1. A vehicle slope starting method based on an electronic parking system is characterized by comprising the following steps:

s1, signal collection

Acquiring a vehicle ignition state signal, an EPB state signal, a vehicle speed signal, a gradient value signal, a gear signal, a clutch opening signal, an accelerator opening signal, an image shaking amplitude of a vehicle camera and a vibration signal of a vehicle;

s2, condition judgment

And if the 9 signals all meet the preset condition, the EPB automatically releases the parking.

2. The vehicle hill start method based on the electronic parking system as claimed in claim 1, wherein 9 signals of the vehicle within a preset time are acquired.

3. The electronic parking system-based vehicle hill start method as claimed in claim 2, wherein the preset time is 100 ms.

4. The vehicle hill start method based on the electronic parking system as claimed in claim 1, wherein the preset conditions are specifically: the ignition state of the vehicle is ignition, the EPB state is parking, the vehicle speed is 0-5km/h, the gradient value is 0-30 degrees, the gear is a forward gear, the opening degree of a clutch is more than 5 percent, the opening degree of an accelerator is more than 3 percent, and the image shaking amplitude of a vehicle camera and the vibration signal of the vehicle are the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the vehicle is in a half-clutch point.

5. The vehicle hill start method based on the electronic parking system as claimed in claim 4, wherein the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point are calibrated according to the grade value and the gear to obtain the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point.

6. The vehicle hill start method based on the electronic parking system as claimed in claim 4, wherein when starting the vehicle with the manual transmission, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the engine speed is in the interval of 2000-3000rpm are calibrated, the clutch opening signal of the clutch is matched, and the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the vehicle is at the half-clutch point are accurately calibrated.

7. The vehicle hill start method based on the electronic parking system as claimed in claim 4, wherein the forward gear is 1 st gear or 2 nd gear.

8. The vehicle hill start method based on the electronic parking system as claimed in claim 1, wherein the vibration signal of the vehicle is a vibration signal of an engine of the vehicle or a position near the engine.

9. The vehicle hill start method based on the electronic parking system as claimed in claim 1, wherein a vehicle meter displays the state of the EPB in real time.

10. An electronic parking system based vehicle hill start system for implementing the electronic parking system based vehicle hill start method as claimed in any one of claims 1 to 9, characterized by comprising:

EMS, used for obtaining the vehicle ignition state signal;

the EPB is used for acquiring an EPB state signal;

ESC, is used for obtaining the speed signal of the vehicle;

the gradient sensor is used for acquiring a gradient value signal;

the TCU is used for acquiring gear signals;

the clutch stroke sensor is used for acquiring a clutch opening signal;

the accelerator travel sensor is used for acquiring an accelerator opening signal;

the camera is used for acquiring the image shaking amplitude of the vehicle camera;

the vibration sensor is used for acquiring a vibration signal of the vehicle;

and the processor is used for judging whether the acquired 9 signals all meet preset conditions.

Background

Modern automobiles seek to improve the comfort of drivers more and more on the premise of meeting safety, the control of related functions of the automobiles is simpler and simpler, a plurality of functions can be completed even by automatic control of the automobiles, the frequent operation of drivers is reduced, and the fatigue degree of the drivers is reduced.

Electronic parking brake system, namely: electric parkingbrake, abbreviated EPB in english. EPB controls parking brake and parking release through CAN network line, has replaced traditional mechanical pull rod manual brake in the function. The electronic hand brake can be automatically released for parking by sensing the operation of a driver during vehicle starting without manually turning off the electronic hand brake during vehicle starting.

However, the existing EPB has many defects in function and has certain potential safety hazard. For example, when an MT (Manual Transmission) vehicle starts, the EPB automatically releases the parking function after releasing the clutch pedal and stepping on the accelerator because the conventional EPB mainly determines the accelerator signal value and the clutch signal value, and automatically releases the parking when both the accelerator signal value and the clutch signal value reach a certain value.

Because the deviation ratio of the signal value of the clutch at the half-clutch point is large, particularly under the condition of a slope, the phenomena of vehicle slipping caused by early EPB release and flameout caused by late EPB release are easily caused, the driver is extremely uncomfortable if the vehicle is light, and certain danger is caused if the vehicle is heavy. Therefore, how to avoid the premature and late release of the parking, and improve the driving safety and comfort, is the focus of the EPB system development.

Disclosure of Invention

The invention aims to provide a vehicle slope starting method and system based on an electronic parking system, which improve the comfort and safety of automatic EPB release of an MT vehicle and enable the EPB automatic release function to better realize the slope starting assistance function.

The technical scheme provided by the invention is as follows:

a vehicle slope starting method based on an electronic parking system comprises the following steps:

s1, signal collection

Acquiring a vehicle ignition state signal, an EPB state signal, a vehicle speed signal, a gradient value signal, a gear signal, a clutch opening signal, an accelerator opening signal, an image shaking amplitude of a vehicle camera and a vibration signal of a vehicle;

s2, condition judgment

And if the 9 signals all meet the preset condition, the EPB automatically releases the parking.

Preferably, 9 signals of the vehicle within a preset time are acquired.

Preferably, the preset time is 100 ms.

Preferably, the preset conditions are specifically: the ignition state of the vehicle is ignition, the EPB state is parking, the vehicle speed is 0-5km/h, the gradient value is 0-30 degrees, the gear is a forward gear, the opening degree of a clutch is more than 5 percent, the opening degree of an accelerator is more than 3 percent, and the image shaking amplitude of a vehicle camera and the vibration signal of the vehicle are the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the vehicle is in a half-clutch point.

Preferably, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point position of the vehicle are calibrated according to the gradient value and the gear, and the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point are obtained.

Preferably, when the manual-gear vehicle starts, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the engine speed is within the range of 2000-3000rpm are calibrated, the clutch opening signal of the clutch is matched, and the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the vehicle is at a half-clutch point are accurately calibrated.

Preferably, the forward gear is 1 gear or 2 gears

Preferably, the vibration signal of the vehicle is a vibration signal of the engine of the vehicle or a position near the engine.

Preferably, the vehicle meter displays the status of the EPB in real time.

A vehicle hill starting system based on an electronic parking system for realizing the vehicle hill starting method based on the electronic parking system comprises the following steps:

EMS, used for obtaining the vehicle ignition state signal;

the EPB is used for acquiring an EPB state signal;

ESC, is used for obtaining the speed signal of the vehicle;

the gradient sensor is used for acquiring a gradient value signal;

the TCU is used for acquiring gear signals;

the clutch stroke sensor is used for acquiring a clutch opening signal;

the accelerator travel sensor is used for acquiring an accelerator opening signal;

the camera is used for acquiring the image shaking amplitude of the vehicle camera;

the vibration sensor is used for acquiring a vibration signal of the vehicle;

and the processor is used for judging whether the acquired 9 signals all meet preset conditions.

The invention has the beneficial effects that:

according to the invention, the vehicle ignition state signal, the EPB state signal, the vehicle speed signal, the gradient value signal, the gear position signal, the clutch opening signal, the accelerator opening signal, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle are obtained, and whether the 9 signals meet the preset conditions or not is judged, so that whether the EPB needs to be automatically released for parking is judged, and therefore, the EPB automatic release function of the MT vehicle is safer and more comfortable, and the EPB automatic release function can better realize the slope auxiliary function.

Drawings

FIG. 1 is a schematic diagram of a vehicle hill start system based on an electronic parking system.

FIG. 2 is a flowchart of a method for acquiring image shake amplitude by a camera according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described with reference to the accompanying drawings and specific embodiments, but the scope of the present invention is not limited to the following embodiments.

The conventional manual transmission vehicle is parked and parked on a slope, and when the vehicle is driven again to start on the slope, the automatic release function of the EPB is used, so that the following phenomena can occur:

1) when a driver steps on a clutch pedal, the clutch pedal is engaged; and in the process of slowly lifting the clutch pedal and stepping down the accelerator pedal, the EPB is released in advance, so that the vehicle slips down on a slope, and the vehicle is dangerous.

2) When a driver steps on a clutch pedal, the clutch pedal is engaged; and in the process of slowly lifting the clutch pedal and stepping down the accelerator pedal, the EPB is released too late, so that the vehicle is unsmooth in starting and is subjected to jerking. In more serious cases, the EPB is not released, resulting in the vehicle stalling and failure to drive normally.

In order to solve the problems, the invention provides a vehicle slope starting method based on an electronic parking system, which comprises the following steps:

s1, signal collection

As shown in table 1, a vehicle ignition state signal, an EPB state signal, a vehicle speed signal, a gradient value signal, a shift position signal, a clutch opening signal, an accelerator opening signal, an image shake amplitude of a vehicle camera, and a vibration signal of a vehicle are acquired. Of these 9 signals, there are periodic signals and also event signals. And taking signal values of 9 signals within 100ms time, and carrying out signal transmission by using a vehicle CAN bus.

TABLE 1 Signal acquisition Table

S2, condition judgment

And if the 9 signals all meet the preset condition, the EPB automatically releases the parking. As shown in table 2, the preset conditions are specifically: the ignition state of the vehicle is ignition, the EPB state is parking, the vehicle speed is 0-5km/h, the gradient value is 0-30 degrees, the gear is a forward gear, the opening degree of a clutch is more than 5 percent, the opening degree of an accelerator is more than 3 percent, and the image shaking amplitude of a vehicle camera and the vibration signal of the vehicle are the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle when the vehicle is in a half-clutch point.

TABLE 2 Release parking determination Condition

Serial number	Vehicle condition demand	Signal	Signal value
				1	Vehicle ignition	Vehicle ignition status	1: ignition
2	The vehicle is stationary	Vehicle speed signal	0-5km/h
				3	Vehicle position	Slope value signal	0°～30°
4	Stepping on the gas	Throttle opening signal	＞3％
				5	After stepping on the clutch and lifting	Clutch opening signal	＞5％
6	Forward gear	Gear signal	2: forward gears 1-6
				7		Camera signals	1: vehicle launch
8		Vibration sensor signal	1: vehicle launch
				9	EPB in park state	EPB status signal	0: parking device

The logic judgment is carried out, the state of the CAN bus signal value is reflected according to the control of a driver on the vehicle, the logic operation result is output to an execution mechanism through EPB controller logic operation in combination with the vehicle state, and the automatic release of the vehicle CAN be better realized.

In the embodiment, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point position of the vehicle are calibrated according to the gradient value and the gear, so that the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle at the half-clutch point are obtained. Wherein the semi-clutch point of the vehicle clutch is judged: firstly, calibrating amplitude and vibration frequency data of a vehicle when a vehicle clutch is at a half-clutch point position to obtain credible amplitude and vibration frequency data; and then the vehicle state is judged reversely through the amplitude and the vibration frequency data, namely whether the vehicle is in a starting state or not is judged. If the amplitude and the vibration frequency data meet the vehicle starting state, the accurate state of the vehicle at the moment can be finally confirmed by referring to the clutch signal value, the accelerator signal value and the gear state signal.

In another feasible scheme, as shown in table 3, when the manual transmission vehicle starts, the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle are calibrated when the engine speed is within the range of 2000-3000rpm, the clutch opening signal of the clutch is matched, and the image shaking amplitude of the vehicle camera and the vibration signal of the vehicle are accurately calibrated when the vehicle is at a half-clutch point.

TABLE 3 semi-Clutch Point acquisition mode

A vehicle hill starting system based on an electronic parking system for realizing the vehicle hill starting method based on the electronic parking system comprises the following steps:

the EMS, namely, the Engine Management System, is used for acquiring a vehicle ignition state signal.

And the EPB is used for acquiring an EPB state signal.

The ESC, Electronic Stability Controller, is used for obtaining a vehicle speed signal.

And the gradient sensor is used for acquiring a gradient value signal.

The TCU, namely the Transmission Control Unit, is used for acquiring a gear signal.

And the clutch stroke sensor is used for acquiring a clutch opening degree signal.

And the accelerator travel sensor is used for acquiring an accelerator opening signal.

The camera is used for acquiring the image shaking amplitude of the vehicle camera; the object can be identified by using a forward-looking camera used by the existing ADAS function, as shown in fig. 2, by selecting a characteristic object, performing image processing on the characteristic object, and comparing the positions of the same characteristic object in unit time, the amplitude and the vibration frequency of the vehicle are extracted and used for judging the shaking condition of the vehicle.

And the vibration sensor is used for acquiring a vibration signal of the vehicle. Optionally, the vibration signal of the vehicle is a vibration signal of the engine of the vehicle or a position near the engine.

And the processor is used for judging whether the acquired 9 signals all meet preset conditions. The processor may be selected from an ECU (electronic Control Unit) electronic controller unit.

In addition, the vehicle instrument displays the state of the EPB in real time, so that a driver can know the current vehicle condition conveniently.

It will be understood by those skilled in the art that the foregoing is merely a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included within the scope of the present invention.