JPH1142955A - Vehicular running control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent hunting with running safety on a curved road assured and with driver's running feeling further agreed in a running control device for following up a preceding car. SOLUTION: An inter-vehicle control ECU 12 carries out acceleration control by means of target acceleration for following up a preceding upon detecting the preceding car. On a curved road, the upper limit of the acceleration is determined based on a curve curvature and following-car speed to direct the result to an engine ECU 14 for accelerating the following-up car. Acceleration is not uniformly prohibited on the curved road, yet the upper limit value is determined. Thus, gentle acceleration is allowed at low speed, for example, to agree with driver's feeling and to prevent sudden acceleration after passing the curved road.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a vehicle traveling control device,
In particular, it relates to acceleration control during turning.

[0002]

2. Description of the Related Art For example, Japanese Unexamined Utility Model Publication No. 59-146544 discloses a system in which, when there is a preceding vehicle, the following vehicle is controlled by controlling the distance to the preceding vehicle. Discloses that following is performed by uniformly prohibiting acceleration so as to prevent a sudden approach to a preceding vehicle on a curved road.

[0003]

However, according to this technique, acceleration is uniformly prohibited even in a situation where the vehicle is running at a low vehicle speed such that the driver does not feel uncomfortable even if the vehicle accelerates while driving on a curve. As a result, there is a problem that the driving feeling does not match the driving feeling of the driver.

In addition, since acceleration is uniformly prohibited on a curved road, the distance between the vehicle and the preceding vehicle is increased, and acceleration after passing through a curve is further increased, causing a problem of hunting of control.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and has as its object to ensure the safety of traveling on a curved road while further matching the driving feeling of a driver and preventing hunting. An object of the present invention is to provide a travel control device capable of achieving the following.

[0006]

According to a first aspect of the present invention, there is provided a vehicle travel control device for performing constant acceleration control for controlling a vehicle speed to a predetermined target value. A control unit for determining an upper limit value of a target acceleration in the constant acceleration control based on the constant acceleration control.

According to a second aspect of the present invention, there is provided a vehicle traveling control apparatus having a radar for recognizing a preceding vehicle and control means for controlling the acceleration of the own vehicle based on an output from the radar. The upper limit of the target acceleration is determined based on the curvature and the own vehicle speed.

In a third aspect based on the second aspect, the control means performs constant acceleration control so as to set the own vehicle speed to a target vehicle speed when the preceding vehicle is not detected by the radar. When a vehicle is detected, constant acceleration control is performed at the target acceleration. Here, the constant acceleration control means that the traveling control of the own vehicle is performed at a target acceleration determined so that the state of the own vehicle becomes the target vehicle speed, and is not limited to the control by the constant acceleration. Instead, the target acceleration may be changed according to various states.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In the following description,
"Cruise control" or "cruise function" means that if there is a preceding vehicle, the vehicle follows the vehicle while keeping the distance to the preceding vehicle at the target distance, and if there is no preceding vehicle, it is set by the driver This means running at a constant speed at the vehicle speed.

FIG. 1 is a block diagram showing the overall configuration of the present embodiment. A scanning type laser radar 10 is provided on a front bumper of the vehicle, and sends a laser beam forward, and a distance and a direction from a reflected light to an object ahead,
Detect relative speed. An inter-vehicle control ECU (electronic control unit) 12 is connected to the scan type laser radar 10 to determine a vehicle to follow based on data from the laser radar 10 so that an interval with the following vehicle becomes a target interval. The acceleration (or deceleration) is determined. Vehicle control EC
An engine ECU 14 is connected to U12, and implements a cruise control function based on data from the headway control ECU12. Specifically, this engine EC
U14 has an electronic throttle actuator 24 and EC
A T (electronic control transmission) solenoid 26 is connected to drive an electronic throttle actuator in accordance with a target acceleration supplied from the headway control ECU 12 or in response to a downshift request (deceleration request) supplied from the headway control ECU 12. The shift is changed to a low speed side to cause engine braking.

The engine ECU 14 has an ECT mode switch 16, a cruise control switch 18,
A stop lamp switch 20 and a vehicle speed sensor 22 are connected. The cruise control switch 18 is for performing each operation of ON / OFF of the cruise function of the engine ECU 14, setting of the vehicle speed, acceleration, deceleration, and control cancellation, and details thereof will be described later. EC
The T mode switch 16 is a switch for the driver to set an ECT mode (for example, a power mode or a snow mode). When the driver sets the ECT mode to a snow mode (a mode in which the vehicle can start in a second gear). Means that the engine ECU 14 cancels the cruise function. This is to prevent the cruise control from being performed on slippery roads such as snowy roads and icy roads. The cruise function can be canceled by canceling the cruise function in operation or by turning on the cruise function using the cruise control switch 18. This includes prohibiting the transition to the cruise function even at times. Note that the driver does not operate the ECT mode switch 16 but the engine ECU 14
When the ECT is automatically set to the snow mode by detecting that the wheel is slipping on the basis of the wheel speed and the output from the G sensor inside, and determining that the road is a low friction road (low μ road),
It is desirable to cancel the cruise function at the same time as setting the snow mode. The stop lamp switch 20 is for detecting a brake operation by the driver,
Engine EC when the driver performs the brake operation
U14 cancels the cruise function.

A VSC (vehicle attitude stabilization control) -ECU 28 is connected to the engine ECU 14.
A steering sensor 30 and a warning buzzer 32 are connected to the C-ECU 28. When the VSC-ECU 28 detects that the vehicle has over-steered or under-steered based on the detection from the steering sensor 30, the VSC-ECU 28 lowers the output of the engine and applies a braking force to the front wheels or the rear wheels to stabilize the turning motion of the vehicle. When the system operates, the warning buzzer 32 is driven to alert the driver. However, if the inter-vehicle distance with the following vehicle is too close during the cruise function, the engine ECU 14 sets the VSC-. The alarm buzzer 32 is driven via the ECU 28 to call the driver's attention (for example,
(E.g., an audible alarm sounds). That is, the alarm buzzer 32 has both functions of the VSC operation alarm and the inter-vehicle alarm during the cruise function. The steering angle detected by the steering sensor 30 is used for the VSC and is also supplied to the engine ECU 14 to be used particularly for a cruise function on a curved road. Various devices are connected to the engine ECU 14 via a body multiplex communication system 34. Specifically, a tail lamp switch 36, a wiper switch 38, and a meter 40 are connected. The tail lamp switch 36 is for detecting the lighting of the tail lamp, that is, night running, and when the tail lamp switch is in the ON state, the engine ECU 14
Sets the target inter-vehicle distance longer than during the day. A specific setting method will be described later. Wiper switch 3
Numeral 8 is for detecting the operating state of the wiper, that is, running in rainy weather. When the wiper switch 38 is ON, the engine ECU 14 cancels the cruise function. The meter display 40 is one of the features of the present embodiment, and displays information specific to the cruise function in addition to the normal speed and the engine speed. The information specific to the cruise function includes detection of a preceding vehicle, an inter-vehicle time representing an inter-vehicle distance, a set vehicle speed, a state of the cruise function, a fail mode, and the like. The inter-vehicle time is a physical quantity expressing the inter-vehicle distance by time, and has a relation of inter-vehicle time = inter-vehicle distance / vehicle speed.
Therefore, there is a target inter-vehicle time corresponding to the target inter-vehicle distance that is the target of the follow-up control at a ratio of 1: 1. In this embodiment, the inter-vehicle time switch 44 is provided so that the driver can appropriately adjust the target inter-vehicle time. . The inter-vehicle time switch 44 is connected to the meter display 40, and the inter-vehicle time set by the driver is displayed on the display as it is, and is supplied to the engine ECU 14 via the body multiplex communication system 34 and used for cruise control. As the inter-vehicle time that can be set by the driver, three stages of long, medium and short are prepared as follows.

[0013] Long: 2.4 (sec) Medium: 2.0 (sec) Short: 1.8 (sec) When the vehicle is running at 80 km / h, the time between each vehicle is represented by a distance. Length is about 55m, inside is about 45
m and short are about 40 m. These inter-vehicle times are
It is displayed on the display 40 so that it is possible to see at a glance which inter-vehicle time is currently set. In the above description, when the tail lamp switch 36 is in the ON state, the inter-vehicle distance is set to be longer than during the day. Specifically, the inter-vehicle time is set to be longer, and α1, α2, α3
Is changed as a constant from 2.4 (sec) in the daytime to 2.4 + 1α (sec) and 2.0 (sec) in the daytime.
c) is changed to 2.0 + α2 (sec), and 1.8 (α) is changed to 1.8 + α3 (sec) in a short time of 1.8 (sec).
To change. Α according to the long, middle, short
It is preferable to change each of the above constants so that 1>α2> α3. Further, these α1, α2, and α3 may be selected in advance by the driver.

FIG. 2 shows the configuration of the laser radar 10. The light emitting circuit 10b pulse-drives the laser diode LD10c based on a command from the CPU 10a. The pulse laser light from the laser diode LD10c is shaped by the lens 10d, reflected by the mirror 10e, and enters the polygon mirror f. The polygon mirror has six surfaces and rotates around a rotation axis. The rotation of the polygon mirror 10f scans a pulse laser beam in a horizontal plane (in the horizontal direction with respect to the traveling direction). Further, each surface of the polygon mirror 10f has a different inclination angle sequentially, and scans the pulse laser light in the vertical direction with respect to the traveling direction each time the incident surface of the pulse laser light changes.

On the other hand, when there is a preceding vehicle, the pulse laser light reflected by the preceding vehicle is incident on the photodiode 10h via the light receiving lens 10g, converted into an electric signal, and supplied to the light receiving circuit 10i. The received light pulse signal is further supplied to a time measurement IC 10j, and the time from when the pulse laser light is transmitted to the time when it is reflected and received by the preceding vehicle is measured, and supplied to the CPU 10a to detect the distance to the preceding vehicle. And a relative speed as a time change is detected. The detected inter-vehicle distance and relative speed are supplied to the CPU 10k, and the CPU 10k supplies these detection data to the inter-vehicle control ECU 12.

FIG. 3 schematically shows a scan range 100 of the laser radar 10. Polygon mirror 10
The pulsed laser light scans in a horizontal plane in a horizontal direction with respect to the traveling direction by being reflected on one of the six reflecting surfaces f. Also, the polygon mirror 10
By scanning off the other reflecting surface of f, scanning is performed in the horizontal direction in a different horizontal plane. The pulsed laser beam in the vertical direction has a total of 6
There are a total of 105 books in the left-right direction corresponding to the rotation angle in one reflection surface. The reach of the laser beam is about 100 m in fine weather. Therefore, if there is a preceding vehicle within 100 m, there is a preceding vehicle, and if it is more than 100 m, there is no preceding vehicle.

FIG. 4 is a layout diagram of the vicinity of the steering wheel 50 in the vehicle interior. A lever-shaped cruise control switch 18 is provided on the right side of the steering shaft, and an inter-vehicle time switch 44 is provided on the steering wheel 50. As described above, the cruise control switch 18 has a function to set ON / OFF of the cruise function, a vehicle speed at the time of constant speed running (when no preceding vehicle is present) and an upper limit vehicle speed at the time of following running, and acceleration / deceleration without using the accelerator pedal. It has a function to perform, a resume function to return from the control non-operation state to the operation state, and the like. Have.

FIG. 5 is an enlarged view of the cruise control switch 18. The cruise control switch 18 is in the form of a lever and can be operated up and down. A main switch 18a which can be pushed (in the direction of arrow a in the figure) is provided on the side. By depressing the main switch 18a, the engine ECU 14
Cruise power is turned on. The power ON state is a standby state of the cruise function, and the driver shifts to the actual cruise function when the driver sets the cruise function after the set vehicle speed and the inter-vehicle time are set. The setting of the cruise function (SET) is executed by lowering the cruise control switch 18. As described above, even when the main switch 18a is pressed, the cruise power is not turned on but remains off during the ECT snow mode or the wiper operation. Further, when it is desired to increase the set vehicle speed, the cruise control switch is kept up, and when it is desired to decrease the set vehicle speed, the cruise control switch is kept down.
These data are supplied to the CU 14. When the driver performs the brake pedal operation during the control operation, that is, during the cruise operation, the control is not operated (the cruise function is canceled). (Resume function).

FIG. 6 is an enlarged view of the inter-vehicle time changeover switch 44. The inter-vehicle time switch 44 is composed of three switches, a mode (MODE) switch 44a for switching the inter-vehicle time in three stages, and a display 4
Function switch 44 for switching 0 (FUNCTION)
b and a reset switch. The inter-vehicle time is always set to be long in the initial state of the engine ON, and is switched from long to middle and further short by operating the mode switch 44a. When the vehicle becomes shorter and further operations are performed, the inter-vehicle time returns to a longer time. The reason why the inter-vehicle time is uniformly initialized in the initial state when the engine is ON is to ensure safety when the vehicle shifts to the following running.
The function switch 44b is for switching between a cruise state display and other displays (for example, an alarm display) on the display 40, and the engine E is turned on during cruise control.
The CU 14 displays the control state (presence / absence of a preceding vehicle and a set vehicle speed). When the driver operates the switch 44b, the display changes to a warning display screen or a drive monitor screen. However, if any change occurs in the cruise state (for example, whether the preceding vehicle is detected or the set vehicle speed changes) while the warning display screen is displayed, the display is automatically switched from the warning screen to the cruise state screen. Switch to If the cruise system is canceled, the inter-vehicle time set at that time (long, medium, short)
May be temporarily stored, and when the control of the cruise system is restarted again, the headway control may be performed based on the stored value.

FIG. 7 shows a display example of the meter display 40. The speed is displayed on the center left side, the engine speed is displayed on the center right side, and the cruise state screen 41 is displayed on the lower part. This screen 41 can be composed of, for example, liquid crystal. An alarm lamp 42 is provided on the left side of the cruise status screen 41, and a cruise power lamp 43 is further provided on the right side.
Is provided. On the cruise state screen 41, the detected preceding vehicle, target inter-vehicle time, own vehicle, and set vehicle speed are displayed. As described above, when the driver operates the function switch 44b of the inter-vehicle time changeover switch 44, this screen is switched to another screen (warning screen or drive monitor screen). In addition, in order to adjust so that the inter-vehicle time is increased when the tail lamp is lit, it is also preferable that when the tail lamp is lit, the screen 41 has a screen color different from the daytime to notify the driver that the inter-vehicle time is adjusted to be increased. is there. If the vehicle approaches the preceding vehicle abnormally while following the preceding vehicle, a warning is given to the driver using the warning buzzer 32 of the VSC. At this time, the engine ECU 4 displays the screen 41 so as to repeat the inversion of light and dark. It is also preferred to control and visually alert the driver.

The alarm lamp 42 is lit when an abnormality occurs in the cruise function. In this case, the engine ECU 14 cancels the cruise function and displays the details of the abnormality on the screen 41. Of course, the alarm buzzer 32
A warning sound can be used to notify the driver. As the warning sound, for example, a "pawn" or the like can be considered to distinguish it from the warning sound "pipipipi" at the time of following the preceding vehicle.

The configuration of the present embodiment is as described above, and the operation will be described in more detail below.

FIG. 8 shows a flowchart of the cruise control process executed by the headway control ECU 12 and the engine ECU 14. When the driver sets the cruise function using the cruise control switch 18 (turns the main switch ON and sets the switch 18 down), the engine ECU 14 determines whether or not the cruise function has been canceled (S101). If the vehicle has not been cancelled, the following control ECU 12 determines whether or not a preceding vehicle has been detected, and if there is a preceding vehicle, the following control ECU 12 and the engine ECU 14 execute the following cruise control (S103). ). If there is no preceding vehicle, the engine ECU 14 compares the current vehicle speed Vn with the set vehicle speed Vm (S104) and determines that Vn <
If it is Vm, acceleration control is performed to set the vehicle speed (S10
5) If the current vehicle speed Vn is substantially equal to the set vehicle speed Vm, a constant speed cruise control for maintaining the current vehicle speed is executed (S106). If the wiper is activated in rainy weather or EC
When shifting to the snow mode of T, when the driver operates the cruise control switch 18 to cancel, when the driver operates the brake, when the vehicle speed falls below a predetermined value (for example, 40 km / h), the cruise function is activated. If an abnormality occurs, for example, YES is determined in S101, and the engine ECU 14 cancels the cruise function (S107).

FIG. 9 shows a detailed flowchart of the engine output control. First, the laser radar 10 detects an inter-vehicle distance and a relative speed with a preceding vehicle (S201),
The inter-vehicle control ECU 12 calculates an inter-vehicle deviation between the target inter-vehicle time and the current inter-vehicle time (S202). Then, the control acceleration (target acceleration) required to reduce the inter-vehicle deviation to zero is calculated (S203) and supplied to the engine ECU 14. The engine ECU 14 controls the engine output by driving the electronic throttle actuator 24 to obtain the control acceleration (S204). If the calculated control acceleration is a large negative value, that is, a large deceleration side, the engine ECU 14 cuts off the overdrive and shifts down by receiving the downshift request supplied from the headway control ECU, and the engine brake To slow down. If there is no preceding vehicle, a target acceleration corresponding to the case where there is no preceding vehicle is set in S203. The details will be described later.

FIG. 10 schematically shows the above processing contents. (A) shows a case where there is no preceding vehicle (100
m, and the vehicle runs at a constant speed at the vehicle speed set by the driver (S106 in FIG. 8).
Constant speed cruise in). (B) is a case where a preceding vehicle that is slower than the set vehicle speed is detected during traveling at a constant speed, and deceleration control is performed so as not to abnormally approach the preceding vehicle (inter-vehicle cruise in S103 in FIG. 8). (C) is a case where the vehicle follows the preceding vehicle, and acceleration / deceleration control is performed such that the inter-vehicle time with the preceding vehicle becomes the target inter-vehicle time with the set vehicle speed as an upper limit (S103 in FIG. 8)
Cruise between vehicles in). (D) is a case where the preceding vehicle has entered the interchange or the service area and is no longer present. In this case, the vehicle gradually accelerates to the set vehicle speed (constant speed cruise in S106 in FIG. 8). The reason why the vehicle gradually accelerates to the set vehicle speed when the preceding vehicle no longer exists is that if the vehicle ahead enters the interchange or the service area and the preceding vehicle disappears, the vehicle rapidly accelerates to the set vehicle speed. This is in consideration of undesirable effects.

As described above, when there is a preceding vehicle,
In order to maintain the target inter-vehicle time, the inter-vehicle control ECU 12 determines the target acceleration based on the relative speed with respect to the preceding vehicle and the inter-vehicle deviation and issues a command to the engine ECU 14, but depending on the road shape, the determined target acceleration is not always appropriate. There is. That is, for example, the following vehicle accelerates rapidly, and the following control ECU 12 determines a relatively large target acceleration to follow the preceding vehicle. However, if the own vehicle is currently traveling on a curved road, the determination is made. If the engine ECU 14 controls the acceleration of the own vehicle in accordance with the target acceleration thus set, a heavy load is imposed on the driver. On the other hand, if the acceleration is uniformly prohibited on the curved road, the acceleration does not match the driving feeling of the driver as in the prior art, and the acceleration control after traveling on the curved road becomes steep, resulting in hunting of the control.

Therefore, in the present embodiment, the headway control ECU
No. 12 solves the above problem by setting an upper limit on the target acceleration and making the upper limit of the target acceleration variable when turning on a curved road.

FIG. 11 is a detailed flowchart of the target acceleration calculation process (S203) in FIG. First, the inter-vehicle control ECU 12 determines whether or not there is a preceding vehicle (S301). If there is a preceding vehicle, it calculates a target acceleration ATn for the preceding vehicle (S30).
2). As described above, the target acceleration ATn is determined based on the inter-vehicle deviation. On the other hand, if there is no preceding vehicle, the acceleration AT0 for reaching the set vehicle speed (target vehicle speed) is set to ATn (S303). This corresponds to the process of S105 in FIG. After temporarily determining the target acceleration, the current lateral acceleration gn is calculated by calculation (S304). Specifically, the vehicle speed signal from the vehicle speed sensor 22 and the steering signal from the steering sensor 30 are transmitted from the engine ECU 14 to the headway control E
The vehicle control ECU 12 is supplied to the CU 12 and first estimates a curve radius (curve curvature) of a curved road from a steering signal and a vehicle speed signal. Then, the lateral acceleration is calculated based on the estimated curve radius and the vehicle speed signal. To estimate the curve radius from the steering signal and the vehicle speed signal, the following relationship between the steering angle θ (deg), the vehicle speed V (km / h), and the curve radius R (m) may be used.

[0029]

R = KR (1 + αV ² + βV ³ ) / θ where KR, α and β are constants. Further, the lateral acceleration g is calculated from the estimated curve radius R (m) and the vehicle speed V (km / h).
To calculate (G), the following equation may be used.

[0030]

Gn = (V / 3.6) ² /R/9.8 Thus, the lateral acceleration gn can be calculated without using a new lateral acceleration sensor. Of course, if there is room in the system, a lateral acceleration sensor can be used. After calculating the lateral acceleration as described above, the following distance control ECU 12 determines a target acceleration upper limit guard value (upper limit value) ATgrdn using a map.

FIG. 12 shows an example of a map for determining the guard value stored in the memory of the following distance control ECU 12 in advance. The horizontal axis is the lateral acceleration gn (G) of the vehicle,
The vertical axis is the upper limit of the target acceleration. When the lateral acceleration during turning is 0 to β / 2 (G), the upper limit of the target acceleration is αkm / h / s, and when the lateral acceleration is 0.1 to β (G), αkm / h / s From 0 to 0 km / h / s. By setting the upper limit value of the target acceleration to be smaller as the lateral acceleration becomes larger, it becomes possible to perform acceleration traveling according to the shape of the curved road. If the lateral acceleration is equal to or more than β (G), the upper limit of the target acceleration is set to a minus value, that is, the target acceleration is set to the deceleration side instead of the acceleration side. When the lateral acceleration is equal to or greater than a certain value, the ride comfort and safety can be more reliably ensured by performing the deceleration control.

Referring back to FIG. 11, after the upper limit value of the target acceleration is determined using the map, the process proceeds to S302 or S303.
It is determined whether or not the target acceleration ATn determined in step (1) is equal to or greater than the upper limit value ATgrdn (S306). If below the upper limit,
The constant acceleration control is executed at the calculated target acceleration ATn to follow the preceding vehicle (when the preceding vehicle is detected), or accelerate at a constant acceleration to the set vehicle speed (when the preceding vehicle is not detected). If there is, the upper limit value ATgrdn is newly set as the target acceleration, and the respective constant acceleration controls are executed (S307).

As described above, the lateral acceleration, which is an index that the driver can feel, is calculated based on the curve curvature (curve radius) and the own vehicle speed, and the upper limit value of the acceleration is determined based on the lateral acceleration. A curve running that matches the feeling can be realized.

In the prior art, acceleration is uniformly prohibited on a curved road. In the present embodiment, gentle acceleration is allowed at low speeds. For example, even when a preceding vehicle is lost, a feeling of acceleration can be obtained and a curved road can be obtained. Hunting, such as the start of acceleration as soon as the vehicle escapes, can be effectively prevented.

[0035]

As described above, according to the vehicle traveling control device of the present invention, while ensuring the safety of traveling on a curved road, it is possible to further match the driving feeling of the driver and prevent hunting. Can

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a laser radar according to the embodiment.

FIG. 3 is an explanatory diagram of a scanning range of the laser according to the embodiment.

FIG. 4 is an explanatory view of an arrangement in the vicinity of a steering according to the embodiment;

FIG. 5 is an enlarged view of the cruise control switch of the embodiment.

FIG. 6 is an enlarged view of an inter-vehicle time switch according to the embodiment;

FIG. 7 is an explanatory diagram of a display according to the embodiment.

FIG. 8 is an overall processing flowchart of the embodiment.

FIG. 9 is a flowchart of engine output control according to the embodiment.

FIG. 10 is an explanatory diagram illustrating a control mode according to the embodiment.

FIG. 11 is a flowchart of a target acceleration calculation process according to the embodiment.

FIG. 12 is a graph showing a map of a lateral acceleration and a target acceleration upper limit guard value according to the embodiment;

[Explanation of symbols]

10 laser radar, 12 vehicle control ECU, 14 engine ECU, 16 ECT mode switch, 18 cruise control switch, 20 stop lamp switch, 22 vehicle speed sensor, 24 electronic throttle actuator, 26 ECT solenoid, 28 VSC-E
CU, 30 steering sensor, 32 alarm buzzer,
34 body multiplex communication, 36 tail lamp switch,
38 wiper switch, 40 display, 44 inter-vehicle time switch.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuyuki Furui 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (72) Inventor Yasuhiko 1-1-1-1 Showacho, Kariya City, Aichi Prefecture DENSO Corporation (72) Inventor Eiji Teramura 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation

Claims (3)

[Claims] 1. A vehicle travel control device that performs constant acceleration control to set own vehicle speed to a predetermined target value, comprising: a control unit that determines an upper limit value of a target acceleration in the constant acceleration control based on a curve curvature and own vehicle speed. A vehicle travel control device comprising: 2. A vehicle travel control device comprising: a radar for recognizing a preceding vehicle; and control means for controlling an acceleration of the own vehicle based on an output from the radar. And determining an upper limit of the target acceleration. 3. The control means performs constant acceleration control so as to set the own vehicle speed to a target vehicle speed when the preceding vehicle is not detected by the radar, and sets a constant acceleration by the target acceleration when the preceding vehicle is detected by the radar. The vehicle travel control device according to claim 2, wherein the control is performed.