CN106379316A - Vehicle active collision avoidance mode switching method - Google Patents

Abstract

The invention discloses a vehicle active collision avoidance mode switching method, and belongs to the technical field of driving safety. The vehicle active collision avoidance mode switching method comprises the following steps of: step 1: obtaining the driving information of a vehicle; step 2: analyzing the driving information of the vehicle, and establishing and calculating a longitudinal collision avoidance safety distance of the vehicle to obtain a collision avoidance warning distance Dw and a forced braking distance Db; step 3: determining whether to provide a collision avoidance warning or perform active collision avoidance by comparing a relative distance between the vehicle and a target vehicle to the collision avoidance warning distance and the forced braking distance; step 4: when the active collision avoidance is needed, performing an active collision avoidance mode switching judgment; and step 5: completing collision avoidance under the control of an electronic control unit so as to complete the action to be performed in the step 4, and feeding back the vehicle state information to a driving information acquisition control unit. Through the adoption of the vehicle active collision avoidance mode switching method disclosed by the invention, the vehicle can avoid a dangerous collision condition timely in the traveling process, and the safety factor of driving is improved significantly; and through the adoption of a horizontal safety distance model and the collision avoidance mode switching method provided by the invention, the active collision avoidance of the vehicle can be realized accurately.

Description

A kind of vehicle active collision avoidance mode switching method

Technical field

The present invention relates to a kind of vehicle active collision avoidance system mode switching method, belong to driving safety technical field.

Background technology

Improve constantly with the motor-driven trip requirements of the masses, automobile market potentiality sustained release, automobile pollution keeps quick Growth trend, by by the end of June, 2016, national vehicle guaranteeding organic quantity reaches 2.85 hundred million, wherein 1.84 hundred million, automobile；Motor vehicles are driven Sail people and reach 3.42 hundred million people, wherein motorist 2.96 hundred million people, propose thus to road traffic pressure and traffic safety Huge challenge, develops the urgent needss that advanced active safety systems of vehicles is Modern road traffic.Vehicle active safety system Important step in system is the research and development of the Active collision avoidance system of vehicle.Vehicle active collision avoidance system mainly includes longitudinal master Dynamic anti-collision system and horizontal Active collision avoidance system.Longitudinal active collision avoidance controls mainly by cutting to air throttle and brake actuator Change and coordinate to realize accurately following to expectation acceleration.But the polytropy due to external environment and the complexity of vehicle structure Property, cause longitudinal Active collision avoidance system brake safe distance more than actual two spacings thus producing the not enough danger of braking distance Danger, is now accomplished by executing collision avoidance action to turn to the horizontal Active collision avoidance system as control object for the executor.

Content of the invention

Present disclosure is to solve the above problems, in active collision avoidance longitudinal direction safe distance and transverse safety distance mould Propose a kind of vehicle active collision avoidance system mode switching method on the basis of type, automobile can be made timely to evade when driving Hazardous collision operating mode, the hour of danger that vehicle active collision avoidance system pattern switching can be hit before vehicle occurs sends alarm signal Breath, and realize brake hard longitudinal direction collision avoidance under emergency situation or realize turning to the horizontal collision avoidance of lane-change such that it is able to effectively Improve the driving safety of automobile.Concrete technical scheme is as follows:

A kind of vehicle active collision avoidance mode switching method, comprises the steps：

Step 1：Obtain vehicle driving information；

Step 2：By analyzing vehicle driving information, set up longitudinal direction of car collision avoidance safe distance and calculate, obtain collision avoidance pre- Police is apart from D_wAnd forced brake is apart from D_b；

Step 3：By from car and target carriage relative distance and the comparison of intelligent collision warning distance and forced brake distance To whether carrying out intelligent collision warning or active collision avoidance；

Step 4:When needing to carry out active collision avoidance, carry out active collision avoidance pattern switching and judge；

Step 5:Action to be performed for step 4 is controlled by an electronic control unit and completes collision avoidance, then repeatedly execute step Rapid 1- step 5.

Further, described step 1 implement including：Obtain vehicle front and both sides information using trailer-mounted radar；Profit Obtain travel speed V of target carriage with vehicle-mounted sensor-based system_f, relative distance D between car and front truck_relative, from the traveling of car Speed V_r, from car acceleration a_r-max, and collection track vehicle position information.

Further, in described step 2, the computational methods of intelligent collision warning distance and forced brake distance include：

$D_w=\frac{{v_x}^2}{2a_{r-max}}+(v_x-V_f)(T_{r-d}+T_{r-b})-\frac{{V_f}^2}{2a_f}+d_0$

$D_b=\frac{{v_x}^2}{2a_{r-max}}+(v_x-V_f)T_{br}-\frac{{V_f}^2}{2a_f}+d_0$

In formula：D_w:Intelligent collision warning distance；D_b:Forced brake distance；d₀:After representing that relative velocity eliminates, from car and target Workshop is still to the distance keeping；T_r-d:Time of driver's reaction, driver finds front vehicles and takes braking maneuver, steps on to foot The time of upper brake pedal；T_r-b:Car brake system response and braking time；T_brRepresent the brake system response time；v_x:From car Speed, V_f:Target carriage speed, a_r-max:From car acceleration, a_f:Target carriage acceleration.

Further, described step 3 implement including：

Relative distance D of measurement_relative≥D_w, system no control action；Relative distance D of measurement_w≥D_relative≥D_b When, intelligent collision warning is carried out to driver, driver's brakeless action after early warning；Relative distance D of measurement_relative≤D_bWhen, then System carries out active collision avoidance.

Further, the implementing including following situation of described step 4：

1. operating mode 1：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is in the position after a while from car； Take longitudinal active collision avoidance pattern under this operating mode, control motor vehicle braking system to carry out brake hard；

2. operating mode 2：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is in from car and from car track The centre position of target carriage, takes longitudinal active collision avoidance pattern under this operating mode, control motor vehicle braking system to carry out brake hard；

3. operating mode 3：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is being leaned on from the target carriage in track Front position, carries out the judgement of longitudinal active collision avoidance and horizontal active collision avoidance pattern switching, specifically under this operating mode：

Set up transverse safety distance model：

$D_{AB}=\sqrt{{(\frac{D_{relative}}{v_x}-t)}^2+{\[\frac{d}{2}-\frac{y_e{v}_x}{D_{relative}-d_0}t+\frac{y_e}{2\mathrm{\π}}\sin \left(\frac{2{\mathrm{\πv}}_x}{D_{relative}-d_0}t\right)+\frac{d}{2}\]}^2}$

In formula：

D_AB:Transverse safety distance, is from car and the distance from track target carriage；

y_e:Lane width, from vehicle-width, t represents the lane-change persistent period to d；

Arranging collision avoidance pattern switching Rule of judgment is：WhenWhen, vehicle is indulged To active collision avoidance, whenVehicle carries out horizontal active collision avoidance, controls wheel steering system execution collision avoidance action；

4. operating mode 4：There is target carriage from car track, adjacent track does not have target carriage, using the method for operating mode 3, enter row mode and cut Change, then carry out the active collision avoidance of vehicle.

Further, d₀Selection numerical value is 2-5 rice；T_r-d:Selection numerical value is the 0.3-1 second；T_r-bChoosing numerical value is 0.3 second；T_br Choosing numerical value is 0.3 second.

Beneficial effects of the present invention include：

(1) present invention proposes a kind of mode switching method of vehicle active collision avoidance, is capable of vehicle and is running over journey In timely evade hazardous collision operating mode, significantly improve the safety coefficient of driving；

(2) present invention establishes vehicle active collision avoidance longitudinal direction and transverse safety distance model, can accurately and effectively sentence The driving operating mode of disconnected vehicle ensures traffic safety it is achieved that evading road traffic dangerous working condition in advance.

Brief description

Fig. 1 is method of the present invention flow chart；

Fig. 2 is present invention driving operating mode 1；

Fig. 3 is present invention driving operating mode 2；

Fig. 4 is present invention driving operating mode 3；

Fig. 5 is present invention driving operating mode 4；

Specific embodiment

The present invention is described in further detail with reference to the accompanying drawings and examples.

The present invention provides a kind of vehicle active collision avoidance system mode switching method, as shown in figure 1, including following step Suddenly：

Step 1：Obtain vehicle driving information.

Vehicle mounted imaging apparatus may be mounted in vehicle front bumper, for the situation of vehicle front is transmitted electron control Unit ECU processed；Trailer-mounted radar is set to five, and wherein 3 split in the both sides of vehicle front bumper bar and centre position, in addition Two centre positions being individually positioned between the Qianmen of both sides and back door, for by vehicle both sides and road ahead information status (distance of vehicle and barrier) is transferred to electronic control unit ECU, and vehicle-mounted sensor-based system obtains travel speed V of target carriage_f、 And relative distance D in a workshop in front and back_relative, from travel speed V of car_r, from car acceleration a_r-max, and collection track car Positional information.

Step 2：By analyzing vehicle driving information, set up longitudinal direction of car collision avoidance safe distance and calculate, obtain collision avoidance pre- Alert distance and forced brake distance.

$D_w=\frac{{v_x}^2}{2a_{r-max}}+(v_x-V_f)(T_{r-d}+T_{r-b})-\frac{{V_f}^2}{2a_f}+d_0---\left(1\right)$

$D_b=\frac{{v_x}^2}{2a_{r-max}}+(v_x-V_f)T_{br}-\frac{{V_f}^2}{2a_f}+d_0---\left(2\right)$

In formula：

D_w:Intelligent collision warning distance, if that is, two spacings with D_w、D_bBetween should report to the police.

D_b:Forced brake distance, if that is, two spacings are less than D_bShould brake, for urgent collision avoidance boundary value.

d₀:After representing that relative velocity eliminates, it is still to the distance keeping from car and target workshop, general numerical value of choosing is 2-5 Rice.

T_r-d:Time of driver's reaction, driver finds front vehicles and takes braking maneuver, steps on brake pedal to foot Time, general numerical value of choosing is the 0.3-1 second.

T_r-b:Car brake system response and braking time, general numerical value of choosing is 0.3 second.

T_brRepresent the brake system response time, general selection 0.3 second.

v_x:From car speed, V_f:Target carriage speed, a_r-max:From car acceleration, a_f:Target carriage acceleration.

Step 3：By from car and target carriage relative distance and the comparison of intelligent collision warning distance and forced brake distance To whether carrying out intelligent collision warning.

Relative distance D of measurement_relative≥D_w, system no control action；Relative distance D of measurement_w≥D_relative≥D_b When, intelligent collision warning is carried out to driver, driver's brakeless action after early warning；Relative distance D of measurement_relative≤D_bWhen, then System carries out active collision avoidance.

Step 4:When needing to carry out active collision avoidance, carry out active collision avoidance pattern switching and judge.Including several situations as follows：

1. operating mode 1 as shown in Figure 2, has target carriage from car track with adjacent track, and target carriage 2 is in the position after a while from car Put, now such as carry out horizontal active collision avoidance it may happen that collision danger, so taking longitudinal active collision avoidance pattern under operating mode, Motor vehicle braking system is controlled to carry out brake hard.

2. operating mode 2 as shown in Figure 3, has target carriage from car track with adjacent track, and target carriage 2 is in from car and target carriage 1 centre position, collision avoidance pattern is similar with operating mode 1, now such as carry out horizontal active collision avoidance it may happen that collision danger, therefore Take longitudinal active collision avoidance pattern under this operating mode, control motor vehicle braking system to carry out brake hard.

3. operating mode 3 as shown in Figure 4, has target carriage from car track with adjacent track, and target carriage 2 is in the forward position of target carriage 1 Put, now carry out the judgement of longitudinal active collision avoidance and horizontal active collision avoidance pattern switching, formula (3) is set up according to Fig. 5 and laterally pacifies Full distance model：

$D_{AB}=\sqrt{{(\frac{D_{relative}}{v_x}-t)}^2+{\[\frac{d}{2}-\frac{y_e{v}_x}{D_{relative}-d_0}t+\frac{y_e}{2\mathrm{\π}}\sin \left(\frac{2{\mathrm{\πv}}_x}{D_{relative}-d_0}t\right)+\frac{d}{2}\]}^2}---\left(3\right)$

In formula：

D_AB:Transverse safety distance, is the B point distance from car A point and target carriage 1.

y_e:Lane width, d is from vehicle-width.T represents the lane-change persistent period.

By the collision avoidance pattern switching Rule of judgment of formula (2) and formula (3) it is：

WhenWhen, vehicle carries out longitudinal active collision avoidance, whenVehicle carries out horizontal active Collision avoidance, controls wheel steering system execution collision avoidance action.

4. as shown in Figure 5 operating mode 4, has target carriage from car track, adjacent track does not have target carriage then, collision avoidance operating mode and operating mode 3 Similar.According to the Rule of judgment of active collision avoidance pattern switching, carry out pattern switching, then the active collision avoidance carrying out vehicle.

Step 5:Action to be performed for step 4 is controlled by an electronic control unit and completes collision avoidance, then repeatedly execute step Rapid 1- step 5.

Taking operating mode in Fig. 43 as a example:

1. obtain vehicle driving information first.

2. pass through analyze vehicle driving information, set up longitudinal direction of car collision avoidance safe distance and calculate, obtain intelligent collision warning away from From and forced brake with a distance from.

3. by from car and target carriage relative distance and intelligent collision warning distance and forced brake distance being relatively No carry out intelligent collision warning.Relative distance D of measurement_w≥D_relative≥D_bWhen, intelligent collision warning is carried out to driver；Drive after early warning Member's brakeless action, relative distance D of measurement_relative≤D_bWhen, then system carries out active collision avoidance.

4. carry out active collision avoidance pattern switching according to step 3 gained order to judge, nowVehicle is carried out Laterally active collision avoidance, controls wheel steering system execution collision avoidance action.

5. electronic control unit ECU is fed back to according to the action that step 4 is carried out, controlled by ECU and complete collision avoidance.

This control method can make automobile timely evade hazardous collision operating mode, vehicle active collision avoidance system when driving The hour of danger alert that system can hit before vehicle occurs, and realize brake hard longitudinal direction collision avoidance under emergency situation Or realize turning to the horizontal collision avoidance of lane-change such that it is able to effectively improve the driving safety of automobile.

Above are only technical solution of the present invention and the explanation of specific embodiment, the protection model being not intended to limit the present invention Enclose, without prejudice on the premise of flesh and blood of the present invention and principle, changed, retouch etc. all within protection domain.

Claims (6)

1. a kind of vehicle active collision avoidance mode switching method is it is characterised in that comprise the steps：

Step 1：Obtain vehicle driving information；

Step 2：By analyze vehicle driving information, set up longitudinal direction of car collision avoidance safe distance and calculate, obtain intelligent collision warning away from From D_wAnd forced brake is apart from D_b；

Step 3：By from car and target carriage relative distance and intelligent collision warning distance and forced brake distance being relatively No carry out intelligent collision warning or active collision avoidance；

Step 4:When needing to carry out active collision avoidance, carry out active collision avoidance pattern switching and judge；

Step 5:Action to be performed for step 4 is controlled by an electronic control unit and completes collision avoidance, then execution step 1- repeatedly Step 5.

2. a kind of vehicle active collision avoidance mode switching method according to claim 1 is it is characterised in that described step 1 Implement including：Obtain vehicle front and both sides information using trailer-mounted radar；Obtain target carriage using vehicle-mounted sensor-based system Travel speed V_f, relative distance D between car and front truck_relative, from travel speed V of car_r, from car acceleration a_r-max, and Collection track vehicle position information.

3. a kind of vehicle active collision avoidance mode switching method according to claim 2 is it is characterised in that in described step 2 The computational methods of intelligent collision warning distance and forced brake distance include：

$D_w=\frac{{v_x}^2}{{a_2}_{r-max}}+(v_x-V_f)(T_{r-d}+T_{r-b})-\frac{{V_f}^2}{2a_f}+d_0$

$D_b=\frac{{v_x}^2}{{a_2}_{r-max}}+(v_x-V_f)T_{br}-\frac{{V_f}^2}{{a_2}_f}+d_0$

In formula：D_w:Intelligent collision warning distance；D_b:Forced brake distance；d₀:After representing that relative velocity eliminates, from car and target workshop It is still to the distance keeping；T_r-d:Time of driver's reaction, driver finds front vehicles and takes braking maneuver, steps on system to foot The time of dynamic pedal；T_r-b:Car brake system response and braking time；T_brRepresent the brake system response time；v_x:From car speed, V_f:Target carriage speed, a_r-max:From car acceleration, a_f:Target carriage acceleration.

4. a kind of vehicle active collision avoidance mode switching method according to claim 3 is it is characterised in that described step 3 Implement including：

Relative distance D of measurement_relative≥D_w, system no control action；Relative distance D of measurement_w≥D_relative≥D_bWhen, right Driver carries out intelligent collision warning, driver's brakeless action after early warning；Relative distance D of measurement_relative≤D_bWhen, then system is entered Row active collision avoidance.

5. a kind of vehicle active collision avoidance mode switching method according to claim 3 is it is characterised in that described step 4 Implement including following situation：

1. operating mode 1：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is in the position after a while from car；This work Take longitudinal active collision avoidance pattern under condition, control motor vehicle braking system to carry out brake hard；

2. operating mode 2：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is in from car and from car track target The centre position of car, takes longitudinal active collision avoidance pattern under this operating mode, control motor vehicle braking system to carry out brake hard；

3. operating mode 3：There is target carriage from car track and adjacent track, and the target carriage in adjacent track is forward in the target carriage from track Position, carries out the judgement of longitudinal active collision avoidance and horizontal active collision avoidance pattern switching, specifically under this operating mode：

Set up transverse safety distance model：

$D_{AB}=\sqrt{{\left(\frac{D_{relative}}{v_x}-t\right)}^2+{\[\frac{d}{2}-\frac{y_e{v}_x}{D_{relative}-d_0}t+\frac{y_e}{2\mathrm{\π}}si\left(\frac{2{\mathrm{\πv}}_x}{D_{relative}-d_0}t\right)+\frac{d}{2}\]}^2}$

In formula：

D_AB:Transverse safety distance, is from car and the distance from track target carriage；

y_e:Lane width, from vehicle-width, t represents the lane-change persistent period to d；

Arranging collision avoidance pattern switching Rule of judgment is：WhenWhen, vehicle carries out longitudinal master Dynamic collision avoidance, whenVehicle carries out horizontal active collision avoidance, controls wheel steering system execution collision avoidance action；

4. operating mode 4：There is target carriage from car track, adjacent track does not have target carriage, using the method for operating mode 3, carry out pattern switching, then Carry out the active collision avoidance of vehicle.

6. a kind of vehicle active collision avoidance mode switching method according to claim 3 is it is characterised in that d₀Choosing numerical value is 2-5 rice；T_r-d:Selection numerical value is the 0.3-1 second；T_r-bChoosing numerical value is 0.3 second；T_brChoosing numerical value is 0.3 second.