JPH0491333A - Driving controller of vehicle - Google Patents

Abstract

PURPOSE:To gradually and smoothly perform transfer to respective control conditions and prevent feeling of unnecessary unfitness and anxiety by gradually decreasing control gain in each control when a condition under which vehicle speed control is performed is switched to the condition under which control of distance between vehicles is performed. CONSTITUTION:A vehicle speed is detected a means A, and a distance between vehicles is detected by a means B, and the vehicle speed is adjusted by a means C. A target vehicle speed is set by a means D based on the detected vehicle speed at a specified point of time, and also a proper distance between vehicles is set by a means E. The means C is further controlled by a means F so that the vehicle speed may be equalized to the target vehicle speed, and the means C is controlled by a means G so that the distance between vehicles may be equalized to the proper distance between vehicles. When the distance between vehicles is set to a specified value or less, switching from vehicle speed control to the control of distance between vehicles is carried out by means H, and at least one of control gains in respective controls is gradually changed by a means I at the time of the switching.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides vehicle speed control for causing a vehicle to maintain a predetermined traveling speed in accordance with the traveling environment of the vehicle;
The present invention relates to a vehicle travel control device that performs inter-vehicle distance control that causes a vehicle to maintain a predetermined inter-vehicle distance from a vehicle traveling in front.

(Prior Art) When a vehicle is running, a target running speed is set based on the running speed at a selected point in time.
It is known that the vehicle speed control is then performed to automatically maintain the set target travel speed. Such vehicle speed control is performed by a constant speed traveling device equipped on the vehicle, but in such a constant speed traveling device, as shown in Japanese Patent Publication No. 55-46495, for example, the vehicle speed setting is The target traveling speed is set as the target traveling speed, which is the detected output from the vehicle speed sensor at the time when the switch is operated, and the vehicle speed is set according to the difference between the target traveling speed and the detected output from the vehicle speed sensor. A motor that adjusts the opening of a throttle valve located in the intake passage of the engine is activated, thereby placing the vehicle in a running state that maintains a running speed corresponding to the target running speed. .

As mentioned above, in a constant speed driving system that performs vehicle speed control that causes the vehicle to maintain a driving state that maintains a driving speed corresponding to a target driving speed, in addition to vehicle speed control, under predetermined conditions, A vehicle has been proposed that performs inter-vehicle distance control that causes a vehicle in the vehicle to adopt a running state in which a predetermined inter-vehicle distance is automatically maintained between the vehicle and the vehicle traveling in front.

In such inter-vehicle distance control, while the vehicle is running, the inter-vehicle distance to the preceding vehicle is preset, which is detected by an inter-vehicle distance sensor configured using, for example, an ultrasonic transmitter/receiver device installed in the vehicle. If the distance is below the predetermined control boundary distance, the appropriate following distance is set based on the traveling speed of the vehicle detected by the vehicle speed sensor at that time, and the appropriate following distance and the detection output from the following distance sensor are calculated. A motor that adjusts the opening of the throttle valve in the engine is operated according to the difference in the following distance, so that the vehicle corresponds to the appropriate following distance from the vehicle traveling in front. The vehicle will be placed in a driving state that maintains the following distance.

When the above-mentioned vehicle speed control and inter-vehicle distance control are performed by a constant speed traveling device installed in the vehicle,
When the distance between the vehicle and the vehicle in front, as detected by the distance sensor installed in the vehicle, exceeds a preset control boundary distance, the vehicle speed is controlled to allow the vehicle to travel at a target speed. When the vehicle is in a driving state where the vehicle speed is maintained, and the following distance detected by the following distance sensor becomes equal to or less than the preset control boundary distance, the following distance control is changed from the state in which vehicle speed control is performed. The vehicle is switched to a state in which the vehicle speed is controlled, and the vehicle is placed in a driving state in which the vehicle maintains a distance corresponding to the appropriate vehicle distance between itself and the vehicle traveling in front by the vehicle speed control. As a result, a situation in which the inter-vehicle distance from the vehicle to the vehicle traveling ahead becomes too small can be avoided.

(Problem to be Solved by the Invention) In a vehicle equipped with a constant speed traveling device that performs vehicle speed control and inter-vehicle distance control as described above, while vehicle speed control is being performed, the following distance sensor When the inter-vehicle distance from the detected vehicle to the vehicle traveling ahead becomes less than or equal to the predetermined control boundary distance, and the state in which vehicle speed control is performed is switched to the state in which inter-vehicle distance control is performed, the control boundary distance and If the difference between the driving speed detected by the vehicle speed sensor and the appropriate inter-vehicle distance set based on the vehicle speed sensor is relatively large, the following distance detected by the inter-vehicle distance sensor is quickly set based on the driving condition. The vehicle distance is controlled to match the appropriate inter-vehicle distance. As a result, the vehicle accelerates from the time when the state in which vehicle speed control is performed to the state in which inter-vehicle distance control is performed until the time when the inter-vehicle distance to the vehicle traveling in front reaches the appropriate inter-vehicle distance. , the occupants of the vehicle may notice that the vehicle is accelerating toward the vehicle in front of them, causing unnecessary discomfort.
Alternatively, there is the inconvenience of feeling uneasy.

In view of the above, the present invention provides vehicle speed control that automatically causes a vehicle to maintain a traveling speed corresponding to a target traveling speed, and under predetermined conditions, causes the vehicle to automatically maintain a traveling state that maintains a traveling speed corresponding to a target traveling speed. Inter-vehicle distance control automatically maintains the following distance corresponding to the appropriate inter-vehicle distance between vehicles. When the distance falls below a predetermined control boundary distance and the state in which vehicle speed control is performed is switched to the state in which inter-vehicle distance control is performed, the difference between the control boundary distance and the appropriate following distance is relatively large. Even in such cases, it is now possible to avoid a situation where the occupants of the vehicle become aware that the vehicle is accelerating towards the vehicle traveling in front of them and feel unnecessary discomfort or anxiety. The purpose is to provide a vehicle running control device.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the vehicle running control device according to the present invention, as shown in the basic configuration in FIG. , an inter-vehicle distance control means for detecting the inter-vehicle distance from the vehicle to the vehicle traveling ahead; a vehicle speed adjustment means for adjusting the traveling speed of the vehicle; and a target traveling speed based on the traveling speed detected by the vehicle speed control means at a specific time. a target vehicle speed setting means for setting a target vehicle speed, an appropriate following distance setting means for setting an appropriate following distance from the vehicle to a vehicle traveling in front according to the traveling speed detected by the vehicle speed control means at a specific time; a vehicle speed control means for controlling the vehicle speed adjusting means to cause the vehicle to adopt a traveling state in which the traveling speed detected by the means coincides with a target traveling speed; An inter-vehicle distance control means that controls the vehicle speed adjustment means to make the vehicle adopt a running state that corresponds to an appropriate inter-vehicle distance to the vehicle traveling ahead, and a first state in which the vehicle speed adjustment means is controlled by the vehicle speed control means. When the inter-vehicle distance detected by the inter-vehicle distance control means becomes equal to or less than a predetermined value, the first state is switched to a second state in which the vehicle speed adjustment means is controlled by the inter-vehicle distance control means. A control state switching means is provided, and in addition, upon switching from the first state to the second state by the control state switching means,
A gain changing device is provided for gradually changing at least one of a control gain in the control of the vehicle speed adjusting device by the vehicle speed control device and a control gain in the control of the vehicle speed adjusting device by the inter-vehicle distance control device.

(Function) In the vehicle travel control device according to the present invention configured as described above, the vehicle speed control means controls the vehicle so that the travel speed detected by the vehicle speed control means matches the target travel speed. From the first state in which the vehicle speed adjustment means is controlled to cause the vehicle to take a running state, the following distance control means determines whether the following distance detected by the following distance control means is an appropriate following distance from the vehicle to the vehicle traveling in front. When the control state switching means switches the vehicle speed adjusting means to the second state in which the vehicle speed adjusting means is controlled so as to adopt a driving state that coincides with At least one of the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means and the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means is gradually changed, for example, the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means is gradually changed. At the same time, the control gain in the control of the vehicle speed adjustment means by the inter-vehicle distance control means is gradually increased. Therefore, when switching from the first state to the second state, the transition from a state in which the vehicle speed control means controls the vehicle speed adjustment means to a state in which the vehicle speed adjustment means is controlled by the inter-vehicle distance control means gradually occurs. And it will be carried out smoothly.

As a result, when switching from the first state to the second state, the acceleration of the vehicle toward the vehicle traveling ahead is suppressed, and the occupants of the vehicle do not recognize that the vehicle is accelerating toward the vehicle traveling ahead. This will avoid a situation where the patient would feel unnecessary discomfort or anxiety.

(Embodiment) FIG. 2 shows an example of a vehicle travel control device according to the present invention together with a power plant installed in a vehicle to which the device is applied.

The power plant shown in FIG. 2 is composed of an engine (1) and an automatic transmission 2, and the engine (1) has a throttle valve 5, which is driven by an actuator 4, arranged in its intake vent rN3. . The throttle valve 5 is driven by the actuator 4 to change its opening degree, and thereby the engine 1
The amount of air taken into the plurality of cylinders is adjusted.

Further, the automatic transmission 2 is configured to include a torque converter and a multi-gear type transmission mechanism, is connected to the engine 1, and is operated according to the hydraulic pressure supplied from the hydraulic circuit section 7. There is. The torque generated by the engine (2) is transmitted to the drive wheels 9 via the automatic transmission 2 and a wheel drive system including a propeller shaft 8 connected to the output shaft of the automatic transmission 2, thereby driving the drive wheels 9 into rotation. Then, a vehicle (hereinafter referred to as vehicle AT) equipped with a power plant constituted by an engine 1 and an automatic transmission 2 is driven. The torque generated by the engine 1 is changed according to the opening degree of the throttle valve 5, and therefore, the torque generated by the engine 1 is changed according to the opening degree of the throttle valve 5.
The running state of the vehicle AT is changed according to the opening degree of the throttle valve 5, and the throttle valve 5 forms a vehicle speed adjusting means for adjusting the running speed of the vehicle AT.

For the drive wheels 9, a detection output signal SV is sent to detect the rotation speed of the drive wheels 9 and detect the running speed of the vehicle AT;
A vehicle speed sensor 10 is provided that sends the speed to a control unit 50.

The control unit 50 constitutes a part of the vehicle travel control device according to the present invention, and includes a vehicle speed control main switch 11 provided near the driver's seat in the vehicle AT, a vehicle speed setting switch 13, and a vehicle speed control switch 13 provided in the vehicle AT. A vehicle speed control release switch 15 that is turned on when a brake pedal, an accelerator pedal, or the like is depressed is connected. In addition to the detection output signal SV obtained from the vehicle speed sensor IO, the control unit 50 also includes, for example, an ultrasonic transmitting/receiving device, and outputs a detection output signal SV obtained from the inter-vehicle distance sensor 20 disposed at the front end of the vehicle ATO. , from vehicle AT to vehicle A
A detection output signal SS detecting the following distance to the vehicle traveling ahead with respect to T, a detection output signal SA detecting the amount of depression of the accelerator pedal obtained from the accelerator opening sensor 21 provided in relation to the S guard pedal, and an automatic detection output signal SA Transmission 2
A group of detection output signals SX is supplied that detects the operating state of the engine 1 required to perform a speed change operation.

Then, the control unit 50 selectively supplies various automatic transmission control signals ST formed based on the detection output signal group SX to the hydraulic circuit section 7, thereby controlling the automatic transmission 2.
A plurality of frictional engagement elements such as brakes and clutches built into the transmission mechanism of the automatic transmission 2 are engaged or released to control the gear change operation of the automatic transmission 2. The control unit 50 also includes a vehicle speed control main switch 11. Based on the operating states of the vehicle speed setting switch 13 and the vehicle speed control release switch 15 and the detection output signals SV and SS, the vehicle AT
Vehicle speed control is selectively performed to cause the vehicle AT to maintain a predetermined traveling speed, and inter-vehicle distance control is made to cause the vehicle AT to maintain a predetermined inter-vehicle distance from the preceding vehicle. Furthermore, the control B unit 50 stores in its built-in memory a distance within the range of the inter-vehicle distance from the vehicle AT to the vehicle traveling in front that can be accurately detected by the inter-vehicle distance sensor 20, for example, a control boundary distance of 40 m. is said to have been memorized.

Under such circumstances, if the vehicle speed control main switch 11 is not turned on, the control unit 50 does not perform the above-mentioned vehicle speed control or inter-vehicle distance control, but controls the vehicle AT according to the amount of depression of the accelerator pedal. In order to maintain a running state, normal throttle opening control is performed to control the opening of the throttle valve 5 according to the amount of depression of the accelerator pedal. In such normal throttle opening control, the control unit 50 generates a drive control signal CA corresponding to the amount of depression of the accelerator pedal in response to the detection output signal SA. is supplied to the actuator 4, and the actuator 4 operates the throttle valve 5 to take an opening degree corresponding to the drive control signal CA.

On the other hand, when the vehicle speed control main switch 11 is turned on (vehicle speed control release switch 15 is turned off), the control unit 50 normally controls the throttle opening until the vehicle speed setting switch 13 is turned on. However, when the vehicle speed setting switch 13 is turned on, the inter-vehicle distance at which the detection output signal SS is generated is, for example, 4.
It is checked whether it is greater than or less than the control boundary distance which is 0 m, and if the inter-vehicle distance detected by the detection output signal SS is greater than the control boundary distance, vehicle speed control is performed. In the vehicle speed control by the control unit 50, a target traveling speed is set based on the detected traveling speed obtained at the time when the vehicle speed setting switch 13 is turned on. written to memory. Then, a drive control signal CA is generated according to the difference between the stored target traveling speed and the traveling speed at which the detection output signal S obtained from the vehicle speed sensor 10 is detected.
It is supplied to the actuator 4, and the actuator 4
control is performed. Thereby, the throttle valve 50 opening degree is adjusted by the actuator 4 so that the actual traveling speed of the vehicle AT corresponds to the stored target traveling speed, and the vehicle AT travels at a traveling speed corresponding to the target traveling speed. The vehicle is placed in a running state that maintains the following conditions. Further, when the vehicle AT is in a running state in which the vehicle AT maintains a running speed corresponding to the target running speed in this manner, and the vehicle speed control release switch 15 is turned on, the vehicle speed control state is released.

The control unit 50 also includes a vehicle speed control main switch 1
1 is on (vehicle speed control release switch 15 is off)
Under these conditions, when the vehicle speed setting switch 13 is turned on, if the inter-vehicle distance detected by the detection output signal SS is less than the control boundary distance, which is, for example, 40 m, inter-vehicle distance control is performed. In the inter-vehicle distance control performed by the control unit 50 in such a case, the detection output signal s V is used to determine the appropriate inter-vehicle distance on the front side of the vehicle AT based on the traveling speed at which the detection output signal s V is generated at the time when the vehicle speed setting switch 13 is turned on. A distance is set, and a drive control signal CA corresponding to the difference between the set appropriate inter-vehicle distance and the actual inter-vehicle distance generated by the detection output signal SS is formed, and is supplied to the actuator 4 to control the actuator 4. Control takes place. As a result, the opening degree of the throttle valve 5 is adjusted by the actuator 4 so as to cause the vehicle AT to travel such that the following distance to the vehicle traveling ahead corresponds to the appropriate distance, and the vehicle AT is adjusted to the position where the vehicle AT is traveling in front of the vehicle. During this period, the vehicle is placed in a driving state in which the following distance corresponding to the appropriate following distance is maintained. In this manner, when the vehicle speed control release switch I5 is turned on while the vehicle AT is in a running state in which the vehicle AT maintains a distance corresponding to the appropriate distance between the vehicle and the vehicle traveling ahead, the vehicle speed control is controlled. The condition is canceled.

Furthermore, while controlling the vehicle speed as described above, when the inter-vehicle distance at which the detection output signal SS occurs becomes equal to or less than the control boundary distance, which is, for example, 40 m, the control unit 50 performs the following operations: The state in which vehicle speed control is performed is switched to the state in which inter-vehicle distance control is performed as described above. When switching from the vehicle speed control state to the inter-vehicle distance control state, the control gain in the control using the drive control signal CA for the actuator 4 as the vehicle speed control is gradually reduced, and the inter-vehicle distance control state is changed. Drive control signal CA for actuator 4
The control gain in the control is gradually increased. Specifically, if the control gain in the control using the drive control signal CA for the actuator 4 as vehicle speed control is Gv, and the control gain in the control using the drive control signal CA for the actuator 4 as inter-vehicle distance control is Gd, for example, , as shown in FIG. 3 (vertical axis: gain G, horizontal axis: time t), during the period Ta from time point 11 to time point L2 when switching from the state of performing vehicle speed control to the state of performing inter-vehicle distance control, the control The gain Gv decreases linearly from 4riGl to O, and the control gain Gd decreases from O to the value G.
It should increase linearly up to 1. In addition,
In such a case, before the period Ta, the control gain GV takes the value G1 and the control gain Cd takes the value G1, and after the period Ta, the control gain Gv takes the value G1 and the control gain Gv takes the value G1.

By doing this, when switching from a state in which vehicle speed control is performed to a state in which inter-vehicle distance control is performed, the drive control signal C to the actuator 4 as vehicle speed control is used.
For example, the control with A gradually stops being performed within a predetermined period of time Ta, and at the same time,
Control of the actuator 4 using the drive control signal CA as inter-vehicle distance control is gradually performed within a predetermined period, for example, a period Ta. Therefore, switching from vehicle speed control to inter-vehicle distance control is performed smoothly.
When the vehicle speed control is switched from the state where vehicle speed control is performed to the state where vehicle following distance control is performed, the appropriate following distance determined based on the control boundary distance and the following distance control is determined. Even if the difference between the two vehicles is relatively large, the vehicle AT is forced to accelerate toward the vehicle in front in order to match the following distance to the appropriate distance due to the detection output signal SS. This prevents a situation in which the occupant of the vehicle AT recognizes that the vehicle AT is accelerating toward the vehicle running ahead and feels unnecessary discomfort or anxiety.

The control unit 1-50 that performs the above-mentioned operations is configured using, for example, a microcomputer. This will be explained with reference to the flowchart in FIG.

In the flowchart shown in FIG. 4, after the start, in step 60, the detection output signals SV and SS are
In the following step 61, it is determined whether the vehicle speed control main switch 11 is in the on state. If the vehicle speed control main switch 11 is in the off state, the process returns to step 60 and the vehicle speed control main switch 11 is in the on state. If so, in step 62 it is determined whether the vehicle speed control release switch 15 is in the on state. Then, when the vehicle speed control release switch 5 is in the on state, the process returns to step 60, and when the vehicle speed control release switch 15 is in the off state, it is determined in step 63 whether or not the vehicle speed setting switch 13 is in the on state. . As a result, when the vehicle speed setting switch 13 is in the off state, the process returns to step 60, and when the vehicle speed setting switch 13 is in the on state, the process returns to step 64.
In step 65, when the detection output signal Sv is not detected, the traveling speed of the vehicle AT is set as the target traveling speed VT, and the set target traveling speed VT is stored in the built-in memory.
Proceed to.

In step 65, the detection output signal SS is determined to determine whether the inter-vehicle road N (actual inter-vehicle distance) DS from the vehicle AT to the vehicle traveling ahead is less than 40 m, which is the control boundary distance stored in advance in the built-in memory. If the actual inter-vehicle distance DS is greater than 40 m, it is determined in step 66 whether the inter-vehicle distance flag Fn is 1 or not. As a result, when the inter-vehicle distance flag F7 is O, in step 67 the inter-vehicle distance flags F and l are set to 1.
If the inter-vehicle distance flag F7 is 1, the process directly proceeds to step 68. In step 68, the target traveling speed VT stored in step 64 and the detected output signal SV are determined by the vehicle A.
Calculate the difference VQ between the traveling speed of T (actual traveling speed) VS,
In subsequent step 69, control gain Gv for vehicle speed control is set to value G1. Then, in step 70, the difference VQ calculated in step 68 and step 6
Based on the control gain Gv set to the value G1 in step 9,
A control drive signal CA is formed and sent to the actuator 4, and the process returns to step 60.

Furthermore, as a result of the determination in step 65, the actual inter-vehicle distance D
When S is 40 m or less, it is determined in step 71 whether the inter-vehicle distance flag Fn is 1, and when the inter-vehicle distance flag Fn is 1, it is determined in step 72.
In this step, the inter-vehicle distance flag F9 is set to 0 and the process proceeds to step 73, and when the inter-vehicle distance flags F and l are 0, the process directly proceeds to step 73. Step 73
In step 74, it is determined whether the inter-vehicle distance flag F□1 was 1 in the previous cycle in this flowchart, and if the inter-vehicle distance flag F□1 in the previous cycle was 1, the timer is set in step 74. It is determined whether or not the operation of the timer has started, and if the operation of the timer has not started, the operation of the timer is started in step 75, and then the process proceeds to step 76; , proceed directly to step 76. In step 76, step 64
The difference VQ between the target traveling speed VT set in and the actual traveling speed ■S at which the detection output signal SV occurs is calculated, and in the subsequent step 77, the control gain Gv in vehicle speed control is calculated as follows.
As seen in the period Ta shown in FIG. 3, it is set to take a value that decreases linearly from the value G1 to 0. Then, in step 78, step 76
The control drive signal CAI is generated based on the difference VQ calculated in step 77 and the control gain Gv, which is set to take a value that decreases linearly.

Subsequently, in step 79, the appropriate inter-vehicle distance DK to the vehicle running ahead is set according to the actual traveling speed VS at which the detection output signal S■ is detected, and in step 80, the appropriate inter-vehicle distance DK set in step 79 is set. The difference DQ between the detected output signal SS and the actual inter-vehicle distance DS is calculated, and in the subsequent step 81, the control gain Gd in the inter-vehicle distance control is changed from 0 to 0 as seen in the period Ta shown in FIG. It is set to take a value that increases linearly up to the value G1. Then, in step 82,
A control drive signal CA2 is generated based on the difference DQ calculated in step 80 and the control gain Gd set as a value that increases linearly in step 81.

Then, in step 83, the control drive signal CAL formed in step 78 and the control drive signal CA2 formed in step 82 are summed to form a control drive signal CA, and in step 84, the control drive signal CA formed in step 83 is summed. The control drive signal CA is sent to the actuator 4, and the process returns to step 60.

On the other hand, if the result of the judgment in step 73 is that the inter-vehicle distance flag F7-1 one cycle ago is 0,
In step 85, it is determined whether a period Ta as shown in FIG. 3 has elapsed after the timer started operating in step 75.

Then, if the period Ta has elapsed, step 8
In step 6, it is determined whether or not the operation of the timer has been stopped, and if the operation of the timer has not been stopped, the operation of the timer is stopped in step 87, and then the process proceeds to step 8, and the operation of the timer is also stopped. If so, proceed directly to step 88. Step 88
, the appropriate inter-vehicle distance D set in step 79
The difference DQ between K and the actual inter-vehicle distance DS at which the detection output signal SS occurs is calculated, and in the subsequent step 89, the control gain Gd in inter-vehicle distance control is set to a value G1. Then, in step 90, a control drive signal CA is formed based on the difference DQ calculated in step 88 and the control gain Gd set in step 89, and is sent to the actuator 4, and the process returns to step 60.

Further, as a result of the determination in step 85, if the period Ta has not elapsed, the process proceeds to step 76, and each step after step 76 is executed as described above.

In the above example, when switching from a state where vehicle speed control is performed to a state where inter-vehicle distance control is performed, the control gain Gv in the control using the drive control signal CA for the actuator 4 as vehicle speed control is gradually reduced, The control gain Gd in the control using the drive control signal CA for the actuator 4 as inter-vehicle distance control is gradually increased, but the control when switching from the state in which vehicle speed control is performed to the state in which inter-vehicle distance control is performed is As a variation mode of the gains Gv and Gd that is different from the above example, the control gain Gv may be drastically reduced to 0, and the control gain Gd may be gradually increased. Specifically, the control gain is expressed as Gv, for example, when switching from a state where vehicle speed control is performed to a state where inter-vehicle distance control is performed, as shown in FIG. At time tl, the control gain Gd is suddenly decreased to O, and as shown in FIG. , so that it increases linearly from 0 to the value G1. In this case as well, before the period Ta, the control gain Gv takes the value Gl and the control gain Gd is 0, and after the period Ta, the control gain GV becomes O.
The control gain Cd takes the value G1.

An example of a program executed by the control unit 50 when performing vehicle speed control and inter-vehicle distance control each time the control gains Gv and Gd change is as shown in the flowchart of FIG. be done.

In the flowchart shown in FIG. 6, steps corresponding to the steps in the flowchart shown in FIG. 4 are shown with the same reference numerals as in FIG. 4, and duplicate explanations thereof will be omitted. Ru.

In the flowchart of FIG. 6, after the difference VQ between the target traveling speed VT and the actual traveling speed ■S is calculated in step 76, the control gain Gv in vehicle speed control is calculated in step 91 as shown in FIG. 0, as seen at time L1 at the beginning of the period Ta shown. Subsequently, in step 92, the detection output signal SV sets an appropriate inter-vehicle distance DK to the preceding vehicle according to the actual traveling speed VS, and in step 93, the appropriate inter-vehicle distance DK set in step 92 is detected. Output signal SS
In step 94, the control gain Gd in the distance pressure separation control is calculated in a straight line from 0 to the value G1, as seen in the period Ta shown in FIG. Set as a value that increases over time. Then, in step 95, the difference DQ calculated in step 93 and the control gain Gd set as a value that increases linearly in step 94.
A control drive signal CA is formed based on this, and it is sent to the actuator 4, and the process returns to step 60.

(Effects of the Invention) As is clear from the above description, the vehicle running control device according to the present invention has a vehicle speed control system that automatically maintains a running state in which the vehicle maintains a running speed corresponding to a target running speed. Under predetermined conditions, inter-vehicle distance control is performed that automatically causes the vehicle to take a running state that maintains a inter-vehicle pressure H1 corresponding to an appropriate inter-vehicle distance between the vehicle and the vehicle traveling in front;
When vehicle speed control is being performed, the following distance between the vehicle and the vehicle traveling ahead becomes less than a predetermined control boundary force separation, and the state in which vehicle speed control is performed is switched to the state in which following distance control is performed. The gain changing means gradually changes at least one of the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means and the control gain in the control of the vehicle speed adjustment means by the inter-vehicle distance control means. For example, the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means is gradually reduced, and the control gain in the control of the vehicle speed adjustment means by the inter-vehicle distance control means is gradually increased. In switching from a state in which inter-vehicle distance control is performed to a state in which inter-vehicle distance control is performed, the state in which the vehicle speed control means controls the vehicle speed adjustment means gradually shifts to a state in which the inter-vehicle distance control means controls the vehicle speed adjustment means. And it will be carried out smoothly. As a result, when switching from a state in which vehicle speed control is performed to a state in which inter-vehicle distance control is performed, acceleration of the vehicle toward the vehicle traveling ahead can be suppressed, and the occupants of the vehicle can be prevented from accelerating toward the vehicle traveling ahead of the vehicle. This makes it possible to avoid a situation where the driver feels unnecessary discomfort or anxiety due to recognition of accelerated driving.

[Brief explanation of the drawing]

Fig. 1 is a basic configuration diagram showing a vehicle stray running control device according to the present invention in accordance with the claims, and Fig. 2 shows an example of the vehicle running control device according to the present invention. A schematic configuration diagram shown together with the plant, Figure 3 is the second
FIG. 4 is a characteristic diagram used to explain the operation of the example shown in FIG. 4, and FIG. 5 is a characteristic diagram for explaining another example of the control mode in the example shown in FIG. 2, and FIG. 6 is a microcomputer used in the control unit in the example shown in FIG. 2. FIG. 5 is a flowchart showing an example of a program executed when taking another control mode explained using the characteristic diagram of FIG. 5; FIG. In the figure, 4 is an actuator, 5 is a throttle valve, 10 is a vehicle speed sensor, 11 is a vehicle speed control main switch, 13 is a vehicle speed setting switch, 15 is a vehicle speed control release switch, 20 is an inter-vehicle distance sensor, and 50 is a control unit.

Claims (1)

[Scope of Claims] 1. Vehicle speed detection means for detecting the running speed of the vehicle, inter-vehicle distance detection means for detecting the inter-vehicle distance from the vehicle to the vehicle traveling ahead, and vehicle speed adjustment means for adjusting the running speed of the vehicle. , target vehicle speed setting means for setting a target travel speed based on the travel speed detected by the vehicle speed detection means at a specific time; and target vehicle speed setting means for setting a target travel speed based on the travel speed detected by the vehicle speed detection means at a particular time; Appropriate inter-vehicle distance setting means for setting an appropriate inter-vehicle distance to a vehicle traveling ahead; a vehicle speed control means for controlling the vehicle speed adjustment means; and a control for the vehicle speed adjustment means to cause the vehicle to adopt a running state in which the inter-vehicle distance detected by the inter-vehicle distance detection means coincides with the appropriate inter-vehicle distance. and when the following distance detected by the following distance detecting means becomes less than a predetermined value under a first state in which the vehicle speed adjusting means is controlled by the vehicle speed controlling means,
control state switching means for switching from the first state to a second state in which the vehicle speed adjusting means is controlled by the inter-vehicle distance control means; When switching to state 2, a gain change that gradually changes at least one of a control gain in the control of the vehicle speed adjustment means by the vehicle speed control means and a control gain in the control of the vehicle speed adjustment means by the inter-vehicle distance control means. A vehicle running control device comprising: means. 2. The gain changing means, upon switching from the first state to the second state by the control state switching means,
A claim characterized in that the control gain in the control of the vehicle speed adjustment means by the vehicle speed control means is rapidly reduced, and the control gain in the control of the vehicle speed adjustment means by the inter-vehicle distance control means is gradually increased. Item 1. The vehicle running control device according to item 1.