suppression acceleration distance 150m. It is determined that this is not the case (step S103: No), the relative speed -16.6 km / h is measured, and the safe inter-vehicle distance 66.6 m corresponding to the relative speed -16.6 km / h based on the correspondence relationship of FIG. It is determined (step S104). Next, the safe inter-vehicle distance of 66.6 m is subtracted from the inter-vehicle distance of 74.6 m to calculate a surplus inter-vehicle distance of 8.0 m (step S105). Next, an additional speed of 1.6 km / h corresponding to a marginal inter-vehicle distance of 8.0 m is determined based on the correspondence relationship of FIG. 4, and an additional speed of 1.6 km / h is added to the current host vehicle speed of 116.6 km / h. By adding, target speed 118.2km / h is determined (step S106). Next, the host vehicle is accelerated for 5 seconds at an acceleration reaching the target speed 118.2 km / h after 5 seconds (step S107).

  FIG. 6D shows a state where the acceleration of the host vehicle for 5 seconds in step S107 described with reference to FIG. In this state, the inter-vehicle distance has decreased to 50.4 m, and the host vehicle speed has reached 118.2 km / h.

  The operation of the vehicle speed limiting device 100 when the processing is repeated on the route of steps S101 to S107 in FIG. 2 has been specifically described above with reference to FIGS. That is, when the driver steps on the accelerator pedal to the fully open position and the kick down switch is ON, and the inter-vehicle distance is not more than the suppression acceleration distance of 150 m or more, the vehicle speed limiting device 100 is set to the set limiter speed (105 km / h) Regardless of h), the host vehicle is accelerated according to the target speed calculated every 5 seconds. As described with reference to FIG. 4, when the surplus inter-vehicle distance is 0 or less, the target speed is equal to the own vehicle speed, so the own vehicle is not accelerated and the current speed is maintained.

  Next, the operation of the vehicle speed limiting device 100 when the process is repeated in the routes of steps S101, S102, S103, and S108 in FIG. 2 will be specifically described. That is, a case will be described in which the accelerator pedal is depressed to the fully open position and the kick down switch is ON, and the inter-vehicle distance is greater than or equal to the suppression acceleration distance, or the inter-vehicle distance cannot be measured. In this case, conventional ASL control is performed (step S108), and the host vehicle fully accelerates regardless of the set limiter speed. Hereinafter, the case where the host vehicle overtakes the preceding vehicle will be described as an example with reference to FIG. As shown in FIG. 7A, when the own vehicle starts to change lanes, the direction of the own vehicle changes and the preceding vehicle deviates from the measurement area of the inter-vehicle distance sensor 11 (step S103: Yes). And as shown in FIG.7 (b), the own vehicle can fully accelerate according to an accelerator opening irrespective of a setting limiter speed (step S108), and can overtake the preceding vehicle rapidly. 7A and 7B, if there is a preceding vehicle in the lane after the lane change, the preceding vehicle is detected (step S103: No), so the processing of steps S101 to S107 is performed. Is repeated and the vehicle does not fully accelerate.

  Next, the operation of the vehicle speed limiting device 100 when the process is repeated in the routes of steps S101 and S108 in FIG. 2 will be specifically described. That is, a case will be described in which the kick-down switch is not ON because the driver has not depressed the accelerator pedal to the fully open position. In this case, the vehicle speed limiting device 100 performs conventional ASL control (step S108), and controls the host vehicle as described below. First, when the host vehicle speed is equal to or lower than the set limiter speed, the host vehicle does not accelerate beyond the set limiter speed. Next, when the host vehicle speed has already exceeded the set limiter speed, the host vehicle travels at a speed corresponding to the accelerator opening until the host vehicle speed returns below the set limiter speed. In this case, after the host vehicle speed once returns below the set limiter speed, the host vehicle does not accelerate beyond the set limiter speed.

FIG. 8 is a diagram illustrating changes in the host vehicle speed described with reference to FIGS. In FIG. 8, the own vehicle speed at the time of FIG. 5 (a) is indicated by a point a, the own vehicle speed at the time of FIG. 5 (b) is indicated by a point b, and at the time of FIG. 6 (c). The vehicle speed of the vehicle is indicated by a point c, and the vehicle speed at the time of FIG. 6D is indicated by a point d. Solid lines passing through the points a to d indicate changes in the host vehicle speed described with reference to FIGS. 5 and 6. As can be seen from the solid line passing through the points a to d, the acceleration of the host vehicle decreases as the surplus inter-vehicle distance decreases (see FIGS. 5 and 6). Further, as can be seen from the solid line passing through the points a to d, the acceleration of the host vehicle becomes 0 (m / s ² ) when the surplus inter-vehicle distance becomes 0 m or less. The dotted line shown in FIG. 8 indicates the change in the host vehicle speed when the inter-vehicle distance described with reference to FIG. 7 cannot be measured (step S103: Yes). In this case, since the host vehicle is fully accelerated, the dotted line has a large inclination. In addition, the dotted line shown in FIG. 8 is branched from the continuous line which connects the point c and the point d as an example. However, this dotted line may be branched from any of the solid lines in FIG. This is because, as can be understood from the description using FIG. 7, the host vehicle starts full acceleration when the preceding vehicle departs from the measurement area (step S <b> 103: Yes).

  As described above (see FIG. 2), the vehicle speed limiting device 100 according to the first embodiment performs conventional ASL control when the inter-vehicle distance is equal to or greater than the suppression acceleration distance. That is, the host vehicle fully accelerates when the ON of the kick down switch is detected, and does not accelerate beyond the set limiter speed when the ON of the kick down switch is not detected. The vehicle speed limiting device 100 according to the first embodiment determines the safe inter-vehicle distance according to the relative speed between the host vehicle and the preceding vehicle when the inter-vehicle distance is less than the suppression acceleration distance, and determines the safe inter-vehicle distance from the inter-vehicle distance. Subtract the distance to calculate the extra vehicle distance. Then, a target speed corresponding to the surplus inter-vehicle distance is determined every predetermined unit time α seconds, and the host vehicle is accelerated at an acceleration that reaches the target speed after the predetermined unit time α. That is, when the inter-vehicle distance is less than the suppression acceleration distance, the host vehicle does not perform full acceleration even when the kick-down switch is turned on and travels at a safe acceleration corresponding to the inter-vehicle distance.

  Thus, according to the vehicle speed limiting device 100 according to the first embodiment, even when there is a preceding vehicle, the driver intentionally accelerates the host vehicle safely exceeding the set limiter speed. be able to.

  In the above description, the case where the driver applies the brake by stepping on the brake pedal or the like is not described. However, the driver can naturally reduce the speed of the vehicle by applying the brake at any time.

  Further, in the above, the risk that the own vehicle collides with the preceding vehicle is greatly reduced by changing the safe inter-vehicle distance according to the relative speed between the own vehicle and the preceding vehicle (see FIG. 3). However, the safe inter-vehicle distance does not depend on the relative speed between the host vehicle and the preceding vehicle, and may always be set to a constant value (for example, 50 m). In this case, the process of step S104 in FIG. 2 is omitted. In this case, the effect of reducing the risk that the own vehicle collides with the preceding vehicle is reduced as compared with the case where the safe inter-vehicle distance is changed according to the relative speed between the own vehicle and the preceding vehicle.

  Further, the safe inter-vehicle distance may be made to depend on the own vehicle speed instead of depending on the relative speed between the own vehicle and the preceding vehicle. Specifically, the value of the safe inter-vehicle distance may be changed so as to increase as the value of the host vehicle speed increases. In this case, the engine ECU 12 determines a safe inter-vehicle distance corresponding to the host vehicle speed notified from the speed sensor 14 in step S104 of FIG. As a result, the risk of the host vehicle colliding with the preceding vehicle can be reduced as compared with the case where the safe inter-vehicle distance is always set to a constant value.

  Further, the safe inter-vehicle distance may be made to depend on the relative speed between the host vehicle and the preceding vehicle and the host vehicle speed. This will be specifically described below. FIG. 9 is a diagram illustrating an example of a correspondence relationship among the relative speed, the host vehicle speed, and the safe inter-vehicle distance. As shown in FIG. 9, the value of the safe inter-vehicle distance increases as the relative speed value decreases, and increases as the host vehicle speed value increases. In this case, the engine ECU 12 determines a safe inter-vehicle distance corresponding to the host vehicle speed and the relative speed in step S104 of FIG. As a result, the vehicle speed limiting device 100 can further greatly reduce the risk that the host vehicle will collide with the preceding vehicle.

(Second Embodiment)
The vehicle speed limiting device 200 according to the second embodiment is a vehicle speed limit according to the first embodiment in that the measurement area for measuring the distance between the host vehicle and the preceding vehicle is moved according to the steering angle of the host vehicle. Different from the device 100.

  FIG. 10 is a block diagram illustrating a configuration example of the vehicle speed limiting device 200 according to the second embodiment. As shown in FIG. 10, the vehicle speed limiting device 200 has a configuration in which the inter-vehicle distance sensor 11 is replaced with an inter-vehicle distance sensor 21 with respect to the vehicle speed limiting device 100 according to the first embodiment shown in FIG. 1. In the following, the same components as those of the vehicle speed limiting device 100 of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted in principle.

  The inter-vehicle distance sensor 21 differs from the inter-vehicle distance sensor 11 of the vehicle speed limiting device 100 only in that the inter-vehicle distance measurement area is moved according to the steering angle of the host vehicle.

  FIG. 11 is a flowchart for explaining the operation of the vehicle speed limiting device 200 according to the second embodiment. The flowchart of FIG. 11 is obtained by replacing step S102 with step S202 with respect to the flowchart of FIG. 2 described in the first embodiment. In the following, the same steps as those in the flowchart of FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted in principle. Hereinafter, the operation of the vehicle speed limiting device 200 will be described with reference to FIGS. 10 and 11.

  In step S202, the inter-vehicle distance sensor 21 detects the preceding vehicle by moving the measurement area according to the steering angle of the host vehicle. For example, the inter-vehicle distance sensor 21 similarly tilts the measurement area by 10 ° in the clockwise direction when the steering angle is 10 ° in the clockwise direction. FIG. 12 is a diagram for explaining a measurement area of the inter-vehicle distance sensor 21. As shown in FIG. 12 (a), the measurement area is inclined by θ in the clockwise direction, similarly to the steering angle. Moreover, as shown in FIG.12 (b), when a steering angle is 0 degree, a detection area faces the front direction of the own vehicle like the vehicle speed limiting device 100 of 1st Embodiment (FIGS. 5-5). 7). In addition, since the other operation | movement of the inter-vehicle distance sensor 21 in step S202 is the same as the operation | movement of the inter-vehicle distance sensor 11 in step S102 of FIG. 2, the description is abbreviate | omitted.

  Here, it generally takes a little time for the direction of the vehicle to change after the steering wheel is turned and the direction of the wheels changes. Therefore, in the case of overtaking the preceding vehicle, etc., in the vehicle speed limiting device 100 according to the first embodiment, the preceding vehicle moves out of the measurement area when the direction of the own vehicle is changed. It takes a little time (see FIG. 7). On the other hand, in the vehicle speed limiting device 200 according to the second embodiment, since the preceding vehicle deviates from the measurement area when the direction of the wheels changes, the preceding vehicle is measured earlier than the vehicle speed limiting device 100 according to the first embodiment. Out of the area (see FIG. 12A). As a result, according to the vehicle speed limiting device 200 of the second embodiment, a quick acceleration operation can be performed when the preceding vehicle is overtaking.

  FIG. 13 is a diagram for explaining a measurement area when the host vehicle including the vehicle speed limiting device 200 travels on a curved road. As shown in FIG. 13, since the measurement area moves according to the steering angle, even if the vehicle travels on a curve, a preceding vehicle traveling in the adjacent lane is not detected. That is, even when traveling on a curve, the vehicle speed limiting device 200 can detect a preceding vehicle that travels in the lane in which the host vehicle travels. Thus, the vehicle speed limiting device 200 according to the second embodiment does not erroneously detect a preceding vehicle traveling in the adjacent lane even when traveling on a curve.

  As described above, according to the vehicle speed limiting device 200 of the second embodiment, smoother travel is achieved when passing the preceding vehicle while obtaining the same effect as the vehicle speed limiting device 100 of the first embodiment. Is possible. Furthermore, according to the vehicle speed limiting device 200 of the second embodiment, stable control is possible without erroneously detecting a preceding vehicle traveling in the adjacent lane even when traveling on a curve.

(Third embodiment)
The vehicle speed limiting device 300 according to the third embodiment differs from the vehicle speed limiting device 200 according to the second embodiment in that the target speed is corrected according to the host vehicle speed and the steering angle of the host vehicle.

  FIG. 14 is a block diagram illustrating a configuration example of a vehicle speed limiting device 300 according to the third embodiment. As shown in FIG. 14, the vehicle speed limiting device 300 is different from the vehicle speed limiting device 200 according to the second embodiment shown in FIG. 10 in that the inter-vehicle distance sensor 21 is replaced with an inter-vehicle distance sensor 31 and the engine ECU 12 is replaced with an engine ECU 32. This is a replacement configuration. In the following, the same components as those in the vehicle speed limiting device 200 of the second embodiment are denoted by the same reference numerals, and the description thereof will be omitted in principle.

  The inter-vehicle distance sensor 31 notifies the detected steering angle to the engine ECU 32 in addition to the operation performed by the inter-vehicle distance sensor 21 of the vehicle speed limiting device 200.

  The engine ECU 32 calculates the target speed in the same manner as the engine ECU 12 of the vehicle speed limiting device 200, and then corrects the calculated target speed according to the host vehicle speed and the steering angle.

  FIG. 15 is a flowchart for explaining the operation of the vehicle speed limiting device 300 according to the third embodiment. The flowchart of FIG. 15 is obtained by replacing step S202 with step S302, adding step S350 after step S106, and replacing step S107 with step S307 with respect to the flowchart of FIG. 11 described in the second embodiment. is there. In the following, the same steps as those in the flowchart of FIG. 11 are denoted by the same reference numerals, and the description thereof will be omitted in principle. Hereinafter, the operation of the vehicle speed limiting device 300 will be described with reference to FIGS.

  In step S302, the inter-vehicle distance sensor 31 performs an operation of notifying the engine ECU 32 of the detected steering angle of the host vehicle, in addition to the operation performed by the inter-vehicle distance sensor 21 of the vehicle speed limiting device 200 of the second embodiment.

  In step S350, the engine ECU 32 corrects the target speed calculated in step S106 in accordance with the host vehicle speed notified from the speed sensor 14 and the steering angle notified from the inter-vehicle distance sensor 31. FIG. 16 is an example of a table used by the engine ECU 32 to correct the target speed. Based on the host vehicle speed and the steering angle, a value for correcting the target speed (hereinafter referred to as a corrected speed) is determined by the table of FIG. As can be seen from the table of FIG. 16, the target speed is corrected to a smaller speed as the rudder angle is larger. Moreover, the target speed is corrected to a lower speed as the host vehicle speed is higher. Further, when the steering angle is 0 ° (when the host vehicle is traveling straight), the target speed is not corrected. In other words, the target speed is corrected to a smaller speed as the steering wheel is made larger or the host vehicle speed is higher.

  Next, in step S307, the engine ECU 32 controls the electronic throttle 13 to accelerate the host vehicle for α seconds at an acceleration that reaches the corrected target speed after a predetermined unit time α seconds.

  As described above, the vehicle speed limiting device 300 according to the third embodiment corrects the target speed according to the steering angle and the host vehicle speed and suppresses acceleration. As a result, according to the vehicle speed limiting device 300 according to the third embodiment, the vehicle is controlled based on the rudder angle and the vehicle speed while obtaining the same effect as the vehicle speed limiting device 200 of the second embodiment. It is possible to accelerate safely.

(Fourth embodiment)
The vehicle speed limiting device 400 according to the fourth embodiment is different from the vehicle speed limiting device 100 according to the first embodiment in that the target speed is corrected according to the host vehicle speed and the distance from the host vehicle to the next corner. Different.

  FIG. 17 is a block diagram illustrating a configuration example of a vehicle speed limiting device 400 according to the fourth embodiment. As shown in FIG. 17, the vehicle speed limiting device 400 has a configuration in which the engine ECU 12 is replaced with an engine ECU 42 with respect to the vehicle speed limiting device 100 according to the first embodiment shown in FIG. The engine ECU 42 uses information notified from the navigation system 45. In the following, the same components as those of the vehicle speed limiting device 100 of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted in principle.

  The navigation system 45 is a normal navigation system that guides the host vehicle to a destination. The navigation system 45 notifies the engine ECU 42 of the distance between the host vehicle and the next corner as corner information.

  The engine ECU 42 calculates a target speed in the same manner as the engine ECU 12 of the vehicle speed limiting device 100, and then corrects the calculated target speed according to the host vehicle speed and corner information.

  FIG. 18 is a flowchart for explaining the operation of the vehicle speed limiting device 400 according to the fourth embodiment. The flowchart of FIG. 18 is obtained by adding step S450 after step S106 to the flowchart of FIG. 2 described in the first embodiment, and replacing step S107 with step S407. In the following, the same steps as those in the flowchart of FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted in principle. Hereinafter, the operation of the vehicle speed limiting device 400 will be described with reference to FIGS. 17 and 18.

  In step S450, the engine ECU 42 corrects the target speed calculated in step S106 according to the host vehicle speed notified from the speed sensor 14 and the corner information notified from the navigation system 45. FIG. 19 is an example of a table used by the engine ECU 42 to correct the target speed. Based on the own vehicle speed and the corner information, a speed for correcting the target speed (hereinafter referred to as a correction speed) is determined by the table of FIG. As can be seen from the table in FIG. 19, the target speed is corrected to a smaller speed as the distance from the host vehicle to the next corner is smaller. Moreover, the target speed is corrected to a lower speed as the host vehicle speed is higher. That is, the target speed is corrected to a lower speed as the host vehicle approaches the corner and the host vehicle speed increases.

  Next, in step S407, the engine ECU 42 controls the electronic throttle 13 to accelerate the host vehicle for α seconds at an acceleration that reaches the corrected target speed after a predetermined unit time α seconds.

  As described above, the vehicle speed limiting device 400 according to the fourth embodiment corrects the target speed according to the distance from the host vehicle to the next corner and the host vehicle speed to suppress acceleration. Thus, according to the vehicle speed limiting device 400 according to the fourth embodiment, the distance from the host vehicle to the next corner and the host vehicle speed can be obtained while obtaining the same effect as the vehicle speed limiting device 100 of the first embodiment. Based on the above, it becomes possible to accelerate the host vehicle safely.

  In the fourth embodiment, the vehicle speed limiting device 400 has been described as a modification of the vehicle speed limiting device 100 of the first embodiment. However, the vehicle speed limiting device 400 may be a modification of the vehicle speed limiting device 200 of the second embodiment or the vehicle speed limiting device 300 of the third embodiment.

(Fifth embodiment)
The vehicle speed limiting device 500 according to the fifth embodiment differs from the vehicle speed limiting device 100 according to the first embodiment in that the vehicle speed is reduced by applying a brake when the marginal inter-vehicle distance is a value of 0 or less. .

  FIG. 20 is a block diagram illustrating a configuration example of a vehicle speed limiting device 500 according to the fifth embodiment. As shown in FIG. 20, the vehicle speed limiting device 500 has a configuration in which the engine ECU 12 is replaced with an engine ECU 52 with respect to the vehicle speed limiting device 100 according to the first embodiment shown in FIG. 1. In the following, the same components as those of the vehicle speed limiting device 100 of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted in principle.

  FIG. 21 is a flowchart for explaining the operation of the vehicle speed limiting device 500 according to the fifth embodiment. The flowchart of FIG. 21 is obtained by replacing step S106 with step S506 and replacing step S107 with step S507 with respect to the flowchart of FIG. 2 described in the first embodiment. In the following, the same steps as those in the flowchart of FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted in principle. The operation of the vehicle speed limiting device 500 will be described below with reference to FIGS.

  In step S506, the engine ECU 52 determines the additional speed using the relationship shown in FIG. 22 instead of determining the additional speed using the relationship shown in FIG. 4 described in the first embodiment. FIG. 22 is a diagram illustrating an example of a correspondence relationship between a surplus inter-vehicle distance and an additional speed. As shown in FIG. 22, when the surplus inter-vehicle distance is a negative value, the additional speed is a negative value. Further, when the marginal inter-vehicle distance is a negative value, the value of the additional speed decreases as the marginal inter-vehicle distance decreases. That is, in step S506, the engine ECU 52 calculates a speed smaller than the current host vehicle speed as the additional speed when the marginal inter-vehicle distance is a negative value. The other operation of the engine ECU 52 in step S506 is the same as the operation of the engine ECU 12 in step S106 of the first embodiment.

  Next, in step S507, the engine ECU 52 controls the electronic throttle 13 or a brake device (not shown) to accelerate the host vehicle for α seconds with the acceleration that becomes the target speed calculated in step S506 after α seconds. Or slow down. That is, the engine ECU 52 applies the brake when the surplus inter-vehicle distance is a negative value.

  As a result, the brake control is performed in step S507 until the surplus inter-vehicle distance becomes a positive value in step S105. As a result, the inter-vehicle distance between the host vehicle and the preceding vehicle returns to the safe inter-vehicle distance. .

  As described above, the vehicle speed limiting device 500 according to the fifth embodiment performs brake control to reduce the host vehicle speed when the inter-vehicle distance between the host vehicle and the preceding vehicle becomes smaller than the safe inter-vehicle distance. Thus, according to the vehicle speed limiting device 500 according to the fifth embodiment, the host vehicle approaches the preceding vehicle over the safe inter-vehicle distance while obtaining the same effect as the vehicle speed limiting device 100 of the first embodiment. In this case, the brake is automatically applied, so that safety can be improved.

  In the fifth embodiment, the vehicle speed limiting device 500 has been described as a modification of the vehicle speed limiting device 100 of the first embodiment. However, the vehicle speed limiting device 500 may be a modification of any of the vehicle speed limiting device 200 of the second embodiment to the vehicle speed limiting device 400 of the fourth embodiment.

  The present invention can be used for a vehicle speed limiting device, a vehicle speed limiting method, and the like, and is particularly useful when it is desired to improve safety in a vehicle speed limiting device and a vehicle speed limiting method that perform ASL control.

1 is a block diagram illustrating a configuration example of a vehicle speed limiting device 100 according to a first embodiment. Flowchart for explaining the operation of the vehicle speed limiting device 100 according to the first embodiment. The figure which shows an example of the correspondence of the relative speed of the own vehicle and a preceding vehicle, and the safe inter-vehicle distance The figure which shows an example of the correspondence of extra vehicle distance and additional speed The figure for demonstrating concretely operation | movement of the vehicle speed limiting apparatus 100 which concerns on 1st Embodiment. The figure for demonstrating concretely operation | movement of the vehicle speed limiting apparatus 100 which concerns on 1st Embodiment. The figure for demonstrating concretely operation | movement of the vehicle speed limiting apparatus 100 which concerns on 1st Embodiment. The figure which shows the change of the own vehicle speed demonstrated using FIGS. The figure which shows an example of the correspondence of relative speed, own vehicle speed, and safe inter-vehicle distance The block diagram which shows the structural example of the vehicle speed limiting apparatus 200 which concerns on 2nd Embodiment. The flowchart for demonstrating operation | movement of the vehicle speed limiting apparatus 200 which concerns on 2nd Embodiment. The figure for demonstrating the measurement area of the inter-vehicle distance sensor 21 of the vehicle speed limiting apparatus 200 which concerns on 2nd Embodiment. The figure for demonstrating the measurement area in case the own vehicle provided with the vehicle speed limiting apparatus 200 which concerns on 2nd Embodiment drive | works the curved road. The block diagram which shows the structural example of the vehicle speed limiting apparatus 300 which concerns on 3rd Embodiment. The flowchart for demonstrating operation | movement of the vehicle speed limiting apparatus 300 which concerns on 3rd Embodiment. An example of a table used by the engine ECU 32 of the vehicle speed limiting device 300 according to the third embodiment to correct the target speed. The block diagram which shows the structural example of the vehicle speed limiting apparatus 400 which concerns on 4th Embodiment. The flowchart for demonstrating operation | movement of the vehicle speed limiting apparatus 400 which concerns on 4th Embodiment. An example of a table used by the engine ECU 42 of the vehicle speed limiting device 400 according to the fourth embodiment to correct the target speed. The block diagram which shows the structural example of the vehicle speed limiting apparatus 500 which concerns on 5th Embodiment. Flowchart for explaining the operation of the vehicle speed limiting device 500 according to the fifth embodiment. The figure which shows another example of the correspondence of extra vehicle distance and additional speed

Explanation of symbols

10 Accelerator sensor 11, 21, 31 Distance between vehicles sensor 12, 32, 42, 52 Engine ECU
13 Electronic throttle 14 Speed sensor 45 Navigation system 100, 200, 300, 400, 500 Vehicle speed limiter

Claims (15)

A vehicle speed limiting device that performs ASL control to limit the speed of the host vehicle below a set limiter speed set by a driver,
An accelerator sensor for detecting that the amount of depression of the accelerator pedal exceeds a predetermined amount;
An inter-vehicle distance sensor for measuring an inter-vehicle distance between the preceding vehicle and the host vehicle;
An engine ECU that performs acceleration control of the host vehicle according to the measured inter-vehicle distance when it is detected that the amount of depression of the accelerator pedal exceeds a predetermined amount during ASL control;
The engine ECU
When the measured inter-vehicle distance is equal to or greater than a predetermined distance, the host vehicle is accelerated at an acceleration according to the amount of depression of the accelerator pedal,
When the measured inter-vehicle distance is less than the predetermined distance, the host vehicle is accelerated at an acceleration limited by an acceleration corresponding to an amount of depression of the accelerator pedal.   The case where the measured inter-vehicle distance is not less than a predetermined distance includes a case where the inter-vehicle distance is not measured because a preceding vehicle does not exist within a measurable distance of the inter-vehicle distance sensor. The vehicle speed limiting device described in 1.   When the measured inter-vehicle distance is less than the predetermined distance, the engine ECU accelerates the host vehicle at an acceleration according to a surplus inter-vehicle distance calculated by subtracting a predetermined safe inter-vehicle distance from the measured inter-vehicle distance. The vehicle speed limiting device according to claim 1, wherein:   The engine ECU calculates a relative speed between the preceding vehicle and the host vehicle using the measured change in the inter-vehicle distance, and determines the predetermined safe inter-vehicle distance according to the calculated relative speed. The vehicle speed limiting device according to claim 3. The calculated relative speed takes a positive value when the measured inter-vehicle distance increases, takes a negative value when the measured inter-vehicle distance decreases,
5. The vehicle speed limiting device according to claim 4, wherein the engine ECU determines a larger value as the predetermined safe inter-vehicle distance as the calculated relative speed value is smaller.   4. The vehicle speed limiting device according to claim 3, wherein the engine ECU determines a smaller value as an acceleration according to the calculated marginal vehicle distance as the calculated marginal vehicle distance is smaller. 5.   7. The vehicle speed limit according to claim 6, wherein the engine ECU determines 0 as a value of acceleration according to the calculated marginal inter-vehicle distance when the calculated marginal inter-vehicle distance value is 0 or less. apparatus.   5. The vehicle speed limiting device according to claim 4, wherein the engine ECU further determines the predetermined safe inter-vehicle distance according to a speed of the host vehicle measured by a speed sensor.   The vehicle speed limiting device according to claim 8, wherein the engine ECU determines a larger value as the predetermined safe inter-vehicle distance as the measured value of the speed of the host vehicle is larger.   The inter-vehicle distance sensor further detects a steering angle of the host vehicle, and moves a measurement area for measuring the inter-vehicle distance between the preceding vehicle and the host vehicle according to the detected steering angle. The vehicle speed limiting device described in 1. The inter-vehicle distance sensor further detects a steering angle of the host vehicle,
The engine ECU further corrects the acceleration according to the calculated marginal inter-vehicle distance according to the detected steering angle and the speed of the host vehicle measured by the speed sensor. The vehicle speed limiting device described.   The engine ECU corrects the acceleration corresponding to the calculated marginal vehicle distance to a smaller value as the detected steering angle is larger, and the calculated marginal vehicle distance as the measured speed of the host vehicle is larger. The vehicle speed limiting device according to claim 11, wherein the acceleration corresponding to the vehicle speed is corrected to a small value.   The engine ECU further corrects the acceleration according to the calculated marginal distance according to the distance value from the own vehicle acquired from the navigation system to the next corner and the speed of the own vehicle measured by the speed sensor. The vehicle speed limiting device according to claim 3, wherein:   The engine ECU corrects the acceleration according to the calculated marginal vehicle distance to a smaller value as the distance value from the acquired own vehicle to the next corner is smaller, and the measured speed of the own vehicle is larger. 14. The vehicle speed limiting device according to claim 13, wherein the acceleration according to the calculated marginal inter-vehicle distance is corrected to a small value. A vehicle speed limiting method for performing ASL control for limiting the speed of the host vehicle to a speed lower than a set limiter speed set by a driver,
Detecting that the amount of depression of the accelerator pedal exceeds a predetermined amount;
Measuring a distance between the preceding vehicle and the own vehicle;
A step of performing acceleration control of the host vehicle according to the measured inter-vehicle distance when it is detected that the amount of depression of the accelerator pedal is equal to or greater than a predetermined amount during ASL control,
In the step of performing acceleration control of the host vehicle,
When the measured inter-vehicle distance is equal to or greater than a predetermined distance, the host vehicle is accelerated at an acceleration according to the amount of depression of the accelerator pedal,
When the measured inter-vehicle distance is less than the predetermined distance, the host vehicle is accelerated at an acceleration limited by an acceleration corresponding to an amount of depression of the accelerator pedal.

Images