WO2018227933A1

WO2018227933A1 - Vehicle control method and system

Info

Publication number: WO2018227933A1
Application number: PCT/CN2017/118833
Authority: WO
Inventors: 刘成祺; 谢明维; 李从心; 易迪华
Original assignee: 北京新能源汽车股份有限公司
Priority date: 2017-06-14
Filing date: 2017-12-27
Publication date: 2018-12-20
Also published as: CN107264523B; CN107264523A

Abstract

A vehicle control method and system, the method comprising: acquiring a maximum deceleration which a road surface that a current vehicle is on is capable of providing; acquiring first data, comprising a relative speed and/or time interval between a target vehicle and the current vehicle; the target vehicle being a vehicle in front of the current vehicle which is closest to the current vehicle; according to the first data, determining whether the target vehicle is in a braking state; when the target vehicle is in a braking state, acquiring a target deceleration required by the current vehicle; according to the maximum deceleration and the target deceleration, deciding whether there is a rear-ending risk for the current vehicle; when there is a rear-ending risk, controlling the current vehicle to brake and turn so as to decelerate at the maximum deceleration. The present method uses a maximum deceleration a road surface a current vehicle is on can provide and a required target deceleration as a basis for determining whether there is a rear-ending risk, solving the problem in current ACC control processes of not considering road surface adhesion conditions, leading to poor control results and low safety.

Description

Vehicle control method and system

Cross-reference to related applications

This application claims the priority of the Chinese Patent Application No. "201710446105.3" filed on June 14, 2017 by Beijing New Energy Automobile Co., Ltd., entitled "Vehicle Control Method and System".

Technical field

The present invention relates to the field of vehicle engineering, and in particular, to a vehicle control method and system.

Background technique

At present, compared with traditional cars, pure electric vehicles reduce emissions and reduce water pollution caused by oil leakage. Therefore, pure electric vehicles are increasingly favored by consumers.

The Adaptive Cruise Control (ACC) controls the safe driving of the vehicle, which can effectively alleviate the driver's driving fatigue and ensure the safe driving of the vehicle. During the running of the vehicle, when the distance from the preceding vehicle is too small, the ACC can coordinate the action with the anti-lock braking system and the engine control system to properly brake the wheel and reduce the output power of the engine. The vehicle is always at a safe distance from the vehicle in front. At present, adaptive cruise systems are widely used in traditional fuel vehicles, but are rarely used in pure electric vehicles.

ACC's control ability is often affected by road surface adhesion conditions. Especially in the low road conditions such as sand, mud, snow, etc., when the current vehicle is performing emergency braking, due to the limited adhesion that the road can provide, under the activation condition of the ACC, the current braking force of the vehicle may be insufficient. This poses a risk of rear-end collisions, which reduces the control effect and thus the safety of the car.

Summary of the invention

The present invention aims to solve at least one of the technical problems in the related art to some extent.

Accordingly, a first object of the present invention is to provide a vehicle control method for determining whether a vehicle has a rear-end collision risk based on a maximum deceleration that can be provided by a road on which the vehicle is located and a target deceleration required by the vehicle. In the existing vehicle control method, the road surface adhesion condition is not considered, resulting in poor control effect and low safety of the vehicle.

A second object of the present invention is to propose a vehicle control system.

A third object of the present invention is to provide a vehicle control device.

A fourth object of the present invention is to provide a computer program product.

A fifth object of the present invention is to provide a non-transitory computer readable storage medium.

In order to achieve the above object, a first aspect of the present invention provides a vehicle control method including: acquiring a maximum deceleration that can be provided by a road surface on which a current vehicle is located; and acquiring a relative speed between the target vehicle and the current vehicle and/or Or first time data of the time interval; wherein the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle; determining whether the target vehicle is in a braking state according to the first data; acquiring the current when the target vehicle is in a braking state The target deceleration required by the vehicle; according to the maximum deceleration and the target deceleration, it is judged whether there is a risk of rear-end collision in the current vehicle; when there is a risk of rear-end collision, the current vehicle is controlled to decelerate and decelerate at the maximum deceleration.

The vehicle control method according to the embodiment of the present invention, according to the maximum deceleration that can be provided by the road surface on which the current vehicle is located, and the first data including the relative speed and/or the time interval between the target vehicle and the current vehicle, according to the first data Determining whether the target vehicle is in a braking state, obtaining a target deceleration required by the current vehicle when the target vehicle is in a braking state, and determining whether the current vehicle has a rear-end risk according to the maximum deceleration and the target deceleration, when there is a rear-end risk At this time, the current vehicle is controlled to decelerate braking and steering at the maximum deceleration. In the present embodiment, the function of determining whether the vehicle has a rear-end risk according to the road surface attachment condition is added to the original function of the ACC. When the current vehicle is in the braking state, the maximum deceleration that can be provided on the road where the current vehicle is located and the target deceleration required by the current vehicle are used as a basis for judging whether there is a risk of rear-end collision, and the existing ACC control process is solved. The problem of poor adhesion and low safety is not considered in the road surface adhesion conditions, which improves the control effect and safety of the vehicle.

In addition, the vehicle control method of the embodiment of the present invention further has the following additional technical features:

In an embodiment of the present invention, obtaining the maximum deceleration that the current vehicle is on the road surface includes: acquiring a road surface adhesion coefficient of the current vehicle road surface; and obtaining a maximum deceleration according to the road surface adhesion coefficient.

In an embodiment of the present invention, acquiring the road surface adhesion coefficient of the current vehicle road surface includes: acquiring wheel speed information of the driving wheel and the driven wheel of the current vehicle; calculating vehicle speed information of the current vehicle according to the wheel speed information; and according to the wheel speed information and The vehicle speed information is calculated, and the slip ratio of the driving wheel is calculated; the road surface adhesion coefficient is determined according to the centroid acceleration of the current vehicle and the slip ratio of the driving wheel.

In an embodiment of the present invention, the obtaining the maximum deceleration according to the road surface adhesion coefficient comprises: acquiring the slope information of the road surface and the weight of the current vehicle; and obtaining the vertical distance of the current vehicle relative to the road surface according to the slope information and the weight. Force; according to the vertical component and the road adhesion coefficient, the maximum deceleration is obtained.

In an embodiment of the present invention, determining whether the current vehicle has a rear-end collision risk according to the maximum deceleration and the target deceleration comprises: comparing the target deceleration with the maximum deceleration; and if the target deceleration is greater than the maximum deceleration, determining There is a risk of rear-end collision.

In an embodiment of the present invention, determining whether the target vehicle is in a braking state according to the first data comprises: comparing a relative speed with a relative speed of a previous moment; and determining a target when the relative speed is less than a relative speed of a previous moment The vehicle is in a braking state; or, the first time interval is compared with a second time interval of the previous time; if the first time interval is less than the second time interval, it is determined that the target vehicle is in a braking state.

In an embodiment of the present invention, the road surface adhesion coefficient is continuously detected; whether the detected danger level corresponding to the road surface adhesion coefficient is decreased; if the danger level is decreased, the target vehicle is reselected in the lane to follow.

In an embodiment of the present invention, in the process of controlling the current vehicle steering, the image information in the target lane to be turned is acquired in real time; and whether the side vehicle exists in the target lane is determined according to the image information; wherein the side vehicle is The vehicle with the distance between the current vehicle being lower than the preset threshold; if there is a side vehicle in the image information, controlling the current vehicle to issue the alarm information.

In order to achieve the above object, a second aspect of the present invention provides a vehicle control system including: an ACU for acquiring a maximum deceleration that can be provided by a road on which a current vehicle is located; and a data collection device for acquiring a target vehicle. First data relating to relative speed and/or time interval between the current vehicle; wherein the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle; ACC for determining whether the target vehicle is in accordance with the first data The moving state, when the target vehicle is in the braking state, acquires the target deceleration required by the current vehicle, and determines whether there is a rear-end risk in the current vehicle according to the maximum deceleration and the target deceleration, and controls when there is a risk of rear-end collision. The ESP of the current vehicle decelerates the brake at the maximum deceleration and controls the EPS steering of the current vehicle; the ESP is used to control the current vehicle to decelerate the brake at the maximum deceleration according to the command of the ACC; the EPS is used to control the steering according to the command of the ACC. The organization is turning.

The vehicle control system of the embodiment of the present invention acquires the maximum deceleration that the current vehicle is on the road surface through the ACU, and acquires the first data including the relative speed and/or the time interval between the target vehicle and the current vehicle through the data collection device. The ACC determines whether the target vehicle is in a braking state according to the first data, acquires a target deceleration required by the current vehicle when the target vehicle is in a braking state, and determines whether the current vehicle has a rear-end collision according to the maximum deceleration and the target deceleration. Risk, when there is a rear-end risk, the current vehicle's ESP is controlled to decelerate at maximum deceleration and control the current vehicle's EPS for steering. In the present embodiment, the function of determining whether the vehicle has a rear-end risk according to the road surface attachment condition is added to the original function of the ACC. When the current vehicle is in the braking state, the maximum deceleration that can be provided on the road where the current vehicle is located and the target deceleration required by the current vehicle are used as a basis for judging whether there is a risk of rear-end collision, and the existing ACC control process is solved. The problem of poor adhesion and low safety is not considered in the road surface adhesion conditions, which improves the control effect and safety of the vehicle.

In addition, the vehicle control system of the embodiment of the present invention further has the following additional technical features:

In an embodiment of the present invention, the ACU is specifically configured to acquire a road surface adhesion coefficient of a road surface on which the current vehicle is located, and obtain a maximum deceleration rate according to the road surface adhesion coefficient.

In an embodiment of the present invention, the ESP is specifically configured to acquire wheel speed information of the driving wheel and the driven wheel of the current vehicle, calculate the vehicle speed information of the current vehicle according to the wheel speed information, and send the wheel speed information and the vehicle speed information to the ACU. The ACU is specifically configured to calculate the slip ratio of the driving wheel according to the wheel speed information and the vehicle speed information, and determine the road surface adhesion coefficient according to the centroid acceleration of the current vehicle and the slip ratio of the driving wheel.

In an embodiment of the present invention, the ACU is specifically configured to acquire the slope information of the road surface and the weight of the current vehicle, and obtain the vertical component of the current vehicle relative to the road surface according to the slope information and the weight, according to the vertical component. And the road surface adhesion coefficient, the maximum deceleration is obtained.

In one embodiment of the present invention, the ACC is specifically used to compare the target deceleration with the maximum deceleration, and if the target deceleration is greater than the maximum deceleration, it is determined that there is a rear-end risk.

In an embodiment of the present invention, the ACC, specifically comparing the relative speed with the relative speed of the previous moment, determines that the target vehicle is in the braking state when the relative speed is less than the relative speed of the previous moment; or, the first time Comparing with the second time interval from the previous moment, if the first time interval is less than the second time interval, it is determined that the target vehicle is in the braking state.

In an embodiment of the present invention, the ACU is further configured to continuously detect the road surface adhesion coefficient; the ACC is further configured to determine whether the detected danger level corresponding to the road surface adhesion coefficient is decreased, and if the danger level decreases, Re-select the target vehicle in the lane for follow-up.

In an embodiment of the present invention, the ACC is further configured to acquire image information in a target lane to be turned in real time during the process of controlling the current vehicle steering, and determine whether there is a side vehicle in the target lane according to the image information; The side vehicle is a vehicle whose distance from the current vehicle is lower than a preset threshold, and if there is a side vehicle in the image information, the alarm information is sent through the BCM and/or ICM on the current vehicle.

In order to achieve the above object, a third aspect of the present invention provides a vehicle control apparatus including a memory and a processor, wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory. a program for performing the vehicle control method of the first aspect embodiment.

To achieve the above object, a fourth aspect of the present invention provides a computer program product for performing the vehicle control method of the first aspect when instructions in the computer program product are executed by the processor.

In order to achieve the above object, a fifth aspect of the present invention provides a non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program is executed by a processor to implement the first aspect of the embodiment. The vehicle control method described.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the embodiments will be briefly described below. It is obvious that the drawings in the following description are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work.

1 is a schematic structural diagram of a vehicle control system according to an embodiment of the present invention;

2 is a schematic structural diagram of another vehicle control system according to an embodiment of the present invention;

3 is a schematic flowchart of a vehicle control method according to an embodiment of the present invention;

FIG. 4 is a schematic flowchart diagram of another vehicle control method according to an embodiment of the present invention.

detailed description

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

A vehicle control method and system according to an embodiment of the present invention will be described below with reference to the drawings.

The control capability of the ACC on the vehicle is often affected by road surface attachment conditions. For example, in low-altitude road conditions such as sand, mud, snow, etc., when the current vehicle is performing emergency braking, due to the limited adhesion that the road surface can provide, even under the control of the ACC, the current vehicle brakes may be insufficient. As a result, the risk of rear-end collision is caused, which reduces the control effect and thus reduces the safety of the car.

In view of the above problems, the embodiment of the present invention adds ACC to a pure electric vehicle, and adds a function of judging whether the vehicle has a rear-end risk according to the road surface attachment condition in the original function of the ACC, and proposes a vehicle control system to realize the basis. The maximum deceleration provided by the road on which the vehicle is located and the target deceleration required by the vehicle determine whether the vehicle has a risk of rear-end collision. It is used to solve the problem that the existing vehicle control system does not consider the road surface attachment condition, resulting in poor control effect and safety of the vehicle. Low sexual problem.

FIG. 1 is a schematic structural diagram of a vehicle control system according to an embodiment of the present invention.

As shown in FIG. 1 , the vehicle control system includes: an Adhesion Coefficient Control Unit (ACU) 110, a data acquisition device 120, an ACC 130, and an Electronic Stability Program (ESP) 140. , Electric Power Steering (EPS) 150.

The ACU 110 is used to obtain the maximum deceleration that the current vehicle is on.

During the current vehicle in the driving mode, the ACU 110 can acquire the wheel speed information of the wheel through the wheel speed sensor disposed on the wheel, and the vehicle speed information can be calculated based on the wheel speed information. Further, the ACU 110 can obtain the maximum deceleration that the current vehicle is on, based on the wheel speed information, the vehicle speed information, and the centroid acceleration of the current vehicle collected by the acceleration sensor.

The data collection device 120 is configured to acquire first data including a relative speed and/or a time interval between the target vehicle and the current vehicle. Wherein, the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle; the time interval refers to a queue of vehicles traveling in the same lane, and the current vehicle can catch up with the target vehicle in the case that the current vehicle is traveling at the current speed. Time required.

The ACC 130 is configured to determine, according to the first data, whether the target vehicle is in a braking state, acquire a target deceleration required by the current vehicle when the target vehicle is in a braking state, and determine whether the current vehicle is based on the maximum deceleration and the target deceleration. There is a risk of rear-end collision, and when it is determined that there is a risk of rear-end collision, the ESP 140 controlling the current vehicle is decelerated to brake and steered at the maximum deceleration.

The ESP 140 is used to control the current vehicle to decelerate the brake at maximum deceleration and control the EPS 150 for steering according to the instructions of the ACC 130.

The EPS 150 controls the steering of the current vehicle steering according to the instructions of the ACC 130.

The vehicle control system of the embodiment of the present invention acquires the maximum deceleration that the current vehicle is on the road surface through the ACU, and acquires the first data including the relative speed and/or the time interval between the target vehicle and the current vehicle through the data collection device. The ACC determines whether the target vehicle is in a braking state according to the first data, acquires a target deceleration required by the current vehicle when the target vehicle is in a braking state, and determines whether the current vehicle has a rear-end collision according to the maximum deceleration and the target deceleration. Risk, when there is a risk of rear-end collision, control the ESP of the current vehicle to decelerate the brake with maximum deceleration and control the EPS for steering. In the present embodiment, the function of determining whether the vehicle has a rear-end risk according to the road surface attachment condition is added to the original function of the ACC. When the current vehicle is in the braking state, the maximum deceleration that can be provided on the road where the current vehicle is located and the target deceleration required by the current vehicle are used as a basis for judging whether there is a risk of rear-end collision, and the existing ACC control process is solved. The problem of poor adhesion and low safety is not considered in the road surface adhesion conditions, which improves the control effect and safety of the vehicle.

In order to clearly illustrate the previous embodiment, the vehicle control system proposed by the present invention will be described below with reference to FIG. 2 through a specific embodiment.

As shown in FIG. 2, the vehicle control system can be divided into three layers: a sensing layer, a decision layer, and an execution layer.

The sensing layer includes an ACU for identifying a road surface adhesion coefficient, a front radar probe installed at an intake grille of the vehicle, a front view camera mounted on the inner rear view mirror, and a side view mounted on a side of the side door. Camera, wheel speed sensor, etc.

The decision-making layer includes the ACC 130, which mainly implements the control functions of the vehicle control system.

The execution layer includes an ESP 140, a Body Control Module (BCM), an Instrument Control Management (ICM), an EPS 150, and the like.

The specific working process of the vehicle control system is as follows:

During the current vehicle in the driving mode, the wheel speed sensor collects the wheel speed information of the wheel and sends it to the ESP 140. After acquiring the wheel speed information of the driving wheel and the driven wheel of the current vehicle, the ESP 140 calculates the current vehicle speed according to the wheel speed information. The information is sent to the ACU 110 via a controller area network (CAN) bus.

The ACU 110 calculates the slip ratio of the drive wheels based on the wheel speed information and the vehicle speed information, wherein the slip ratio of the drive wheels refers to the proportion of the slip components in the wheel motion for characterizing the grip. The calculation method of the slip ratio of the driving wheel is as shown in the formula 1.

Where s is the slip ratio of the drive wheel, u is the vehicle speed, and u _w is the wheel speed.

The ACU 110 then identifies the road surface type and obtains an accurate road surface adhesion coefficient according to the slip ratio of the driving wheel and the centroid acceleration of the current vehicle collected by the acceleration sensor.

Afterwards, the ACU 110 acquires the weight of the current vehicle and the road gradient information collected by the acceleration sensor, such as the angle between the road surface and the horizontal plane, and obtains the vertical component of the current vehicle relative to the road surface according to the slope information and the weight of the vehicle, and then according to the vertical component of the vehicle. The vertical component and the road adhesion coefficient get the maximum deceleration and are sent to the ACC 130 via the CAN bus.

At the same time, the data acquisition device 120 acquires the relative speed, time interval, and the like between the target vehicle and the current vehicle through the pre-radar probe and the forward-looking camera to acquire the first data and transmit the first data to the ACC 130.

After receiving the first data, the ACC 130 determines whether the target vehicle is in a braking state based on the first data. In one embodiment of the invention, the determination can be made by the relative speed of the current vehicle and the target vehicle. Specifically, comparing the relative speed of the current moment with the relative speed of the previous moment, when the relative speed is less than the relative speed of the previous moment, it can be determined that the target vehicle is in the braking state, and the relative speed is greater than the relative speed of the previous moment. At this time, it can be determined that the target vehicle is in an accelerated state.

In another embodiment, the determination can be made by the time interval. Specifically, comparing the first time interval of the current time with the second time interval of the previous time, if the first time interval is less than the second time interval, indicating that the distance between the current vehicle and the target vehicle is reduced, the target may be determined. The vehicle is in a braking state.

Of course, the above two methods can also be combined to improve the accuracy of the judgment. Embodiments of the present invention include, but are not limited to, the above-described method of determining whether a target vehicle is in a braking state.

When the target vehicle is in the braking state, the ACC 130 acquires the target deceleration required by the current vehicle, and the calculation method of the target deceleration is as shown in Formula 2.

Where V ₁ is the instantaneous speed of the current vehicle, V ₂ is the instantaneous speed of the target vehicle, Δt is the predicted period, and a is the calculated target deceleration of the current vehicle.

The ACC 130 receives the maximum deceleration sent by the ACU 110 and compares the maximum deceleration with the target deceleration. If the target deceleration is greater than the maximum deceleration, due to the limitation of the road surface, even if the maximum deceleration that the road can provide is less than the target deceleration, the current vehicle can only decelerate according to the maximum deceleration, which will result in the current The vehicle cannot park before the rear end. In order to prevent the rear end of the ESP 140 of the current vehicle from decelerating at the maximum deceleration, in order to avoid the rear-end collision, the EPS 150 is controlled by controlling the EPS 150 of the current vehicle, and the EPS 150 controls the steering mechanism to turn according to the command of the ACC 130. If the target deceleration is less than the maximum deceleration, the ESP 140 of the current vehicle is controlled to perform the following braking in the current lane with the target deceleration.

Since the deceleration is a vector, in the embodiment of the present invention, when comparing the maximum deceleration with the target deceleration, the absolute value of both is compared. For example, the target deceleration is greater than the maximum deceleration means that the absolute value of the target deceleration is greater than the absolute value of the maximum deceleration.

In order to improve the safety during steering, the ACC 130 can acquire the image information in the target lane to be turned in real time through the side view camera to determine whether there is a side in the target lane according to the image information. vehicle. Wherein, the side vehicle is a vehicle whose distance from the current vehicle is lower than a preset threshold, and the preset threshold may be set according to actual needs.

If there is a side vehicle in the image information, the ACC 130 sends an alert message to the BCM and ICM on the current vehicle. After receiving the warning information, the BCM turns on the danger warning light, and the ICM plays the emergency warning voice, which realizes the visual and audible way to remind the driver of the current vehicle to use the whistle mode to remind the side vehicles to avoid, to avoid traffic accidents and improve The safety when turning.

In order to further improve safety, the corresponding relationship between the road surface adhesion coefficient and the hazard level can be established in advance based on the actual test results. During the braking of the target vehicle, the ACU 110 of the current vehicle continuously detects the road surface adhesion coefficient and transmits it to the ACC 130. The ACC 130 obtains the hazard level corresponding to the current road surface condition by querying the corresponding relationship between the road surface adhesion coefficient and the hazard level to determine whether the hazard level corresponding to the detected road surface adhesion coefficient decreases. If the hazard level drops, the target vehicle is reselected for follow-up in the lane. If the road conditions are not improved, the ACC 130 determines that the hazard level has escalated and then controls the current vehicle to continue to turn.

The vehicle control system proposed by the embodiment of the present invention considers the real-time road surface adhesion coefficient and improves the control effect of the vehicle control system. When it is determined that the current vehicle and the target vehicle have a rear-end collision risk, the steering is performed in time, thereby preventing the road surface from being damaged. The risk of rear-end collision when the vehicle is out of control caused by insufficient estimation of the adhesion situation improves the safety of the vehicle.

In order to achieve the above object, an embodiment of the present invention further provides a vehicle control method.

FIG. 3 is a flowchart of a vehicle control method according to an embodiment of the present invention.

As shown in FIG. 3, the vehicle control method includes:

S301: Acquire a maximum deceleration that the current vehicle is on the road surface.

In an embodiment of the present invention, the maximum deceleration that can be provided by the road surface can be obtained by the road surface adhesion coefficient of the road surface on which the vehicle is currently located and the vertical component force of the current vehicle relative to the road surface.

Specifically, first, the vehicle speed information of the current vehicle is calculated according to the wheel speed information of the driving wheel and the driven wheel of the current vehicle collected by the wheel speed sensor. Then, based on the wheel speed information and the vehicle speed information, the slip ratio of the drive wheels is calculated. According to the slip ratio of the driving wheel and the centroid acceleration of the current vehicle collected by the acceleration sensor, the road surface type is determined by two-dimensional query method and the road surface adhesion coefficient is determined.

At the same time, the slope information of the road surface is obtained by the acceleration sensor, such as the angle between the road surface and the water level, and the vertical component of the current vehicle relative to the road surface is calculated according to the obtained slope information and the weight of the current vehicle.

Finally, according to the road surface adhesion coefficient and the vertical component force, the maximum deceleration that the current vehicle is on is calculated.

S302. Acquire first data including a relative speed and/or a time interval between the target vehicle and the current vehicle.

Wherein, the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle.

In the embodiment of the present invention, the first data such as the relative speed and the time interval between the target vehicle and the current vehicle can be collected by the front radar probe and the front view camera installed at the front air intake grille.

S303. Determine, according to the first data, whether the target vehicle is in a braking state.

In one embodiment of the invention, the determination can be made by the relative speed of the current vehicle and the target vehicle. Specifically, comparing the relative speed of the current moment with the relative speed of the previous moment, when the relative speed is less than the relative speed of the previous moment, it can be determined that the target vehicle is in the braking state, and the relative speed is greater than the relative speed of the previous moment. At this time, it can be determined that the target vehicle is in an accelerated state.

S304: Acquire a target deceleration required by the current vehicle when the target vehicle is in a braking state.

The calculation method of the target deceleration is as shown in the formula 2 in the foregoing embodiment, and details are not described herein again.

S305. Determine, according to the maximum deceleration and the target deceleration, whether the current vehicle has a rear-end risk.

If the target deceleration is greater than the maximum deceleration, it can be determined that there is a risk of rear-end collision between the current vehicle and the target vehicle. In other words, it is necessary to decelerate according to the target deceleration in order to stop the current vehicle before the target vehicle is chased. However, due to the limitation of the road surface, even if the maximum deceleration that the road can provide is less than the target deceleration, the current vehicle can only decelerate according to the maximum deceleration, which will cause the current vehicle to stop before the rear end.

S306, when there is a risk of rear-end collision, control the current vehicle to decelerate the brake at the maximum deceleration and turn.

When the maximum deceleration that the road surface can provide is less than the target deceleration, the current vehicle can only decelerate according to the maximum deceleration due to the limitation of the road conditions. At this time, there is a risk that the current vehicle and the target vehicle have a rear-end collision. In order to reduce the risk of rear-end collision, the current vehicle is controlled to decelerate the brake at the maximum deceleration, and the current vehicle is controlled to turn to other lanes to avoid rear-end collision with the target vehicle in the current lane.

When the target deceleration is less than the maximum deceleration, the current vehicle can be controlled to perform the following vehicle deceleration to perform the following braking in the current lane.

In order to more clearly illustrate the previous embodiment, the vehicle control method proposed by the present invention will be described below by taking an electric vehicle as an example.

As shown in FIG. 4, the vehicle control method includes:

S401, the vehicle control unit (VCU) is initialized.

Wake up the VCU by turning ON ON. After the VCU is woken up, the controller data is initialized and the data in the Electrically Erasable Programmable Read-Only Memory (EEPROM) is read. If an irresistible fault occurs during the last power-up cycle, power-on is prohibited; the data before the vehicle is powered on is integrated, and if there is a power-off fault, the VCU will disable the high voltage on the system.

S402, the VCU wakes up each related controller.

The VCU will judge the vehicle mode, and the vehicle mode includes but is not limited to the remote mode, the driving mode, the slow charging mode, the fast charging mode, and the like. If the vehicle mode is determined to be in the driving mode, the VCU wakes up the Battery Management System (BMS), the BCM, the air conditioner controller, and the like.

S403, the VCU guides the entire vehicle to power on.

The VCU is powered by the high-voltage components of the vehicle to power on the vehicle.

S404, the radar and the camera collect data.

Data is collected based on a front radar probe mounted on the front air intake grille and a front view camera mounted on the inner rearview mirror, such as data such as the distance between the target vehicle and the current vehicle.

S405, obtaining relative speed and time interval.

Based on the data acquired in step S404, the relative speed, time interval, and the like between the current vehicle and the target vehicle are obtained.

S406, the MRR determines the required target deceleration and obtains the maximum deceleration.

Since the front millimeter wave detection controller (MRR) is the core controller of the ACC, the ARC function can be performed by the MRR.

The MRR can determine whether the target vehicle is in a braking state according to the relative speeds of the front and rear vehicles, the time interval, and the like. The determination method is as described in the foregoing embodiment, and details are not described herein again. When the target vehicle is in the braking state, the target deceleration required by the current vehicle is determined, and the calculation method is as shown in the above embodiment. At the same time, obtain the maximum deceleration that the current vehicle is on.

The calculation method of the maximum deceleration is as shown in steps S407-S412.

S407. Collect wheel speed information of the driving wheel and the driven wheel based on the wheel speed sensor.

After acquiring the wheel speed information, the vehicle speed information of the current vehicle is calculated according to the wheel speed information, and the wheel speed information and the vehicle speed information are transmitted to the ACU through the CAN bus.

S408, the ACU calculates the slip ratio of the driving wheel.

The ACU calculates the slip ratio of the driving wheel based on the wheel speed information and the vehicle speed information, and the calculation method is as shown in Formula 1.

S409. Acquire mass center acceleration information based on the acceleration sensor.

S410, the ACU identifies the road surface type by means of two-dimensional query and obtains the road surface adhesion coefficient.

Based on the acquired centroid acceleration information and the slip ratio of the driving wheel, the ACU identifies the road surface type by two-dimensional query and obtains the road surface adhesion coefficient.

S411. Acquire slope information based on the acceleration sensor.

The acquired slope information is sent to the ACU.

S412, the ACU calculates the maximum deceleration that the road surface can provide.

Based on the obtained slope information, the ACU obtains the vertical component of the current vehicle in combination with the weight of the current vehicle. Then, based on the vertical component force and the road surface adhesion coefficient, the maximum deceleration that can be provided by the current vehicle's road surface is calculated, and the maximum deceleration is sent to the MRR through the CAN bus.

S413, the MRR determines whether the target deceleration is less than the maximum deceleration.

The MRR determines whether the target deceleration required for the current vehicle is less than the maximum deceleration obtained from the ACU. If the target deceleration is less than the maximum deceleration, step S415 is performed, and the ACC controls the ESP to perform the following vehicle braking in the current lane with the target deceleration. If the target deceleration is greater than the maximum deceleration, step S414 is performed.

S414, the MRR controls the ESP to brake at a maximum deceleration speed and controls the EPS to perform steering.

There is a risk of rear-end collision because the maximum deceleration that the road can provide is less than the target deceleration. In order to reduce the risk of rear-end collision, the MRR controls the ESP to brake at the maximum deceleration rate, and controls the EPS to turn to the target lane to avoid the rear-end collision between the current vehicle and the target vehicle.

In the process of steering, the MRR can monitor the vehicles in the target lane through the side-view camera. If the side vehicles are found, the driver is prompted to whistle through the BCM and the ICM. For the specific method, refer to the above embodiment, and no further description is provided here. .

S416, the MRR determines whether the danger level corresponding to the road surface adhesion coefficient decreases.

During the steering of the target vehicle, the ACU continuously detects the road surface adhesion coefficient, and the MRR determines whether the danger level corresponding to the road surface adhesion coefficient decreases. If the hazard level is upgraded, continue to control the EPS for steering until the lane is replaced, causing the hazard level to drop.

S417, taking the nearest preceding vehicle in the target lane as the target vehicle.

If the danger level is lowered, the nearest preceding vehicle in the target lane is used as the target vehicle to perform re-following.

It can be seen from Fig. 4 that in the vehicle control process, the road condition is added as the lateral control logic to the control method, which can reduce the risk of rear-end collision caused by insufficient braking of the current vehicle due to insufficient ground adhesion, and improve the safety of the system.

In order to achieve the above object, an embodiment of the present invention provides a vehicle control apparatus including a memory and a processor, wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory, It is used to execute the vehicle control method described in the above embodiments.

In order to achieve the above object, an embodiment of the present invention further provides a computer program product, which is executed when the instructions in the computer program product are executed by the processor.

In order to achieve the above object, an embodiment of the present invention further provides a non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program is executed by a processor to implement the vehicle of the above embodiment. Control Method.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms is not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, various embodiments or examples described in the specification, as well as features of various embodiments or examples, may be combined and combined.

Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include at least one of the features, either explicitly or implicitly. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless specifically defined otherwise.

Any process or method description in the flowcharts or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logic function or process. And the scope of the preferred embodiments of the invention includes additional implementations, in which the functions may be performed in a substantially simultaneous manner or in reverse order depending on the functions involved, in the order shown or discussed. It will be understood by those skilled in the art to which the embodiments of the present invention pertain.

The logic and/or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be embodied in any computer readable medium, Used in conjunction with, or in conjunction with, an instruction execution system, apparatus, or device (eg, a computer-based system, a system including a processor, or other system that can fetch instructions and execute instructions from an instruction execution system, apparatus, or device) Or use with equipment. For the purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport a program for use in an instruction execution system, apparatus, or device, or in conjunction with the instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer readable media include the following: electrical connections (electronic devices) having one or more wires, portable computer disk cartridges (magnetic devices), random access memory (RAM), Read only memory (ROM), erasable editable read only memory (EPROM or flash memory), fiber optic devices, and portable compact disk read only memory (CDROM). In addition, the computer readable medium may even be a paper or other suitable medium on which the program can be printed, as it may be optically scanned, for example by paper or other medium, followed by editing, interpretation or, if appropriate, other suitable The method is processed to obtain the program electronically and then stored in computer memory.

It should be understood that portions of the invention may be implemented in hardware, software, firmware or a combination thereof. In the above-described embodiments, multiple steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware and in another embodiment, it can be implemented by any one or combination of the following techniques well known in the art: discrete with logic gates for implementing logic functions on data signals Logic circuits, application specific integrated circuits with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), and the like.

One of ordinary skill in the art can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by a program to instruct related hardware, and the program can be stored in a computer readable storage medium. When executed, one or a combination of the steps of the method embodiments is included.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The integrated modules, if implemented in the form of software functional modules and sold or used as stand-alone products, may also be stored in a computer readable storage medium.

The above mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like. Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. The embodiments are subject to variations, modifications, substitutions and variations.

Claims

A vehicle control method, comprising:

Obtain the maximum deceleration that the current vehicle is on;

Acquiring first data including a relative speed and/or a time interval between the target vehicle and the current vehicle; wherein the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle;

Determining, according to the first data, whether the target vehicle is in a braking state;

Acquiring a target deceleration required by the current vehicle when the target vehicle is in a braking state;

Determining whether the current vehicle has a rear-end risk according to the maximum deceleration and the target deceleration;

When there is a rear-end risk, the current vehicle is controlled to decelerate the brake and steer at the maximum deceleration.
The vehicle control method according to claim 1, wherein the obtaining the maximum deceleration that the current vehicle is on the road surface comprises:

Obtaining the road surface adhesion coefficient of the road where the current vehicle is located;

The maximum deceleration is obtained according to the road surface adhesion coefficient.
The vehicle control method according to claim 2, wherein the acquiring a road surface adhesion coefficient of a road surface on which the current vehicle is located includes:

Obtaining wheel speed information of the driving wheel and the driven wheel of the current vehicle;

Calculating vehicle speed information of the current vehicle according to the wheel speed information;

Calculating a slip ratio of the driving wheel according to the wheel speed information and the vehicle speed information;

The road surface adhesion coefficient is determined according to a centroid acceleration of the current vehicle and a slip ratio of the drive wheel.
The vehicle control method according to claim 2, wherein the obtaining the maximum deceleration according to the road surface adhesion coefficient comprises:

Obtaining the slope information of the road surface and the weight of the current vehicle;

Obtaining a vertical component of the current vehicle relative to the road surface according to the slope information and the weight;

The maximum deceleration is obtained according to the vertical component force and the road surface adhesion coefficient.
The vehicle control method according to any one of claims 1 to 4, wherein the determining whether the current vehicle has a rear-end risk according to the maximum deceleration and the target deceleration comprises:

Comparing the target deceleration with the maximum deceleration;

If the target deceleration is greater than the maximum deceleration, it is determined that there is a rear-end risk.
The vehicle control method according to any one of claims 1 to 4, wherein the determining whether the target vehicle is in a braking state according to the first data comprises:

Comparing the relative speed with the relative speed of the previous moment;

Determining that the target vehicle is in a braking state when the relative speed is less than a relative speed of a previous moment; or

Comparing the first time interval with a second time interval of a previous time;

If the first time interval is less than the second time interval, it is determined that the target vehicle is in a braking state.
The vehicle control method according to any one of claims 1 to 4, further comprising:

Continuously detecting the road surface adhesion coefficient;

Determining whether the detected danger level corresponding to the road surface adhesion coefficient is decreased;

If the hazard level drops, the target vehicle is reselected for follow-up within the lane.
The vehicle control method according to any one of claims 1 to 4, further comprising:

In the process of controlling the current vehicle steering, real-time acquisition of image information in the target lane to be turned;

Determining, according to the image information, whether there is a side vehicle in the target lane; wherein the side vehicle is a vehicle whose distance from the current vehicle is lower than a preset threshold;

If the side vehicle exists in the image information, controlling the current vehicle to issue an alarm message.
A vehicle control system, comprising:

ACU, used to obtain the maximum deceleration that the current vehicle is on;

a data acquisition device, configured to acquire first data including a relative speed and/or a time interval between the target vehicle and the current vehicle; wherein the target vehicle is a vehicle located in front of the current vehicle and closest to the current vehicle;

An ACC, configured to determine, according to the first data, whether the target vehicle is in a braking state, acquire a target deceleration required by a current vehicle when the target vehicle is in a braking state, and according to the maximum deceleration and Determining the target deceleration, determining whether there is a risk of rear-end collision in the current vehicle, and controlling the ESP of the current vehicle to decelerate the braking at the maximum deceleration and controlling the EPS steering of the current vehicle when determining that there is a risk of rear-end collision;

The ESP is configured to control a current vehicle to decelerate braking at the maximum deceleration according to an instruction of the ACC;

The EPS is configured to control steering steering of a current vehicle according to an instruction of the ACC.
The vehicle control system according to claim 9, wherein the ACU is specifically configured to acquire a road surface adhesion coefficient of a road surface on which the current vehicle is located, and acquire the maximum deceleration speed according to the road surface adhesion coefficient.
The vehicle control system according to claim 10, wherein the ESP is specifically configured to acquire wheel speed information of a driving wheel and a driven wheel of a current vehicle, and calculate vehicle speed information of the current vehicle according to the wheel speed information, and Transmitting the wheel speed information and the vehicle speed information to the ACU;

The ACU is specifically configured to calculate a slip ratio of the driving wheel according to the wheel speed information and the vehicle speed information, and determine the pavement according to a centroid acceleration of a current vehicle and a slip ratio of the driving wheel. Adhesion coefficient.
The vehicle control system according to claim 11, wherein the ACU is configured to acquire the gradient information of the road surface and the weight of the current vehicle, and acquire the current vehicle according to the slope information and the weight. The maximum deceleration is obtained according to the vertical component force and the road surface adhesion coefficient with respect to the vertical component force of the road surface.
The vehicle control system according to any one of claims 9 to 12, wherein the ACC is specifically configured to compare the target deceleration with the maximum deceleration if the target deceleration is greater than When the maximum deceleration is described, it is determined that there is a risk of rear-end collision.
The vehicle control system according to any one of claims 9 to 12, wherein the ACC is specifically used to compare the relative speed with a relative speed of a previous moment, when the relative speed is smaller than a previous moment. Determining, in relative speed, determining that the target vehicle is in a braking state; or comparing the first time interval with a second time interval of a previous time, if the first time interval is less than the second time interval, determining The target vehicle is in a braking state.
The vehicle control system according to any one of claims 9 to 12, wherein the ACU is further configured to continuously detect the road surface adhesion coefficient;

The ACC is further configured to determine whether the detected risk level corresponding to the road surface adhesion coefficient is decreased. If the danger level decreases, the target vehicle is reselected in the lane to follow.
The vehicle control system according to any one of claims 9 to 12, wherein the ACC is further configured to acquire a monitoring video in a target lane to be steered in real time during the process of controlling the current vehicle steering. Determining whether there is a side vehicle in the target lane; wherein the side vehicle is a vehicle whose distance from the current vehicle is lower than a preset threshold, if the side vehicle exists in the surveillance video, The alarm message is sent by the BCM and/or ICM on the current vehicle.
A vehicle control apparatus, comprising: a memory and a processor, wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory to use A vehicle control method according to any one of claims 1-8.
A computer program product for performing the vehicle control method according to any one of claims 1-8 when instructions in the computer program product are executed by a processor.
A non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program is executed by a processor to implement the vehicle control method according to any one of claims 1-8.