CN105857075B - Fatigue drive of car security protection system and method - Google Patents

Abstract

The invention relates to the technical field of automobile electronics, in particular to a safety protection system and method for automobile fatigue driving, including a fatigue driving warning system, a system switch input unit, an accelerator opening signal unit, an engine speed signal unit, a vehicle speed signal unit, a system controller, an engine Controller, oil pump relay unit and electronic stability control system; the system controller judges the fatigue level according to various input signals, and outputs corresponding instructions to the engine controller, oil pump relay unit and electronic stability control system according to the fatigue level. According to the recognized fatigue intensity of the driver, limit the opening of the engine accelerator, whether to cut off the fuel, and whether to brake, so that the driver can drive at a safe speed without stopping the fuel and limiting the opening of the accelerator when he is slightly fatigued, effectively avoiding accidents. Stepping on the accelerator will cause traffic accidents; at the same time, when the fatigue intensity is too high, cut off the oil and brake in an emergency to ensure personal safety.

Description

Automobile fatigue driving safety protection system and method

technical field

The invention relates to the technical field of automobile electronics, in particular to an automobile fatigue driving safety protection system and method.

Background technique

Motor vehicles drive for a long time, the driver is prone to fatigue, especially now that the work pressure is high, the driver is unresponsive when driving tired, and it is difficult to deal with it in time when an emergency occurs. In addition, due to the large inertia of some large trucks, the braking distance is too long, which is more prone to traffic accidents. According to the survey, my country's road traffic accidents have been on the rise, and traffic accidents caused by fatigue driving account for a large proportion of traffic accidents. Therefore, it is necessary to invent a method to avoid safety accidents caused by fatigue driving.

Contents of the invention

In order to solve the above-mentioned technical problems, the present invention provides an automobile fatigue driving safety protection system and method that help reduce fatigue driving traffic accidents.

For an automobile fatigue driving safety protection system according to the present invention, its technical solution is as follows: a fatigue driving warning system, a system switch input unit, an accelerator opening signal unit, an engine speed signal unit, a vehicle speed signal unit, a system controller, and an engine control unit. switch, oil pump relay unit and electronic stability control system;

The fatigue driving warning system outputs the driver fatigue intensity S, the system switch input unit outputs the enable signal, the throttle opening signal unit outputs the throttle opening P, the engine speed signal unit outputs the engine speed n, and the vehicle speed signal unit outputs the vehicle speed v to the system A controller, the system controller judges the fatigue level according to various input signals, and outputs corresponding instructions to the engine controller, the oil pump relay unit and the electronic stability control system according to the fatigue level.

Further, it also includes an audio-visual entertainment system host and a vehicle body controller, the audio-visual entertainment system host is used to receive the in-vehicle voice prompt signal sent by the system controller, and the vehicle body controller is used to receive the vehicle body double-flash alarm sent by the system controller Signal.

Further, the system controller communicates with the fatigue driving warning system, system switch input unit, accelerator opening signal unit, engine speed signal unit, vehicle speed signal unit, audio-visual entertainment system host, vehicle body controller and electronic stability control system through CAN communication.

For a safety protection method for automobile fatigue driving according to the present invention, the technical solution is to receive the driver's fatigue intensity signal, judge the fatigue level according to the driver's fatigue intensity, and output corresponding actions according to the fatigue level:

When it is judged to be driving without fatigue, the driver's requested throttle opening P is used as the output throttle opening;

When it is judged as mildly fatigued driving, if the driver's requested throttle opening P does not exceed the throttle opening limit value P _lim , then the driver's requested throttle opening P will be used as the output throttle opening; if the driver's requested throttle opening P If the throttle opening limit P _lim is exceeded, the throttle opening limit P _lim is used as the output throttle opening;

When it is judged as moderate fatigue driving, the output throttle opening is 0;

When it is judged as severe fatigue driving, the output throttle opening is 0, and the fuel cut-off and emergency braking are performed.

Further, the fatigue grade is judged according to the specific fatigue strength _SN :

When 0≤S _N ≤a, it is fatigue-free driving;

When a<S _N ≤b, driving with mild fatigue;

When b<S _N ≤c, driving with moderate fatigue;

When c<S _N ≤1, driving with severe fatigue;

The specific fatigue intensity S _N is the value obtained by normalizing the driver fatigue intensity S, and the values a, b, and c are the thresholds for mildly fatigued driving, moderately fatigued driving, and severely fatigued driving, respectively.

Further, when driving with mild fatigue, the calculation process of the throttle opening limit value P _lim is as follows:

Using the method of calibration look-up table, according to the value of the specific fatigue strength S _N , the corresponding initial throttle opening limit value P(S _N ) _lim is obtained;

Calculate the speed compensation factor f ₁ (n) of the engine speed n, the Described P _lim (n) is the safety throttle opening limit value under different engine speeds, obtains by test calibration;

Calculate the vehicle speed compensation factor f ₂ (v) of the vehicle speed v, the Described P _lim (v) is the safety throttle opening limit value under different vehicle speeds, obtains by test calibration;

The throttle opening limit value P _lim =P(S _N ) _lim ×f ₁ (n) ×f ₂ (v).

Further, when x ₁ <S _N <x ₂ , the initial throttle opening limit P(S _N ) _lim is calculated by linear interpolation, namely The f(x ₁ ) and f(x ₂ ) are the corresponding initial accelerator opening limits when the specific fatigue strength S _N takes x ₁ and x ₂ respectively.

Further, during the mildly fatigued driving, an in-vehicle voice prompt signal is sent to remind the driver that the driver is in a mildly fatigued driving state.

Further, when driving with moderate fatigue, an in-vehicle voice prompt signal is sent to remind the driver that the driver is in a dangerous driving state.

Further, when driving with severe fatigue, an in-vehicle voice prompt signal is sent to remind the driver that the driver is in a dangerous driving state, a double flashing alarm signal is sent on the vehicle body, and at the same time, the vehicle is controlled to cut off fuel and perform emergency braking.

Beneficial effects of the present invention: limit the opening of the engine throttle, whether to cut off the fuel, and whether to brake according to the identified fatigue intensity of the driver, so that the driver can drive at a safe speed without stopping the fuel and limiting the throttle opening when he is slightly fatigued. Driving can effectively avoid traffic accidents caused by mistakenly stepping on the accelerator; at the same time, when the fatigue intensity is too high, cut off the fuel and brake in an emergency to ensure personal safety. However, due to the limitation of the throttle opening after mild fatigue and moderate fatigue, the engine system will cut off fuel, the combustion torque will decrease, the engine speed will return to idle speed, and the vehicle speed will also be reduced to the minimum speed for stable driving of the vehicle. Emergency braking under fatigue will not cause the vehicle to overturn and endanger personal safety.

Description of drawings

Fig. 1 is the connection schematic diagram of a kind of automobile fatigue driving safety protection system of the present invention;

Fig. 2 is the control flowchart of a kind of automobile fatigue driving safety protection method of the present invention;

Fig. 3 is the calculation process of throttle opening limit value P _lim when mild fatigue driving of the present invention;

In the picture:

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

As shown in Figure 1, a safety protection system for automobile fatigue driving includes a fatigue driving warning system 1, a system switch input unit 2, an accelerator opening signal unit 3, an engine speed signal unit 4, a vehicle speed signal unit 5, a system control (ECU ) 6, engine controller (EMS) 7, audio-visual entertainment system host 8, body controller (BCM) 9, oil pump relay unit 10, brake signal, and electronic stability control system (ESC) 11. Fatigue driving warning system 1, system switch input unit 2, accelerator opening signal unit 3, engine speed signal unit 4 and vehicle speed signal unit 5 communicate with the system controller 6 through the CAN line, and the system control 6 communicates with the engine controller 7 through the CAN line Communication, the system controller 6 outputs the oil cut-off signal and sends it to the oil pump relay unit 10 through the hard line, the system controller 6 outputs the voice prompt signal in the car and communicates with the audio-visual entertainment system host 8 through the CAN line, the system controller 6 outputs the vehicle body dual The alarm signal flashes and communicates with the vehicle body controller 9 through the CAN line, and the system controller 6 outputs the brake signal and communicates with the electronic stability control system 11 through the CAN line.

As shown in Figure 2, it is a control flowchart of a safety protection method for automobile fatigue driving, which is specifically described in conjunction with the following embodiments:

The system switch input unit 2 controls the startup and shutdown of the system, and the fatigue driving warning system 1 outputs the driver fatigue intensity S, which is output to the system control 6 through the CAN line, wherein the driver fatigue intensity S is calculated in the prior art.

After the system switch input unit 2 controls the system to start, the fatigue driving warning system 1 outputs the driver fatigue intensity S, the engine speed signal unit 3 outputs the engine speed n, and the vehicle speed signal unit 4 outputs the vehicle speed v to the system control 6 . The system control 6 normalizes the received driver fatigue intensity S to obtain S _N , that is, _0≤SN≤1 . And the normalized fatigue driving intensity _SN is determined according to the driving intensity limit into four levels: no fatigue driving, mild fatigue driving, moderate fatigue driving and severe fatigue driving. Judgment basis: when 0≤S _N ≤0.05, driving without fatigue; when 0.05< _SN ≤0.5, driving with mild fatigue; when 0.5< _SN ≤0.8, driving with moderate fatigue; when 0.8< _SN ≤1, driving with severe fatigue. Among them, 0.05, 0.5, and 0.8 are the thresholds of mild fatigue driving, moderate fatigue driving, and severe fatigue driving respectively, which can be calibrated according to the actual situation.

(1) When it is determined that there is no fatigue driving, the system does not perform any operation and maintains the driver's intention, that is, the throttle opening limit P _lim is equal to the driver's requested throttle opening P, and P _lim =P.

(2) When it is judged as mildly fatigued driving, throttle opening P _lim is restricted to different degrees according to specific fatigue intensity _SN , engine speed n and vehicle speed v.

In the embodiment provided by the present invention, firstly, the initial throttle opening limit value P(S _N ) _lim is calculated according to the fatigue strength _SN . When S _N ＝[0.05, 0.1, 0.15, 0.2, 0, 25, 0.3, 0.35, 0.4, 0.45, 0.5], the initial throttle opening limit P(S _N ) _lim = [60%, 56%, 52 %, 46%, 40%, 30%, 18%, 8%, 6%, 5%], this value is obtained by calibration look-up table, that is, when S _N =0.1, P(S _N ) _lim =56%; When S _N =0.15, P(S _N ) _lim =52%, and so on. When x ₁ <S _N <x ₂ , the initial throttle opening limit P(S _N ) _lim is calculated by linear interpolation, namely f(x ₁ ) and f(x ₂ ) are the initial accelerator opening limits corresponding to the specific fatigue strength S _N taking x ₁ and x ₂ respectively. Such as 0.1< _SN <0.15, there is That is, P(S _N ) _lim =52%+(0.15-S _N )×80%. By analogy, the initial throttle opening limit P(S _N ) _lim of other intervals is obtained. The system controller 6 compensates the initial accelerator opening limit value according to the engine speed n and the vehicle speed v to obtain the final accelerator opening limit value P _lim , the calculation formula of which is: P _lim =P(S _N ) _lim ×f ₁ ( n)×f ₂ (v).

Among them, f ₁ (n) is the speed compensation factor of engine speed n; f ₂ (v) is the vehicle speed compensation factor of vehicle speed v. Through the test collection, the vehicle speed is constant and the engine speed changes, and multiple sets of tests are carried out at different engine speeds, and the safety throttle opening limit P _lim (n) at different speeds is tested and calibrated, and finally the speed compensation factor is obtained. That is, when the engine speed n=n ₀ , the speed compensation factor f ₁ (n ₀ ) has:

The speed compensation factor f ₁ (n) at all engine speeds is obtained by this method.

In the same way, the test collection is performed while the engine speed is constant and the vehicle speed is changed. Multiple sets of tests are carried out at different vehicle speeds. The tests calibrate the safety throttle opening limit P _lim (v) at different vehicle speeds, and finally obtain the rotational speed compensation factor. That is, when the vehicle speed v=v ₀ , the rotational speed compensation factor f ₂ (v ₀ ) has:

The rotational speed compensation factor f ₂ (v) at all vehicle speeds is obtained by this method.

As shown in Figure 3, it is a block diagram of the system control when driving with mild fatigue.

The system controller ECU6 sends the received accelerator command of the throttle opening value P to the engine controller 7 through the CAN line: if the driver requests the throttle opening value P to be smaller than P _lim , then the driver requests the throttle opening value P through the CAN line. line to the engine controller 7; if the driver requests the throttle opening value P to be greater than or equal to P _lim , the throttle command of the throttle opening limit value P _lim will be sent to the engine through the CAN line instead of the driver’s request for the throttle opening value P controller7. Simultaneously, the system controller ECU6 sends a voice prompt signal in the car, and sends it to the audio-visual entertainment system host 8 through the CAN line, and reminds the driver to be in a mildly fatigued driving state by voice.

(3) When it is judged as moderately fatigued driving, the limit throttle opening is 0, that is, P _lim =0, and the accelerator pedal does not work at this time, that is, the system controller 6 replaces the driver's request with an accelerator opening value of 0. The throttle opening value P is sent to the engine controller 9 through the CAN line. Simultaneously, the system controller 6 sends the voice prompt signal in the car, and sends it to the audio-visual entertainment system host 8 through the CAN line, and reminds the driver to be in a dangerous driving state by voice.

(4) When it is judged as severe fatigue driving, the system controller 6 sends the throttle opening value 0 to the engine controller 7 through the CAN line, that is, P _lim =0, and sends an oil cut command to the oil pump relay unit 10, and the system cuts off At the same time, the brake command is sent to the electronic stability control system 11 through the CAN line, and the vehicle brakes in an emergency; at the same time, the system controller 6 sends the voice prompt signal in the car, and sends it to the audio-visual entertainment system host 8 through the CAN line, and reminds the vehicle by voice The driver has been driving dangerously. In addition, the system controller 6 sends a car body double flash alarm signal, and sends it to the car body controller 11 through the CAN line, so as to realize the car light double flash alarm.

Because the throttle opening is limited after mild fatigue and moderate fatigue, the engine system will cut off fuel, the combustion torque will decrease, the engine speed will return to the idle state, and the vehicle speed will also be reduced to the minimum speed for stable driving of the vehicle, at 10km/h h, emergency braking under severe fatigue will not cause the vehicle to roll over and endanger personal safety.

The above is only a specific embodiment of the present invention. It should be pointed out that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention shall be covered by the protection scope of the present invention. within.

Claims (9)

1. The utility model provides a car driver fatigue safety protection system which characterized in that: the system comprises a fatigue driving early warning system (1), a system switch input unit (2), an accelerator opening degree signal unit (3), an engine rotating speed signal unit (4), a vehicle speed signal unit (5), a system controller (6), an engine controller (7), an oil pump relay unit (10) and an electronic stability control system (11);

the fatigue driving early warning system (1) outputs fatigue strength S of a driver, the system switch input unit (2) outputs an enable signal, the accelerator opening degree signal unit (3) outputs accelerator opening degree P, the engine rotating speed signal unit (4) outputs engine rotating speed n, the vehicle speed signal unit (5) outputs vehicle speed v to the system controller (6), the system controller (6) judges fatigue grades according to various input signals, and outputs corresponding instructions to the engine controller (7), the oil pump relay unit (10) and the electronic stability control system (11) according to the fatigue grades;

the fatigue grades comprise no fatigue driving, light fatigue driving, moderate fatigue driving and severe fatigue driving;

when the fatigue grade is light fatigue driving, if the driver requests that the accelerator opening P does not exceed the accelerator opening limit value P_limIf so, the system controller (6) takes the accelerator opening P requested by the driver as the output accelerator opening; if the driver requests that the accelerator opening P exceeds the accelerator opening limit value P_limThe system controller (6) will set the throttle opening limit value P_limAs an output throttle opening;

wherein, the throttle opening limit value P_limThe calculation process of (2) is as follows:

by using a calibration table look-up method according to the specific fatigue strength S_NIs obtained corresponding to the initial throttle opening degree limit value P (S)_N)_lim；

Calculating a speed compensation factor f for an engine speed n₁(n) the aboveThe P is_lim(n) is the opening limit value of the safe accelerator at different engine rotating speeds, and is obtained through test calibration;

vehicle speed compensation factor f for calculating vehicle speed v₂(v) SaidThe P is_lim(v) Obtaining the opening limit values of the safe accelerator at different vehicle speeds through test calibration;

the throttle opening limit value P_lim＝P(S_N)_lim×f₁(n)×f₂(v)。

2. The automobile fatigue driving safety protection system according to claim 1, wherein: still include audio-visual entertainment system host computer (8) and automobile body controller (9), audio-visual entertainment system (8) host computer is used for receiving the interior voice prompt signal of car that system controller (6) sent, automobile body controller (9) are used for receiving the automobile body that system controller (6) sent and dodge alarm signal two times.

3. The automobile fatigue driving safety protection system according to claim 2, wherein: the system controller (6) is communicated with the fatigue driving early warning system (1), the system switch input unit (2), the accelerator opening degree signal unit (3), the engine rotating speed signal unit (4), the vehicle speed signal unit (5), the audio-visual entertainment system host (8), the vehicle body controller (9) and the electronic stability control system (11) through the CAN.

4. The safety protection method for the fatigue driving of the automobile is characterized by receiving a fatigue strength signal of a driver, judging a fatigue grade according to the fatigue strength of the driver, and outputting corresponding actions according to the fatigue grade:

when fatigue driving is judged to be absent, taking the accelerator opening P requested by the driver as an output accelerator opening;

when the driver judges that the driver is in light fatigue driving, if the driver requests that the accelerator opening P does not exceed the accelerator opening limit value P_limTaking the accelerator opening P requested by the driver as the output accelerator opening; if the driver requests that the accelerator opening P exceeds the accelerator opening limit value P_limThen the throttle opening degree limit value P is set_limAs an output throttle opening;

when the fatigue driving is judged to be moderate, the opening degree of an output accelerator is 0;

when the driver is judged to be in severe fatigue driving, the opening of the output accelerator is 0, and oil is cut off and emergency braking is carried out;

the throttle opening limit value P_limThe calculation process of (2) is as follows:

by using a calibration table look-up method according to the specific fatigue strength S_NIs obtained corresponding to the initial throttle opening degree limit value P (S)_N)_lim；

Calculating a speed compensation factor f for an engine speed n₁(n) the aboveThe P is_lim(n) is the opening limit value of the safe accelerator at different engine rotating speeds, and is obtained through test calibration;

vehicle speed compensation factor f for calculating vehicle speed v₂(v) SaidThe P is_lim(v) Obtaining the opening limit values of the safe accelerator at different vehicle speeds through test calibration;

the throttle opening limit value P_lim＝P(S_N)_lim×f₁(n)×f₂(v)。

5. The method for safety protection against fatigue driving of automobile according to claim 4, wherein the fatigue grade is determined according to specific fatigue strength S_NAnd (4) judging:

when 0 is less than or equal to S_NA is less than or equal to a, and the driver is fatigue-free driving;

when a < S_NB is less than or equal to b, and is mild fatigue driving;

when b < S_NC is less than or equal to c, which is moderate fatigue driving;

when c < S_NLess than or equal to 1, which is severe fatigue driving;

the specific fatigue strength S_NAnd the values obtained by the driver fatigue strength S normalization processing are respectively light fatigue driving, moderate fatigue driving and severe fatigue driving threshold values.

6. The method of claim 5, wherein x is the number of x₁＜S_N＜x₂When the initial throttle opening degree limit value P (S)_N)_limCalculated by linear interpolation, i.e.The f (x)₁) And f (x)₂) To a specific fatigue strength S_NRespectively take x₁And x₂The corresponding initial throttle opening limit value.

7. The automobile fatigue driving safety protection method according to claim 4, characterized in that: and sending an in-vehicle voice prompt signal to prompt the driver to be in a light fatigue driving state during the light fatigue driving.

8. The method for protecting safety against fatigue driving of an automobile according to claim 4, wherein during the moderate fatigue driving, an in-automobile voice prompt signal is sent to prompt the driver to be in a dangerous driving state.

9. The automobile fatigue driving safety protection method according to claim 4, wherein during severe fatigue driving, an in-automobile voice prompt signal is sent to prompt a driver to be in a dangerous driving state, a vehicle body double-flash alarm signal is sent, and meanwhile, the fuel cut of the automobile is controlled, and emergency braking is carried out.