JP4506167B2 - Travel speed control device - Google Patents

Description

  The present invention relates to a travel speed control device that controls the travel speed of a host vehicle based on a vehicle speed set by a driver.

2. Description of the Related Art Conventionally, a vehicle follow-up travel control device having a follow-up running mode for a plurality of types of speed ranges has been proposed (for example, see Patent Document 1). In such a vehicle pursuit travel control device, the driver can set the vehicle speed for constant speed travel control that is executed when there is no preceding vehicle during the follow travel mode. When the follow-up running mode is returned, for example, when a transition is made from another follow-up running mode, constant speed running control is executed at the set vehicle speed set in the follow-up running mode.
JP 2002-234358 A

If the follow-up running mode is once canceled and it takes a long time to return, the vehicle speed set by the driver may be forgotten or even the vehicle speed may be set. In such a situation, when returning to the follow-up running mode and executing the constant speed running control at the set speed, the driver feels uncomfortable. In particular, when the set vehicle speed is much higher than the vehicle speed at the time of returning to the speed following traveling mode, the acceleration of the host vehicle is increased, and the driver is strongly discomforted.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a travel speed control device capable of performing constant speed travel control at a set vehicle speed that does not give the driver a sense of incongruity.

In order to solve the above problems, the present invention provides a low-speed preceding vehicle following travel control mode in which the host vehicle follows the preceding vehicle in a low speed range, and a high speed in which the host vehicle has a maximum speed higher than the maximum speed in the low speed range. In the travel speed control device comprising a high-speed preceding vehicle following traveling control mode that follows the preceding vehicle in a region as the traveling control mode, the high-speed preceding vehicle following traveling control mode is restored by an operation of a switch, and the driver sets the vehicle speed. Set by the vehicle speed setting means, and when the preceding vehicle does not exist in the high-speed preceding vehicle following traveling control mode, the vehicle speed set by the vehicle speed setting means is set as the target vehicle speed and the constant speed traveling control of the host vehicle is performed at a constant speed. Control means, the execution time of the low-speed preceding vehicle following travel control mode is measured by the travel control mode execution time measurement means, and the vehicle speed is set by the vehicle speed setting means. And the execution time of the low-speed preceding vehicle following travel control mode measured by the travel control mode execution time measuring means when the mode is shifted from the high-speed preceding vehicle following travel control mode to the low-speed preceding vehicle following travel control mode. When the predetermined time is exceeded, the driver sets the target vehicle speed to the target vehicle speed by the target vehicle speed setting means when the driver operates the switch to return to the high-speed preceding vehicle following traveling control mode, and the driver sets the switch even when operating the driver after the operation sometimes has released release the accelerator pedal, sets the target vehicle speed setting means prior Symbol target vehicle host vehicle speed at the time of the release.
That is, when the driver sets the vehicle speed in the high-speed preceding vehicle following traveling control mode, and then the low-speed preceding vehicle following traveling control mode shifted from the high-speed preceding vehicle following traveling control mode is executed for a predetermined time or more, the setting is performed. Assuming that the driver has forgotten the action, when returning from the high-speed preceding vehicle following travel control mode, the vehicle speed at the time of return is set to the target vehicle speed.
Further, when the driver has released away the accelerator pedal, so as to conform to the driver's intention has set vehicle speed at that time objectives vehicle speed.

According to the present invention, it is possible to prevent the driver from feeling uncomfortable by performing constant speed traveling control at a vehicle speed that the driver has forgotten to set.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.
FIG. 1 is a system configuration diagram showing an embodiment of a vehicle with a preceding vehicle follow-up travel control device to which the travel speed control device of the present invention is applied. This vehicle is a rear wheel drive vehicle in which the rear wheels 1RL and 1RR are driving wheels and the front wheels 1FL and 1FR are driven wheels, and the driving torque of the engine 2 is transmitted to the rear wheels 1RL and 1RR via the automatic transmission 3. Is done.

The rotation state, torque, output, etc. of the engine 2 can be controlled by the engine control device 11. Specifically, the engine rotation state, torque, output, etc. can be controlled by adjusting the throttle valve opening, idle valve opening, ignition timing, fuel injection amount, fuel injection timing, and the like.
The automatic transmission 3 can be controlled by a transmission control device 12. Specifically, by adjusting the working fluid pressure supplied to the clutch and brake in the automatic transmission 3, the selected gear ratio can be changed to obtain a desired reduction ratio.

  The wheels 1FL to 1RR are provided with wheel cylinders 4FL to 4RR constituting so-called disc brakes. The wheel cylinders 4FL to 4RR apply a braking force to the wheels 1FL to 1RR by the supplied brake fluid pressure. The braking force applied to each of the wheels 1FL to 1RR can be controlled by the braking fluid pressure control device 13. Specifically, for example, each wheel cylinder 4FL˜ is increased by increasing the brake fluid pressure as in the driving force control device (TCS) or decreasing the brake fluid pressure as in the anti-skid control device (ABS). The braking fluid pressure to 4RR can be adjusted and the braking force to each wheel 1FL-1RR can be controlled. The braking fluid pressure regulated in the braking fluid pressure control device 13 is supplied from a master cylinder 22 that is boosted by depressing the brake pedal 21.

Each of these control devices controls the running state of the vehicle, and as a result, the running state can be controlled by adjusting the acceleration / deceleration, the longitudinal speed, etc. of the host vehicle.
Of course, these control devices can operate alone, but the overall function is governed by the automatic travel control device 10 including inter-vehicle distance control and preceding vehicle following travel control. The automatic travel control device 10 performs various arithmetic processes to control the travel state of the vehicle, thereby performing inter-vehicle distance control, preceding vehicle following travel control, and the like.

  Further, the vehicle is provided with a CCD camera or the like, for example, a front state detection device 16 for detecting a state in front of the host vehicle, for example, the state of the traveling lane, the presence or absence of a preceding vehicle, or the distance to the preceding vehicle, or each wheel 1FL. A wheel speed sensor 17 for detecting a rotational speed of ˜1RR, an acceleration sensor 18 for detecting longitudinal and lateral accelerations generated in the vehicle, a brake fluid pressure sensor 19 for detecting a brake fluid pressure, and an accelerator opening for detecting an accelerator pedal depression amount A degree sensor 20 is provided. Further, this vehicle is provided with a manual switch 9 for adjusting the traveling state of the host vehicle by a driver's manual input.

Further, this vehicle is provided with a navigation system 7 that detects the position information of the own vehicle by so-called GPS (Global Positioning System). Further, the vehicle is provided with a display and a speaker 23 for presenting the contents of control by the automatic travel control device 10 to an occupant, particularly a driver.
In addition, the vehicle, specifically the steering wheel, is provided with a manual switch 9 for adjusting the traveling state of the host vehicle by a driver's manual input. Details of the manual switch 9 are shown in FIG. In the figure, reference numeral 9a is a start switch for travel control including preceding vehicle follow-up travel control, 9b is a travel control release switch, 9c is a set inter-vehicle distance switch for inputting a set inter-vehicle distance, 9d is an input for a set travel speed, A set / coast switch 9e for changing the set travel speed in the deceleration direction is a resume / accelerate switch for re-inputting the previous set travel speed or changing the set travel speed in the acceleration direction after canceling the travel control.

  Of these, the set inter-vehicle distance switch 9c is not used to input a specific set inter-vehicle distance as a numerical value. For example, the set inter-vehicle distance switch 9c is used to increase or decrease the current inter-vehicle distance. In contrast, when the most standard target inter-vehicle distance is set to “medium”, an input method such as “long” for increasing the set inter-vehicle distance or “short” for decreasing the set inter-vehicle distance is adopted. .

The functions of the resume / accelerate switch 9e and the set / coast switch 9d will be described below.
If the resume / accelerate switch 9e is pressed when the start switch 9a is ON and the vehicle speed of the host vehicle is 30 to 100 km / h, the set travel speed of constant vehicle speed travel control (hereinafter also referred to as ASCD control) is set at that time. At the same vehicle speed, and starts high-speed preceding vehicle following traveling control (hereinafter also referred to as ACC control) that follows the preceding vehicle with the set traveling speed as the upper limit vehicle speed. The ACC control performs control to follow the preceding vehicle when the front state detection device 16 detects the preceding vehicle, and performs ASCD control when the front state detection device 16 cannot detect the preceding vehicle. It can also be set to a mode in which only the ASCD control is performed by the driver's setting.

  If the set / coast switch 9d is pressed when the start switch 9a is ON and the vehicle speed of the host vehicle is 30 to 100 km / h, the set traveling speed of the ASCD control is reset to the previously set vehicle speed. The ACC control is started with the set travel speed as the upper limit vehicle speed. The speed range to be controlled by the ACC control and the set traveling speed of the ASCD are 30 to 100 km / h, and the ACC control is canceled when the host vehicle speed becomes 30 km / h or less.

  Also, if the resume / accelerate switch 9e (or the set / coast switch 9d) is pressed when the start switch 9a is ON and the vehicle speed of the host vehicle is 0 to 30 km / h, the low-speed preceding vehicle following that follows the preceding vehicle is performed. Travel control (hereinafter also referred to as inching control) is started. Note that the speed range to be controlled by inching control is 0 to 45 km / h, and overlaps with the vehicle speed range of the previous ACC control between 30 and 45 km / h.

Inching control performs control to follow the preceding vehicle only when the front state detection device 16 detects the preceding vehicle, and the control is performed when the preceding vehicle cannot be detected and when the vehicle speed exceeds 45 km / h. Canceled.
In order to shift from the ACC control to the inching control, it is necessary to press the set / coast switch 9d in this overlapping region (30 to 45 km / h). Further, in order to shift from inching control to ACC control, it is necessary to press the resume / accelerate switch 9e in this overlapping region.

  Note that if there is a brake operation by the driver during the high-speed preceding vehicle following traveling control, the high-speed preceding vehicle following traveling control is canceled. The vehicle speed at that time is stored as the set travel speed. Therefore, when returning to the high-speed preceding vehicle following traveling control later, it is usually the set traveling speed set by the switch operation by the driver or the vehicle speed when the high-speed preceding vehicle following traveling control was previously canceled. The vehicle travels at a constant speed at the set travel speed.

  Next, calculation processing of the inter-vehicle distance control performed in the automatic travel control device 10 will be described with reference to the flowchart of FIG. This calculation process is executed by a timer interrupt every predetermined sampling time ΔT set to, for example, about 10 msec. In this flowchart, no particular communication step is provided, but the results obtained by the arithmetic processing are updated and stored in the storage device as needed, and necessary information and programs are read from the storage device as needed. Further, the above-described engine control device 11, transmission control device 12, and brake fluid pressure control device 13 communicate with each other at any time, and necessary information and commands are exchanged bidirectionally at any time.

In this calculation processing, first, in step S1, the longitudinal acceleration Xg and lateral acceleration Yg detected by the acceleration sensor 18, the wheel speed Vw _j (j = FL to RR) detected by the wheel speed sensor 17, the accelerator opening. The accelerator opening degree Acc detected by the degree sensor 20, the braking fluid pressure Pm detected by the braking fluid pressure sensor 19, the set traveling speed Vc set by the manual switch 9, and the forward state detecting device 16 The distance d between the preceding vehicle and the engine driving torque Tw controlled by the engine control device 11 is read.

Subsequently, in step S2, the traveling speed V of the host vehicle is calculated from the average values of the front left and right wheel speeds Vw _FL and Vw _FR among the wheel speeds Vwj read in step S1.
Subsequently, in step S3, the difference value between the current value d _(n) and the previous value d _(n-1) of the inter-vehicle distance read in step S1 is divided by the predetermined sampling time ΔT, A relative speed Vr between the host vehicle and the preceding vehicle is calculated.

  Subsequently, in step S4, a target inter-vehicle distance dr corresponding to the traveling speed V of the host vehicle calculated in step S2 is calculated. Specifically, the travel speed V of the host vehicle is multiplied by a predetermined control gain, and a predetermined control constant is summed. The control gain and the control constant are set in accordance with the set inter-vehicle distance requested by the driver inputted by the set inter-vehicle distance switch 9c of the manual switch 9.

Subsequently, in step S5, a target travel speed Vs is calculated. Specifically, the target travel speed Vs is calculated as follows.
First, the value obtained by multiplying the difference value between the target inter-vehicle distance dr calculated in step S4 and the actual inter-vehicle distance d read in step S1 by the proportional control gain, and the relative speed Vr calculated in step S3 are differentiated. The reference target travel speed Vso is calculated from an addition value with the value multiplied by the control gain. Then, the smaller one of the calculated reference target travel speed Vso and the set travel speed Vc read in step S1 is set as the target travel speed Vs.

Subsequently, in step S6, the target acceleration Xgs by, for example, PID (proportional-differential-integral) control is calculated from the difference value between the target traveling speed Vs calculated in step S5 and the traveling speed V of the host vehicle calculated in step S2. calculate.
Subsequently, in step S7, for example, when the target acceleration Xgs calculated in step S6 is negative, that is, when deceleration is required, a value obtained by multiplying the target acceleration Xgs by a brake specification coefficient and the step S1. Of the value obtained by multiplying the read brake fluid pressure Pm by the brake specification coefficient, the larger one is calculated as the target brake fluid pressure Pws _j . The brake specification coefficient is a coefficient determined by, for example, the friction coefficient between the disk rotor pads of each wheel, the wheel cylinder cross-sectional area, the disk rotor effective diameter, the tire rolling radius, and the like.

  Subsequently, at step S8, when the target acceleration Xgs calculated at step S6 is positive, that is, when acceleration is required, a value obtained by multiplying the target acceleration Xgs by a drive system variable, and at step S1. Of the values obtained by multiplying the read accelerator opening degree Acc by the drive system specification variable, the larger one is calculated as the target drive torque Tes. The drive system specification variable is a variable determined by, for example, gear inertia, reduction ratio, transmission efficiency, engine characteristics, and the like.

Subsequently, in step S9, the target braking fluid pressure Pws _j calculated in step S7 and the target driving torque Tes calculated in step S8 are directed to the braking fluid pressure control device 13, the engine control device 11, and the transmission control device 12. Output. Further, the information presenting signal for the target inter-vehicle distance control is output to the display and the speaker 23, and then the process returns to the main program. For example, when the target distance between the vehicles is changed and controlled, for example, content such as “increase the distance between vehicles” is presented by voice or display before the information is presented by the display and the speaker 23.

According to this calculation process, the target travel speed Vs is set by the reference target travel speed Vso obtained based on the set travel speed Vc set by the manual switch 9 or the target inter-vehicle distance dr (steps S4 and S5). Then, the target acceleration Xgs is calculated from the difference between the set target travel speed Vs and the travel speed V of the host vehicle (step S6), and the target brake fluid pressure Pws _j and the target drive torque Tes are set so as to be the target acceleration Xgs. Is output to the braking fluid pressure control device 13, the engine control device 11, and the transmission control device 12, and an information presentation signal for target inter-vehicle distance control is output to the display and the speaker 23 (step S7, Step S8, Step S9).

Next, a setting speed setting (resetting) process performed in the automatic travel control device 10 will be described with reference to the flowchart of FIG. This process is executed by timer interruption every predetermined sampling time.
First, in step S21, it is determined whether or not an accelerator operation determination flag FLG set in step 27 described later is 1. The accelerator operation determination flag FLG is set to 0 as an initial value. If the accelerator operation determination flag FLG is 1 (FLG = 1), the process proceeds to step S28. If the accelerator operation determination flag FLG is not 1 (FLG = 0), the process proceeds to step S22.

In step S22, it is determined whether or not the low-speed preceding vehicle following traveling control (inching control) mode has been switched to the high-speed preceding vehicle following traveling control (ACC control) mode. If the low-speed preceding vehicle following traveling control is switched to the high-speed preceding vehicle following traveling control, the process proceeds to step S23. If the low-speed preceding vehicle following traveling control is not switched to the high-speed preceding vehicle following traveling control, the process proceeds to step S30. .
In step S23, it is determined whether there is a stored vehicle speed, that is, whether a set vehicle speed exists. If there is a stored vehicle speed, the process proceeds to step S24. If there is no stored vehicle speed, the process proceeds to step S30.

In step S24, it is determined whether the low-speed preceding vehicle following traveling control is temporary. Specifically, the execution time of the low-speed preceding vehicle following travel control mode is compared with a predetermined time. For example, the automatic travel control device 10 measures the execution time of the low-speed preceding vehicle following travel control mode.
Here, when the execution time of the low-speed preceding vehicle following traveling control mode is shorter than the predetermined time, it is determined that the low-speed preceding vehicle following traveling control mode is temporary, the process proceeds to step S25, and the low-speed preceding vehicle following traveling control mode is performed. If the execution time is longer than the predetermined time, it is determined that the low-speed preceding vehicle following traveling control is not temporary, and the process proceeds to step S26.
In step S25, the set vehicle speed is maintained. Then, the process shown in FIG. 4 ends.

In step S26, it is determined whether or not there has been an accelerator operation by the driver. If there is an accelerator operation by the driver, the process proceeds to step S27, and if there is no accelerator operation by the driver, the process proceeds to step S30.
In step S27, the accelerator operation determination flag FLG is set to 1.
Subsequently, the process of step S28 is performed. Here, the process of step S28 is a process that proceeds even when the accelerator operation determination flag FLG is 1 in step S21.

  As described above, when it is determined in step S26 that there is an accelerator operation by the driver, the accelerator operation determination flag FLG is set to 1 in subsequent step S27. Thus, at the next processing timing, it is determined that the operation determination flag FLG is 1 in step S1, and the processing skips to the processing in step S28. As a result, as long as the accelerator operation by the driver is continued, the process skips from step S1 to step S28.

In this step S28, it is determined whether or not the driver has released the accelerator operation (released the accelerator). If the driver releases the accelerator operation, the process proceeds to step S29. If the driver has not released the accelerator operation, that is, if the driver is still performing the accelerator operation, the process proceeds to step S25.
In step S29, the vehicle speed when the driver releases the accelerator operation is set to the set vehicle speed. Then, the process shown in FIG. 4 ends.

  On the other hand, if the step S22 is not switched from the low-speed preceding vehicle following traveling control to the high-speed preceding vehicle following traveling control, the step proceeds to the step S23 when there is no stored vehicle speed, or when there is no accelerator operation by the driver in the step S26. In S30, the current vehicle speed (the vehicle speed when returning to the high-speed preceding vehicle following traveling control mode) is set to the set vehicle speed. Then, the process shown in FIG. 4 ends.

  According to this calculation process, when the low-speed preceding vehicle following traveling control mode is switched from the low-speed preceding vehicle following traveling control mode, the stored vehicle speed is present, and the low-speed preceding vehicle following traveling control mode is temporary, the set vehicle speed is maintained. (Steps S22 to S25). That is, the vehicle speed set by the driver using the set / coast switch 9d or the resume / accelerate switch 9e, or the set vehicle speed that is the vehicle speed when the high-speed preceding vehicle following traveling control is canceled is maintained.

  In addition, when the low-speed preceding vehicle following travel control mode is switched from the low-speed preceding vehicle following traveling control mode to the high-speed preceding vehicle following traveling control mode and there is a stored vehicle speed, The vehicle speed is set as the set vehicle speed (step S22, step S23, step S24, step S30). Similarly, when the low-speed preceding vehicle following traveling control mode is not switched to the high-speed preceding vehicle following traveling control mode or when there is no stored vehicle speed, the current vehicle speed is set as the set vehicle speed (steps S22, S23, Step S30).

In addition, even when the low-speed preceding vehicle following travel control mode is switched from the low-speed preceding vehicle following traveling control mode, the stored vehicle speed is present, and the low-speed preceding vehicle following traveling control mode has been executed for a long time, the driver performs the accelerator operation. When this occurs, the vehicle speed when the accelerator operation is released is set as the set vehicle speed (steps S22 to S24, steps S26 to S29).
Thus, the set vehicle speed is maintained, or the set vehicle speed is set or reset according to various conditions. Then, after returning to the high-speed preceding vehicle following traveling control mode, if there is no preceding vehicle at that time, the host vehicle travels at a constant speed at the set vehicle speed as the constant speed traveling control (ASCD control) mode.

Next, the effect in this embodiment is demonstrated.
As described above, the low-speed preceding vehicle following traveling control mode is switched from the low-speed preceding vehicle following traveling control mode to the high-speed preceding vehicle following traveling control mode (specifically, the ASCD control mode), the vehicle speed is stored, and the low-speed preceding vehicle following traveling control mode is executed for a long time. If it is, the current vehicle speed (the vehicle speed when returning to the high-speed preceding vehicle following traveling control mode) is set to the set vehicle speed.
For example, the driver may set the vehicle speed with the resume / accelerate switch 9e during execution of the ASCD control mode, and then shift to the low-speed preceding vehicle following travel control mode. However, if the execution time of the low-speed preceding vehicle following travel control mode is long, the driver may forget that the vehicle speed has been set during the execution of the ASCD control mode. In such a situation, when the low-speed preceding vehicle following traveling control mode is switched to the high-speed preceding vehicle following traveling control mode (specifically, the ASCD control mode), the host vehicle travels at a constant speed at the set vehicle speed. At this time, especially when the set vehicle speed is much higher than the vehicle speed when the mode is switched, the acceleration of the host vehicle increases, which gives the driver a sense of incongruity.

For this reason, even when the stored vehicle speed exists, the low-speed preceding vehicle following travel control mode is executed for a long time and then the high-speed preceding vehicle following travel control mode (specifically, the ASCD control mode) is switched. In order to prevent the driver from feeling uncomfortable, the current vehicle speed is set to the set vehicle speed without maintaining the set vehicle speed.
On the other hand, when the low-speed preceding vehicle following traveling control mode is switched from the low-speed preceding vehicle following traveling control mode to the high-speed preceding vehicle following traveling control mode (specifically, the ASCD control mode), the stored vehicle speed is present, and the low-speed preceding vehicle following traveling control mode is temporary. The set vehicle speed is maintained. As a result, when the low-speed preceding vehicle following traveling control mode is temporarily executed and then switched to the high-speed preceding vehicle following traveling control mode (specifically, the ASCD control mode), the vehicle speed set by the driver is determined. The constant speed running control can be executed. In other words, if the low-speed preceding vehicle following travel control mode is temporary, it is assumed that the driver knows the set vehicle speed, and the driver does not cancel the set vehicle speed. I try not to give it.

  In the case of the navigation system 7 that obtains information that the own vehicle has passed through the toll gate on the expressway, joined or is traveling on a congested road during the low-speed preceding vehicle following travel control mode, The execution of the preceding vehicle follow-up travel control mode can also be handled as being temporary. As a result, if the vehicle passes the toll gate on the highway, merges, or switches to the high-speed preceding vehicle following travel control mode after traveling on a congested road, the set vehicle speed should not be canceled. , So that the driver does not feel uncomfortable.

In the above-described embodiment, the low-speed preceding vehicle following traveling control mode is switched from the low-speed preceding vehicle following traveling control mode to the high-speed preceding vehicle following traveling control mode (specifically, the ASCD control mode). Even when the operation is performed for a long time, when the driver performs an accelerator operation, the vehicle speed when the accelerator operation is released is set as the set vehicle speed.
That is, when the driver is operating the accelerator, it is determined that the driver has an intention to accelerate, without maintaining the set vehicle speed (step S25) or setting the current vehicle speed (step S30). The vehicle speed when the accelerator operation is released is set as the set vehicle speed. As a result, the set vehicle speed most in line with the driver's intention to accelerate can be achieved.

  In the high-speed preceding vehicle follow-up travel control mode, even if the driver is accelerating by operating the accelerator even within the target vehicle control target travel speed region of the high-speed preceding vehicle follow-up travel control mode, The accelerator operation by will be prioritized. Then, when the driver releases the accelerator operation, the high-speed preceding vehicle following travel control mode is restored. Therefore, the vehicle speed when the accelerator operation is released is the vehicle speed when returning to the high-speed preceding vehicle following travel control mode.

The embodiment of the present invention has been described above. However, the present invention is not limited to being realized as the above-described embodiment.
That is, in the above-described embodiment, the case has been described in which the preceding vehicle following traveling control device performs the constant speed traveling control by the set vehicle speed on the assumption that the preceding vehicle following traveling control device has the functions of the low speed preceding vehicle following traveling control and the high speed preceding vehicle following traveling control. However, the present invention is not limited to this. For example, a case where only ACC control and ASCD control are provided, or ACC control and inching control may function as one follow-up running control. That is, the present invention can be applied to any device that can temporarily cancel the constant speed traveling control and that performs the control at the set vehicle speed when the constant speed traveling control is restored.

  In the above description of the embodiment, the high-speed preceding vehicle following traveling control (ACC control), the low-speed preceding vehicle following traveling control (inching control), and the constant speed traveling control (ASCD control) each realize the traveling control mode. The set / coast switch 9d and the resume / accelerate switch 9e realize vehicle speed setting means for the driver to set the vehicle speed, and the automatic travel control device 10 is configured to use the vehicle speed setting means during the constant speed travel control mode. A constant speed travel control means for performing constant speed travel control of the host vehicle with the vehicle speed set by the vehicle as a target vehicle speed and a travel control mode execution time measurement means for measuring the execution time of travel control modes other than the constant speed travel control mode are realized. The processing of steps S22 to S24 and steps S26 to S30 in FIG. The execution of the other travel control mode measured by the travel control mode execution time measurement means when the vehicle speed is set by the vehicle speed setting means and then the constant speed travel control mode is shifted to another travel control mode. When the time is equal to or longer than the predetermined time, target vehicle speed setting means is set for setting the own vehicle speed at the time of returning to the constant speed traveling control mode to the target vehicle speed.

It is a vehicle block diagram which shows an example of the vehicle with a preceding vehicle following travel control apparatus of embodiment of this invention. It is a figure which shows the structure of the manual switch of FIG. It is a flowchart which shows the arithmetic processing for the inter-vehicle distance control performed with the automatic travel control apparatus of FIG. It is a flowchart which shows the arithmetic processing of the subroutine performed by the arithmetic processing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 FL-1RR is a wheel 2 Engine 3 Automatic transmission 4FL-4RR Wheel cylinder 7 Navigation system 9 Manual switch 10 Automatic travel control apparatus 11 Engine control apparatus 12 Transmission control apparatus 13 Braking fluid pressure control apparatus 16 Front state detection apparatus 17 Wheel Speed sensor 18 Acceleration sensor 19 Brake fluid pressure sensor 20 Accelerator opening sensor 21 Brake pedal 22 Master cylinder 23 Display and speaker

Claims (1)

Low-speed preceding vehicle following travel control mode in which the host vehicle follows the preceding vehicle in the low speed range, and high-speed preceding vehicle tracking in which the host vehicle follows the preceding vehicle in a high speed range where the maximum speed is higher than the maximum speed in the low speed range. In a traveling speed control device comprising a traveling control mode as a traveling control mode,
The high-speed preceding vehicle following traveling control mode is restored by operating a switch.
Vehicle speed setting means for the driver to set the vehicle speed;
In the high-speed preceding vehicle following traveling control mode, when there is no preceding vehicle, constant speed traveling control means for performing constant speed traveling control of the host vehicle with the vehicle speed set by the vehicle speed setting means as a target vehicle speed;
Travel control mode execution time measuring means for measuring an execution time of the low-speed preceding vehicle following travel control mode;
The low-speed preceding vehicle measured by the traveling control mode execution time measuring unit when the vehicle speed is set by the vehicle speed setting unit and then the high-speed preceding vehicle following traveling control mode is shifted to the low-speed preceding vehicle following traveling control mode. When the execution time of the follow-up running control mode is equal to or longer than a predetermined time, the driver sets the target vehicle speed to the target vehicle speed when the driver operates the switch and returns to the high-speed preceding vehicle follow-up running control mode. There even when operating the switch, sometimes the driver after the operation was canceled by releasing the accelerator pedal, and the target vehicle speed setting means for setting prior Symbol target vehicle host vehicle speed at the time of the release,
A travel speed control device comprising:

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