CN109693669B - Method and system for determining nearest on-path front vehicle - Google Patents

Method and system for determining nearest on-path front vehicle Download PDF

Info

Publication number
CN109693669B
CN109693669B CN201811639283.9A CN201811639283A CN109693669B CN 109693669 B CN109693669 B CN 109693669B CN 201811639283 A CN201811639283 A CN 201811639283A CN 109693669 B CN109693669 B CN 109693669B
Authority
CN
China
Prior art keywords
vehicle
motion information
curvature
path
nearest
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
CN201811639283.9A
Other languages
Chinese (zh)
Other versions
CN109693669A (en
Inventor
李继扬
颜学术
李锦明
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.)
Beijing Jingwei Hirain Tech Co Ltd
Original Assignee
Beijing Jingwei Hirain Tech 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 Beijing Jingwei Hirain Tech Co Ltd filed Critical Beijing Jingwei Hirain Tech Co Ltd
Priority to CN201811639283.9A priority Critical patent/CN109693669B/en
Publication of CN109693669A publication Critical patent/CN109693669A/en
Application granted granted Critical
Publication of CN109693669B publication Critical patent/CN109693669B/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
    • B60W30/14—Adaptive cruise control
    • 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
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/02—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to ambient conditions
    • B60W40/06—Road conditions
    • B60W40/072—Curvature of the road
    • 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
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
    • 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
    • B60W2520/00—Input parameters relating to overall vehicle dynamics
    • B60W2520/14—Yaw
    • 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
    • B60W2554/00—Input parameters relating to objects
    • B60W2554/80—Spatial relation or speed relative to objects
    • 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
    • B60W2554/00—Input parameters relating to objects
    • B60W2554/80—Spatial relation or speed relative to objects
    • B60W2554/801—Lateral distance
    • 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
    • B60W2554/00—Input parameters relating to objects
    • B60W2554/80—Spatial relation or speed relative to objects
    • B60W2554/804—Relative longitudinal speed

Landscapes

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

Abstract

When the acquired lane line information is determined to be invalid, the motion information of the front vehicle of the vehicle is converted into a coordinate system of the constant-curvature running path of the vehicle, the relative motion information of the front vehicle relative to the constant-curvature running path of the vehicle is obtained, and the nearest front vehicle of the vehicle is determined based on the running speed of the vehicle and the relative motion information of the front vehicle relative to the constant-curvature running path of the vehicle so as to control the longitudinal speed of the vehicle. The invention realizes that the nearest vehicle ahead of the vehicle is determined under the condition that the lane line information is invalid by converting the motion information of the vehicle ahead into the coordinate system of the constant-curvature running path of the vehicle, and is simultaneously suitable for the condition that the vehicle is in a straight line and a curve track.

Description

Method and system for determining nearest on-path front vehicle
Technical Field
The invention relates to the technical field of automatic driving of automobiles, in particular to a method and a system for determining a nearest vehicle ahead of a route.
Background
An Adaptive Cruise Control (ACC) system is a new generation of assistant driving system developed on the basis of traditional Cruise Control, not only has all functions of automatic Cruise, but also can monitor the road traffic environment in front of an automobile through sensors such as a vehicle-mounted radar and the like. Once other vehicles ahead of the current driving lane are found, which are close to the current driving lane, the longitudinal speed of the vehicles is controlled by controlling the accelerator and the brake of the vehicles according to the information such as the relative distance and the relative speed between the current driving lane and the vehicles ahead, so that the current driving lane and the vehicles ahead keep a proper safe distance.
At present, when the vehicle is a straight-line driving path, under the condition that the lane line information exists, the nearest vehicle in front of the vehicle can be accurately determined simply according to the longitudinal distance between the vehicle and the vehicle in front of the same path. However, when the traveling path of the host vehicle is a straight line without lane line information or when the traveling path of the host vehicle is a curved track, there is a large deviation in determining the nearest preceding vehicle of the host vehicle simply from the longitudinal distance between the host vehicle and the preceding vehicle.
Disclosure of Invention
In view of the above, the present invention discloses a method and a system for determining a vehicle in front of a nearest path, so as to determine the vehicle in front of the nearest path of the vehicle even if lane line information is invalid, and the solution is applicable to the case where the vehicle is in a straight line and a curved track.
A method of determining a nearest in-path vehicle, comprising:
acquiring motion information of a vehicle, and recording the motion information as first motion information, wherein the first motion information comprises: the method comprises the following steps of obtaining motion information of a front vehicle of the vehicle according to a running speed and a yaw rate, and recording the motion information as second motion information, wherein the second motion information comprises: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the vehicle, and acquiring lane line information;
judging whether the lane line information is valid or not;
if not, obtaining the curvature radius of the vehicle running path with the fixed curvature based on the first motion information;
based on the curvature radius, converting the second motion information into a coordinate system of the vehicle constant-curvature running path to obtain relative motion information of the front vehicle relative to the vehicle constant-curvature running path, wherein the relative motion information comprises: longitudinal curve distance, transverse straight line distance and longitudinal speed;
and determining the nearest vehicle in front of the vehicle based on the running speed and the relative motion information of the vehicle.
Optionally, the process of obtaining the curvature radius R of the vehicle running path with constant curvature based on the first motion information is as follows:
R＝VehSpd/Yawrate；
wherein VehSpd is the driving speed and Yawrate is the yaw rate.
Optionally, based on the curvature radius, converting the second motion information to a coordinate system of the vehicle constant-curvature traveling path to obtain relative motion information of the leading vehicle with respect to the vehicle constant-curvature traveling path, which specifically includes:
calculating to obtain the transverse position deviation y between the vehicle and the front vehicle in the constant-curvature running path of the vehicleoffsetThe process is as follows:
y。ffset＝abs(R-y)；
wherein abs (R-y) is a function of the absolute value of the difference between (R-y), and y is the lateral distance between the leading vehicle and the host vehicle;
calculating to obtain an included angle theta between a connecting line of the center of the front vehicle and the circle center of the constant-curvature running path of the vehicle and the horizontal direction, wherein the process is as follows:
θ＝arctan(x/yoffset)；
wherein x is the longitudinal distance between the front vehicle and the vehicle;
calculating to obtain the longitudinal curve distance x of the front vehicle relative to the constant-curvature running path of the vehiclealignThe process is as follows:
xalign＝abs(R)×θ；
wherein abs (R) is a function of the absolute value of R;
calculating to obtain the transverse straight-line distance y of the front vehicle relative to the constant-curvature running path of the vehiclealignThe process is as follows:
Figure BDA0001930801290000031
wherein sign (R) is a sign function of the radius of curvature R;
calculating to obtain the longitudinal speed v of the front vehicle relative to the constant-curvature running path of the self vehiclex_alignThe process is as follows:
vx_align＝vx·cosθ+vy·sinθ·sign(R)；
wherein v isxIs the longitudinal relative speed, v, of the leading vehicle and the own vehicleyThe transverse relative speed of the front vehicle and the vehicle is obtained.
Optionally, the determining, based on the traveling speed and the relative motion information of the host vehicle, a nearest vehicle ahead of the host vehicle in the path includes:
when the running speed of the vehicle is in a preset speed interval, comparing the longitudinal curve distance of the front vehicle relative to the constant-curvature running path of the vehicle, and determining the front vehicle with the shortest longitudinal curve distance as the nearest front vehicle in the path of the vehicle, wherein the maximum speed value in the preset speed interval is a speed threshold value.
Optionally, the determining, based on the traveling speed and the relative motion information of the host vehicle, a nearest vehicle ahead of the host vehicle in the path includes:
when the running speed of the vehicle is greater than the speed threshold value, calculating the longitudinal collision time of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle, wherein the process is as follows:
ttcx＝xalign/vx_align；
wherein ttcxAs the longitudinal collision time, xalignFor the longitudinal curve distance, v, of the leading vehicle relative to the path of constant curvature of the vehiclex_alignThe longitudinal speed of the front vehicle relative to the vehicle constant-curvature running path is obtained;
and comparing the calculated longitudinal collision time, and determining the front vehicle with the shortest longitudinal collision time as the nearest front vehicle in the path of the vehicle.
Optionally, the determining, based on the traveling speed and the relative motion information of the host vehicle, a nearest vehicle ahead of the host vehicle includes:
according to the running speed and the relative motion information of the vehicle, increasing the characteristic value of the front vehicle with the shortest longitudinal collision time by a preset amplitude value, and simultaneously reducing the characteristic value of the front vehicle with the shortest non-longitudinal collision time by the preset amplitude value;
and selecting the front vehicle with the largest characteristic value as the nearest front vehicle in the path of the vehicle.
Optionally, the selecting the leading vehicle with the largest feature value as the nearest leading vehicle on the path of the vehicle includes:
counting the number of times that each preceding vehicle becomes the nearest preceding vehicle in the adjacent period after the adjacent period of the preset number is finished, and rejecting the preceding vehicle of which the occurrence number is lower than the preset number and the characteristic value after the adjacent period of the preset number is finished is not the maximum value in the characteristic values of each preceding vehicle;
and selecting the front vehicle with the maximum characteristic value after the preset number of adjacent cycles are ended as the nearest front vehicle in the path of the vehicle.
A system for determining a nearest in-path vehicle, comprising:
an obtaining unit, configured to obtain motion information of a host vehicle, and record the motion information as first motion information, where the first motion information includes: the method comprises the following steps of obtaining motion information of a front vehicle of the vehicle according to a running speed and a yaw rate, and recording the motion information as second motion information, wherein the second motion information comprises: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the vehicle, and acquiring lane line information;
the first judging unit is used for judging whether the lane line information is valid or not;
a curvature radius obtaining unit configured to obtain a curvature radius of the vehicle constant-curvature traveling path based on the first motion information when the first determination unit determines that the vehicle is not traveling;
a relative motion information obtaining unit, configured to convert the second motion information into a coordinate system of the vehicle constant-curvature traveling path based on the curvature radius, and obtain relative motion information of the leading vehicle relative to the vehicle constant-curvature traveling path, where the relative motion information includes: longitudinal curve distance, transverse straight line distance and longitudinal speed;
a first nearest leading vehicle determination unit configured to determine a nearest leading vehicle of the host vehicle based on the traveling speed of the host vehicle and the relative motion information.
Optionally, the nearest ahead-of-path vehicle determining unit is specifically configured to:
when the running speed of the vehicle is in a preset speed interval, comparing the longitudinal curve distance of the front vehicle relative to the constant-curvature running path of the vehicle, and determining the front vehicle with the shortest longitudinal curve distance as the nearest front vehicle in the path of the vehicle, wherein the maximum speed value in the preset speed interval is a speed threshold value.
Optionally, the first nearest leading vehicle determining unit includes:
the numerical value adjusting subunit is configured to increase the characteristic value of the preceding vehicle with the shortest longitudinal collision time by a preset amplitude value according to the running speed and the relative motion information of the vehicle, and decrease the characteristic value of the preceding vehicle with the shortest non-longitudinal collision time by the preset amplitude value;
and the selecting subunit is used for selecting the front vehicle with the largest characteristic value as the nearest front vehicle in the path of the vehicle.
As is apparent from the above description, the present invention discloses a method and system for determining a nearest leading vehicle, in which, when it is determined that acquired lane line information is invalid, motion information of a leading vehicle of a host vehicle is converted into a coordinate system of a constant-curvature travel path of the host vehicle, relative motion information of the leading vehicle with respect to the constant-curvature travel path of the host vehicle is obtained, and the nearest leading vehicle of the host vehicle is determined based on a travel speed of the host vehicle and relative motion information of the leading vehicle with respect to the constant-curvature travel path of the host vehicle, so as to control a longitudinal speed of the host vehicle. Therefore, the invention can be seen in that the motion information of the front vehicle of the vehicle is converted into the coordinate system of the constant-curvature running path of the vehicle, so that the nearest front vehicle of the vehicle is determined under the condition that the lane line information is invalid, and the scheme is simultaneously suitable for the condition that the vehicle is in a straight line and a curve track.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the disclosed drawings without creative efforts.
FIG. 1 is a flowchart of a method for determining a nearest vehicle ahead of a route according to an embodiment of the present disclosure;
FIG. 2 is a schematic diagram of distance conversion of a leading vehicle when the vehicle is in a curved track according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a system for determining a nearest vehicle ahead of a route according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
When the acquired lane line information is determined to be invalid, the motion information of the front vehicle of the vehicle is converted into a coordinate system of the constant-curvature running path of the vehicle, the relative motion information of the front vehicle relative to the constant-curvature running path of the vehicle is obtained, and therefore the nearest vehicle ahead of the vehicle is determined based on the running speed of the vehicle and the relative motion information of the front vehicle relative to the constant-curvature running path of the vehicle, so that the longitudinal speed of the vehicle is controlled. Therefore, the invention can be seen in that the motion information of the front vehicle of the vehicle is converted into the coordinate system of the constant-curvature running path of the vehicle, so that the nearest front vehicle of the vehicle is determined under the condition that the lane line information is invalid, and the scheme is simultaneously suitable for the condition that the vehicle is in a straight line and a curve track.
Referring to fig. 1, an embodiment of the present invention discloses a flowchart of a method for determining a vehicle nearest to a leading vehicle, the method including the steps of:
step S101, acquiring motion information of the vehicle, recording the motion information as first motion information, motion information of a vehicle ahead of the vehicle, recording the motion information as second motion information and lane line information;
it should be noted that the "first" of the "first motion information" and the "second" of the "second motion information" in this step are merely used to distinguish the motion information of the host vehicle from the motion information of the preceding vehicle, and do not require or suggest any such actual relationship or order between the motion information of the host vehicle and the motion information of the preceding vehicle.
Specifically, the first motion information of the host vehicle includes: travel speed and yaw rate. In practical applications, the speed sensor mounted on the vehicle may be used to obtain the traveling speed of the vehicle, and the angular velocity sensor mounted on the vehicle may be used to obtain the yaw rate of the vehicle.
The second operation information of the preceding vehicle includes: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the host vehicle.
The lane line information includes: lane line recognition, lane line position, heading angle, curvature, and curvature change rate.
In practical application, the camera and the radar mounted on the vehicle can be used to obtain the motion information and lane line information of the vehicle ahead, which may be referred to a mature scheme in the prior art, and are not described herein again.
Step S102, judging whether the lane line information is valid, if not, executing step S103;
it should be noted that whether the lane line information is valid or not means: whether the lane line information exists, is complete and accurate or not, and when the lane line information exists, is complete and accurate, the lane line information is judged to be effective; on the contrary, when the lane line information satisfies: and when any one or more of the three conditions of non-existence, incompleteness and inaccuracy exist, judging that the lane line information is invalid.
Step S103, obtaining the curvature radius of the vehicle fixed-curvature running path based on the first motion information;
in practical applications, the vehicle travel path may be regarded as a constant-curvature travel path, and therefore, the curvature radius of the constant-curvature travel path of the vehicle may be estimated based on the motion information of the vehicle.
The curvature radius R of the vehicle constant-curvature running path is calculated according to the following formula (1), wherein the formula (1) is as follows:
R＝VehSpd/Yawrate(1)；
where VehSpd is the traveling speed of the vehicle and Yawrate is the yaw rate of the vehicle.
Step S104, based on the curvature radius, converting the second motion information into a coordinate system of the vehicle constant-curvature running path to obtain relative motion information of the front vehicle relative to the vehicle constant-curvature running path;
the relative movement information of the preceding vehicle with respect to the constant-curvature travel path of the own vehicle includes: longitudinal curve distance, transverse straight line distance, and longitudinal velocity.
Specifically, referring to fig. 2, an exemplary distance conversion diagram of a leading vehicle when the vehicle is in a curved track is disclosed, where 1 in fig. 2 is the vehicle, 2 is the leading vehicle, a black bold curve is a vehicle constant curvature driving path estimated from the driving speed VehSpd of the vehicle and the yaw rate of the vehicle, and a formula for calculating the curvature radius R of the vehicle constant curvature driving path refers to formula (1).
Suppose that the longitudinal distance between the front vehicle 2 and the host vehicle 1 is x, the lateral distance is y, and the longitudinal relative velocity is vxTransverse relative velocity vy；
The motion information of the front vehicle relative to the vehicle constant-curvature running path comprises the following components: longitudinal curve distance xalignThe transverse straight-line distance is yalignAnd a longitudinal velocity vx_align。
According to the formula (2), the transverse position deviation y between the vehicle and the front vehicle in the constant-curvature running path of the vehicle is calculatedoffsetEquation (2) is as follows:
yoffser＝abs(R-y) (2)；
where abs (R-y) is a function of the absolute value of the difference between (R-y).
Calculating an included angle theta between a connecting line of the center of the front vehicle and the center of the circle of the constant-curvature running path of the vehicle and the horizontal direction according to a formula (3), wherein the formula (3) is as follows:
θ＝arctan(x/yoffset)(3)；
according to the formula (4), calculating the longitudinal curve distance x of the front vehicle relative to the constant-curvature running path of the vehiclealignEquation (4) is as follows:
xalign＝abs(R)×θ (4)；
where abs (R) is a function of the absolute value of R.
According to the formula (5), the transverse straight-line distance y of the front vehicle relative to the constant-curvature running path of the vehicle is calculatedalignEquation (5) is as follows:
Figure BDA0001930801290000091
wherein sign (R) is a sign function of the radius of curvature R.
According to the formula (6), the longitudinal speed v of the front vehicle relative to the constant-curvature running path of the vehicle is calculatedx_alignEquation (6) is as follows:
vx_align＝vx·cosθ+vy·sinθ·sign(R) (6)。
it should be noted that although fig. 2 shows a schematic diagram of distance conversion of a preceding vehicle in a case where the host vehicle is in a curved track, the diagram shown in fig. 2 is not only applicable to a case where the host vehicle is in a curved track, but also applicable to a case where the host vehicle is in a straight track, and when the host vehicle is in a straight track, the yaw rate of the host vehicle is an extremely small value, and the curvature radius R calculated according to the formula (1) is an extremely large value, so that the black bold curve in fig. 2 is approximated to a straight line.
Step S105, the nearest vehicle in front of the vehicle is determined based on the running speed of the vehicle and the relative motion information of the preceding vehicle relative to the constant-curvature running path of the vehicle.
In practical applications, the nearest vehicle ahead of the vehicle may be determined by using the longitudinal curve distance between the vehicle ahead of the vehicle and the vehicle; the nearest vehicle ahead of the host vehicle may be determined by using the longitudinal collision time of the vehicle ahead of the host vehicle with respect to the constant-curvature travel path of the host vehicle.
As can be seen from the above, in the method for determining the nearest leading vehicle disclosed in the present invention, when it is determined that the acquired lane line information is invalid, the motion information of the leading vehicle of the own vehicle is converted into the coordinate system of the constant-curvature travel path of the own vehicle, the relative motion information of the leading vehicle with respect to the constant-curvature travel path of the own vehicle is obtained, and the nearest leading vehicle of the own vehicle is determined based on the travel speed of the own vehicle and the relative motion information of the leading vehicle with respect to the constant-curvature travel path of the own vehicle, so as to control the longitudinal speed of the own vehicle. Therefore, the invention can be seen in that the motion information of the front vehicle of the vehicle is converted into the coordinate system of the constant-curvature running path of the vehicle, so that the nearest front vehicle of the vehicle is determined under the condition that the lane line information is invalid, and the scheme is simultaneously suitable for the condition that the vehicle is in a straight line and a curve track.
Based on the above discussion, in practical applications, the nearest on-path front vehicle of the host vehicle can be determined by using the longitudinal curve distance between the front vehicle of the host vehicle and the host vehicle; the nearest vehicle ahead of the host vehicle may also be determined by using the longitudinal collision time of the vehicle ahead of the host vehicle with respect to the constant-curvature running path of the host vehicle, and therefore, step S105 may specifically include:
(1) when the running speed of the vehicle is in the preset speed interval, the maximum speed value in the preset speed interval is a speed threshold value, the longitudinal curve distance of the front vehicle of the vehicle is compared, and the front vehicle with the shortest longitudinal curve distance is determined as the nearest front vehicle in the path of the vehicle.
In this embodiment, the predetermined speed interval is determined according to the actual requirement, such as [0, 10] m/s.
As can be seen from step S104, in the present invention, since the relative travel information of all the preceding vehicles with respect to the vehicle constant-curvature travel path is obtained by converting the second travel information of all the preceding vehicles of the vehicle into the coordinate system of the vehicle constant-curvature travel path, the longitudinal curve distances of the preceding vehicles of the vehicle are compared to determine the longitudinal threat degree of each preceding vehicle to the vehicle, and when the longitudinal curve distance between a certain preceding vehicle and the vehicle is shortest, it indicates that the threat made by the preceding vehicle to the vehicle is the greatest, in this case, the preceding vehicle with the shortest longitudinal curve distance is determined as the nearest preceding vehicle to the vehicle. In practical application, the longitudinal speed of the vehicle can be controlled, so that the vehicle and the nearest vehicle in front of the vehicle keep a preset safe distance.
When the running speed of the vehicle is in the preset speed interval and only one vehicle is in front of the vehicle, the vehicle is determined as the nearest vehicle in front of the vehicle.
(2) When the running speed of the vehicle is greater than the speed threshold value, calculating the longitudinal collision time ttc of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle according to the formula (7)xEquation (7) is as follows:
ttcx＝xalign/vx_align
(7)；
in the formula, xalignThe longitudinal curve distance, v, of the leading vehicle relative to the path of constant curvature of the vehiclex_alignThe longitudinal speed of the front vehicle relative to the constant-curvature running path of the self vehicle.
And comparing the sizes of the longitudinal collision time obtained by calculation, and determining the front vehicle with the shortest longitudinal collision time as the nearest front vehicle in the path of the vehicle.
When the running speed of the vehicle is greater than the speed threshold value and only one vehicle exists in front of the vehicle, the vehicle is determined as the nearest vehicle in front of the vehicle.
When the traveling speed of the host vehicle is high, in order to improve the traveling safety, the nearest vehicle ahead of the host vehicle is determined by using the longitudinal collision time of the host vehicle with respect to the constant-curvature traveling path of the host vehicle, instead of determining the nearest vehicle ahead of the host vehicle simply based on the longitudinal curve distance between the host vehicle ahead of the host vehicle and the host vehicle.
The value of the speed threshold is determined according to actual needs, for example, 10m/s, and the invention is not limited herein.
In summary, the present invention adopts different schemes for determining the nearest vehicle ahead of the own vehicle for the own vehicles in different speed intervals, and when the speed of the own vehicle is slow, the nearest vehicle ahead of the own vehicle can be determined simply by using the longitudinal curve distance between the own vehicle ahead and the own vehicle; on the contrary, when the speed of the vehicle is higher, in order to improve the driving safety, the invention utilizes the longitudinal collision time of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle to determine the nearest front vehicle of the vehicle, both the two schemes are suitable for the situation that the vehicle is in a straight line and a curve track, compared with the traditional scheme that the nearest front vehicle of the vehicle is determined simply according to the longitudinal distance between the vehicle and the front vehicle, the invention greatly improves the reliability of determining the nearest front vehicle, thereby providing a basis for improving the control precision of the vehicle and reducing the collision risk between the vehicles.
In the above-described embodiment, when the lane line information is valid, that is, when the lane line information is present, complete, and accurate, the nearest leading vehicle of the host vehicle may be determined based on the lane line information.
Therefore, to further optimize the above embodiment, when the step S102 determines that the lane line information is invalid, the vehicle selection method may further include the steps of:
and step S106, determining the nearest vehicle ahead of the vehicle based on the lane line information.
Specifically, when the vehicle is a straight-line driving path, under the condition that there is lane line information, the nearest vehicle ahead of the vehicle in the path may be determined simply according to the longitudinal distance between the vehicle and the vehicle ahead, which may be referred to in the existing mature scheme, and is not described herein again.
When the host vehicle is a curved track traveling path, the candidate leading vehicles can be determined by using the position, the direction angle, the curvature change rate and the lane line recognition degree in the lane line information, and whether the lateral straight-line distance of the leading vehicle relative to the host vehicle is located in the middle of the lateral distances of two boundaries of the lane lines, and then the nearest leading vehicle of the host vehicle can be determined from the candidate leading vehicles by adopting the schemes in the steps S103 to S105 according to the second motion information of the candidate leading vehicles and the first motion information of the host vehicle.
It can be understood that, during the driving process of the vehicle, some disturbing vehicles cannot be avoided on the driving path, and the disturbing vehicles can repeatedly cut into the detection range of the sensor of the vehicle, so that the repeated vehicles are mistakenly cut into the vehicle which is the closest vehicle ahead, and the closest vehicle ahead is frequently switched, so that the vehicle is frequently braked or decelerated, and the driving comfort is reduced.
Based on this, the present invention determines the nearest vehicle ahead of the own vehicle based on the embodiment shown in fig. 1, and then further determines the driving stability of the nearest vehicle ahead.
Therefore, the step S105 may specifically include:
according to the running speed and the relative motion information of the vehicle, increasing the characteristic value of the front vehicle with the shortest longitudinal collision time by a preset amplitude value, and simultaneously reducing the characteristic value of the front vehicle with the shortest non-longitudinal collision time by the preset amplitude value;
and selecting the front vehicle with the maximum characteristic value as the nearest front vehicle in the path of the vehicle.
The process of selecting the leading vehicle with the largest characteristic value as the nearest leading vehicle in the path of the vehicle may include:
counting the number of times that each preceding vehicle becomes the nearest preceding vehicle in the vehicle in each adjacent period after the preset number of adjacent periods are ended, and rejecting the preceding vehicles of which the occurrence number is lower than the preset number of times and the characteristic values after the preset number of adjacent periods are ended are not the maximum value among the characteristic values of each preceding vehicle;
and selecting the front vehicle with the maximum characteristic value after the preset number of adjacent cycles are ended as the nearest front vehicle in the path of the vehicle.
Wherein adjacent periods refer to two adjacent sampling periods.
For example, it is assumed that the initial value of the feature value of each nearest vehicle ahead is 0, the preset amplitude is 2, and the preset number of adjacent cycles is 5.
When a certain preceding vehicle of the host vehicle is determined as the nearest preceding vehicle of the host vehicle in the first sampling period, the feature value of the nearest preceding vehicle is added by 2.
In a second sampling period, adopting the embodiment shown in fig. 1, when the nearest vehicle ahead of the vehicle is determined again, judging whether the nearest vehicle ahead of the vehicle determined in the second sampling period and the nearest vehicle ahead of the vehicle determined in the first sampling period are the same vehicle ahead, if so, adding 2 again to the feature value of the nearest vehicle ahead of the vehicle determined in the first sampling period; and if not, adding 2 to the characteristic value of the vehicle in front of the nearest path determined by the second sampling period, and subtracting 2 from the characteristic value of the vehicle in front of the nearest path determined by the first sampling period.
Since adjacent periods refer to two adjacent sampling periods, the first sampling period and the second sampling period in the present embodiment may be referred to as one adjacent period.
This is repeated until the number of adjacent cycles reaches 5, and the preceding vehicle having the largest feature value is set as the nearest preceding vehicle of the own vehicle, so that the own vehicle performs longitudinal vehicle speed control based on the target nearest preceding vehicle.
Therefore, the invention effectively avoids the situation that the vehicle is frequently braked or decelerated before the vehicle is in the path due to the frequent switching of the vehicle in the near distance caused by the existence of the disturbance vehicle in the driving process of the vehicle, thereby improving the driving comfort level.
Corresponding to the embodiment of the method, the invention also discloses a system for determining the nearest vehicle ahead of the vehicle.
Referring to fig. 3, a schematic structural diagram of a system for determining a nearest vehicle ahead of a route according to an embodiment of the present invention is disclosed, and the system includes:
an obtaining unit 201, configured to obtain motion information of a host vehicle, and record the motion information as first motion information, motion information of a vehicle ahead of the host vehicle, and record the motion information as second motion information, and lane line information;
it should be noted that the "first" of the "first motion information" and the "second" of the "second motion information" in the present embodiment are merely used to distinguish the motion information of the host vehicle from the motion information of the preceding vehicle, and do not require or suggest any such actual relationship or order between the motion information of the host vehicle and the motion information of the preceding vehicle.
Specifically, the first motion information of the host vehicle includes: travel speed and yaw rate. In practical applications, the speed sensor mounted on the vehicle may be used to obtain the traveling speed of the vehicle, and the angular velocity sensor mounted on the vehicle may be used to obtain the yaw rate of the vehicle.
The second operation information of the preceding vehicle includes: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the host vehicle.
The lane line information includes: lane line recognition, lane line position, heading angle, curvature, and curvature change rate.
In practical application, the camera and the radar mounted on the vehicle can be used to obtain the motion information and lane line information of the vehicle ahead, which may be referred to a mature scheme in the prior art, and are not described herein again.
A first judging unit 202, configured to judge whether the lane line information is valid;
it should be noted that whether the lane line information is valid or not means: whether the lane line information exists, is complete and accurate or not, and when the lane line information exists, is complete and accurate, the lane line information is judged to be effective; on the contrary, when the lane line information satisfies: and when any one or more of the three conditions of non-existence, incompleteness and inaccuracy exist, judging that the lane line information is invalid.
A curvature radius obtaining unit 203 for obtaining a curvature radius of the own vehicle fixed-curvature traveling path based on the first motion information in a case where the first judging unit 202 judges no;
in practical applications, the vehicle travel path may be regarded as a constant-curvature travel path, and therefore, the curvature radius of the constant-curvature travel path of the vehicle may be estimated based on the motion information of the vehicle.
The curvature radius R of the vehicle constant-curvature running path is calculated according to the following formula (1), wherein the formula (1) is as follows:
R＝VehSpd/Yawrate (1)；
where VehSpd is the traveling speed of the vehicle and Yawrate is the yaw rate of the vehicle.
A relative motion information obtaining unit 204, configured to convert the second motion information into a coordinate system of the vehicle constant-curvature traveling path based on the curvature radius, and obtain relative motion information of the leading vehicle relative to the vehicle constant-curvature traveling path;
the relative motion information includes: longitudinal curve distance, transverse straight line distance, and longitudinal velocity.
The relative movement information of the preceding vehicle with respect to the constant-curvature travel path of the own vehicle includes: longitudinal curve distance, transverse straight line distance, and longitudinal velocity.
Specifically, referring to fig. 2, an exemplary distance conversion diagram of a leading vehicle when the vehicle is in a curved track is disclosed, where 1 in fig. 2 is the vehicle, 2 is the leading vehicle, a black bold curve is a vehicle constant curvature driving path estimated from the driving speed VehSpd of the vehicle and the yaw rate of the vehicle, and a formula for calculating the curvature radius R of the vehicle constant curvature driving path refers to formula (1).
Suppose that the longitudinal distance between the front vehicle 2 and the host vehicle 1 is x, the lateral distance is y, and the longitudinal relative velocity is vxTransverse relative velocity vy；
The motion information of the front vehicle relative to the vehicle constant-curvature running path comprises the following components: longitudinal curve distance xalignThe transverse straight-line distance is yalignAnd a longitudinal velocity vx_align。
According to the formula (2), the transverse position deviation y between the vehicle and the front vehicle in the constant-curvature running path of the vehicle is calculatedoffsetEquation (2) is as follows:
yoffset＝abs(R-y) (2)；
where abs (R-y) is a function of the absolute value of the difference between (R-y).
Calculating an included angle theta between a connecting line of the center of the front vehicle and the center of the circle of the constant-curvature running path of the vehicle and the horizontal direction according to a formula (3), wherein the formula (3) is as follows:
θ＝arctan(x/yoffset) (3)；
according to the formula (4), calculating the longitudinal curve distance x of the front vehicle relative to the constant-curvature running path of the vehiclealignEquation (4) is as follows:
xalign＝abs(R)×θ (4)；
where abs (R) is a function of the absolute value of R.
According to the formula (5), the transverse straight-line distance y of the front vehicle relative to the constant-curvature running path of the vehicle is calculatedalignEquation (5) is as follows:
Figure BDA0001930801290000161
wherein sign (R) is a sign function of the radius of curvature R.
According to the formula (6), the longitudinal speed v of the front vehicle relative to the constant-curvature running path of the vehicle is calculatedx_alignEquation (6) is as follows:
vx_align＝vx·cosθ+vy·sinθ·sign(R) (6)。
it should be noted that although fig. 2 shows a schematic diagram of distance conversion of a preceding vehicle in a case where the host vehicle is in a curved track, the diagram shown in fig. 2 is not only applicable to a case where the host vehicle is in a curved track, but also applicable to a case where the host vehicle is in a straight track, and when the host vehicle is in a straight track, the yaw rate of the host vehicle is an extremely small value, and the curvature radius R calculated according to the formula (1) is an extremely large value, so that the black bold curve in fig. 2 is a straight line.
The first nearest leading vehicle determination unit 205 is configured to determine a nearest leading vehicle of the host vehicle based on the traveling speed and the relative motion information of the host vehicle.
In practical applications, the nearest vehicle ahead of the vehicle may be determined by using the longitudinal curve distance between the vehicle ahead of the vehicle and the vehicle; the nearest vehicle ahead of the host vehicle may be determined by using the longitudinal collision time of the vehicle ahead of the host vehicle with respect to the constant-curvature travel path of the host vehicle.
As can be seen from the above, in the system for identifying a nearest leading vehicle according to the present invention, when it is determined that the acquired lane line information is invalid, the motion information of the leading vehicle of the host vehicle is converted into the coordinate system of the constant-curvature travel path of the host vehicle, and the relative motion information of the leading vehicle with respect to the constant-curvature travel path of the host vehicle is obtained, so that the nearest leading vehicle of the host vehicle is identified based on the travel speed of the host vehicle and the relative motion information of the leading vehicle with respect to the constant-curvature travel path of the host vehicle, and the longitudinal speed of the host vehicle is controlled. Therefore, the invention can be seen in that the motion information of the front vehicle of the vehicle is converted into the coordinate system of the constant-curvature running path of the vehicle, so that the nearest front vehicle of the vehicle is determined under the condition that the lane line information is invalid, and the scheme is simultaneously suitable for the condition that the vehicle is in a straight line and a curve track.
Based on the above discussion, in practical applications, the nearest on-path front vehicle of the host vehicle can be determined by using the longitudinal curve distance between the front vehicle of the host vehicle and the host vehicle; the longitudinal collision time of the vehicle ahead of the host vehicle with respect to the vehicle constant-curvature traveling path may also be used to determine the nearest ahead vehicle of the host vehicle, and the first nearest ahead vehicle determining unit 205 may be specifically configured to: when the running speed of the vehicle is in a preset speed interval, comparing the longitudinal curve distance of the front vehicle relative to the constant-curvature running path of the vehicle, and determining the front vehicle with the shortest longitudinal curve distance as the nearest front vehicle of the vehicle;
and the maximum speed value in the preset speed interval is a speed threshold value. The preset speed interval depends on the actual requirement, such as [0, 10] m/s.
When the running speed of the vehicle is in the preset speed interval and only one vehicle is in front of the vehicle, the vehicle is determined as the nearest vehicle in front of the vehicle.
The first nearest leading vehicle determining unit 205 may further be specifically configured to:
when the running speed of the vehicle is larger than the speed threshold value, calculating the longitudinal collision time of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle according to the formula (7), wherein the formula (7) is as follows:
ttcx＝xalign/vx_align
(7)；
in the formula, ttcxAs longitudinal collision time, xalignThe longitudinal curve distance, v, of the leading vehicle relative to the path of constant curvature of the vehiclex_alignThe longitudinal speed of the front vehicle relative to the constant-curvature running path of the vehicle is obtained;
and comparing the sizes of the longitudinal collision time obtained by calculation, and determining the front vehicle with the shortest longitudinal collision time as the nearest front vehicle in the path of the vehicle.
When the running speed of the vehicle is greater than the speed threshold value and only one vehicle exists in front of the vehicle, the vehicle is determined as the nearest vehicle in front of the vehicle.
When the traveling speed of the host vehicle is high, in order to improve the traveling safety, the nearest vehicle ahead of the host vehicle is determined by using the longitudinal collision time of the host vehicle with respect to the constant-curvature traveling path of the host vehicle, instead of determining the nearest vehicle ahead of the host vehicle simply based on the longitudinal curve distance between the host vehicle ahead of the host vehicle and the host vehicle.
The value of the speed threshold is determined according to actual needs, for example, 10m/s, and the invention is not limited herein.
In summary, the present invention adopts different schemes for determining the nearest vehicle ahead of the own vehicle for the own vehicles in different speed intervals, and when the speed of the own vehicle is slow, the nearest vehicle ahead of the own vehicle can be determined simply by using the longitudinal curve distance between the own vehicle ahead and the own vehicle; on the contrary, when the speed of the vehicle is higher, in order to improve the driving safety, the invention utilizes the longitudinal collision time of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle to determine the nearest front vehicle of the vehicle, both the two schemes are suitable for the situation that the vehicle is in a straight line and a curve track, compared with the traditional scheme that the nearest front vehicle of the vehicle is determined simply according to the longitudinal distance between the vehicle and the front vehicle, the invention greatly improves the reliability of determining the nearest front vehicle, thereby providing a basis for improving the control precision of the vehicle and reducing the collision risk between the vehicles.
In the above-described embodiment, when the lane line information is valid, that is, when the lane line information is present, complete, and accurate, the nearest leading vehicle of the host vehicle may be determined based on the lane line information.
Therefore, to further optimize the above embodiment, the system for determining the nearest vehicle ahead of the route may further include:
a second nearest leading vehicle determination unit 206 configured to determine a nearest leading vehicle of the own vehicle based on the lane line information when the first judgment unit 202 judges no.
Specifically, when the vehicle is a straight-line driving path, under the condition that there is lane line information, the nearest vehicle ahead of the vehicle in the path may be determined simply according to the longitudinal distance between the vehicle and the vehicle ahead, which may be referred to in the existing mature scheme, and is not described herein again.
When the host vehicle is a curved trajectory travel path, candidate leading vehicles may be determined using the position, the direction angle, the curvature change rate, and the lane line recognition degree in the lane line information, and whether the lateral straight-line distance of the leading vehicle with respect to the host vehicle is located in the middle of the lateral distances of the two boundaries of the lane lines, and then the nearest leading vehicle of the host vehicle may be determined from the candidate leading vehicles using the schemes in the curvature radius acquisition unit 203, the relative motion information acquisition unit 204, and the first nearest leading vehicle determination unit 205, based on the second motion information of the candidate leading vehicles and the first motion information of the host vehicle.
It can be understood that, during the driving process of the vehicle, some disturbing vehicles cannot be avoided on the driving path, and the disturbing vehicles can repeatedly cut into the detection range of the sensor of the vehicle, so that the vehicle mistakenly cuts into the vehicle as the vehicle in front of the nearest vehicle, thereby causing frequent switching of the vehicle in front of the nearest vehicle, frequently braking or frequently decelerating the vehicle, and further reducing the driving comfort.
Based on this, the present invention determines the nearest vehicle ahead of the own vehicle based on the embodiment shown in fig. 3, and then further determines the driving stability of the nearest vehicle ahead.
Therefore, the first nearest leading vehicle determination unit 205 may include:
the numerical value adjusting subunit is used for increasing the characteristic value of the front vehicle with the shortest longitudinal collision time by a preset amplitude value according to the running speed and the relative motion information of the vehicle, and simultaneously reducing the characteristic value of the front vehicle with the shortest non-longitudinal collision time by the preset amplitude value;
and the selecting subunit is used for selecting the front vehicle with the largest characteristic value as the nearest front vehicle in the path of the vehicle.
Wherein the selecting subunit is specifically configured to:
counting the number of times that each preceding vehicle becomes the nearest preceding vehicle in the vehicle in each adjacent period after the preset number of adjacent periods are ended, and rejecting the preceding vehicles of which the occurrence number is lower than the preset number of times and the characteristic values after the preset number of adjacent periods are ended are not the maximum value among the characteristic values of each preceding vehicle;
and selecting the front vehicle with the maximum characteristic value after the preset number of adjacent cycles are ended as the nearest front vehicle in the path of the vehicle.
Wherein adjacent periods refer to two adjacent sampling periods.
Therefore, the invention effectively avoids the situation that the vehicle is frequently braked or decelerated before the vehicle is in the path due to the frequent switching of the vehicle in the near distance caused by the existence of the disturbance vehicle in the driving process of the vehicle, thereby improving the driving comfort level.
It should be noted that, for the specific working principle of each component in the system embodiment, please refer to the corresponding part of the method embodiment, which is not described herein again.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. A method of determining a nearest in-path vehicle, comprising:
acquiring motion information of a vehicle, and recording the motion information as first motion information, wherein the first motion information comprises: the method comprises the following steps of obtaining motion information of a front vehicle of the vehicle according to a running speed and a yaw rate, and recording the motion information as second motion information, wherein the second motion information comprises: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the vehicle, and acquiring lane line information;
judging whether the lane line information is valid or not;
if not, obtaining the curvature radius of the vehicle running path with the fixed curvature based on the first motion information;
based on the curvature radius, converting the second motion information into a coordinate system of the vehicle constant-curvature running path to obtain relative motion information of the front vehicle relative to the vehicle constant-curvature running path, wherein the relative motion information comprises: longitudinal curve distance, transverse straight line distance and longitudinal speed;
determining a nearest vehicle ahead of the vehicle based on the traveling speed and the relative motion information of the vehicle, specifically comprising: according to the running speed and the relative motion information of the vehicle, increasing the characteristic value of the front vehicle with the shortest longitudinal collision time by a preset amplitude value, and simultaneously reducing the characteristic value of the front vehicle with the shortest non-longitudinal collision time by the preset amplitude value; selecting the front vehicle with the largest characteristic value as the nearest front vehicle on the path of the vehicle;
wherein the selecting the leading vehicle with the largest characteristic value as the nearest leading vehicle on the path of the vehicle comprises:
counting the number of times that each preceding vehicle becomes the nearest preceding vehicle in the adjacent period after the adjacent period of the preset number is finished, and rejecting the preceding vehicle of which the occurrence number is lower than the preset number and the characteristic value after the adjacent period of the preset number is finished is not the maximum value in the characteristic values of each preceding vehicle;
and selecting the front vehicle with the maximum characteristic value after the preset number of adjacent cycles are ended as the nearest front vehicle in the path of the vehicle.
2. The method according to claim 1, wherein the process of obtaining the curvature radius R of the vehicle path with constant curvature based on the first motion information is:
R＝VehSpd/Yawrate；
wherein VehSpd is the driving speed and Yawrate is the yaw rate.
3. The method according to claim 2, wherein converting the second motion information into a coordinate system of the vehicle constant-curvature traveling path based on the curvature radius to obtain the relative motion information of the leading vehicle with respect to the vehicle constant-curvature traveling path comprises:
calculating to obtain the transverse position deviation y between the vehicle and the front vehicle in the constant-curvature running path of the vehicleoffsetThe process is as follows:
yoffset＝abs(R-y)；
wherein abs (R-y) is a function of the absolute value of the difference between (R-y), and y is the lateral distance between the leading vehicle and the host vehicle;
calculating to obtain an included angle theta between a connecting line of the center of the front vehicle and the circle center of the constant-curvature running path of the vehicle and the horizontal direction, wherein the process is as follows:
θ＝arctan(x/yoffset)；
wherein x is the longitudinal distance between the front vehicle and the vehicle;
calculating to obtain the longitudinal curve distance x of the front vehicle relative to the constant-curvature running path of the vehiclealignThe process is as follows:
xalign＝abs(R)×θ；
wherein abs (R) is a function of the absolute value of R;
calculating to obtain the transverse straight-line distance y of the front vehicle relative to the constant-curvature running path of the vehiclealignThe process is as follows:
Figure FDA0002587193890000021
wherein sign (R) is a sign function of the radius of curvature R;
calculating to obtain the longitudinal speed v of the front vehicle relative to the constant-curvature running path of the self vehiclex_alignThe process is as follows:
vx_align＝vx·cosθ+vy·sinθ·sign(R)；
wherein v isxIs the longitudinal relative speed, v, of the leading vehicle and the own vehicleyThe transverse relative speed of the front vehicle and the vehicle is obtained.
4. The method of claim 1, wherein the calculating of the longitudinal collision time comprises:
when the running speed of the vehicle is greater than a speed threshold value, calculating the longitudinal collision time of the front vehicle of the vehicle relative to the constant-curvature running path of the vehicle, wherein the process is as follows:
ttcx＝xalign/vx_align；
wherein ttcxAs the longitudinal collision time, xalignFor the longitudinal curve distance, v, of the leading vehicle relative to the path of constant curvature of the vehiclex_alignThe longitudinal speed of the front vehicle relative to the vehicle constant-curvature running path is obtained.
5. A system for determining a nearest in-path vehicle, comprising:
an obtaining unit, configured to obtain motion information of a host vehicle, and record the motion information as first motion information, where the first motion information includes: the method comprises the following steps of obtaining motion information of a front vehicle of the vehicle according to a running speed and a yaw rate, and recording the motion information as second motion information, wherein the second motion information comprises: the longitudinal distance, the transverse distance and the longitudinal relative speed of the front vehicle and the vehicle, and acquiring lane line information;
the first judging unit is used for judging whether the lane line information is valid or not;
a curvature radius obtaining unit configured to obtain a curvature radius of the vehicle constant-curvature traveling path based on the first motion information when the first determination unit determines that the vehicle is not traveling;
a relative motion information obtaining unit, configured to convert the second motion information into a coordinate system of the vehicle constant-curvature traveling path based on the curvature radius, and obtain relative motion information of the leading vehicle relative to the vehicle constant-curvature traveling path, where the relative motion information includes: longitudinal curve distance, transverse straight line distance and longitudinal speed;
a first nearest vehicle ahead determination unit configured to determine a nearest vehicle ahead of the host vehicle based on the travel speed of the host vehicle and the relative motion information;
wherein the first nearest leading vehicle determining unit includes:
the numerical value adjusting subunit is used for increasing the characteristic value of the front vehicle with the shortest longitudinal collision time by a preset amplitude value according to the running speed and the relative motion information of the vehicle, and simultaneously reducing the characteristic value of the front vehicle with the shortest non-longitudinal collision time by the preset amplitude value;
the selecting subunit is used for selecting the front vehicle with the largest characteristic value as the nearest front vehicle in the path of the vehicle;
the selecting subunit is specifically configured to:
counting the number of times that each preceding vehicle becomes the nearest preceding vehicle in the adjacent period after the adjacent period of the preset number is finished, and rejecting the preceding vehicle of which the occurrence number is lower than the preset number and the characteristic value after the adjacent period of the preset number is finished is not the maximum value in the characteristic values of each preceding vehicle;
and selecting the front vehicle with the maximum characteristic value after the preset number of adjacent cycles are ended as the nearest front vehicle in the path of the vehicle.
CN201811639283.9A 2018-12-29 2018-12-29 Method and system for determining nearest on-path front vehicle Active CN109693669B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811639283.9A CN109693669B (en) 2018-12-29 2018-12-29 Method and system for determining nearest on-path front vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811639283.9A CN109693669B (en) 2018-12-29 2018-12-29 Method and system for determining nearest on-path front vehicle

Publications (2)

Publication Number Publication Date
CN109693669A CN109693669A (en) 2019-04-30
CN109693669B true CN109693669B (en) 2021-02-19

Family

ID=66233104

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811639283.9A Active CN109693669B (en) 2018-12-29 2018-12-29 Method and system for determining nearest on-path front vehicle

Country Status (1)

Country Link
CN (1) CN109693669B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111319623B (en) * 2020-03-18 2021-10-26 东软睿驰汽车技术（上海）有限公司 Vehicle screening method and device based on adaptive cruise control
CN111591296B (en) * 2020-04-29 2021-07-02 惠州市德赛西威智能交通技术研究院有限公司 Vehicle same-lane position judgment method based on V2X technology
CN112026773B (en) * 2020-08-27 2021-09-03 重庆长安汽车股份有限公司 Method for planning driving acceleration of automatic driving curve
CN113511081B (en) * 2021-06-03 2023-10-10 北京车和家信息技术有限公司 Control method and device for self-adaptive energy recovery of electric automobile
CN115567875A (en) * 2021-06-30 2023-01-03 中兴通讯股份有限公司 Method for judging same lane, electronic device and computer readable storage medium

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005020182A1 (en) * 2003-08-20 2005-03-03 Hitachi, Ltd. Device and method for selecting preceding vehicle
US8483944B2 (en) * 2008-12-24 2013-07-09 Toyota Jidosha Kabushiki Kaisha Collision determination device
CN104101878B (en) * 2014-06-23 2017-02-15 北京智行者科技有限公司 Vehicle front target recognition system and recognition method
JP6507525B2 (en) * 2014-08-22 2019-05-08 株式会社アドヴィックス Vehicle control device
CN106601029A (en) * 2017-02-17 2017-04-26 重庆长安汽车股份有限公司 Forward collision early-warning method and system based on curve self-adaption
CN108569289A (en) * 2017-05-19 2018-09-25 浙江工业职业技术学院 A kind of trailer-mounted radar and its approach detection and target-recognition method

Also Published As

Publication number Publication date
CN109693669A (en) 2019-04-30

Similar Documents

Publication Publication Date Title
CN109720345B (en) Cut-in vehicle monitoring method and system
CN109693669B (en) Method and system for determining nearest on-path front vehicle
CN109572672B (en) Vehicle driving assistance device
US10077050B2 (en) Automated driving system for evaluating lane cut-out and method of using the same
US9896095B2 (en) Collision avoidance support device
EP3613647B1 (en) Automatic parking control device
US9260113B2 (en) Method and device for generating a control parameter for a distance control system of a vehicle
US11021155B2 (en) Vehicle control apparatus and vehicle control method
US10864913B2 (en) Vehicle driving support apparatus
CN110723141B (en) Vehicle active collision avoidance system and collision avoidance mode switching method thereof
US20150239472A1 (en) Vehicle-installed obstacle detection apparatus having function for judging motion condition of detected object
US20130158830A1 (en) Leading Vehicle Detecting Apparatus And Inter-Vehicular Control Apparatus Using Leading Vehicle Detecting Apparatus
US20150375744A1 (en) Cruise controller
CN102653272A (en) Vehicle driving support apparatus
US11628835B2 (en) Vehicle control system
JP7081423B2 (en) Information processing system
CN103946906A (en) Vehicle identification device
US11072334B2 (en) Vehicle control system
CN104943689A (en) Control method for active automobile anti-collision system
US11054832B2 (en) Vehicle control device for setting vehicle offset spacing
US20210163039A1 (en) Vehicle control system and vehicle control method
JP6497329B2 (en) Vehicle travel control device
JP2006188129A (en) Collision load reducing vehicle system
JP2019130997A (en) Vehicle controlling apparatus
JP7201310B2 (en) vehicle control system

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
CB02 Change of applicant information

Address after: 4 / F, building 1, No.14 Jiuxianqiao Road, Chaoyang District, Beijing 100020

Applicant after: Beijing Jingwei Hirain Technologies Co.,Inc.

Address before: 8 / F, block B, No. 11, Anxiang Beili, Chaoyang District, Beijing 100101

Applicant before: Beijing Jingwei HiRain Technologies Co.,Ltd.

CB02 Change of applicant information
GR01 Patent grant
GR01 Patent grant