CN201998980U - Detection and control system applied into electronic mechanical brake system of motor vehicle - Google Patents

Abstract

The utility model discloses a detection and control system applied into an electronic mechanical brake system of a motor vehicle, which comprises an electronic control unit. An acceleration sensor and a yawing angular speed sensor are arranged in the electronic control unit and respectively connected with the electronic control unit by signal circuits. The detection and control system can effectively solve technical problems that wheel speed signals are only used as input signals of an existing electronic mechanical brake (EMB) system, an EMB cannot judge the running status of a vehicle once a wheel speed sensor is failed, consequentially, the system is failed and cannot control the vehicle, accidents are caused in severe situations, and the like. The detection and control system in the technical scheme is accurate and speedy in detection and control, low in cost and long in service life, and relevant parts operate stably.

Description

A kind ofly be applied to Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system

Technical field

The utility model belongs to self-propelled vehicle security fields Detection ﹠ Controling method, specifically, relates to the Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to.

Background technology

Along with consumers in general more and more pay attention to vehicle safety, the brake system of power actuated vehicle has also been gone through transition for several times and improvement.Drum-type, plate disc brake appear in leather friction braking from initial finally, occur mechanical type abs braking system more finally, and then follow development of electronic technology to occur simulation electronic abs braking system, electrically controlled digital abs braking system or the like again.At present, development along with technology, some producers begin electric mechanical braking device (Electro-mechanicalBrake) is begun to study and put into practice, simple electric mechanical braking device (EMB) is exactly the part of former cause hydraulic pressure or compressed air-driven to be changed into by electrical motor drive, so as to improving speed of response, increasing brake efficiency etc., also simplified the structure, reduced simultaneously the difficulty of I﹠ M greatly.

The parts such as hydraulic tubing in the former brake system have been abandoned by electric mechanical braking device (EMB) system, and the source that directly produces as braking force with electric energy.Compare with traditional hydraulic brake system, electric mechanical braking device (EMB) system transmits signal and energy with wire harness, can improve the speed of response of brake operating, shortens stopping distance; And can integrated easily ABS, multiple functions such as ESP, TCS, need not other annexes of additive incrementation; Electric mechanical braking device (EMB) system architecture is succinct, has reduced the difficulty of I﹠ M, helps the layout of car load; Replace traditional mechanical pedal force transmitters with pedal simulator,, improved the feel of glancing impact, and do not have the phenomenon of pinching with the intention of electric signal transmission chaufeur; Do not need braking liquid, avoided pollution environment.Electric mechanical braking device (EMB) is one of mode of line control brake system, and line control brake system is the main contents of automotive line control techniques.Along with the development of automotive line control techniques, electric mechanical braking device (EMB) system also will progressively replace traditional hydraulic brake system, becomes the main flow mode of following brake system of car.

For the mechanical actuating mechanism of electric mechanical braking device (EMB) system, it directly accepts the moment that electrical motor produces, and amplification is to brake disc, and its structure should satisfy following several basic requirement: compact conformation, be convenient to arrange; Can be converted into translation to rotation; Having slows down increases square, self energizing effort mechanism; Can the automatic compensation brake clearance; Braking during standstill when stopping can be provided; Safe and reliable, work-hours is long.In electric mechanical braking device (EMB) system, wheel speed signal is an indispensable important input parameter.System obtains wheel speed signal by wheel speed sensors, or obtains wheel speed signal by CAN communication from other system (as ABS, ESP etc.).By wheel speed signal, system can calculate current vehicle speed, judge whether locking of wheel, important information such as whether trackslip, and takes corresponding control measures in view of the above.

Along with the continuous application of electric mechanical braking device (EMB) system on vehicle, the vehicle that this system is installed will inevitably face following technical matters:

Because electric mechanical braking device of the prior art (EMB) system adopts wheel speed signal as initial conditions, after in case wheel speed sensors breaks down, or after the CAN communication module of transmitting wheel speed signal breaks down, promptly, in case lose wheel speed signal, travel condition of vehicle can't be judged by system, and then cause thrashing, can't control vehicle, will lead to a disaster when serious.

The utility model content

The technical scheme that the utility model provides technical matters to be solved is, because existing electric mechanical braking device (EMB) system relies on wheel speed signal as unique incoming signal, after in case wheel speed sensors breaks down, or after the CAN communication module of transmitting wheel speed signal breaks down, travel condition of vehicle can't be judged by electric mechanical braking device system, and then cause thrashing, can't control vehicle, technical matters such as will lead to a disaster when serious, and provide a kind of after wheel speed signal lost efficacy, to adopt other actv. detection and control method more, the control method that vehicle is controlled, that is Detection ﹠ Controling system in a kind of motor vehicle electronic mechanical brake system.

Design of the present utility model is, after wheel speed sensors breaks down, or after the CAN communication module of transmitting wheel speed signal breaks down, not therefore electric mechanical braking device (EMB) system can be and cisco unity malfunction, but discern travel condition of vehicle by acceleration pick-up and yaw-rate sensor, guarantee that ECU still can detect travel condition of vehicle and control brake system and take appropriate measures and adjust the attitude of travelling of vehicle under dangerous situation, prevent accidents such as whipping, rollover.

Technical scheme provided by the utility model is, a kind ofly be applied to Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system, described Detection ﹠ Controling system comprises electronic control unit, be provided with acceleration pick-up and yaw-rate sensor in the described electronic control unit, described acceleration pick-up is connected by signal line with described electronic control unit respectively with described yaw-rate sensor; Described acceleration pick-up is a 3-axis acceleration sensor, comprises X-axis acceleration detection, Y-axis acceleration detection and Z axle acceleration detection; Described electronic control unit links to each other with other control module by the CAN communication module; Between described electronic control unit and the described CAN communication module, and be two-way signaling and be connected between the described CAN communication module with between other control module; Described electronic control unit links to each other with wheel by wheel speed sensors; Described electronic control unit links to each other with wheel by actuating unit.

Adopt technical scheme provided by the utility model, can effectively solve existing electric mechanical braking device (EMB) system relies on wheel speed signal as unique incoming signal, after in case wheel speed sensors breaks down, or after the CAN communication module of transmitting wheel speed signal breaks down, travel condition of vehicle can't be judged by electric mechanical braking device system, and then cause thrashing, can't control vehicle, technical matters such as will lead to a disaster when serious, simultaneously, the technical scheme Detection ﹠ Controling that provide of the utility model are accurate, fast, the related parts working stability of this method, cost is low, long service life.

Description of drawings

Fig. 1 is that the utility model electric mechanical braking device (EMB) system forms principle schematic;

Fig. 2 is vehicle acceleration due to gravity decomposing schematic representation on sloping road;

Fig. 3 is the vehicle running state decision flow chart;

Fig. 4 is at the uniform velocity or the quiescence decision flow chart;

Wherein, 1 is electronic control unit; 2 is acceleration pick-up; 3 is yaw-rate sensor; 4 is wheel speed sensors; 5 is actuating unit; 6 is wheel; 7 is the CAN communication module; 8 is other control module.

The specific embodiment

Technical scheme provided by the utility model, after being based on wheel speed sensors 4 and breaking down, or after CAN communication module 7 modules of transmitting wheel speed signal break down, electric mechanical braking device (EMB) system can be not therefore and cisco unity malfunction.After in case the CAN communication module 7 of wheel speed sensors 4 or transmission wheel speed signal breaks down, electric mechanical braking device (EMB) system switches to wheel speed sensors 4 Failure Control patterns at once, discern travel condition of vehicle by acceleration pick-up 2 and yaw-rate sensor 3, guarantee that ECU still can detect travel condition of vehicle and control brake system and take appropriate measures and adjust the attitude of travelling of vehicle under dangerous situation, prevent accidents such as whipping, rollover.

The connection mode of technical scheme that the utility model provides is that four wheels 6 are connected with wheel speed sensors 4 with actuating unit 5 respectively; Described actuating unit 5 is connected with described electronic control unit 1 (ECU) respectively with described wheel speed sensors 4, and described electron steering power supply also is connected with CAN communication module 7, and described CAN communication module 7 other ends are connected with other control module 8.

Technical scheme provided by the utility model is, a kind ofly be applied to Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system, described Detection ﹠ Controling system comprises electronic control unit 1 (ECU), be provided with acceleration pick-up 2 and yaw-rate sensor 3 in the described electronic control unit 1 (ECU), described acceleration pick-up 2 is connected by signal line with described electronic control unit 1 (ECU) respectively with described yaw-rate sensor 3; Described acceleration pick-up 2 is a 3-axis acceleration sensor 2, comprises X-axis acceleration detection, Y-axis acceleration detection and Z axle acceleration detection; Described electronic control unit 1 (ECU) links to each other with other control module 8 by CAN communication module 7; Between described electronic control unit 1 (ECU) and the described CAN communication module 7, and be two-way signaling and be connected between the described CAN communication module 7 with between other control module 8; Described electronic control unit 1 (ECU) links to each other with wheel 6 by wheel speed sensors 4; Described electronic control unit 1 (ECU) links to each other with wheel 6 by actuating unit 5.

A kind ofly be applied to Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system, in the electronic control unit 1 (ECU) of described self-propelled vehicle, be provided with acceleration pick-up 2 and yaw-rate sensor 3, described electronic control unit 1 (ECU) receives the signal information that transmits from described acceleration pick-up 2 and described yaw-rate sensor 3, and described electronic control unit 1 (ECU) is judged information such as the current motoring condition of vehicle, the estimation speed of a motor vehicle by described acceleration pick-up 2; Described electronic control unit 1 (ECU) judges by described yaw-rate sensor 3 whether vehicle information such as whipping, inclination take place.Described electronic control unit 1 (ECU) is judged comparison with information such as above-mentioned motoring condition, the estimation speed of a motor vehicle, whipping, inclination and standard value; When judging automobile storage in dangerous operating modes such as inclination, whippings, described electronic control unit 1 (ECU) sends instruction to actuating unit 5, by 5 pairs of brake wheel brake activationes of described actuating unit power.

This method is: an integrated acceleration pick-up 2 and a yaw-rate sensor 3 in ECU, like this, when wheel speed sensors 4 or the time after CAN communication module 7 lost efficacy, system discerns travel condition of vehicle by acceleration pick-up 2 and yaw-rate sensor 3, comprise the current motoring condition of vehicle, the estimation speed of a motor vehicle, judge whether vehicle whipping, inclination take place, when finding that vehicle has dangerous operating mode such as inclination, whipping, apply different braking forces by 5 pairs of corresponding brake wheels of ECU control executing mechanism, thereby avoid the generation of accident.

Described acceleration pick-up 2 is a 3-axis acceleration sensor 2, comprises X-axis acceleration detection, Y-axis acceleration detection and Z axle acceleration detection; Described electronic control unit 1 (ECU) judges that by acceleration pick-up 2 method of vehicle running state is:

Described electronic control unit 1 (ECU) is at first judged described acceleration pick-up 2Z axle acceleration value, if Z axle acceleration value equals gravity acceleration value, then is judged as vehicle at the level road state; If Z axle acceleration value less than gravity acceleration value, then is judged as vehicle at sloping line state.

Described judgement vehicle is when the level road state, and described electronic control unit 1 (ECU) is judged described acceleration pick-up 2X axle acceleration value, if the X-axis accekeration is being for just, then vehicle is at the state of giving it the gun; If the X-axis accekeration is for negative, then vehicle is at the Reduced Speed Now state; If the X-axis accekeration is zero, then vehicle is at the uniform velocity travelling or quiescence.

Described judgement vehicle is when sloping line state, and described electronic control unit 1 (ECU) is judged described acceleration pick-up 2X axle acceleration value, and greater than the component of acceleration due to gravity along X-direction, then vehicle is at the state of giving it the gun as if the X-axis accekeration; If the X-axis accekeration is less than the component of acceleration due to gravity along X-direction, then vehicle is at the Reduced Speed Now state; If the X-axis accekeration equals the component of acceleration due to gravity along X-direction, then vehicle is at the uniform velocity travelling or quiescence.

When described X-axis accekeration is zero, judge that it still is that the method for quiescence is that vehicle is in motoring condition at the uniform velocity, apply an of short duration braking force by 5 pairs of wheels 6 of electronic control unit 1 (ECU) control executing mechanism, judge according to the X-axis accekeration during this braking then:

Under the level road state, if described acceleration pick-up 2X axle acceleration value still equals zero, then vehicle remains static; If described acceleration pick-up 2X axle acceleration value is for negative, then vehicle is at the uniform velocity motoring condition;

Under sloping line state, if acceleration due to gravity still equals zero along the axial component of described acceleration pick-up 2X, then vehicle remains static; If described acceleration pick-up 2X axle acceleration value is for negative, then vehicle is at the uniform velocity motoring condition.

Described electronic control unit 1 (ECU) utilizes the method for the acceleration pick-up 2 estimation speed of a motor vehicle to be: gather described acceleration pick-up 2X axle acceleration value, by the method for integration, obtain current vehicle speed.The specific algorithm of described integration is:

With the X-axis acceleration/accel discrete value that collects be made as { a (k) } (k=0,1,2 ..., N), then speed of a motor vehicle v (k) is:

$v\left(k\right)=\mathrm{\Δt}\underset{i=1}{\overset{k}{\mathrm{\Σ}}}\frac{a(i-1)+a\left(i\right)}{2}---\left(1\right)$

In the following formula:

V (k)---the speed of a motor vehicle of k sampling point, m/s;

Δ t---sampling time interval, s.

Described electronic control unit 1 (ECU) judges by acceleration pick-up 2 and yaw-rate sensor 3 whether vehicle has the method for whipping, inclination to be, when vehicle during at cruising or turn condition:

If described acceleration pick-up 2Y axle acceleration value variation range is in standard value, simultaneously, the detected deflection angle along the deflection of automobile vertical axis of described yaw-rate sensor 3 is in standard value, and then vehicle is in the cruising state;

If described acceleration pick-up 2Y axle acceleration value variation range is beyond standard value, simultaneously, the detected deflection angle along the deflection of automobile vertical axis of described yaw-rate sensor 3 is beyond standard value, and then vehicle is in and breaks away or the dangerous operating mode of whipping.

Whether discern vehicle by acceleration pick-up 2 and yaw-rate sensor 3 has the method for whipping, inclination to be: when vehicle at cruising, when turning, the Y-axis accekeration changes very little, in standard value; But as whipping, when inclination takes place, then the Y-axis accekeration changes greatly, beyond standard value.Utilize yaw-rate sensor 3 to detect along the deflection of automobile vertical axis again, the size of this deflection has been represented the degree of stability of vehicle traveling direction.If deflection angle less than a certain threshold value, promptly in standard value, then illustrates the vehicle safety travel operating mode.If deflection angle greater than a certain threshold value, promptly beyond standard value, illustrates that then the dangerous operating mode of sideslip or whipping takes place automobile.

Comprehensive above information, the running state that vehicle is current just can be learnt by system.Like this, when dangerous situation took place, ECU applied different braking forces by 5 pairs of corresponding brake wheels of control executing mechanism and adjusts the vehicle body attitude of travelling, thereby prevents accidents such as whipping, rollover; Simultaneously, can also reduce moment of torsion output, further guarantee driving safety by CAN communication module 7 notice control unit of engine.

In the technical scheme provided by the utility model, the utility model point that highlights is, in case after the CAN communication module 7 of wheel speed sensors 4 or transmission wheel speed signal broke down, electric mechanical braking device (EMB) system switched to wheel speed sensors 4 Failure Control patterns at once;

At first, judge the motoring condition that vehicle is current by acceleration pick-up 2X axle acceleration signal.On level road, acceleration pick-up 2X axle acceleration is the acceleration/accel that travels of vehicle, but on sloping road, acceleration pick-up 2X axle acceleration also can be subjected to the influence of gravitational acceleration component, as shown in Figure 2: gather acceleration pick-up 2Z axle acceleration value α _Z, if α _Z=G (acceleration due to gravity) illustrates that then vehicle is on level road; If α _Z＜G then illustrates vehicle on sloping road, and this moment can be according to α _ZCalculate grade angle

:

$\∂=\arccos \left(\frac{a_Z}{G}\right)---\left(1\right)$

And then calculate the component α of acceleration due to gravity G along X-direction _GX:

${\mathrm{\α}}_{\mathrm{GX}}=G\×\sin \∂---\left(2\right)$

Further, if vehicle on level road, is judged X-axis accekeration α _XIf just, illustrating that then vehicle is giving it the gun; If negative, illustrate that then vehicle is in Reduced Speed Now; If zero, illustrate that then vehicle is at the uniform velocity travelling or quiescence.If vehicle on sloping road, is judged α _XIf value is a _X＞α _GX, illustrate that then vehicle is giving it the gun; If a _X＜α _GX, illustrate that then vehicle is in Reduced Speed Now; If a _X=α _GX, illustrate that then vehicle is at the uniform velocity travelling or quiescence.Decision flow chart as shown in Figure 3.

If judge vehicle at the uniform velocity travelling or quiescence, then can further determine it: apply an of short duration braking force by 5 pairs of wheels 6 of ECU control executing mechanism by flow process shown in Figure 4, and gather acceleration pick-up 2X axle acceleration value during this period, if negative, illustrate that then vehicle is at the uniform velocity motoring condition; If still be zero, illustrate that then vehicle remains static.

Secondly, by acceleration pick-up 2X axle acceleration value estimation current vehicle speed, specific algorithm is as follows: establish the acceleration pick-up 2X axle acceleration discrete value that collects for { a (k) } (k=0,1,2 ..., N), then the speed of a motor vehicle can be expressed as:

$v\left(k\right)=\mathrm{\Δt}\underset{i=1}{\overset{k}{\mathrm{\Σ}}}\frac{a(i-1)+a\left(i\right)}{2}---\left(3\right)$

In the following formula:

V (k)---the speed of a motor vehicle of k sampling point, m/s;

Δ t---sampling time interval, s.

Once more, discern vehicle by acceleration pick-up 2 and yaw-rate sensor 3 whether whipping, inclination arranged: when vehicle at cruising, when turning, acceleration pick-up 2Y axle acceleration value changes very little, but as whipping, when inclination takes place, then acceleration pick-up 2Y axle acceleration value changes greatly.Utilize yaw-rate sensor 3 to detect along the deflection of automobile vertical axis again, the size of this deflection has been represented the degree of stability of vehicle traveling direction.If deflection angle, then illustrates automobile greater than a certain threshold value the dangerous operating mode of sideslip or whipping takes place.

At last, information such as comprehensive vehicle running state, the speed of a motor vehicle and inclination, whipping are judged: if vehicle is in high-speed travel state and there is dangerous operating mode such as whipping, inclination to take place, then apply different braking forces respectively by 5 pairs of corresponding brake wheels of control executing mechanism and adjust the vehicle body attitude of travelling by ECU, can also reduce moment of torsion output by CAN communication module 7 notice control unit of engine simultaneously, thereby prevent accidents such as whipping, rollover.

This method is directed to that wheel speed sensors 4 in electric mechanical braking device (EMB) system breaks down or CAN communication module 7 modules of transmitting wheel speed signal break down back with failure detection and control method, but this method is not limited only in electric mechanical braking device (EMB) system, in other chassis control systems, as ABS, TCS is suitable in the systems such as ESP too.

Although above the specific embodiment of the present utility model is described; but the utility model is not limited to the above-mentioned specific embodiment; the above-mentioned specific embodiment only is schematic; rather than it is restrictive; those skilled in the art is under enlightenment of the present utility model; under the situation that does not break away from the utility model aim, can also make a lot of distortion, these all belong to protection domain of the present utility model.

Claims (7)

1. one kind is applied to Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system, it is characterized in that, described Detection ﹠ Controling system comprises electronic control unit (1), be provided with acceleration pick-up (2) and yaw-rate sensor (3) in the described electronic control unit (1), described acceleration pick-up (2) is connected by signal line with described electronic control unit (1) respectively with described yaw-rate sensor (3).

2. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 1, it is characterized in that, described acceleration pick-up (2) is 3-axis acceleration sensor (2), comprises X-axis acceleration detection, Y-axis acceleration detection and Z axle acceleration detection.

3. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 1 and 2 is characterized in that, described electronic control unit (1) links to each other with other control module (8) by CAN communication module (7).

4. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 3, it is characterized in that, between described electronic control unit (1) and the described CAN communication module (7), and be two-way signaling and be connected between the described CAN communication module (7) with between other control module (8).

5. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 4 is characterized in that, described electronic control unit (1) links to each other with wheel (6) by wheel speed sensors (4);

6. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 5 is characterized in that, described electronic control unit (1) links to each other with wheel (6) by actuating unit (5).

7. a kind of Detection ﹠ Controling system in the motor vehicle electronic mechanical brake system that is applied to according to claim 6, it is characterized in that, when described electronic control unit (1) judges that vehicle is in the dangerous operating mode of sideslip or whipping, described electronic control unit (1) applies different braking forces by control executing mechanism (5) to corresponding brake wheel and adjusts the vehicle body attitude of travelling, and prevents vehicle whipping, rollover; Simultaneously, described electronic control unit (1) also reduces moment of torsion output by vehicle CAN communication module (7) notice control unit of engine.

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