JPH04193631A - Controlling device for safe distance - Google Patents

Abstract

PURPOSE:To make a vehicle run continuously so as to make it comfortable to ride in the vehicle and improve consumption by controlling the vehicle at a speed corresponding to the distance between the vehicle and a vehicle ahead if the vehicle ahead is in an intermittent running condition wherein it repeatedly starts and stops as in a traffic jam. CONSTITUTION:The travel speed of a vehicle is detected by a means A. The distance between the vehicle and a vehicle ahead is detected by a means B. A means C judges according to the vehicle speed and the distance detected whether or not the vehicle ahead continues to run over a predeteremined distance without stopping. When the vehicle ahead is judged to be running continuously, a speed at which to maintain a proper distance between the two vehicles is calculated relative to the speed of the vehicle ahead by a means D, while when the vehicle ahead is judged to be in an intermittent running condition wherein it repeatedly starts and stops a speed corresponding to the distance between the two vehicles is calculated by the means D. Thereafter, the speed of the vehicle is controlled to the calculated value by a means E.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inter-vehicle distance control device. In particular, the present invention relates to an inter-vehicle distance control device during traffic jams.

[Conventional technology]

Examples of conventional inter-vehicle distance control devices include those shown in Figures 6 and 7.
There were some as shown in Figure and Figure 8.

(Japanese Unexamined Patent Publication No. 6O-163732) FIG. 6 is a diagram showing a functional block diagram of the inter-vehicle distance control device. Shift 11B to the drive engine and these controls
In a vehicle equipped with a device C, a following distance detecting means for detecting the traveling speed of the vehicle, a first data storage means E storing data to be compared with the output value thereof, and a first data storing means E for measuring the following distance to the vehicle in front. A second data storage means G that stores data to be compared with the output value of the inter-vehicle distance detection means Q, a timer means H that measures time, and an appropriate inter-vehicle distance signal for the output value of the vehicle speed detection means. An output means I for outputting , a throttle valve actuator for opening and closing a throttle valve J, and an exhaust pipe valve actuator N for opening and closing an exhaust pipe valve M for adjusting the amount of exhaust gas discharged are provided.

For example, when the detected vehicle speed is equal to a preset vehicle speed and the detected inter-vehicle distance is longer than the preset inter-vehicle distance, the throttle valve actuator K drives the throttle valve J in the opening direction. , the exhaust pipe valve actuator N opens the exhaust pipe valve M, and each control signal Sk, Sn, Sb is outputted from the control device C singly or simultaneously, such as to issue an acceleration command to the gear shift 11B, thereby adjusting the inter-vehicle distance. The driving force of the vehicle is increased so that the following distance matches a preset inter-vehicle distance.

FIG. 7 is an explanatory diagram of the inter-vehicle distance detection means. Reference numeral 1 denotes a vehicle equipped with an inter-vehicle distance control device, and an ultrasonic microphone 3 for transmitting and receiving ultrasonic waves is installed at the front of the vehicle body. This ultrasonic microphone 3 generates an ultrasonic wave by the ultrasonic microphone drive vibration outputted from the control unit 100, receives the ultrasonic wave reflected by the vehicle 2 traveling in front, and transmits the received signal to the control unit 100. 100
Output to. The control unit 100 calculates the inter-vehicle distance between the vehicle 1 and the preceding vehicle 2 based on the time difference between the time when the ultrasonic microphone 3 generates the ultrasonic wave and the time when the reflected wave is received.

FIG. 8 is a diagram showing the configuration of the following distance control system.

Start, run, and stop with ignition switch 4 m1
The output of the drive engine 5 is transmitted from the propeller shaft 8 to the differential gear 9 by selecting a power transmission mode such as parking, forward, reverse, or neutral using the select lever 6. The signal is then transmitted to the left and right rear wheels 101.10R to drive the vehicle.

The accelerator pedal 11 controls the engine output, and the brake pedal 12 controls the front wheels 13L, 13R and the rear wheels 10L, 1.
Controls the driving force of 0R. Furthermore, the parking brake lever 14 increases the braking force when parking the vehicle by i+1IIa.

Control unit 100 is a control device that controls engine 5 and transmission 7 according to signals from various parts. Note that the operation mode changes depending on data from the data input device 215.

It also outputs various data to the display device 16.

Power is input directly from an on-board battery 17 and via a power relay 18 .

[Problems to be Solved by the Invention] However, with such conventional inter-vehicle distance control devices, during normal driving, the vehicle in front of the vehicle is controlled at such a speed as to maintain an appropriate distance from the vehicle in front of the vehicle. Therefore, when the vehicle in front repeatedly starts and stops, such as during traffic jams, the problem arises that the own vehicle also starts and stops repeatedly, resulting in poor ride comfort and poor fuel efficiency. there were.

The present invention was made in view of these conventional problems, and it is an object of the present invention to provide a device that does not impair ride comfort and does not worsen fuel efficiency even when the vehicle in front repeatedly starts and stops. purpose.

[Means to solve the problem]

In the present invention, as shown in FIG. 1, a vehicle speed detection means for detecting the traveling speed of the own vehicle, an inter-vehicle distance detection means for detecting the inter-vehicle distance between the own vehicle and the vehicle traveling ahead, and a Continuous traveling determining means for determining whether or not a vehicle traveling ahead is traveling continuously for a predetermined distance without stopping based on an inter-vehicle distance; When this is determined, the system calculates the speed that maintains an appropriate following distance based on the vehicle speed of the vehicle in front.
In addition, when it is determined that the driving is intermittent, such as repeatedly starting and stopping, the calculation means calculates the speed based on the distance between the vehicle traveling ahead and the own vehicle, and the calculation means uses the calculation means. and speed control means for controlling the speed of the own vehicle to the calculated speed.

[Function] With the above configuration, when it is determined that the vehicle in front is traveling continuously for a predetermined distance without stopping, an appropriate inter-vehicle distance is maintained in relation to the speed of the vehicle in front. It calculates the speed and follows the vehicle in front. Additionally, if it is determined that the vehicle in front of the vehicle is traveling intermittently by repeatedly starting and stopping, the system calculates the speed based on the distance between the vehicle in front of the vehicle and the vehicle in front of the vehicle.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 2 and subsequent figures.

FIG. 2 is a functional block diagram showing the configuration of one embodiment of the following distance control device.

First, the configuration will be explained.

Q is an inter-vehicle distance detection means for detecting the inter-vehicle distance between the vehicle traveling ahead and the own vehicle, and D is a vehicle speed detection means for detecting the vehicle speed of the own vehicle. A storage means P for storing the output value of the vehicle speed detection means and a timer means H for measuring time are provided. The signals output from these are input to the control device and the performance means R, and based on the input signals, it is determined whether the vehicle ahead is traveling continuously, and the output value of the inter-vehicle distance detection means is determined to be an appropriate inter-vehicle distance signal. When the output value differs from the output value of the output means I which outputs R It has become. Further, the drive engine A transmits power via a transmission B.

Next, the action will be explained.

This device first detects the vehicle speed Vo of the host vehicle and the inter-vehicle distance Lt between the host vehicle and the vehicle in front, and then detects the vehicle speed V of the vehicle in front.
Make F shine. Next, it is determined whether the preceding vehicle is running, and if the distance that the preceding vehicle has continued to travel without stopping after starting is greater than or equal to a certain value thi, it is considered to be running continuously. It is judged that Togi did not run continuously for 1M. When it is determined that the vehicle ahead is traveling continuously, the host vehicle sets a target vehicle speed for follow-up travel and starts follow-up travel. When it is determined that the vehicle in front is traveling discontinuously, the distance between the own vehicle and the vehicle in front is detected, and when the value exceeds a certain value th2, the vehicle runs to reduce the distance between the vehicles.

Hereinafter, explanation will be given along the flowchart shown in FIG.

(1), (21) The variables are set. This device starts processing from the stopped state of the own vehicle and the protected vehicle.

In (3), the vehicle speed VF of the preceding vehicle is calculated. First, the inter-vehicle distance detecting means Q measures the inter-vehicle distance Lt between the host vehicle and the vehicle ahead at measurement intervals.

From the first measured distance 1t1 and the second measured distance 1t2, the moving distance F of the vehicle in front is F-j! It becomes t2-j2tt. The speed of the vehicle ahead is faster than the vehicle speed Vo of the own vehicle, as follows: VF = Vo +F/l.

In F judgment 1 of (4), it is judged whether the vehicle ahead is moving or not, and processing is performed according to the judgment. FIG. 4 shows a flowchart of the process.

(4) In -1, a preset threshold value th4 is compared with the moving distance F of the vehicle in front. When the travel distance IF is smaller than the threshold value th4, the vehicle ahead is considered to have stopped, and in (4)-2, the variable S is set to 0, and in (4)-3, the speed data of the vehicle ahead that has been stored so far is Erase. Furthermore, when the moving distance F is greater than the threshold value ti14, it is determined that the vehicle ahead is traveling, and the variable S=S+F is integrated in (4)-4, and the speed of the vehicle ahead is determined in (4)-5. Memorize VF. Through the above processing, the product nose value of the moving distance F after the preceding vehicle once stops becomes S.

In (5), it is determined whether the vehicle ahead is traveling continuously. 10 variables that are determined by comparing the preset threshold thi and the variable S obtained in (4) F judgment 1. When S is greater than the threshold thl, that is, the cumulative distance traveled since the start of driving is If it is larger, it is determined that the vehicle is running continuously, and the process moves to follow-up travel. When the variable S is smaller than thl, that is, when the vehicle in front is not moving, or even if it is moving, it is only a short distance, it is determined that the vehicle is running discontinuously, and the process proceeds to the next step.

First, the discontinuous running process will be explained below.

In (6), the distance Lt between the host vehicle and the vehicle ahead is compared with a preset threshold value th2, and it is determined whether the distance between vehicles needs to be shortened. If it is determined that shortening is necessary, the process returns to (7), and if it is determined that it is not necessary, the process returns to (3).

In (7), the preset speed VS is set to the vehicle's eye I.
Speed control is performed as I medium speed.

In the next process (81, (9)), the same process as the above process (3), (4) is performed.The difference is that the own vehicle is running.

In (10), it is determined whether to continue driving at a constant speed. Comparing the inter-vehicle distance 1-t with a preset threshold value th3, if the inter-vehicle distance Lt is greater than the threshold [1th3], the vehicle continues to drive at a constant speed. After this, (12
), the variable S is again compared with the threshold value th1, and when the variable S is larger than the threshold value th1, that is, when the vehicle in front has traveled continuously for a predetermined distance or more, the process moves to follow-up travel. Furthermore, when the inter-vehicle distance Lt is smaller than the threshold value th3, it is determined that constant speed driving has ended, and the speed Vo of the own vehicle is changed to Q.
lv/h and move on to process (3).

Next, the continuous running process will be explained.

In (13), the variable ENDJ for determining the end of follow-up travel is 0.
shall be.

In (14), the heavy speed F of the vehicle in front that has been memorized so far is
The follow-up vehicle speed VR is determined by reading out each piece of data in each control cycle and setting it as the target vehicle speed. In other words, the driving of the vehicle in front is reproduced with a delay of a certain amount of time and a certain distance.

In (15), the same processing as in (3) above is performed.

In F judgment 2 of (16), it is judged that the vehicle ahead is traveling, and processing is performed according to the judgment. FIG. 5 shows a flowchart of the process. (51-1 compares the travel distance fgF with a preset threshold value th4, and when the travel distance F is smaller than the threshold value th4, it is determined that the vehicle ahead has stopped, and (5) -2 and variable S=O,
(5) In -3, the variable ENOF used to determine the end of the following driving of the host vehicle is set to 1, and it is determined that the vehicle in front ends continuous driving and the own vehicle ends the following driving. When the moving distance F is larger than the threshold th4, the variable S is expressed as (5)-4.
=S+F is performed, and the speed VF of the vehicle ahead is stored in (5L5).

In step (17), a decision is made as to whether to continue the follow-up travel or to end it and move on to constant speed travel processing. The conditions are that the vehicle in front ends continuous travel in F judgment 2 of (16) and the own vehicle ends follow-up travel, and the speed Vo of the own vehicle is the speed V when traveling at a constant speed.
When the conditions of s or less are satisfied, the above (12)
The process returns to step 1 and determines whether to perform follow-up travel processing. At this time, in step (18), the speed data of the preceding vehicle that has been stored so far is erased.

If the condition (11) is not met, the process returns to (14) to determine the next following speed VR and continue the following traveling.

〔effect〕

As described above, according to the present invention, the configuration includes a vehicle speed detecting means for detecting the traveling speed of the own vehicle, an inter-vehicle distance detecting means for detecting the inter-vehicle distance between the own vehicle and the vehicle traveling ahead, a continuous running determination means for determining whether or not a vehicle traveling in front is continuously traveling a predetermined distance based on the vehicle speed and inter-vehicle distance; When this is determined, it calculates the speed that maintains an appropriate following distance based on the vehicle speed of the vehicle in front, and if it is determined that the vehicle is running intermittently, such as repeatedly starting and stopping, the distance between the vehicle and the vehicle traveling in front is calculated. The weight and distance control device has a performance means that calculates the speed based on the distance between the vehicle and the vehicle, and a speed control means that controls the speed of the own vehicle to the speed calculated by the performance means, so When the front J vehicle repeatedly starts and stops, the own vehicle runs continuously by calculating the speed based on the inter-vehicle road 11 between the own vehicle and the front 111ei. This has the effect of providing a comfortable ride and improving fuel efficiency.

[Brief explanation of the drawing]

FIG. 1 is a diagram corresponding to claims of the present invention. FIG. 2 is a functional block diagram showing the configuration of the present invention. FIG. 3 is a diagram showing an overall flowchart of the present invention. FIG. 4 is a diagram showing a flowchart of a portion of the present invention in which the movement of the vehicle ahead is determined and the processing according to the determination is performed. FIG. 5 is a flowchart showing a portion of the present invention that determines the movement of a preceding vehicle during follow-up driving and performs processing according to the determination. FIG. 6 is a functional block diagram showing the configuration of a conventional following distance system m+ table device. FIG. 7 is an explanatory diagram showing an example of inter-vehicle distance detection means used in a conventional inter-vehicle distance control device. FIG. 8 is an overall configuration diagram of an example of a conventional inter-vehicle distance control device. D...Vehicle speed detection means, R...Control device and calculation means, ■...Output means for outputting an appropriate inter-vehicle distance signal, Q
... Inter-vehicle distance detection means. Patent applicant Nissan Motor Co., Ltd. Figure 3 Figure 4 Figure 5: Figure 8

Claims (1)

[Claims] A vehicle speed detection means for detecting the running speed of the own vehicle, a following distance detecting means for detecting the distance between the vehicle running ahead and the own vehicle, and a driving state of the vehicle running ahead from the detected vehicle speed and the following distance. Continuous travel determining means for determining whether or not the vehicle is traveling continuously for a predetermined distance without stopping, and when the continuous travel determining means determines that the vehicle is traveling continuously, the vehicle speed is determined based on the vehicle speed of the vehicle in front. It calculates the speed that maintains an appropriate distance between vehicles, and when it is determined that the vehicle is running intermittently, such as repeatedly starting and stopping, it calculates the speed based on the distance between the vehicle in front and the own vehicle. An inter-vehicle distance control device comprising a calculation means and a speed control means for controlling the speed of the host vehicle to the speed calculated by the calculation means.