KR20080052739A - Controlling apparatus for distance between cars, collision reduction and collision prevention and controlling method thereof - Google Patents

Abstract

A control apparatus for controlling distance between vehicles and reducing and preventing a collision and a control method is provided to secure safety for drivers by controlling the distance between vehicles and reduction and prevention of a collision with one controller in consideration of the road condition or weather condition. A control apparatus for controlling distance between vehicles and reducing and preventing a collision is composed of: a millimeter wave radar sensor(32) detecting whether the preceding vehicle exists or not, and measuring the relative distance to the preceding vehicle and relative speed; a friction force estimating instrument(34) estimating friction force of tires and the road surface; an acceleration sensor(36) measuring the acceleration of the vehicle; a driving characteristic analyzer receiving information from the millimeter wave radar sensor, the friction force estimating instrument, and the acceleration sensor and operation information of a brake, storing the information, and making the driving characteristic of a driver into a parameter by analyzing the information; a brake actuator(22) controlling the operation of the brake; and a control unit(20) receiving the parameter output by analyzing the driving characteristic of a driver, from the driving characteristic analyzer and the driving information of the present vehicle, and calculating and monitoring a collision warning index and time-to-collision on the basis of the driving information of the present vehicle and the transmitted parameters. The control unit controls the brake actuator by calculating target acceleration on the basis of the collision warning index and time-to-collision.

Description

Controlling apparatus for distance between cars, collision reduction and collision prevention and controlling method

1 is a block diagram illustrating an apparatus for controlling vehicle distance, reducing collision, and preventing collision according to an exemplary embodiment of the present invention.

2 is a flowchart illustrating a method for controlling distance between vehicles, reducing collision, and preventing collision according to an exemplary embodiment of the present invention.

3 is a diagram illustrating any one of driving characteristics of a driver stored in a driving characteristic analyzer;

4 is a graph showing the target acceleration against the collision warning index and the reverse collision time.

<Explanation of symbols for the main parts of the drawings>

10: operation start signal generator 20: control unit

22: brake actuator 24: collision warning signal generator

32 millimeter wave radar sensor 34 friction force estimator

36: acceleration sensor 38: driving characteristic analyzer

The present invention relates to inter-vehicle distance control, collision alleviation and collision avoidance control systems, and in particular, inter-vehicle distance control, collision alleviation and collision control, which can be controlled by one controller by integrating the vehicle inter-vehicle control, collision alleviation and impulse prevention control An anti-control device and a method thereof are provided.

While a vehicle provides a lot of convenience for the driver, it has many factors that threaten the driver's safety. Therefore, recent automobiles have evolved to be equipped with technologies for simultaneously promoting the convenience and safety of the driver.

At present, the technologies of automobiles for both driver comfort and safety at the same time include an inter-vehicle distance control system and an impulse alleviation and collision avoidance control system. The inter-vehicle distance control system is equipped with radar sensors or ultrasonic sensors in front of the vehicle to measure the relative distance and relative speed with the counterpart vehicle and maintains the inter-vehicle distance through the brake actuator controller. It is a system that provides a crash warning to the driver through the collision warning controller when the vehicle reaches a set dangerous situation by mounting radar sensors or ultrasonic sensors in front of the vehicle.

However, the inter-vehicle distance control system and the impulse alleviation and collision avoidance control system have a problem of increasing the production cost of the vehicle as each having an independent controller.

In addition, the inter-vehicle distance control system and the impulse alleviation and collision avoidance control system may calculate the optimum inter-vehicle distance by a parameter set by simply using signals detected from radar sensors or ultrasonic sensors without considering driving road environment or weather conditions. In other words, the absolute safety of the driver cannot be guaranteed because the surrounding road environment or weather conditions are not taken into consideration, such as calculating a maximum stopping distance.

Accordingly, it is an object of the present invention to provide a vehicle distance control, collision reduction and collision avoidance control apparatus and a method for controlling vehicle distance control, collision reduction and impulse prevention control with one controller.

In addition, another object of the present invention is to provide a vehicle distance control, collision reduction and collision avoidance control apparatus and method for controlling the vehicle distance and collision reduction and impulse prevention in consideration of a driving road environment or weather conditions. .

In order to achieve the above object, the inter-vehicle distance control and collision reduction and collision prevention control apparatus according to an embodiment of the present invention and the millimeter wave radar sensor for measuring the presence or absence of the preceding vehicle, the relative distance and relative speed with the preceding vehicle and ; A friction force estimator for estimating the friction force between the tire and the road surface; An acceleration sensor measuring acceleration of the vehicle; A driving characteristic analyzer configured to receive information from the millimeter wave radar sensor, the friction force estimator, and the acceleration sensor, store and analyze brake operation information, and to parameterize driving characteristics of a driver; A brake actuator for controlling the operation of the brake; Parameters for analyzing driving characteristics of the driver and driving information of the current vehicle are transmitted from the driving characteristic analyzer, and the collision warning index and the collision time are calculated and monitored based on the driving information of the current vehicle and the transmitted parameters, and the collision is calculated. And a control unit for controlling the brake actuator by calculating a target acceleration based on an alarm index and a back collision time.

The brake actuator reduces the speed of the vehicle or forcibly stops the vehicle according to the calculated target acceleration.

The inter-vehicle distance control, collision reduction and collision avoidance control apparatus may include an operation start signal generator configured to input an operation start signal for turning on the control unit by a driver's selection; Under the control of the controller, a collision warning signal including a display unit for displaying a warning message and a collision warning message for maintaining the distance between the preceding vehicle, and a speaker for generating a warning sound and a collision warning sound for maintaining the distance between the preceding vehicle. It further comprises a generator.

The inter-vehicle distance control, collision reduction and collision avoidance control method according to an embodiment of the present invention measures the presence or absence of a preceding vehicle, a relative distance between the preceding vehicle and a relative speed, estimates a friction force between a tire and a road surface, and accelerates the acceleration of the vehicle. Measuring a first step; A second step of storing information measured and estimated in the first step and brake operation information while driving the vehicle; A third step of parameterizing driving characteristics of the driver by analyzing the information stored in the second step; A fourth step of determining whether an operation start signal by a driver's selection is input; When the operation start signal is input in the fourth step, the collision alarm index W and the reverse collision time (TCC- ¹ ) using the information measured and estimated in the first step and the parameterized information in the third step Calculating a fifth step; Wherein said one said conflict alert index (W) and a reverse impact time calculated in the step 5 ^(-1 TCC) for monitoring and said conflict alert index (W) and a reverse impact time by controlling the target acceleration based on the ^(-1 TCC) Vehicle A sixth step of reducing the speed of the vehicle or stopping the vehicle.

The inter-vehicle distance control and collision reduction and collision avoidance control method may include displaying a warning message and a collision warning message for maintaining the inter-vehicle distance with the preceding vehicle or generating a warning sound and a collision warning sound for maintaining the inter-vehicle distance with the preceding vehicle. It includes more.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram illustrating an apparatus for controlling vehicle distance, collision reducing, and collision preventing according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the inter-vehicle distance control, collision reduction, and collision avoidance control apparatus according to an embodiment of the present invention includes a millimeter wave radar sensor 32 measuring a relative distance and a relative speed with a preceding vehicle, and a tire and a road surface. Information from the friction force estimator 34 for estimating the friction force, the acceleration sensor 36 for measuring the acceleration of the vehicle, the millimeter wave radar sensor 32, the friction force estimator 34 and the acceleration sensor 36, and brake operation A driving characteristic analyzer 38 for parameterizing driving characteristics of a driver by receiving and storing information, and analyzing the information is provided. In addition, the inter-vehicle distance control, collision reduction and collision prevention control device of the present invention is a display unit for displaying a brake actuator 22 for controlling the operation of the brake, a warning message and a collision warning message to maintain the distance between the vehicle and the preceding vehicle A collision warning signal generator 24 including a speaker sound 24b for generating a warning sound for maintaining the distance between the vehicle 24a and the preceding vehicle and a warning sound and a collision warning sound for maintaining the distance between the preceding vehicle; Parameters for analyzing driving characteristics of the driver and driving information of the current vehicle are transmitted from the driving characteristic analyzer 38, and the brake actuator 22 and the collision warning signal are generated based on the driving information of the current vehicle and the transmitted parameters. The control unit 20 for controlling the unit 24, and the operation start scene to which the operation start signal is selected by the driver's selection. And a generator (10).

The millimeter wave radar sensor 32 is mounted at the front of the vehicle and measures the presence or absence of the vehicle in the front lane, the relative speed and the relative distance with the preceding vehicle, and transmits it to the driving characteristic analyzer 38.

The friction force estimator 34 estimates the friction force between the road pavement and the tire and the road surface according to the material of the road pavement or the weather condition, and transmits the frictional force to the driving characteristic analyzer 38.

The acceleration sensor 36 is mounted at the center position of the vehicle to measure the acceleration of the vehicle and transmit it to the driving characteristic analyzer 38.

The driving characteristic analyzer 38 receives and stores information from the millimeter wave radar sensor 32, the friction force estimator 34, and the acceleration sensor 36, and brake operation information. The driving characteristics of various drivers are parameterized, such as the inter-vehicle distance, the available acceleration range of the vehicle, the system delay and the reaction time of the user.

The controller 20 may be configured to calculate driving information of the current vehicle measured by the millimeter wave radar sensor 32, the friction force estimator 34, and the acceleration sensor 36 from the driving characteristic analyzer 38, and the driving characteristic analyzer 38 may include the driving characteristic analyzer 38. The received parameter is transmitted, and the collision acceleration index and inverse time-to-collision time (TTC- ¹ ), etc. are calculated and monitored based on the transmitted information of the current vehicle and the parameters. To reduce the speed of the vehicle or forcibly stop the vehicle through the brake actuator 22, and display a warning message for maintaining the distance between the vehicle and the preceding vehicle through the collision warning signal generator 24 or A warning sound and a collision warning sound are generated to maintain the distance between the vehicle and the vehicle.

The inter-vehicle distance control and the collision-reduction and collision prevention control method using the inter-vehicle distance control and the collision reduction and collision prevention control apparatus according to the embodiment of the present invention will be described with reference to FIG. 2.

2, the inter-vehicle distance control, collision reduction and collision prevention control method according to an embodiment of the present invention measures the presence or absence of a preceding vehicle, the relative distance and relative speed with the preceding vehicle while the vehicle is driving, To estimate the frictional force of the tire and the road surface according to the material or the weather condition, and measure the acceleration of the vehicle (S110). In addition, the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention inputs and stores the information measured and estimated in step S110 and the brake operation information while driving the vehicle to the driving characteristic analyzer (S120). Subsequently, the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention parameterizes the driving characteristic of the driver by analyzing the information input and stored in the driving characteristic analyzer in step S120 (S130). Then, the inter-vehicle distance control and collision reduction and collision avoidance control method according to the present invention determines whether an operation start signal for starting the inter-vehicle distance control and collision reduction and collision avoidance control system is input by the driver (S140). As a result of the determination, when the operation start signal is input, the inter-vehicle distance control, collision reducing, and collision preventing control method according to the present invention is based on the information measured and estimated in step S110 and the parameters of the step S130 and the inverse of the alarm warning index (W). By calculating and monitoring the collision time (TCC- ¹ ), the final acceleration (a _des (t)) is calculated.

The target acceleration (a _des (t)), the collision warning index (W) and the reverse collision time (TTC ^-1 ) of step S150 is calculated through the following process.

The target acceleration a _des (t) is

Where k ₁ and k ₂ are optimal control constants, k ₁ (v _c (t)) and k ₂ (v _c (t)) are optimal control gains.

v _c is the speed of the vehicle, v _p is the speed of the preceding vehicle

c _d is the target distance, c is the current distance,

The optimal control gain k ₁ (v _c (t)), k ₂ (v _c (t)) is

Where u is the acceleration of the vehicle and w is the acceleration of the preceding vehicle

Where c _d -c is the distance error

v _p -v _c is the speed error of the vehicle

        τ is the speed time gap

Calculate using the following performance index.

Where ρ ₁ is a weight for the distance error

ρ ₂ is a weight for the speed error of the vehicle

        γ is a weight for the acceleration error of the vehicle

The inter-vehicle distance control, collision mitigation and anti-collision control method of the present invention is optimized to be more sensitive to the distance error at low speed and more sensitive to the vehicle speed error at high speed by setting weights differently according to the distance, speed and acceleration of the vehicle. Calculate the control gain.

The target inter-vehicle distance c _d is calculated by the following equation.

Where τ _l is a low speed time gap and τ _h is a high speed time gap

c ₀ is the initial distance

v _th is the threshold speed

The time gap is set based on the driving characteristics of the driver stored in the driving characteristic analyzer as shown in FIG. 3.

The target acceleration (a _des (t)) calculated above is

Where a _* (t) =-k ₁ (v _c (t)) · (c _d (t) -c (t))-k ₂ (v _c (t)) · (v _p (t) -v _c (t))

a _max is the maximum acceleration, a _min is the minimum acceleration

k ₁ , k ₂ are the optimal control constants

v _c is the speed of the vehicle, v _p is the speed of the preceding vehicle

c _d is the target distance

The target acceleration a _* (t) calculated above is set so as not to deviate from a certain range. Here, a _max (v _c (t)) and a _min (v _c (t)) are based on the statistical data of the available acceleration for each speed area of the driver in a general situation except the sudden deceleration. In other words, the driver selects the driver's emotional characteristics.

The target acceleration a _des (t) calculated above is reset when the preceding vehicle is far away and when there is no preceding vehicle.

When leading vehicles are far away

Where d _offset is the offset distance

K _s is the speed gain

When the preceding vehicle is located at a distance d _offset or more than the target inter-vehicle distance c _d , the target acceleration is reset as described above. That is, by controlling the vehicle to approach the preceding vehicle gradually by feeding back the error of the value obtained by adding the constant speed (v _offset ) to the speed of the preceding vehicle.

When there is no leading vehicle

Where v _set is the speed _set by the driver

K _ss is driver set speed gain

In addition, the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention calculates the collision alarm index (W) and the reverse collision time (TTC- ¹ ).

In order to calculate the collision warning index (W), first, the minimum safety distance (d _safety ) and the minimum braking distance (d _braking ) are calculated.

Where t _{sys - de} is the system delay

t _{h , min} is the user's minimum response time

a _max is the maximum deceleration of the vehicle

v _c is the speed of the vehicle

v _re is relative speed

The friction coefficient f (μ) of the tire and the road surface is calculated by the following equation.

Where μ _norm is the standard friction constant

μ _min is the minimum friction constant

        η is the brake efficiency

The system delay (t _sys-de ) calculated as above, the minimum response time (t _{h , min} ) of the user, the maximum deceleration (a _max ) of the vehicle, and the friction coefficient (f (μ) between the tire and the road surface) ), Calculate the minimum safety distance (d _safety ) and the minimum braking distance (d _braking ). Then, the collision alarm index W is calculated from the above values.

And collision time (TTC) and reverse collision time (TTC- ¹ )

The collision time (TTC) is the time until the collision when the preceding vehicle stops and the vehicle does not decelerate. The collision time (TTC) is emitted when the relative speed is 0, that is, when the two vehicles are stopped, so the reverse time is calculated by calculating the inverse collision time (TTC- ¹ ).

Then, the inter-vehicle distance control and collision reduction and collision prevention control method of the present invention by monitoring the calculation result of the step S150, the collision alarm index (W) is W ≥ 1, the reverse collision time (TTC ^-1 ) It is determined whether the first mode is TTC ^-1 <iT ₁ (S162). When the determination result corresponds to the first mode, the inter-vehicle distance control, collision reduction and collision avoidance control method of the present invention determines that the current driving situation is a general driving situation in which only the distance between the vehicle and the preceding vehicle is to be controlled and the target acceleration ( a _des (t)) to as shown in Figure _{4, a 1 <a des (} t) <a 2 and controls through (S172). In the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention, the collision warning index (W) is α <W <1 by monitoring the calculation result of step S150 and the reverse collision time (TTC- ^1). ) Is determined whether iT ₁ <TTC ^-1 <iT ₂ (S164). As a result of the determination, in the second mode, the inter-vehicle distance control, collision reduction and collision avoidance control method of the present invention is required to control the collision distance and collision prevention control as well as to control the distance between the vehicle with the preceding vehicle. The target acceleration a _des (t) is determined to be a driving condition to be controlled and is controlled between a ₃ <a _des (t) <a ₁ as shown in FIG. 4 (S174). In addition, in the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention by monitoring the calculation result of the step S150, the collision alarm index (W) is 0 <W <β, the reverse collision time (TTC ^-1 ) Determines whether iT ₂ < TTC ^-1 < iT ₃ in a third mode (S166). As a result of the determination, in the third mode, the inter-vehicle distance control, collision reduction, and collision avoidance control method of the present invention determines that the current driving situation is a driving situation in which collision reduction and collision prevention control is to be performed, and the target acceleration (a _des (t)) is controlled as a _des (t) = a ₃ as shown in FIG. 4 (S176). In the inter-vehicle distance control, collision reduction and collision prevention control method of the present invention, the collision warning index (W) is W ≤ γ by monitoring the calculation result of step S150, and the reverse collision time (TTC ^-1 ) is iT ₃ ≤ TTC ^{- 1} if, as the currently running condition of the vehicle is determined to be running conditions should the force collision mitigation and collision avoidance control are shown in Figure 4 to the target acceleration _{(a des (t)),} a des (t ) is controlled by a ₄ (S178).

Α, β, γ, iT ₁ , iT ₂ , and iT ₃ are parameters obtained by analyzing the driving characteristics of the driver.

Here, the inter-vehicle distance control, collision reduction and collision avoidance control method of the present invention is to control the target acceleration as described above and maintain the inter-vehicle distance with the preceding vehicle when the vehicle is currently driving in the first to fourth modes. The warning message and the collision warning message may be displayed or a warning sound and a collision warning sound may be generated to maintain the distance between the preceding vehicle.

As described above, the inter-vehicle distance control, collision reduction and collision avoidance control apparatus and method thereof according to an embodiment of the present invention controls the vehicle-to-vehicle distance control, collision reduction and collision prevention control using a single controller. Therefore, the inter-vehicle distance control, collision reduction and collision avoidance control apparatus and method of the present invention can reduce the production cost of an automobile.

In addition, the inter-vehicle distance control, collision reduction and collision avoidance control apparatus and method thereof according to an embodiment of the present invention controls the vehicle distance, collision reduction and impulse prevention in consideration of a driving road environment or weather conditions. Therefore, the inter-vehicle distance control, collision reduction and collision prevention control apparatus and method thereof of the present invention can ensure absolute safety of the driver.

Claims (5)

A millimeter wave radar sensor measuring presence or absence of a preceding vehicle, relative distance and relative speed with the preceding vehicle; A friction force estimator for estimating the friction force between the tire and the road surface; An acceleration sensor measuring acceleration of the vehicle; A driving characteristic analyzer configured to receive and store information from the millimeter wave radar sensor, the friction force estimator and the acceleration sensor, brake operation information, and the like to parameterize driving characteristics of a driver; A brake actuator for controlling the operation of the brake; Parameters for analyzing driving characteristics of the driver and driving information of the current vehicle are transmitted from the driving characteristic analyzer, and the collision warning index and the collision time are calculated and monitored based on the driving information of the current vehicle and the transmitted parameters, and the collision is calculated. Distance control and collision alleviation and collision prevention control device, characterized in that for controlling the brake actuator by calculating the target acceleration based on the alarm index and the back collision time. The method of claim 1, And the brake actuator reduces the vehicle speed or forcibly stops the vehicle according to the calculated target acceleration. The method of claim 1, An operation start signal generator for inputting an operation start signal for turning on the control unit by a driver's selection; Under the control of the controller, a collision warning signal including a display unit for displaying a warning message and a collision warning message for maintaining the distance between the preceding vehicle, and a speaker for generating a warning sound and a collision warning sound for maintaining the distance between the preceding vehicle. Inter-vehicle distance control, collision reduction and collision prevention control device further comprising a generator. A first step of measuring the presence or absence of the preceding vehicle, the relative distance and relative speed of the preceding vehicle, estimating the frictional force between the tire and the road surface, and measuring the acceleration of the vehicle; A second step of storing information measured and estimated in the first step and brake operation information while driving the vehicle; A third step of parameterizing driving characteristics of the driver by analyzing the information stored in the second step; A fourth step of determining whether an operation start signal according to the driver's selection is input; When the operation start signal is input in the fourth step, the collision alarm index W and the reverse collision time (TCC- ¹ ) using the information measured and estimated in the first step and the parameterized information in the third step Calculating a fifth step; Wherein said one said conflict alert index (W) and a reverse impact time calculated in the step 5 ^(-1 TCC) for monitoring and said conflict alert index (W) and a reverse impact time by controlling the target acceleration based on the ^(-1 TCC) Vehicle And a sixth step of slowing down the speed of the vehicle or stopping the vehicle. The method of claim 4, wherein And displaying a warning message and a collision warning message for maintaining the inter-vehicle distance with the preceding vehicle or generating a warning sound and a collision warning sound for maintaining the inter-vehicle distance with the preceding vehicle. And anti-collision control method.

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