Auxiliary braking method and device for vehicle

文档序号:1093188 发布日期:2020-09-25 浏览:12次 中文

阅读说明:本技术 车辆的辅助制动方法和装置 (Auxiliary braking method and device for vehicle ) 是由 李熙 石仲伟 马路路 孟祥禄 郝之凯 邢东伟 陈聪 陈美健 孙玉 徐波 张英富 于 2020-06-09 设计创作,主要内容包括:本发明涉及车辆控制技术领域,提供一种车辆的辅助制动方法和装置。该方法包括:实时检测所述车辆的制动主缸建立的压力;实时检测制动储液壶的液位;在所述车辆的制动踏板被踩下时,检测所述制动踏板的位移;根据所检测的制动踏板的位移、所检测的制动主缸建立的压力和/或所检测的储液壶的液位,控制所述车辆的电子稳定系统或电子驻车制动系统进行辅助制动。本发明可以在制动系统性能下降或者失效时及时控制辅助制动,保证车辆的安全行驶。(The invention relates to the technical field of vehicle control, and provides an auxiliary braking method and device for a vehicle. The method comprises the following steps: detecting pressure established by a brake master cylinder of the vehicle in real time; detecting the liquid level of the brake liquid storage pot in real time; detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed; and controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot. The invention can control the auxiliary brake in time when the performance of the brake system is reduced or the brake system is invalid, thereby ensuring the safe driving of the vehicle.)

1. An auxiliary braking method for a vehicle, characterized in that the method comprises:

detecting pressure established by a brake master cylinder of the vehicle in real time;

detecting the liquid level of the brake liquid storage pot in real time;

detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed;

and controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

2. The auxiliary braking method of a vehicle according to claim 1, wherein the controlling of the electronic stability system or the electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the master cylinder, and/or the detected liquid level of the reservoir pot includes:

determining the pressure building time of the brake master cylinder according to the detected pressure built by the brake master cylinder;

determining the variation of the liquid level according to the detected liquid level of the liquid storage kettle;

determining preset time of the pressure building time and preset variable quantity of the liquid level according to the detected displacement of the brake pedal;

and when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking.

3. The auxiliary braking method of a vehicle according to claim 2, wherein the determining the preset time of the pressure buildup time and the preset variation amount of the liquid level according to the detected displacement of the brake pedal includes:

determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time;

determining a previous pressure buildup time of the master cylinder corresponding to a previous displacement of the brake pedal identical to the detected displacement of the brake pedal and a previous amount of change in the liquid level, as a preset time of the pressure buildup time and a preset amount of change in the liquid level.

4. The auxiliary braking method of a vehicle according to claim 1, wherein the controlling of the electronic stability system or the electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the master cylinder, and/or the detected liquid level of the reservoir pot includes:

determining a build-up pressure demand based on the detected displacement of the brake pedal;

and when the detected pressure built by the brake master cylinder is less than the pressure building requirement, controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking.

5. The auxiliary braking method of a vehicle according to claim 1, characterized in that the method further comprises:

detecting a vacuum level of a vacuum booster of the vehicle;

and when the vacuum degree is smaller than the preset vacuum degree, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking.

6. An auxiliary braking device for a vehicle, characterized in that it comprises:

a detection unit and a control unit, wherein,

the detection unit is used for:

detecting pressure established by a brake master cylinder of the vehicle in real time;

detecting the liquid level of the brake liquid storage pot in real time;

detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed;

the control unit is used for controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

7. The auxiliary brake apparatus of a vehicle according to claim 6, wherein the control unit is further configured to:

determining the pressure building time of the brake master cylinder according to the detected pressure built by the brake master cylinder;

determining the variation of the liquid level according to the detected liquid level of the liquid storage kettle;

determining preset time of the pressure building time and preset variable quantity of the liquid level according to the detected displacement of the brake pedal;

and when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking.

8. The auxiliary braking method of a vehicle according to claim 7, characterized in that the control unit is further configured to:

determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time;

determining a previous pressure buildup time of the master cylinder corresponding to a previous displacement of the brake pedal identical to the detected displacement of the brake pedal and a previous amount of change in the liquid level, as a preset time of the pressure buildup time and a preset amount of change in the liquid level.

9. The auxiliary brake apparatus of a vehicle according to claim 6, wherein the control unit is further configured to:

determining a build-up pressure demand based on the detected displacement of the brake pedal;

and when the detected pressure built by the brake master cylinder is less than the pressure building requirement, controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking.

10. The auxiliary braking device of a vehicle according to claim 6,

the detection unit is also used for detecting the vacuum degree of a vacuum booster of the vehicle;

the control unit is further used for controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking when the vacuum degree is smaller than a preset vacuum degree.

Technical Field

The invention relates to the technical field of vehicle control, in particular to an auxiliary braking method and device for a vehicle.

Background

Safety of the vehicle, especially of the brake system, is particularly important. At present, when the performance of a brake system is reduced or fails, for example, the pressure relief of the brake system is leaked, the vacuum seal of a booster system is failed, the oil leakage of the booster system is failed, the failure of a rear pipeline is failed, the leakage is failed, and the like, the reduction of related performance cannot be timely identified by a vehicle at present, corresponding actions cannot be timely and effectively taken, and the personal safety of a driver and passengers in the vehicle is endangered.

Disclosure of Invention

In view of the above, the present invention is directed to provide an auxiliary braking method for a vehicle, so as to control auxiliary braking in time when a braking system is degraded or fails, thereby ensuring safe driving of the vehicle.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a method of auxiliary braking of a vehicle, the method comprising: detecting pressure established by a brake master cylinder of the vehicle in real time; detecting the liquid level of the brake liquid storage pot in real time; detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed; and controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

Further, the controlling the electronic stability system or the electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot comprises: determining the pressure building time of the brake master cylinder according to the detected pressure built by the brake master cylinder; determining the variation of the liquid level according to the detected liquid level of the liquid storage kettle; determining preset time of the pressure building time and preset variable quantity of the liquid level according to the detected displacement of the brake pedal; and when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking.

Further, the determining the preset time of the pressure buildup time and the preset variation of the liquid level according to the detected displacement of the brake pedal includes: determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time; determining a previous pressure buildup time of the master cylinder corresponding to a previous displacement of the brake pedal identical to the detected displacement of the brake pedal and a previous amount of change in the liquid level, as a preset time of the pressure buildup time and a preset amount of change in the liquid level.

Further, the controlling the electronic stability system or the electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot comprises: determining a build-up pressure demand based on the detected displacement of the brake pedal; and when the detected pressure built by the brake master cylinder is less than the pressure building requirement, controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking.

Further, the method further comprises: detecting a vacuum level of a vacuum booster of the vehicle; and when the vacuum degree is smaller than the preset vacuum degree, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking.

Compared with the prior art, the auxiliary braking method for the vehicle has the following advantages:

firstly, detecting the pressure established by a brake master cylinder of the vehicle in real time and detecting the liquid level of a brake liquid storage pot in real time; and then detecting the displacement of the brake pedal when the brake pedal of the vehicle is stepped, and finally controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot. Therefore, the performance reduction or failure of the brake system can be detected, and the auxiliary brake can be controlled in time when the performance reduction or failure of the brake system occurs, so that the safe running of the vehicle is ensured.

Another object of the present invention is to provide an auxiliary brake device for a vehicle, which can control the auxiliary brake in time when the performance of the brake system is reduced or fails, so as to ensure the safe driving of the vehicle

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

an auxiliary braking device for a vehicle, the device comprising: the device comprises a detection unit and a control unit, wherein the detection unit is used for: detecting pressure established by a brake master cylinder of the vehicle in real time; detecting the liquid level of the brake liquid storage pot in real time; detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed; the control unit is used for controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

Further, the control unit is further configured to: determining the pressure building time of the brake master cylinder according to the detected pressure built by the brake master cylinder; determining the variation of the liquid level according to the detected liquid level of the liquid storage kettle; determining preset time of the pressure building time and preset variable quantity of the liquid level according to the detected displacement of the brake pedal; and when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking.

Further, the control unit is further configured to: determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time; determining a previous pressure buildup time of the master cylinder corresponding to a previous displacement of the brake pedal identical to the detected displacement of the brake pedal and a previous amount of change in the liquid level, as a preset time of the pressure buildup time and a preset amount of change in the liquid level.

Further, the control unit is further configured to: determining a build-up pressure demand based on the detected displacement of the brake pedal; and when the detected pressure built by the brake master cylinder is less than the pressure building requirement, controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking.

Further, the detection unit is also used for detecting the vacuum degree of a vacuum booster of the vehicle; the control unit is further used for controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking when the vacuum degree is smaller than a preset vacuum degree.

Compared with the prior art, the auxiliary braking device of the vehicle and the auxiliary braking method of the vehicle have the same advantages, and the detailed description is omitted.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In the drawings:

FIG. 1 is a flow chart of a method of assisting braking of a vehicle according to an embodiment of the present invention;

FIG. 2 is a flow chart of a method of assisting braking of a vehicle provided by another embodiment of the present invention;

fig. 3 is a flowchart of a method for determining a preset time and a preset variation according to an embodiment of the present invention;

FIG. 4 is a flow chart of a method of assisting braking of a vehicle provided by another embodiment of the present invention;

FIG. 5 is a flow chart of a method of assisting braking of a vehicle provided by another embodiment of the present invention;

fig. 6 is a block diagram showing a configuration of an auxiliary brake device for a vehicle according to an embodiment of the present invention.

Description of reference numerals:

1 detection unit 2 control unit.

Detailed Description

In addition, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Fig. 1 is a flowchart of an auxiliary braking method for a vehicle according to an embodiment of the present invention. As shown in fig. 1, the method includes:

step S11, detecting the pressure built by the brake master cylinder of the vehicle in real time;

specifically, the magnitude of the pressure established by the master cylinder may be detected in real time using the master cylinder pressure sensor.

Step S12, detecting the liquid level of the brake liquid storage pot in real time;

in particular, the liquid level of the brake reservoir can be detected in real time using a reservoir displacement sensor.

Step S13, detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed;

specifically, when the driver depresses the brake pedal, a change in displacement of the brake pedal may be detected using the pedal displacement sensor at this time.

And step S14, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

Specifically, based on the detected pressure established by the master cylinder, the liquid level of the liquid storage pot and/or the displacement of the brake pedal when the brake pedal is pressed, the following two methods can be judged:

first, as shown in fig. 2, the method includes:

step S21, determining the pressure build-up time of the brake master cylinder according to the detected pressure built up by the brake master cylinder;

specifically, the time taken for the master cylinder to build pressure (assuming that the master cylinder can build pressure corresponding to the displacement of the brake pedal, the master cylinder build pressure is complete, that is, the pressure built by the master cylinder reaches the pressure corresponding to the displacement of the pedal) can be determined by the cpu.

Step S22, determining the variation of the liquid level according to the detected liquid level of the liquid storage pot;

specifically, the central processing unit can judge how much the liquid level of the liquid storage pot changes after the brake pedal is stepped on.

Step S23, determining the preset time of the pressure building time and the preset variable quantity of the liquid level according to the detected displacement of the brake pedal;

specifically, in the same vehicle, the pressure buildup time and the amount of change in the liquid level corresponding to the displacement of the brake pedal are fixed and known, and therefore, the amount of change in the pressure buildup time and the liquid level corresponding thereto can be read directly from the displacement of the brake pedal as the preset time and the preset amount of change.

In addition, if some components of the vehicle that do not affect the brake system have a fault, resulting in a small change in the actual preset time and preset variation from the known preset time and preset variation, it is possible to misjudge whether the brake system is faulty. Therefore, an embodiment of the present invention further provides a method for obtaining a preset time and a preset variation, as shown in fig. 3, where the method includes:

step S31 of determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time;

specifically, the brake pedal should have been depressed multiple times before the brake pedal is depressed this time, and since the pressure buildup time of the master cylinder and the amount of change in the liquid level are recorded in real time, the previous displacement of the brake pedal when the brake pedal was depressed before, the previous pressure buildup time of the master cylinder, and the previous amount of change in the liquid level are all known.

Step S32, determining a previous pressure buildup time of the master cylinder and a previous variation amount of the liquid level corresponding to a previous displacement of the brake pedal that is the same as the detected displacement of the brake pedal, as a preset time of the pressure buildup time and a preset variation amount of the liquid level.

Specifically, since the displacement of the brake pedal and the pressure buildup time (or the amount of change in the liquid level) of the master cylinder are not strictly linear and proportional, the embodiment of the present invention compares the previous pressure buildup time of the master cylinder with the previous amount of change in the liquid level in the case of the same displacement. That is, if the displacement of the previous multiple-time depression of the brake pedal is exactly the same as the currently detected displacement of the brake pedal, the previous pressure buildup time and the previous variation amount of the liquid level of the brake master cylinder corresponding thereto may be directly used as the preset time and the preset variation amount, and if the displacement of the previous multiple-time depression of the brake pedal is not the same as the currently detected displacement of the brake pedal, the previous variation amount of the pressure buildup time and the liquid level of the brake master cylinder corresponding to the currently detected displacement of the brake pedal may be found as the preset time and the preset variation amount from the previous multiple-time depression of the brake pedal greater than the currently detected displacement of the brake pedal. Of course, for more accuracy, the previous pressure buildup time and the previous variation amount of the liquid level of the master cylinder may be averaged for a plurality of times (e.g., 3 times) as the preset time and the preset variation amount.

Step S24, judging whether the pressure building time is larger than a preset time and whether the liquid level variation is smaller than a preset variation;

and step S25, when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking.

And step S26, when the pressure building time is not more than the preset time or the variation of the liquid level is not less than the preset variation, the control is not carried out.

Specifically, if the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, normal braking cannot be performed, and at this time, the ESP can be immediately controlled to actively increase the wheel cylinder pressure or the EPB assist can be controlled to rapidly increase the vehicle deceleration so as to ensure safe braking of the vehicle. In addition, because the brake system has efficiency loss, if the driver does not have a leakage phenomenon in subsequent detection, the central controller can take the currently obtained pressure building time and the liquid level variable quantity as the preset pressure building time and the preset variable quantity.

Secondly, as shown in fig. 4, the method includes:

step S41, determining a pressure build-up demand according to the detected displacement of the brake pedal;

specifically, the piston of the master cylinder (brake master cylinder) of the vacuum booster causes damage of a sealing ring due to impurities or abnormal abrasion, so that hydraulic leakage cannot form boosting, namely, oil leakage of a boosting system fails, and finally, the operating force of a driver is increased, the emergency working condition cannot quickly reach the expected deceleration, and at the moment, when a brake pedal is stepped on, the brake master cylinder cannot establish corresponding pressure. Or the rear line fails, in which case the master cylinder is likewise unable to build up a corresponding pressure when the brake pedal is depressed. Thus, the driver's build-up pressure needs to be available first, and the displacement of the brake pedal can reflect the driver's need for the master cylinder to build up pressure.

Step S42, judging whether the pressure established by the detected brake master cylinder is smaller than the pressure establishment requirement;

and step S43, when the pressure built by the detected brake master cylinder is smaller than the pressure building requirement, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking.

In step S44, when the detected pressure built up by the master cylinder is not less than the pressure build-up demand, no control is performed.

Specifically, if the pressure established by the brake master cylinder is smaller than the pressure establishment requirement, normal braking cannot be performed, the vehicle cannot reach the expected deceleration or even cannot decelerate, and at the moment, the ESP can be immediately controlled to actively increase the wheel cylinder pressure, or the EPB assist is controlled to rapidly increase the vehicle deceleration, so that the safe braking of the vehicle is ensured. After the brake, can light danger indicator, the suggestion is peripheral navigating mate, guarantees the safety of vehicle.

Fig. 5 is a flowchart of an auxiliary braking method for a vehicle according to another embodiment of the present invention. As shown in fig. 5, the method includes:

step S51, detecting the vacuum degree of the vacuum booster of the vehicle;

specifically, the failure of the vacuum seal caused by the breakage of the sealing valve of the vacuum booster leads to the increase of the operating force of the driver, and the emergency condition cannot quickly reach the expected deceleration. For this, the vacuum degree of the vacuum booster may be first detected using a vacuum degree sensor.

Step S52, judging whether the vacuum degree is less than the preset vacuum degree;

and step S53, when the vacuum degree is smaller than the preset vacuum degree, controlling an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking.

And step S54, when the vacuum degree is not less than the preset vacuum degree, not controlling.

Specifically, if the detected vacuum degree is less than the preset vacuum degree, which indicates that the vacuum degree is invalid, normal braking cannot be performed, and the vehicle cannot reach the expected deceleration or even cannot decelerate, at this time, the ESP can be immediately controlled to actively increase the wheel cylinder pressure, or the EPB assist is controlled to rapidly increase the vehicle deceleration, so that the vehicle safety brake is ensured.

Fig. 6 is a block diagram showing a configuration of an auxiliary brake device for a vehicle according to an embodiment of the present invention. As shown in fig. 6, the apparatus includes: a detection unit 1 and a control unit 2, wherein the detection unit 1 is used for: detecting pressure established by a brake master cylinder of the vehicle in real time; detecting the liquid level of the brake liquid storage pot in real time; detecting a displacement of a brake pedal of the vehicle when the brake pedal is depressed; the control unit 2 is used for controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking according to the detected displacement of the brake pedal, the detected pressure established by the brake master cylinder and/or the detected liquid level of the liquid storage pot.

Further, the control unit 2 is further configured to: determining the pressure building time of the brake master cylinder according to the detected pressure built by the brake master cylinder; determining the variation of the liquid level according to the detected liquid level of the liquid storage kettle; determining preset time of the pressure building time and preset variable quantity of the liquid level according to the detected displacement of the brake pedal; and when the pressure building time is greater than the preset time and the variation of the liquid level is less than the preset variation, controlling an electronic stabilizing system or an electronic parking braking system of the vehicle to perform auxiliary braking.

Further, the control unit 2 is further configured to: determining a previous displacement of the brake pedal, a previous pressure buildup time of the master cylinder, and a previous variation amount of the liquid level when the brake pedal is depressed a plurality of times before the brake pedal is depressed this time; determining a previous pressure buildup time of the master cylinder corresponding to a previous displacement of the brake pedal identical to the detected displacement of the brake pedal and a previous amount of change in the liquid level, as a preset time of the pressure buildup time and a preset amount of change in the liquid level.

Further, the control unit 2 is further configured to: determining a build-up pressure demand based on the detected displacement of the brake pedal; and when the detected pressure built by the brake master cylinder is less than the pressure building requirement, controlling an electronic stabilizing system or an electronic parking brake system of the vehicle to perform auxiliary braking.

Further, the detection unit 1 is also used for detecting the vacuum degree of a vacuum booster of the vehicle; the control unit 2 is further configured to control an electronic stability system or an electronic parking brake system of the vehicle to perform auxiliary braking when the vacuum degree is less than a preset vacuum degree.

The above-described auxiliary braking device for a vehicle is similar to the above-described embodiment of the auxiliary braking method for a vehicle, and thus, the detailed description thereof is omitted.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

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