CN112141079A - Hydraulic control method and storage medium for follow-up brake stopping - Google Patents
Hydraulic control method and storage medium for follow-up brake stopping Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
- B60W30/18—Propelling the vehicle
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- B60W30/18109—Braking
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
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- B60—VEHICLES IN GENERAL
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- B60W50/00—Details of control systems for road vehicle drive control not related to the control of a particular sub-unit, e.g. process diagnostic or vehicle driver interfaces
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Abstract
The invention relates to the technical field of vehicle control, in particular to a hydraulic control method and a storage medium during follow-up braking. After receiving a braking deceleration command, the target braking pressure P is settargetCalculating; the hydraulic pressure regulating unit is based on the target brake pressure PtargetEstablishing a reference hydraulic pressure; when the reference hydraulic pressure reaches the target brake pressure PtargetThen, the hydraulic pressure adjusting unit performs first pressure-maintaining control; monitoring the vehicle speed and the longitudinal pose of the vehicle in real time, and when the vehicle speed is in a set vehicle speed range of v 1-v 2 and the longitudinal pose of the vehicle exceeds a calibrated pose threshold, performing pressure relief control; if the vehicle speed decreases to be not greater than the set vehicle speed threshold value v0, the second pressure holding control is performed. The dynamic vertical load of the front shaft and the rear shaft is promoted to be more uniform while the nod feeling is restrained, so that the brake hydraulic pressure is optimizedMeanwhile, the utilization rate of the adhesion coefficient between the road surface and the tire is improved, the service life of the ESC controller is prolonged, and the loss of the brake is reduced.
Description
Technical Field
The invention relates to the technical field of vehicle control, in particular to a hydraulic control method and a storage medium during follow-up braking.
Background
With the rapid progress of the internet technology, the intelligent degree of the automobile is higher and higher due to the continuous improvement of the requirements of people on the safety and the operability of the automobile. Full speed ACC start and stop functions have been applied in more and more vehicles. When the ACC follows the car, when the front car suddenly brakes and parks, the car also needs to be braked and parked. The main control system of the vehicle with the functions of full-speed ACC starting and stopping is divided into three parts: (1) detecting a target; (2) logic processing control; (3) and executing the action. The target detection is mainly to detect a target object in front of the vehicle through a millimeter wave radar, a camera or a fusion scheme of the millimeter wave radar and the camera. The processing control unit, namely the ADAS function controller, mainly analyzes and judges the self state of a controlled target object and a vehicle, and sends control instructions such as acceleration, deceleration, parking and the like according to a calibrated strategy. The action execution is in response to the command of the ADAS controller. The execution module is divided into two parts, one is a power control execution part, namely a VCU controller, and is responsible for acceleration; the other is a brake control execution part, i.e., an ESC module, which is responsible for deceleration braking and the like.
The logic of the existing brake control execution part is to directly enable the ESC to establish a hydraulic constant value of about 100bar when the ACC and the brake are required to be executed, so as to directly achieve a braking force capable of locking. This control logic does not take into account the actual driving conditions and the real-time braking torque requirements; because sudden braking can cause the vehicle to generate large pitching, particularly in the time period before the vehicle stops in the second half period of braking, a very obvious nodding feeling can occur, and drivers and passengers can feel strong discomfort. On the other hand, at a lower vehicle speed in the second half of braking, the braking system still gives a larger braking force, which damages the bearing capacity of the braking system.
Disclosure of Invention
The invention aims to provide a hydraulic control method and a storage medium for follow-up braking and stopping, aiming at the defects of the prior art, so that a reasonable braking hydraulic curve can be obtained, the braking pitching generated in the second half of braking is effectively inhibited, the vehicle has a better braking posture, and a driver and passengers have better comfortable experience.
The technical scheme of the invention is as follows: after receiving a braking deceleration command, the target braking pressure P is settargetCalculating;
the hydraulic pressure regulating unit is used for regulating the target brake pressure PtargetEstablishing a reference hydraulic pressure;
when the reference hydraulic pressure reaches the target brake pressure PtargetThen, the hydraulic pressure adjusting unit performs first pressure-maintaining control;
monitoring the vehicle speed and the longitudinal pose of the vehicle in real time, and when the vehicle speed is in a set vehicle speed range of v 1-v 2 and the longitudinal pose of the vehicle exceeds a calibrated pose threshold, performing pressure relief control;
if the vehicle speed decreases to be not greater than the set vehicle speed threshold value v0, the second pressure holding control is performed.
Preferably, the target brake pressure PtargetAnd obtaining the brake force of the front caliper-brake force-rear caliper-pipe pressure curve based on the pre-calibration.
Preferably, the target brake pressure PtargetThe calculation of (a) includes:
request value based on deceleration instruction
Calculating the total braking force F of the caliperxbtotal；
Obtaining the total braking force F meeting the calipers based on the curve of front caliper braking force-rear caliper braking force-pipe pressurexbtotalIn time, the pipeline hydraulic pressure P corresponding to the braking force of the front caliper and the braking force of the rear calipermax；
Hydraulic pressure P of pipelinemaxAs the target brake pressure Ptarget。
Preferably, the system also comprises a hydraulic pressure P for the pipelinemaxCorrecting the target brake pressure P to be the corrected line hydraulic pressuretargetTarget brake pressure Ptarget＝Pmax+ a, wherein a is a setting parameter.
Preferably, the longitudinal pose of the vehicle is judged through the pitch angle theta and the vertical bounce displacement z of the vehicle head.
Preferably, when the pitch angle theta is larger than the set pitch angle threshold value and the vehicle head vertical bounce displacement z is larger than the set vehicle head vertical bounce displacement threshold value, it is determined that the longitudinal pose of the vehicle exceeds the calibrated pose threshold value.
Preferably, the pressure relief control includes:
the liquid inlet valve is closed, and the liquid outlet valve is intermittently opened at the same time.
Preferably, the second holding pressure control includes:
and closing the liquid outlet valve LRAV, opening the liquid inlet valve LREV, driving the hydraulic pump to work by the direct current motor M, and closing the liquid inlet valve LREV until the pressure is increased to the set pressure.
Preferably, the liquid outlet valve is a linear switch valve and is controlled by pulses.
The invention has the beneficial effects that: when the following brake is stopped, the ESC hydraulic adjusting unit is used for carrying out three operations of pressurization, decompression and pressure maintaining to carry out coordination control. When the ESC responds to the deceleration command of the ACC, a larger brake hydraulic pressure is established at first, so that the deceleration of the first half stage is realized; when the vehicle speed is reduced to 20-30km/h, the braking hydraulic pressure is reduced downwards through longitudinal pose estimation of the vehicle and when the pose exceeds a calibration threshold value of the vehicle; at the moment, the main liquid inlet valve is closed, and the liquid outlet valve is intermittently opened to release pressure; and finally, when the vehicle speed is lower than 1km/h, establishing a pressure of about 15bar through the ESC hydraulic pressure regulating unit, and braking the vehicle at the original position. The hydraulic control of the scheme can promote the dynamic vertical load of the front shaft and the rear shaft to be more uniform while inhibiting the nod feeling, thereby improving the utilization rate of the adhesion coefficient between the road surface and the tire while optimizing the braking hydraulic pressure, prolonging the service life of the ESC controller and reducing the loss of the brake.
Drawings
FIG. 1 is a flow chart of a hydraulic control method for following braking of a vehicle according to the present invention;
FIG. 2 is a schematic of a front caliper brake force-rear caliper brake force-tube pressure curve of the present invention;
FIG. 3 is a schematic diagram of the hydraulic circuit of the ESC hydraulic pressure regulation unit of the present invention;
FIG. 4 is a schematic view of a hydraulic adjustment curve of the present invention;
FIG. 5 is a schematic diagram of the pulse control principle of the intermittent adjustment of the liquid outlet valve according to the present invention;
FIG. 6 is a schematic view of a vehicle attitude estimation model of the present invention;
fig. 7 is a schematic diagram of a brake control process applying the present invention.
Detailed Description
The invention will be further described in detail with reference to the following drawings and specific examples, which are not intended to limit the invention, but are for clear understanding.
As shown in fig. 1, the present invention provides a hydraulic control method for following braking, which includes:
s1: calculating a target brake pressure Ptarget. It includes:
s101: when ESC receives deceleration command, according to deceleration command request value
Calculating the total braking force F of the caliperxbtotal. The calculation method is as follows:
S102: combination formula
Obtaining the total braking force F meeting the calipers based on the curve of front caliper braking force-rear caliper braking force-pipe pressurexbtotalIn time, the pipeline hydraulic pressure P corresponding to the braking force of the front caliper and the braking force of the rear calipermaxI is 1 or 2, Fxb1Braking force of a front caliper;Fxb2the rear caliper braking force.
As shown in FIG. 2, in the front caliper brake force-rear caliper brake force-tube pressure curve, a unique front caliper brake force F can be obtained on the premise that the sum of the front caliper brake force and the rear caliper brake force is determinedxb1Braking force F of rear caliperxb2So that the curve yields the only line pressure, i.e. the line hydraulic pressure Pmax。
S103: based on pipeline hydraulic pressure PmaxCalculating a target brake pressure Ptarget. For safety reasons, hydraulic pressure P is required in the linemaxAdding the rest 10 bar; thus, the target brake pressure Ptarget＝Pmax+10bar。
Conventional target brake pressure PtargetThe required caliper braking force is reversely solved through deceleration, and then the solution is carried out through parameters such as the caliper structure, the friction coefficient and the like according to the caliper braking force. The tube pressure-braking force curve used in the scheme is obtained by directly testing through a bench, the influence of environmental factors, the temperature of the brake disc and the like on the friction coefficient is comprehensively considered, and the result is more accurate.
S2: according to the target brake pressure PtargetAnd performing hydraulic control. The hydraulic circuit of the ESC hydraulic pressure regulating unit is shown in fig. 3, wherein MC2 is a hydraulic master cylinder, HSR2 is a high pressure valve, USV2 is a reversing valve, LREV is a liquid inlet valve, LRAV is a liquid outlet valve, and LR and RF are caliper wheel cylinders, respectively. As shown in fig. 4, the hydraulic control flow mainly includes four stages:
s201: the hydraulic pressure regulating unit is based on the target brake pressure PtargetA reference hydraulic pressure is established. Taking an LR caliper wheel cylinder as an example, when active pressurization is carried out, the USV2 and the LRAV are closed; HSR2, LREV open; meanwhile, the direct current motor M drives the hydraulic pump to work, brake fluid is continuously pressed into the wheel cylinder, pressure rise is achieved, and the hydraulic pressure in the caliper at the moment is estimated by calculating the hydraulic pressure entering the wheel cylinder.
S202: when the target hydraulic pressure P is reachedtargetAnd then, the liquid inlet valve and the liquid outlet valve are closed to keep the pressure unchanged (namely, first pressure maintaining control), and finally, the powerful pressurization operation of the initial deceleration section is realized.
S203: the ACC controller continuously monitors the vehicle speed and the longitudinal pose of the vehicle, and when the vehicle speed is in a set vehicle speed range v 1-v 2 (20-30 km/h in the embodiment) and the longitudinal pose of the vehicle exceeds a calibrated pose threshold value, pressure relief control is performed. And when the pitch angle theta is larger than a set pitch angle threshold value and the vertical bounce displacement z of the locomotive is larger than a set vertical bounce displacement threshold value of the locomotive, judging that the longitudinal pose of the vehicle exceeds a calibrated pose threshold value.
The pressure relief control includes:
the HSR2, LREV valve is closed; the LRAV liquid outlet valve is intermittently opened and closed, so that the pressure of the wheel cylinder is orderly reduced; at this stage, as the vehicle speed is continuously reduced, the hydraulic pressure is reduced somewhat; at this stage, the longitudinal pitch of the vehicle is constantly optimized as the caliper brake force is reduced.
The operation of hydraulic pressure reduction can be realized through the intermittent adjustment of the LRAV liquid outlet valve; the LRAV liquid outlet valve is a linear switch valve, and the control mode is controlled by pulse; as shown in fig. 5, when the control pulse is 0, the liquid outlet valve is closed; when the control pulse is-1, the brake hydraulic pressure is somewhat reduced, so that the braking force at the wheel end of the vehicle is appropriately reduced, thereby adjusting the pitch angle.
S204: when the vehicle speed is reduced to 1km/h, the electromagnetic valves USV2 and LRAV are closed; HSR2, LREV open; and meanwhile, the direct current motor M drives the hydraulic pump to work, brake fluid is continuously pressed into the wheel cylinder, pressure rise is realized, when the pressure of the wheel cylinder reaches 15bar, pressure maintaining is carried out, and when pressure maintaining is carried out, the LREV liquid inlet valve is closed, the pressure is kept unchanged at 15bar, so that slipping caused by road surface gradient and other reasons is prevented, and the vehicle is safely stopped in situ.
Preferably, the estimation algorithm of the pitching attitude of the whole vehicle needs to construct an estimation model on the basis of a dynamic model of the whole vehicle; the input signals include vehicle speed, wheel speed and corresponding vehicle deceleration signal. The pitch attitude estimation algorithm needs calibration test in the design early stage of the function. The whole vehicle dynamic model mainly relates to chassis dynamic parameters of a vehicle, including tires, suspension, wheelbase, mass center, vehicle weight and the like of the vehicle. According to the information, a whole vehicle pitching attitude calculation model of the vehicle is established; the model CAN dynamically estimate the pitching state of the whole vehicle according to the input information on the CAN bus. The estimation algorithm is stored in the ACC controller, and a calibration test needs to be carried out on the algorithm in the vehicle development stage. Wherein the wheel speed, the vehicle speed and the deceleration of the whole vehicle are obtained by a wheel speed sensor arranged at 4 wheels, transmitted to a CAN bus through an ESC and then obtained by an ACC controller.
When the design parameters of the vehicle are determined, the dynamic body pitch is mainly determined by the initial speed and the dynamic deceleration of the vehicle. Based on the above situation, the scheme adopts the technical scheme that when the attitude estimation algorithm finds that the attitude change of the whole vehicle is large, namely the change of theta and z is large, the pitching moment M caused by the deceleration of the vehicle is influenced by properly adjusting the wheel cylinder pressure of the brakeyAnd finally, the purpose of inhibiting pitching changes is achieved. Wherein, theta-pitch angle; z-vertical bounce displacement of the locomotive. The calculation algorithm is integrated in an ACC controller of the vehicle, and the required parameters mainly comprise two parts: and (4) vehicle configuration parameters and dynamic variation.
Among the above parameters, the vehicle configuration parameters mainly refer to the wheel base, suspension damping, front and rear axle loads, etc. of the vehicle, and these parameters are integrated in the ADAS controller as known variables in the vehicle development stage. The dynamic variation mainly refers to the deceleration caused by braking and the variation force applied to the front and rear suspensions. And dynamic analysis can be performed according to the parameters, so that the real-time longitudinal pose change of the vehicle can be dynamically estimated.
Two monitoring parameters of the vehicle dynamic pitch, namely a theta-pitch angle; z-vertical bounce displacement of the locomotive, as shown in fig. 6, the estimation model is as follows:
Ffront，Frearis frontThe rear suspension is stressed; kf，KrFront and rear suspension stiffness; cf，CrFront and rear suspension damping; l isfont，LrontThe distance between the front shaft and the rear shaft is;
theta is a pitch angle; z is the vertical bounce displacement of the vehicle head; mfront，MrearFront and rear suspension moment;
Mfront＝-LfrontFfront
Mrear＝LrFrear
mbis the sprung mass of the car body; myA pitching moment caused for deceleration; i isyyIs the inertia of the vehicle body; g is a gravitational acceleration constant;
the second-order acceleration is the vertical bounce displacement of the locomotive;
is a pitch angle second order acceleration.
Through the estimation strategy, two parameters representing the longitudinal pose of the vehicle can be estimated: theta-pitch angle; z-vertical bounce displacement of the locomotive. And when the two are larger than the set threshold value, triggering the wheel cylinder hydraulic pressure adjusting strategy. Regarding the threshold setting of the pose parameters, the design method mainly carries out subjective dynamic calibration through a trained tester, and carries out subjective parameter calibration according to different calibration styles of different vehicle type projects. For a vehicle with a biased style of motion, it may be set higher; for a more comfortable vehicle, the setting can be adjusted in advance with a lower setting.
Preferably, the deceleration command is calculatedAnd calculating a safe time interval value according to the working condition of the vehicle for judgment. If the TTC is less than 0.8 second, the ACC controller is required to send a braking brake command. The method for calculating the safe time interval TTC corresponding to the hydraulic starting instruction comprises the following steps:
wherein D isrelIs the relative distance of two vehicles, VrelThe relative speed of the two vehicles. In addition, when the vehicle is required to stop, the safe distance d between the vehicle and the target vehicle0. Then the asphalt-based AEB control system should immediately generate a full brake command when the relative distance of the two cars reaches the critical distance Dbr. The Dbr calculation method comprises the following steps: dbr ═ TTC · Vrel+d0. When the ESC receives a deceleration command, the ESC realizes rapid pressurization by coordinating and controlling a valve, a pump and the like of the ESC. When the ESC responds to a braking and stopping command sent by the ACC controller, the ESC actuator calculates a commanded deceleration request value, and a brake hydraulic circuit is pressurized by a hydraulic pump of the ESC.
Preferably, the design structure of the ACC function is mainly divided into four parts, namely a front vehicle detection module, an ACC controller unit, a VCU acceleration control unit and an ESC brake execution unit. As shown in fig. 7, the detection module with the ACC function detects a front target vehicle in real time, obtains the relative distance and the relative speed between the two vehicles, and obtains the real degree of the front vehicle by calculation; and then the detected information is input into an ACC controller unit, and the controller unit performs comprehensive judgment by combining basic information such as self vehicle speed, gear and the like acquired from a CAN bus and a TTC-collision time-distance algorithm and sends out a corresponding instruction (acceleration/braking). If the command is an acceleration command, the VCU controller of the whole vehicle responds; if a braking command is issued, a response is made by the ESC controller. And after receiving the deceleration information, the ESC controller establishes a reference hydraulic pressure according to the received reference deceleration value. The pitching attitude of the whole vehicle is estimated while the reference hydraulic pressure is established, and then the hydraulic pressure is dynamically adjusted through the attitude adjustment algorithm designed by the patent, so that the pitching attitude is controlled.
Details not described in this specification are within the skill of the art that are well known to those skilled in the art. The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The present invention is not limited to the above embodiments, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included in the scope of the claims of the present invention which are filed as the application.
Claims (10)
1. A hydraulic control method for follow-up braking and stopping is characterized in that:
receiving brakeAfter the vehicle is decelerated, the target brake pressure P is settargetCalculating;
the hydraulic pressure regulating unit is used for regulating the target brake pressure PtargetEstablishing a reference hydraulic pressure;
when the reference hydraulic pressure reaches the target brake pressure PtargetThen, the hydraulic pressure adjusting unit performs first pressure-maintaining control;
monitoring the vehicle speed and the longitudinal pose of the vehicle in real time, and when the vehicle speed is in a set vehicle speed range of v 1-v 2 and the longitudinal pose of the vehicle exceeds a calibrated pose threshold, performing pressure relief control;
if the vehicle speed decreases to be not greater than the set vehicle speed threshold value v0, the second pressure holding control is performed.
2. The hydraulic control method for the follow brake according to claim 1, wherein: the target brake pressure PtargetAnd obtaining the brake force of the front caliper-brake force-rear caliper-pipe pressure curve based on the pre-calibration.
3. The hydraulic control method for the follow brake according to claim 2, wherein: the target brake pressure PtargetThe calculation of (a) includes:
request value based on deceleration instruction
Calculating the total braking force F of the caliperxbtotal；
Obtaining the total braking force F meeting the calipers based on the curve of front caliper braking force-rear caliper braking force-pipe pressurexbtotalIn time, the pipeline hydraulic pressure P corresponding to the braking force of the front caliper and the braking force of the rear calipermax；
Hydraulic pressure P of pipelinemaxAs the target brake pressure Ptarget。
4. The hydraulic control method for the follow brake according to claim 3, wherein: also comprises a pair of pipeline hydraulic pressure PmaxCorrecting the pipeline hydraulic pressure after correction to be used as a targetNominal brake pressure PtargetTarget brake pressure Ptarget＝Pmax+ a, wherein a is a setting parameter.
5. The hydraulic control method for the follow brake according to claim 1, wherein: and the longitudinal pose of the vehicle is judged through the pitch angle theta and the vertical bounce displacement z of the vehicle head.
6. The hydraulic control method for the follow brake according to claim 5, wherein: and when the pitch angle theta is larger than a set pitch angle threshold value and the vertical bounce displacement z of the vehicle head is larger than a set vertical bounce displacement threshold value of the vehicle head, judging that the longitudinal pose of the vehicle exceeds a calibrated pose threshold value.
7. The hydraulic control method for the follow brake according to claim 1, wherein: the pressure relief control includes:
the liquid inlet valve is closed, and the liquid outlet valve is intermittently opened at the same time.
8. The hydraulic control method for the follow brake according to claim 1, wherein: the second holding pressure control includes:
and closing the liquid outlet valve LRAV, opening the liquid inlet valve LREV, driving the hydraulic pump to work by the direct current motor M, and closing the liquid inlet valve LREV until the pressure is increased to the set pressure.
9. The hydraulic control method for the follow brake according to claim 1, wherein: the liquid outlet valve is a linear switch valve and is controlled by pulses.
10. A computer-readable storage medium storing a computer program, characterized in that: the computer program when executed by a processor implementing the steps of the method according to any one of claims 1 to 9.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4852950A (en) * | 1987-09-16 | 1989-08-01 | Toyota Jidosha Kabushiki Kaisha | Vehicle braking system capable of preventing rock-back motion of driver/passenger upon vehicle stopping |
| JPH06107244A (en) * | 1992-09-30 | 1994-04-19 | Isuzu Motors Ltd | Posture controller of cab |
| CN102616101A (en) * | 2011-01-28 | 2012-08-01 | 日产自动车株式会社 | Vehicle running state control device and vehicle running state control method |
| CN102673545A (en) * | 2011-03-16 | 2012-09-19 | 富士重工业株式会社 | Vehicle driving support apparatus |
| CN102933421A (en) * | 2010-06-11 | 2013-02-13 | 日立建机株式会社 | Pitching control device for electric vehicle |
| CN103171537A (en) * | 2011-12-22 | 2013-06-26 | 日信工业株式会社 | Braking hydraulic control device used for vehicle |
| CN103879392A (en) * | 2012-12-21 | 2014-06-25 | 日信工业株式会社 | Vehicular brake hydraulic pressure control apparatus |
| CN107168397A (en) * | 2017-04-22 | 2017-09-15 | 三明学院 | Automobile four-wheel system independent parallel vibration control method |
| CN108501910A (en) * | 2018-03-09 | 2018-09-07 | 同济大学 | A kind of vehicle master cylinder constant frequency pressure regulating formula braking anti-lock method |
-
2020
- 2020-10-26 CN CN202011159748.8A patent/CN112141079A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4852950A (en) * | 1987-09-16 | 1989-08-01 | Toyota Jidosha Kabushiki Kaisha | Vehicle braking system capable of preventing rock-back motion of driver/passenger upon vehicle stopping |
| JPH06107244A (en) * | 1992-09-30 | 1994-04-19 | Isuzu Motors Ltd | Posture controller of cab |
| CN102933421A (en) * | 2010-06-11 | 2013-02-13 | 日立建机株式会社 | Pitching control device for electric vehicle |
| CN102616101A (en) * | 2011-01-28 | 2012-08-01 | 日产自动车株式会社 | Vehicle running state control device and vehicle running state control method |
| CN102673545A (en) * | 2011-03-16 | 2012-09-19 | 富士重工业株式会社 | Vehicle driving support apparatus |
| CN103171537A (en) * | 2011-12-22 | 2013-06-26 | 日信工业株式会社 | Braking hydraulic control device used for vehicle |
| CN103879392A (en) * | 2012-12-21 | 2014-06-25 | 日信工业株式会社 | Vehicular brake hydraulic pressure control apparatus |
| CN107168397A (en) * | 2017-04-22 | 2017-09-15 | 三明学院 | Automobile four-wheel system independent parallel vibration control method |
| CN108501910A (en) * | 2018-03-09 | 2018-09-07 | 同济大学 | A kind of vehicle master cylinder constant frequency pressure regulating formula braking anti-lock method |
Non-Patent Citations (1)
| Title |
|---|
| 黄源: "线控制动***制动力分配策略研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
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Application publication date: 20201229 |