CN111038512B - Vehicle deceleration control method and vehicle control unit - Google Patents

Vehicle deceleration control method and vehicle control unit Download PDF

Info

Publication number
CN111038512B
CN111038512B CN201911359166.1A CN201911359166A CN111038512B CN 111038512 B CN111038512 B CN 111038512B CN 201911359166 A CN201911359166 A CN 201911359166A CN 111038512 B CN111038512 B CN 111038512B
Authority
CN
China
Prior art keywords
vehicle
deceleration
speed
target
distance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201911359166.1A
Other languages
Chinese (zh)
Other versions
CN111038512A (en
Inventor
李垚
李祥杰
孔令伟
张军腾
何海
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
United Automotive Electronic Systems Co Ltd
Original Assignee
United Automotive Electronic Systems Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by United Automotive Electronic Systems Co Ltd filed Critical United Automotive Electronic Systems Co Ltd
Priority to CN201911359166.1A priority Critical patent/CN111038512B/en
Publication of CN111038512A publication Critical patent/CN111038512A/en
Application granted granted Critical
Publication of CN111038512B publication Critical patent/CN111038512B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • B60W30/18009—Propelling the vehicle related to particular drive situations
    • B60W30/18109—Braking
    • 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
    • B60W2520/00—Input parameters relating to overall vehicle dynamics
    • B60W2520/10—Longitudinal speed
    • 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
    • B60W2720/00—Output or target parameters relating to overall vehicle dynamics
    • B60W2720/10—Longitudinal speed
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/80—Technologies aiming to reduce greenhouse gasses emissions common to all road transportation technologies
    • Y02T10/84—Data processing systems or methods, management, administration

Landscapes

  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Driving Devices And Active Controlling Of Vehicle (AREA)

Abstract

The invention provides a vehicle deceleration control method and a vehicle controller, wherein the vehicle deceleration control method analyzes whether any deceleration target in a deceleration target set exists in front environment information acquired at each moment so as to judge whether a vehicle driver has an intention of deceleration; then, when the deceleration intention exists, a first deceleration distance traveled by the vehicle to achieve the target speed after the vehicle is completely slid at the vehicle speed after the throttle is released is calculated, and a second deceleration distance traveled by the vehicle to achieve the target speed through the complete motor braking at the vehicle speed is calculated to determine a deceleration mode adopted when the vehicle decelerates and travels; and finally, performing deceleration control on the vehicle in different deceleration stages according to the determined deceleration mode and the mode of taking over control by the driver, so that the vehicle can perform sliding and motor braking recovery actions, and better fuel economy and driving safety are realized.

Description

Vehicle deceleration control method and vehicle control unit
Technical Field
The invention relates to the technical field of automobiles, in particular to a vehicle deceleration control method and a vehicle control unit.
Background
Deceleration is an unavoidable behavior of the driver during driving. Please refer to fig. 1, which shows a relationship curve between a vehicle speed and a driving distance during deceleration of a driver after a front vehicle decelerates in a conventional case. As shown in fig. 1, when a traffic scene such as a red light, an intersection, a speed limit sign and the like exists at the front side and needs to be decelerated, a driver usually selects to brake when the driver is close to a target, namely, the vehicle speed is kept constant at the front half section, and the vehicle speed is quickly reduced to the target vehicle speed when the driver approaches the speed limit target.
For the deceleration process of the driver as above, there is a difference between the fuel automobile and the electric automobile. Please refer to fig. 2, which is a graph of speed versus distance traveled during deceleration of a driver of a fuel-powered vehicle. As shown in fig. 2, the fuel-powered vehicle has no battery to recover energy, and all kinetic energy during braking is dissipated by the friction disks. Aggressive drivers typically brake when they are very close to a target, and energy-efficient drivers brake after coasting for a period of time.
Please refer to fig. 3, which is a graph of a speed versus a driving distance during deceleration of a driver of an electric vehicle. As shown in fig. 3, for example, in the behavior of the driver of the energy-saving electric vehicle, when the driver is far away from the target, the driver releases the accelerator, the vehicle performs the throttle release recovery or the vehicle slides, when the driver is close to the target, the driver steps on the brake, and the brake system and the motor jointly decelerate the vehicle.
At present, the existing vehicle control system cannot control the deceleration behavior and the deceleration process of the driver. When the speed needs to be reduced, different drivers perform sliding or braking actions according to experience, and a large amount of braking actions are necessarily caused. It is a very uneconomical practice for the driver's braking to waste kinetic energy of the vehicle in the friction discs. On the other hand, when the driver releases the throttle, the conventional control method can only make the vehicle in one state of sliding or recovering the throttle. If the control system chooses to release the throttle into coasting, it is dangerous for the driver to release the throttle when the vehicle is close to an obstacle in front. If the control system chooses to recover the pine door entry capability, the vehicle will slow down too early when it is far from the obstacle in front, and the driver will need to accelerate again later.
Aiming at the problems existing in the vehicle deceleration process in the prior art, the technical personnel in the field are always seeking a solution.
Disclosure of Invention
The invention aims to provide a vehicle deceleration control method and a vehicle controller, which are used for solving the problems existing in the vehicle deceleration process in the prior art.
In order to solve the above technical problem, the present invention provides a vehicle deceleration control method, including:
acquiring front environment information, vehicle speed and the relative distance between a vehicle and a deceleration target in the front environment information in real time, and judging whether any deceleration target in a deceleration target set exists in the front environment information acquired at each moment, wherein the deceleration target is a speed limit sign, a traffic light, a rotary island, a front vehicle or a curve;
analyzing all deceleration targets in the deceleration target set existing in the acquired front environment information aiming at each moment to judge whether a vehicle driver has an intention of deceleration;
when the judgment result shows that the driver of the vehicle has the deceleration intention, respectively calculating a first deceleration distance (sc) traveled when the vehicle completely slides to reach the target speed at the vehicle speed after the throttle of the vehicle is released and a second deceleration distance (sr) traveled when the vehicle completely brakes by the motor to reach the target speed at the vehicle speed;
Determining a deceleration mode adopted when the vehicle decelerates to run according to the first deceleration distance (sc) and the second deceleration distance (sr), and prompting a driver of the vehicle to release an accelerator;
and after the accelerator is released by the vehicle driver, performing vehicle deceleration control according to the deceleration mode until the vehicle speed is decelerated to reach a vehicle speed threshold value and/or the relative distance between the vehicle and a deceleration target in the front environment information reaches a distance threshold value, and prompting the vehicle driver to take over the vehicle deceleration control.
Optionally, in the vehicle deceleration control method, the front environment information and the relative distance between the vehicle and the deceleration target existing in the front environment information are obtained based on monitoring of a radar, a camera and navigation configured for the vehicle.
Optionally, in the vehicle deceleration control method, determining whether there is an intention to decelerate the vehicle driver is determined according to the following equation:
flgSpdLmt＝∪flgx(X，v，sact) (1)
in the formula (1), x is a set of deceleration targets, and x is { speed limit sign; a traffic light; a ring island; a preceding vehicle; a bend; x is related information of the deceleration target, and if X is traffic light, X is { traffic light color }; if X is a curve, X is { curvature radius, curve direction }; sactThe relative distance between the vehicle at the current moment and a deceleration target existing in the front environment information is obtained; and v is the vehicle speed at the current moment.
Optionally, in the vehicle deceleration control method, a process of analyzing all deceleration targets in the deceleration target set existing in the acquired front environment information to determine whether the vehicle driver has an intention to decelerate is as follows:
if any deceleration target in the deceleration target set exists in the front environment information at the current moment, the vehicle driver has an intention of deceleration; otherwise, the vehicle driver does not have an intention to decelerate.
Optionally, in the vehicle deceleration control method, the first deceleration distance (sc), the second deceleration distance (sr), the first time (tc), and the second time (tr) are calculated by the following formula:
Figure GDA0003553094210000041
in the formula (2), FrIs the vehicle sliding resistance related to the vehicle speed v; mdragIs the engine drag torque associated with engine speed ne; mgenThe motor braking torque related to the motor rotating speed nm; η is the efficiency of the relevant component; i.e. ioThe engine main reduction ratio; i.e. igIs the engine gear ratio; m is the vehicle mass; delta is a vehicle rotation conversion coefficient;
Figure GDA0003553094210000042
when the engine speed and the motor speed are in a fixed gear, the engine speed and the motor speed are in a proportional relation with the vehicle speed, so that the formula (2) is converted into the following formula:
Figure GDA0003553094210000043
Figure GDA0003553094210000044
Figure GDA0003553094210000045
in the formula (4) and the formula (5), v0 is the vehicle speed when the accelerator is released; v is vehicle speed; v. of tIs the target vehicle speed.
Optionally, in the vehicle deceleration control method, the basis for determining the deceleration mode adopted when the vehicle decelerates to travel according to the first deceleration distance and the second deceleration distance is as follows:
Figure GDA0003553094210000051
wherein the FC mode is a full coast deceleration control mode; the CR mode is a control mode of firstly sliding and then braking and decelerating the motor; the FR mode is a complete motor braking deceleration control mode; sc is a first deceleration distance calculated at the current moment; sr is a second deceleration distance calculated at the current moment; sact is the relative distance between the vehicle acquired at the current moment and a deceleration target existing in the front environment information;
Figure GDA0003553094210000052
the relative distance between the vehicle acquired at the previous moment and the deceleration target existing in the preceding environmental information;
Figure GDA0003553094210000053
a first deceleration distance calculated for a previous time instant.
Optionally, in the vehicle deceleration control method, in the process of performing vehicle deceleration control in the FR mode, the vehicle controller performs motor torque adjustment according to a difference between a relative distance between the vehicle and a deceleration target existing in the environmental information ahead at each time actually acquired after the vehicle is released from the throttle and a travel distance of the vehicle at the corresponding time;
wherein the travel distance calculation formula of the vehicle is as follows:
snow＝∫vfr(v,ig)dv+C(s0,vt)；
Wherein s isnowThe theoretical running distance of the vehicle to the deceleration target at the current vehicle speed; s0 is the relative distance between the vehicle and the deceleration target present in the preceding environmental information when the vehicle is accelerator released; vt is the target vehicle speed; c is a constant term determined by s0 and vt; i.e. igIs the engine gear ratio.
Optionally, in the vehicle deceleration control method, a driver of the vehicle is prompted to release the accelerator based on a double-pulse vibration mode of an active feedback pedal (APM) as a reminding mode.
Optionally, in the vehicle deceleration control method, a vehicle driver is prompted to take over the vehicle deceleration control based on an automobile instrument human-machine interface (HMI).
Optionally, in the vehicle deceleration control method, the vehicle speed threshold is related to a target vehicle speed and a vehicle idle speed; the distance threshold is related to a vehicle speed, a vehicle gear, and a target vehicle speed.
Correspondingly, the invention also provides a vehicle control unit, which comprises: a processor and a memory, the memory having stored therein a computer program; the processor executes the computer program stored in the memory to cause the vehicle control unit to execute the vehicle deceleration control method.
In the vehicle deceleration control method and the vehicle control unit, the vehicle deceleration control method analyzes whether any deceleration target in a deceleration target set exists in the front environment information acquired at each moment so as to judge whether a vehicle driver has an intention of deceleration; then, when a deceleration intention exists, a deceleration mode adopted when the vehicle decelerates to run is determined by calculating a first deceleration distance traveled by the vehicle when the vehicle completely slides to reach a target speed at the vehicle speed after the throttle of the vehicle is released and a second deceleration distance traveled by the vehicle when the vehicle speed completely reaches the target speed through motor braking; and finally, performing deceleration control on the vehicle in different deceleration stages according to the determined deceleration mode and the mode of taking over control by the driver, so that the vehicle can perform sliding and motor braking recovery actions, and better fuel economy and driving safety are realized.
Drawings
FIG. 1 is a graph showing the relationship between the vehicle speed and the driving distance during the deceleration process of a driver after a front vehicle decelerates under the existing conditions;
FIG. 2 is a curve of the relationship between the vehicle speed and the driving distance during the deceleration process of a driver of a fuel-powered vehicle in the prior art;
FIG. 3 is a curve of a relationship between a vehicle speed and a driving distance during a deceleration process of a driver of an electric vehicle in the prior art;
FIGS. 4a and 4b are flow charts of a vehicle deceleration control method according to an embodiment of the present invention;
FIG. 5 is a comparison graph of the relationship between the vehicle speed and the driving distance during the deceleration process of the driver before and after the deceleration control method of the vehicle according to the present invention is applied and the vehicle ahead decelerates;
FIG. 6 is a schematic diagram of a method for controlling deceleration of a vehicle in accordance with the present invention.
Detailed Description
The following describes the vehicle deceleration control method and the vehicle control unit in detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is provided for the purpose of facilitating and clearly illustrating embodiments of the present invention.
The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than the number, shape and size of the components in actual implementation, and the form, quantity and proportion of the components in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.
Certain terms are used throughout the description and claims to refer to particular system components. As one skilled in the art will appreciate, different companies may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the description and claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to …".
As used in this application and the appended claims, the terms "a," "an," "the," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.
Furthermore, each of the embodiments described below has one or more technical features, and thus, the use of the technical features of any one embodiment does not necessarily mean that all of the technical features of any one embodiment are implemented at the same time or that only some or all of the technical features of different embodiments are implemented separately. In other words, those skilled in the art can selectively implement some or all of the features of any embodiment or combinations of some or all of the features of multiple embodiments according to the disclosure of the present invention and according to design specifications or implementation requirements, thereby increasing the flexibility in implementing the invention.
The present invention will be described in more detail with reference to the accompanying drawings, in order to make the objects and features of the present invention more comprehensible, embodiments thereof will be described in detail below, but the present invention may be implemented in various forms and should not be construed as being limited to the embodiments described.
Referring to fig. 4a and 4b, both are flowcharts of the vehicle deceleration control method of the present invention. As shown in fig. 4a and 4b, the vehicle deceleration control method includes the steps of:
firstly, step S1 is executed to obtain the front environment information, the vehicle speed and the relative distance between the vehicle and the deceleration target existing in the front environment information in real time, and determine whether any deceleration target in the deceleration target set exists in the front environment information obtained at each moment, where the deceleration target includes but is not limited to a speed limit sign, a traffic light, a roundabout, a front vehicle or a curve, and may be set as required.
The vehicle speed and acceleration information can be obtained based on the sensor of the vehicle; the method comprises the steps of acquiring front environment information and the relative distance between a vehicle and a deceleration target existing in the front environment information based on monitoring of a radar, a camera and navigation configured on the vehicle, wherein the value of the relative distance can be changed along with the running process of the vehicle all the time.
Next, step S2 is executed to analyze, for each time, all of the deceleration targets in the deceleration target set present in the acquired front environment information to determine whether the vehicle driver has an intention to decelerate.
Specifically, determining whether the vehicle driver has an intention to decelerate is determined according to the following equation:
flgSpdLmt＝∪flgx(X，v，sact) (1)
in the formula (1), x is a set of deceleration targets, and x is { speed limit sign; a traffic light; a rotary island; a preceding vehicle; a bend; x is related information of the deceleration target, and if X is traffic light, X is { traffic light color }; if X is a curve, X is [ curvature radius, curve direction }; sact is the relative distance between the vehicle at the current moment and a deceleration target existing in the front environment information; and v is the vehicle speed at the current moment.
The Chinese meaning represented by formula (1) is: as long as any one of the deceleration targets in the deceleration target set exists in the front environment information acquired at the current moment (that is, as long as one deceleration target exists in the front environment information), the vehicle driver has an intention to decelerate; otherwise, the vehicle driver does not have an intention to decelerate.
Then, step S3 is executed to calculate a first deceleration distance S, which is a distance traveled by the vehicle to completely slide at the vehicle speed to reach the target vehicle speed after the vehicle releases the throttle, when the driver of the vehicle has an intention to decelerate as a result of the determination cAnd a second deceleration distance s traveled by the full motor braking at the vehicle speed to the target vehicle speedr(ii) a Wherein the first deceleration distance s is calculatedcSecond deceleration distance srThe formula is adopted as follows:
Figure GDA0003553094210000101
in the formula (2), FrThe vehicle sliding resistance related to the vehicle speed v can be obtained through vehicle speed fitting; mdragIs equal to the engine speed neThe relevant engine drag torque can be obtained by engine speed fitting; mgenIs equal to the motor speed nmThe related motor braking torque can be obtained by fitting the external characteristics of the motor and the rotating speed of the motor; η is the efficiency of the relevant component; i.e. ioThe engine main reduction ratio; i.e. igIs the engine gear ratio; m is the vehicle mass; delta is a vehicle rotation conversion coefficient;
Figure GDA0003553094210000106
when the engine speed and the motor speed are in a fixed gear, the engine speed and the motor speed are in a proportional relation with the vehicle speed, so that the formula (2) is converted into the following formula:
Figure GDA0003553094210000103
Figure GDA0003553094210000104
Figure GDA0003553094210000105
in the formulas (4) and (5), v0The initial speed of the vehicle when the accelerator is released; v is vehicle speed; v. oftIs the target vehicle speed.
Then, step S4 is executed to determine the first deceleration distance ScAnd the second deceleration distance srAnd determining a deceleration mode adopted when the vehicle decelerates to run, and prompting a driver of the vehicle to release the accelerator.
In particular, according to said first deceleration distance s cAnd said second deceleration distance srDetermining deceleration of vehicleThe deceleration pattern used is based on:
Figure GDA0003553094210000111
wherein, the FC mode is a full coasting deceleration control mode; the CR mode is a first-sliding and then-motor braking deceleration control mode; the FR mode is a complete motor braking deceleration control mode; scA first deceleration distance calculated for the current time; srA second deceleration distance calculated for the current time; sactObtaining the relative distance between the vehicle and a deceleration target existing in the front environment information at the current moment;
Figure GDA0003553094210000112
the relative distance between the vehicle acquired at the previous moment and the deceleration target existing in the preceding environmental information;
Figure GDA0003553094210000113
a first deceleration distance calculated for a previous time instant.
In this embodiment, the driver of the vehicle is prompted to release the throttle based primarily on an active feedback pedal (APM). The active feedback pedal has multiple modes, including single-pulse vibration, double-pulse vibration, variable pressure pedal and other modes. When a driver feels that the APM regularly vibrates to remind, the accelerator is loosened; if the driver does not release the accelerator all the time, the APM stops vibrating after vibrating for a period of time.
And step S5 is executed, after the accelerator is released by the vehicle driver, the vehicle speed reduction control is carried out according to the speed reduction mode until the vehicle speed is reduced to reach a vehicle speed threshold value and/or the relative distance between the vehicle and a speed reduction target in the front environment information reaches a distance threshold value, and the vehicle driver is prompted to take over the vehicle speed reduction control. Specifically, the vehicle speed threshold is related to a target vehicle speed and a vehicle idle speed, and the vehicle speed threshold is usually set to be close to the target vehicle speed; the distance threshold is related to vehicle speed, vehicle gear, and target vehicle speed, and typically the vehicle travels near the deceleration target when the relative distance reaches the distance threshold. Preferably based on a vehicle instrument Human Machine Interface (HMI) to prompt the vehicle driver to take over control of vehicle deceleration.
S5 will be described in detail by taking the deceleration mode as FC mode, FR mode and CR mode as examples, and refer to fig. 4b specifically.
As shown in fig. 4b, if the deceleration mode is FC mode, the driver releases the throttle, and then triggers the vehicle to disconnect the clutch or enter neutral, the vehicle performs free-wheeling, when it is detected that the vehicle is too close to the target deceleration distance or the vehicle speed is low, the driver is reminded to take over the deceleration control of the vehicle, and the vehicle has coasted as expected by the first deceleration distance scAnd when the target speed is reached, the vehicle speed reaches the target speed, and the engine keeps idling in the whole process.
As shown in fig. 4b, if the deceleration mode is the FR mode, the vehicle directly enters the motor braking energy recovery state after the driver releases the throttle. The vehicle control unit can be used for controlling the relative distance s between the vehicle accelerator releasing moment and the deceleration target0And a target vehicle speed vtAn ideal travel locus of the vehicle (corresponding to the black dotted line shown in fig. 6) is calculated and expressed by the following formula:
snow＝∫vfr(v,ig)dv+C(s0,vt) (ii) a Wherein s isnowThe theoretical running distance of the vehicle to the deceleration target at the current vehicle speed; s0The relative distance between the vehicle and a deceleration target existing in the front environment information when the vehicle releases the throttle; v. oftA target vehicle speed; c is a group s 0And vtA determined constant term; i.e. igIs the engine gear ratio.
In order to enable the vehicle to reach the deceleration point according to the preset distance and the vehicle speed, in the process of performing vehicle deceleration control by adopting the FR mode, the vehicle control unit actually acquires the difference value (i.e. s) between the relative distance between the vehicle and the deceleration target existing in the front environment information and the running distance of the vehicle at the corresponding moment according to the relative distance between the vehicle and the deceleration target at each moment after the vehicle is released from the throttle and the running distance of the vehicle at the corresponding momentact-snow) And adjusting the torque of the motor.
In the FR mode, the motor brake cannot be fully relied on to reach the deceleration point, and the driver is also required to step on the brake with one foot, i.e. the subsequent driver takes over the operation of deceleration control. The FR mode has the significance that most of kinetic energy in the first half can be recycled, and the speed of the vehicle is rapidly reduced, so that energy is saved, and safety is guaranteed.
As shown in fig. 4b, if the deceleration mode adopts the CR mode, after the driver releases the throttle, the vehicle enters the natural coasting state, the vehicle controller calculates that the vehicle reaches the switching point of the natural coasting and the motor braking (i.e., the intersection of the black solid line and the black dashed line in fig. 6), the vehicle is switched from the free coasting state to the motor braking state, and then the vehicle running trajectory runs according to the black dashed line.
Referring to fig. 5 and 6, unlike the conventional vehicle control system that cannot control the deceleration behavior and the deceleration process of the driver, the present invention can determine the deceleration timing according to the front environment information, remind the driver to release the throttle for deceleration, and perform an appropriate deceleration process according to different situations. The vehicle deceleration control method can avoid unnecessary acceleration behavior of a driver, reduce engine oil injection in the driving process, avoid unnecessary friction braking process, maximally recover vehicle kinetic energy in the deceleration process, and improve the oil consumption of the whole vehicle. In addition, the invention can bring better driving performance and safety.
It should be noted that the vehicle deceleration control method of the invention is suitable for vehicles equipped with motors, power release devices, radars, cameras and navigation, and the motors can perform assistance or energy recovery; the power disconnecting device can realize the sliding function of the vehicle; radar, camera and navigation can acquire the forward environment information. The vehicle can be a hybrid electric vehicle or a pure electric vehicle. The vehicle slides freely in a way of disconnecting a clutch or neutral gear in the process of deceleration control, and energy is recovered through motor braking.
In another embodiment, a vehicle control unit is provided, which includes: a processor and a memory, the memory having a computer program stored therein; the processor executes the computer program stored in the memory to cause the vehicle control unit to execute the vehicle deceleration control method, so that the vehicle provided with the vehicle control unit performs deceleration control on the vehicle.
In summary, in the vehicle deceleration control method and the vehicle controller provided by the present invention, the vehicle deceleration control method analyzes whether any deceleration target in the deceleration target set exists in the front environment information acquired at each moment, so as to determine whether the driver of the vehicle intends to decelerate; then, when the deceleration intention exists, a first deceleration distance traveled by the vehicle to achieve the target speed after the vehicle is completely slid at the vehicle speed after the throttle is released is calculated, and a second deceleration distance traveled by the vehicle to achieve the target speed through the complete motor braking at the vehicle speed is calculated to determine a deceleration mode adopted when the vehicle decelerates and travels; and finally, performing deceleration control on the vehicle in different deceleration stages according to the determined deceleration mode and the mode of taking over control by the driver, so that the vehicle can perform sliding and motor braking recovery actions, and better fuel economy and driving safety are realized.
The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims (10)

1. A vehicle deceleration control method characterized by comprising:
acquiring front environment information, vehicle speed and the relative distance between a vehicle and a deceleration target in the front environment information in real time, and judging whether any deceleration target in a deceleration target set exists in the front environment information acquired at each moment, wherein the deceleration target is a speed limit sign, a traffic light, a rotary island, a front vehicle or a curve;
analyzing all deceleration targets in the deceleration target set existing in the acquired front environment information aiming at each moment to judge whether a vehicle driver has an intention of deceleration;
when the judgment result shows that the driver of the vehicle has the deceleration intention, the vehicle speed is completely slipped after the throttle of the vehicle is releasedA first deceleration distance(s) traveled to reach the target vehicle speedc) And a second deceleration distance(s) traveled to achieve the target vehicle speed with full motor braking at the vehicle speed r)；
According to said first deceleration distance(s)c) And said second deceleration distance(s)r) Determining a deceleration mode adopted when the vehicle decelerates to run, and prompting a driver of the vehicle to loosen an accelerator;
after the accelerator is released by a vehicle driver, performing vehicle deceleration control according to the deceleration mode until the vehicle speed is decelerated to reach a vehicle speed threshold value and/or the relative distance between the vehicle and a deceleration target existing in the front environment information reaches a distance threshold value, and prompting the vehicle driver to take over the vehicle deceleration control;
the basis for determining the deceleration mode adopted when the vehicle decelerates to run according to the first deceleration distance and the second deceleration distance is as follows:
Figure FDA0003553094200000011
wherein the FC mode is a full coast deceleration control mode; the CR mode is a control mode of firstly sliding and then braking and decelerating the motor; the FR mode is a complete motor braking deceleration control mode; s iscA first deceleration distance calculated for the current time; srA second deceleration distance calculated for the current time; sactObtaining the relative distance between the vehicle and a deceleration target existing in the front environment information at the current moment;
Figure FDA0003553094200000021
the relative distance between the vehicle acquired at the previous moment and the deceleration target existing in the preceding environmental information;
Figure FDA0003553094200000022
a first deceleration distance calculated for a previous time instant.
2. The vehicle deceleration control method according to claim 1, characterized in that the preceding environment information and the relative distance of the vehicle from the deceleration target present in the preceding environment information are acquired based on monitoring of a radar, a camera, and navigation of the vehicle configuration.
3. The vehicle deceleration control method according to claim 1, characterized in that the determination as to whether there is an intention of deceleration of the vehicle driver is determined according to the following equation:
flgSpdLmt＝∪flgx(X，v，sact) (1)
in the formula (1), x is a deceleration target set, and x is { speed limit sign; a traffic light; a rotary island; a preceding vehicle; a bend; x is related information of the deceleration target, and if X is traffic light, X is { green light color }; if X is a curve, X is { curvature radius, curve direction }; sactThe relative distance between the vehicle at the current moment and a deceleration target existing in the front environment information is obtained; and v is the vehicle speed at the current moment.
4. The vehicle deceleration control method according to claim 1, characterized in that the process of analyzing, for each time, all of the deceleration targets in the deceleration target set present in the acquired front environment information to determine whether there is an intention of deceleration of the vehicle driver is as follows:
if any deceleration target in the deceleration target set exists in the front environment information at the current moment, the vehicle driver has an intention of deceleration; otherwise, the vehicle driver does not have an intention to decelerate.
5. The vehicle deceleration control method according to claim 1, characterized in that the first deceleration distance(s) is calculatedc) The second deceleration distance(s)r) First time (t)c) And a second time (t)r) The following formula is adopted:
Figure FDA0003553094200000031
in the formula (2), FrIs the vehicle sliding resistance related to the vehicle speed v; mdragIs equal to the engine speed neThe associated engine drag torque; mgenIs equal to the motor speed nmThe associated motor braking torque; η is the efficiency of the relevant component; i.e. ioThe engine main reduction ratio; i.e. igIs the engine gear ratio; m is the vehicle mass; delta is a vehicle rotation conversion coefficient;
Figure FDA0003553094200000032
when the engine speed and the motor speed are in a fixed gear, the engine speed and the motor speed are in a proportional relation with the vehicle speed, so that the formula (2) is converted into the following formula:
Figure FDA0003553094200000033
Figure FDA0003553094200000034
Figure FDA0003553094200000035
in the formulas (4) and (5), v0The vehicle speed is the vehicle speed when the accelerator is released; v is vehicle speed; v. oftIs the target vehicle speed.
6. The vehicle deceleration control method according to claim 1, characterized in that, in performing the vehicle deceleration control in the FR mode, the vehicle control unit performs the motor torque adjustment according to a difference between a relative distance between the vehicle and a deceleration target present in the front environment information, which is actually acquired at each time after the vehicle is released from the throttle, and a travel distance of the vehicle at the corresponding time;
Wherein the travel distance calculation formula of the vehicle is as follows:
snow＝∫vfr(v,ig)dv+C(s0,vt)；
wherein s isnowThe theoretical running distance of the vehicle to the deceleration target at the current vehicle speed; s0The relative distance between the vehicle and a deceleration target existing in the front environment information when the vehicle releases the throttle; v. oftA target vehicle speed; c is a group s0And vtA determined constant term; i.e. igIs the engine gear ratio.
7. A vehicle deceleration control method according to claim 1, characterized in that the driver of the vehicle is prompted to release the throttle as a warning based on a double pulse vibration pattern of an active feedback pedal (APM).
8. The vehicle deceleration control method according to claim 1, wherein the vehicle driver is prompted to take over the vehicle deceleration control based on an automobile instrument Human Machine Interface (HMI).
9. The vehicle deceleration control method according to claim 1, characterized in that the vehicle speed threshold value is related to a target vehicle speed and a vehicle idle speed; the distance threshold is related to a vehicle speed, a vehicle gear, and a target vehicle speed.
10. A vehicle control unit, comprising: a processor and a memory, the memory having stored therein a computer program; the processor executes the computer program stored in the memory to cause the hybrid vehicle controller to execute the vehicle deceleration control method according to any one of claims 1 to 9.
CN201911359166.1A 2019-12-25 2019-12-25 Vehicle deceleration control method and vehicle control unit Active CN111038512B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911359166.1A CN111038512B (en) 2019-12-25 2019-12-25 Vehicle deceleration control method and vehicle control unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911359166.1A CN111038512B (en) 2019-12-25 2019-12-25 Vehicle deceleration control method and vehicle control unit

Publications (2)

Publication Number Publication Date
CN111038512A CN111038512A (en) 2020-04-21
CN111038512B true CN111038512B (en) 2022-06-28

Family

ID=70239755

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911359166.1A Active CN111038512B (en) 2019-12-25 2019-12-25 Vehicle deceleration control method and vehicle control unit

Country Status (1)

Country Link
CN (1) CN111038512B (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113561784B (en) * 2020-11-25 2023-07-21 长城汽车股份有限公司 Method and device for guiding energy recovery intensity of vehicle
CN112455436A (en) * 2020-11-27 2021-03-09 联合汽车电子有限公司 Vehicle deceleration control method and vehicle control unit
CN112660130A (en) * 2020-12-31 2021-04-16 联合汽车电子有限公司 New energy automobile sliding control system and method based on intelligent networking information and new energy automobile
CN115675468A (en) * 2021-03-31 2023-02-03 华为技术有限公司 Vehicle control method and device
CN115107525A (en) * 2022-01-14 2022-09-27 长城汽车股份有限公司 Automobile self-adaptive energy recovery method and device and automobile
CN114941710B (en) * 2022-05-12 2024-03-01 上海伯镭智能科技有限公司 Unmanned mining vehicle gear switching control method
CN114801761A (en) * 2022-06-08 2022-07-29 中国第一汽车股份有限公司 Vehicle sliding control method and device, vehicle and storage medium

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105501222A (en) * 2014-10-13 2016-04-20 现代自动车株式会社 Device and method for guiding driver to enter coast driving of eco-friendly vehicle
CN107949513A (en) * 2015-09-01 2018-04-20 日产自动车株式会社 Vehicle travel control method and controlling device for vehicle running
CN109131305A (en) * 2017-06-28 2019-01-04 现代自动车株式会社 The control method slided for environment-friendly type vehicle
CN109803866A (en) * 2016-09-21 2019-05-24 世倍特集团有限责任公司 The determination of the best start in the decelerating phase in rear end
CN110027542A (en) * 2018-01-04 2019-07-19 本田技研工业株式会社 Control device and control method
CN110126810A (en) * 2018-02-09 2019-08-16 本田技研工业株式会社 Automatic driving vehicle and control method for vehicle
CN110525419A (en) * 2018-05-23 2019-12-03 现代自动车株式会社 The torque distribution formula inertia traveling control method of environmentally friendly vehicle
CN110588656A (en) * 2019-09-30 2019-12-20 的卢技术有限公司 Self-adaptive kinetic energy recovery method and system based on road and road condition information

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102564511B (en) * 2011-12-09 2015-08-19 联合汽车电子有限公司 Evaluation algorithms is driven in fuel-economizing for acceleration and deceleration process
GB2567009A (en) * 2017-10-02 2019-04-03 Jaguar Land Rover Ltd Method of assisting in the control of a prime mover of a vehicle, apparatus for assisting in the control of a prime mover of a vehicle, and a vehicle
CN108556846B (en) * 2017-12-27 2020-03-06 潍柴动力股份有限公司 Control method and control system for recovering braking and sliding energy of vehicle

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105501222A (en) * 2014-10-13 2016-04-20 现代自动车株式会社 Device and method for guiding driver to enter coast driving of eco-friendly vehicle
CN107949513A (en) * 2015-09-01 2018-04-20 日产自动车株式会社 Vehicle travel control method and controlling device for vehicle running
CN109803866A (en) * 2016-09-21 2019-05-24 世倍特集团有限责任公司 The determination of the best start in the decelerating phase in rear end
CN109131305A (en) * 2017-06-28 2019-01-04 现代自动车株式会社 The control method slided for environment-friendly type vehicle
CN110027542A (en) * 2018-01-04 2019-07-19 本田技研工业株式会社 Control device and control method
CN110126810A (en) * 2018-02-09 2019-08-16 本田技研工业株式会社 Automatic driving vehicle and control method for vehicle
CN110525419A (en) * 2018-05-23 2019-12-03 现代自动车株式会社 The torque distribution formula inertia traveling control method of environmentally friendly vehicle
CN110588656A (en) * 2019-09-30 2019-12-20 的卢技术有限公司 Self-adaptive kinetic energy recovery method and system based on road and road condition information

Also Published As

Publication number Publication date
CN111038512A (en) 2020-04-21

Similar Documents

Publication Publication Date Title
CN111038512B (en) Vehicle deceleration control method and vehicle control unit
CN106467107B (en) Method for controlling vehicle
US11524686B2 (en) Method of controlling a prime mover of a vehicle, apparatus for controlling a prime mover of a vehicle, and a vehicle comprising such an apparatus
US8340882B2 (en) Method of controlling drive request torque in hybrid electric vehicle
JP2017028750A (en) Vehicular control apparatus
JP2017028749A (en) Vehicular control apparatus
JP6553469B2 (en) Vehicle control device
EP0962352A3 (en) Drive power control device for hybrid vehicle
US11124174B2 (en) Vehicle control system
CN112455436A (en) Vehicle deceleration control method and vehicle control unit
CN108025735B (en) Vehicle control device
JP2017022911A (en) Vehicular control apparatus
EP2907698A1 (en) Brake lamp control device
KR101048142B1 (en) Regenerative braking torque control device and method for hybrid vehicle
JP2008179232A (en) Hybrid vehicle
CN110167812B (en) Method for operating a motor vehicle by an early restart of the engine from engine stall coasting
CN111038275A (en) Control method and device for limiting overspeed of pure electric vehicle
WO2000069665A1 (en) Vehicle running control device and vehicle
JP2012244751A (en) Driving control device
US8628450B2 (en) Vehicular power transmission control apparatus
US11565694B2 (en) Cruise control method for hybrid vehicle
KR102579862B1 (en) Vehicle having electric motor and method of driving controlling for the same
CN111542464B (en) Vehicle control method and vehicle control device
KR102422141B1 (en) Hybrid vehicle and method of controlling thereof
CN108349487B (en) Hybrid vehicle and control method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant