CN107274721B - Multi-vehicle cooperative positioning method in intelligent transportation system - Google Patents
Multi-vehicle cooperative positioning method in intelligent transportation system Download PDFInfo
- Publication number
- CN107274721B CN107274721B CN201710423028.XA CN201710423028A CN107274721B CN 107274721 B CN107274721 B CN 107274721B CN 201710423028 A CN201710423028 A CN 201710423028A CN 107274721 B CN107274721 B CN 107274721B
- Authority
- CN
- China
- Prior art keywords
- target vehicle
- vehicle
- value
- observation
- adjacent
- 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.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000001914 filtration Methods 0.000 claims abstract description 23
- 238000005259 measurement Methods 0.000 claims abstract description 22
- 239000011159 matrix material Substances 0.000 claims description 74
- 238000004364 calculation method Methods 0.000 claims description 12
- 238000005070 sampling Methods 0.000 claims description 7
- 230000017105 transposition Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 101001093748 Homo sapiens Phosphatidylinositol N-acetylglucosaminyltransferase subunit P Proteins 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/16—Anti-collision systems
- G08G1/166—Anti-collision systems for active traffic, e.g. moving vehicles, pedestrians, bikes
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/16—Matrix or vector computation, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Computational Mathematics (AREA)
- Data Mining & Analysis (AREA)
- Theoretical Computer Science (AREA)
- Computing Systems (AREA)
- Algebra (AREA)
- Databases & Information Systems (AREA)
- Software Systems (AREA)
- General Engineering & Computer Science (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
- Navigation (AREA)
Abstract
The invention provides a multi-vehicle cooperative positioning method in an intelligent traffic system, which can improve the positioning accuracy of vehicles. The method comprises the following steps: calculating a position measurement value of the target vehicle at the next moment according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current moment; acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment; calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles; and substituting the motion equation and the observation equation of the system into the extended Kalman filtering to obtain the position estimation value of the target vehicle. The invention relates to the technical field of wireless positioning.
Description
Technical Field
The invention relates to the technical field of wireless positioning, in particular to a multi-vehicle cooperative positioning method in an intelligent traffic system.
Background
In recent years, as vehicles become more intelligent and automated, in an intelligent transportation system, various safety-related applications, such as real-time estimation of traffic conditions, a collision warning system, a lane departure warning system, and the like, are used to improve the efficiency and safety of driving, thereby reducing vehicle collision accidents. These security applications rely primarily on vehicle location information provided by the local transportation network. Vehicle navigation technologies include the Global Positioning System (GPS), global satellite navigation system (GLONASS), galileo and Beidou systems (BDS), which can provide location information to a vehicle user. GPS is one of the most common positioning devices in vehicle positioning. However, it is well known that GPS signals are subject to different sources of noise and degradation and temporary loss of signal in complex environments, and GPS satellite visibility estimates are inadequate, which makes GPS unable to provide accurate location information in all situations. Our low cost GPS receiver navigation systems for automotive applications suffer from low accuracy and frequent signal interruption problems. Typically, the accuracy of a GPS is nominally about 10m, which is too high for a vehicle active safety system.
One of the most common methods for improving the accuracy of self-positioning is to use other embedded information sources, combine navigation data, and obtain a more accurate position estimation through data fusion. The current technology for improving GPS performance is based on Kalman filtering (Kalman filtering). The main idea of the method based on Kalman filtering is to reduce GPS pseudo-range errors through filtering, but the method does not combine position information of surrounding vehicles, and the positioning accuracy provided in an intelligent transportation system is not high.
Disclosure of Invention
The invention aims to provide a multi-vehicle cooperative positioning method in an intelligent traffic system, so as to solve the problem of low positioning accuracy in the prior art.
In order to solve the above technical problem, an embodiment of the present invention provides a method for cooperatively locating multiple vehicles in an intelligent transportation system, including:
obtaining position observation values of a target vehicle and an adjacent vehicle in a system at the current moment, wherein the adjacent vehicle is a vehicle adjacent to the target vehicle;
obtaining a motion observation value of the target vehicle at the current moment;
calculating a position measurement value of the target vehicle at the next moment according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current moment;
acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment;
calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles;
and substituting the motion equation and the observation equation of the system into the extended Kalman filtering to obtain the position estimation value of the target vehicle.
Further, the obtaining of the position observations of the target vehicle and the neighboring vehicle at the current time in the system comprises:
obtaining a target vehicle X at time k0Is observed at a position of X0k=[x0ky0kθ0k]T;
Where k denotes the current time, T denotes the transpose, and x0kIndicating target vehicle X at time k0In the x-axis, y0kIndicating target vehicle X at time k0In the y-axis coordinate, θ0kIndicating target vehicle X at time k0The included angle formed by the motion direction and the x axis;
obtaining adjacent vehicles X at time kjIs observed at a position of Xjk=[xjkyjkθjk]T,(j=1,2…N);
Wherein N represents the number of adjacent vehicles, xjkIndicating the adjacent vehicle X at time kjIn the x-axis, yjkIndicating the adjacent vehicle X at time kjIn the y-axis coordinate, θjkIndicating the adjacent vehicle X at time kjThe direction of motion forms an angle with the x-axis.
Further, the obtaining of the motion observation value of the target vehicle at the current time includes:
obtaining a target vehicle X at time k0Is observed in the movement u0k=[V0ka0kφ0k]T;
Wherein, V0kIndicating target vehicle X at time k0A velocity of0kIndicating target vehicle X at time k0Acceleration of phi0kIndicating target vehicle X at time k0The steering angle of (c).
Further, the calculating a position measurement value of the target vehicle at the next time according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current time comprises:
according to the target vehicle X0Position observation X at time k0kAnd the motion observation u0kAnd a target vehicle X0Calculating the target vehicle X0Position measurement X at time k +10(k+1)=f(X0k,u0k) Wherein, f (X)0k,u0k) Indicating target vehicle X0Discrete equations of motion of the motion model of (a);
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value X with respect to position0kOf the jacobian matrixComprises the following steps:
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value u about movement0kOf the Jacobian matrix Bu0kComprises the following steps:
further, the acquiring the number of the adjacent vehicles, and combining the acquired position observation value and the acquired motion observation value of the target vehicle at the current moment, and the calculated position measurement value of the target vehicle at the next moment, the constructing a system motion equation comprises:
acquiring the number N of the adjacent vehicles;
combining the acquired position observed value X of the target vehicle at the time k according to the acquired number N of the adjacent vehicles0kAnd the motion observation u0kConstructing a system state of the entire system including the target vehicle and the neighboring vehicle at the time kSystem inputThe equation of motion of the system is Xk+1=f(Xk,uk) (ii) a Wherein T represents a matrix transpose;
according to the Jacobian matrixObtaining the motion equation f (X) of the systemk,uk) About system stateState XkJacobian matrix akComprises the following steps:
according to the Jacobian matrixObtaining the motion equation f (X) of the systemk,uk) About system input ukOf the Jacobian matrix BkComprises the following steps:
further, the calculating the relative position information between the target vehicle and the adjacent vehicle according to the obtained position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing the observation equation of the system according to the number of the adjacent vehicles comprises:
according to the acquired k time, the target vehicle X0Is observed at a position of X0kAnd adjacent vehicle XjIs observed at a position of XjkCalculating the target vehicle X at the time k0And adjacent vehicle XjRelative position information Z therebetweenjk;
According to the calculated k time target vehicle X0And adjacent vehicle XjRelative position information Z therebetweenjkConstructing the observation equation Z of the systemk=[Z1kZ2k… Zjk… Z(N-1)kZNk]T(j ═ 1,2, … N), where N represents the number of adjacent vehicles; wherein, Z isjkExpressed as:
wherein h isj(. h) a calculation formula representing relative positional information, djkIs a target vehicle X0With adjacent vehicle XjThe relative distance between the two or more of them,is a target vehicle X0With adjacent vehicle XjRelative azimuth angle therebetween;
according to Zjk=hj(X0k,Xjk) Target vehicle X0Relative to Zjk=hj(X0k,Xjk) Of the jacobian matrix HjkComprises the following steps:
according to the Jacobian matrix HjkTo obtain an observation equation ZkOf the jacobian matrix HkComprises the following steps:
further, the step of substituting the motion equation and the observation equation of the system into the extended kalman filter to obtain the position estimation value of the target vehicle includes:
will system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkObservation equation ZkOf the jacobian matrix HkAnd equation of motion X of the systemk+1And observation equation ZkSubstituting the target vehicle X into the extended Kalman filtering to obtain the target vehicle X0Position estimate of
Further, the step of substituting the motion equation and the observation equation of the system into the extended kalman filter to obtain the position estimation value of the target vehicle includes:
s1, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkAnd calculating the predicted value of the covariance of the system state at the moment of k +1Wherein, PkThe covariance of the system state at time k, Q the covariance of the error of the position observation, T the matrix transposition, TsIs a sampling period;
s2, according to the observation equation ZkOf the jacobian matrix HkAnd the predicted value of the covariance of the system state at the moment of k +1 is obtained through calculationComputing k +1 time Kalman filter gainWherein R is an observation equation ZkError covariance of (2);
s3, obtaining a Kalman filtering gain K according to the K +1 moment obtained by calculationk+1And calculating the covariance of the system state at the moment k +1Wherein I is an identity matrix;
s4, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkCalculating the predicted value of the system state at the moment k +1And system observation equation predictionWherein,
s5, according to the obtained system observation equation predicted valueDetermination of target vehicle X0With adjacent vehicle XjRelative azimuth angle predicted value therebetweenWhether a preset judgment formula is met or not, and if so, determining the estimated value of the system state at the k +1 momentIf not, determining the estimated value of the system state at the k +1 momentComprises the following steps:
s6, estimating the system state according to the k +1 timeComputingTarget vehicle position estimation value at k +1 momentComprises the following steps:
further, the preset judgment formula is expressed as:
wherein, thetathreshIs a preset threshold value.
Wherein,is a target vehicle X0With adjacent vehicle XjThe variance of the relative azimuth angle therebetween.
The technical scheme of the invention has the following beneficial effects:
according to the scheme, the position measurement value of the target vehicle at the next moment is calculated through the acquired position observation value and the acquired motion observation value of the target vehicle at the current moment; acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment; calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles; substituting a motion equation and an observation equation of the system into the extended Kalman filtering to obtain a position estimation value of the target vehicle; therefore, the position observation value of the target vehicle is combined with the position observation value of the adjacent vehicle, the relative position information between the target vehicle and the adjacent vehicle is calculated, the position of the target vehicle is estimated after filtering is carried out by using the extended Kalman filtering based on the calculated relative position information between the target vehicle and the adjacent vehicle, the cooperative positioning is realized, the position error can be reduced, and the positioning precision of the vehicle is improved.
Drawings
Fig. 1 is a schematic flowchart of a multi-vehicle cooperative positioning method in an intelligent transportation system according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a multi-vehicle system model of an intelligent transportation system according to an embodiment of the invention;
FIG. 3 is a schematic diagram illustrating a comparison between a measured position error and a GPS measured position error according to an embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.
The invention provides a multi-vehicle cooperative positioning method in an intelligent traffic system, aiming at the problem of low positioning accuracy in the prior art.
As shown in fig. 1, a method for cooperatively locating multiple vehicles in an intelligent transportation system according to an embodiment of the present invention includes:
s101, obtaining position observation values of a target vehicle and an adjacent vehicle in a system at the current moment, wherein the adjacent vehicle is a vehicle adjacent to the target vehicle;
s102, obtaining a motion observation value of the target vehicle at the current moment;
s103, calculating a position measurement value of the target vehicle at the next moment according to the acquired position observation value and the acquired motion observation value of the target vehicle at the current moment;
s104, acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment;
s105, calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles;
and S106, substituting the motion equation and the observation equation of the system into the extended Kalman filtering to obtain the position estimation value of the target vehicle.
According to the multi-vehicle cooperative positioning method in the intelligent transportation system, the position measurement value of the target vehicle at the next moment is calculated through the acquired position observation value and the acquired motion observation value of the target vehicle at the current moment; acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment; calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles; substituting a motion equation and an observation equation of the system into the extended Kalman filtering to obtain a position estimation value of the target vehicle; therefore, the position observation value of the target vehicle is combined with the position observation value of the adjacent vehicle, the relative position information between the target vehicle and the adjacent vehicle is calculated, the position of the target vehicle is estimated after filtering is carried out by using the extended Kalman filtering based on the calculated relative position information between the target vehicle and the adjacent vehicle, the cooperative positioning is realized, the position error can be reduced, and the positioning precision of the vehicle is improved.
According to the multi-vehicle cooperative positioning method in the intelligent transportation system, the measurement result is more accurate than the GPS measurement result in the low signal-to-noise ratio environment, the extended Kalman filtering operation speed is high, and the positioning precision of the vehicle is improved. In practical application, the number of adjacent vehicles can be adaptively selected according to practical situations. In the intelligent transportation system, adjacent vehicles around a target vehicle are constantly changed, and the method for cooperatively positioning the multiple vehicles in the intelligent transportation system can autonomously select the number of the adjacent vehicles around the target vehicle.
In an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the obtaining position observations of a target vehicle and an adjacent vehicle at a current time in the system includes:
obtaining a target vehicle X at time k0Is observed at a position of X0k=[x0ky0kθ0k]T;
Where k denotes the current time, T denotes the transpose, and x0kIndicating target vehicle X at time k0In the x-axis, y0kIndicating target vehicle X at time k0In the y-axis coordinate, θ0kIndicating target vehicle X at time k0The included angle formed by the motion direction and the x axis;
obtaining adjacent vehicles X at time kjIs observed at a position of Xjk=[xjkyjkθjk]T,(j=1,2…N);
Wherein N represents the number of adjacent vehicles, xjkIndicating the adjacent vehicle X at time kjIn the x-axis, yjkIndicating the adjacent vehicle X at time kjIn the y-axis coordinate, θjkIndicating the adjacent vehicle X at time kjThe direction of motion forms an angle with the x-axis.
In the present embodiment, the target vehicle X0Target vehicle X at time k can be acquired through vehicle navigation (e.g., GPS device or Beidou device)0Is observed at a position of X0k=[x0ky0kθ0k]T(ii) a At the same time, the target vehicle X0The k-time adjacent vehicle X may be acquired by Short-Range Communication (DSRC)jIs observed at a position of Xjk=[xjkyjkθjk]T(j ═ 1,2 … N), the expenditure is small.
In the present embodiment, θkIndicating target vehicle X at time k0The angle formed by the direction of movement and the X-axis, i.e. the target vehicle X at time k0The azimuth of (d); thetajkIndicating the adjacent vehicle X at time kjThe angle formed by the direction of movement and the X-axis, i.e. the adjacent vehicle X at time kjIs measured.
In an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the obtaining a motion observation value of the target vehicle at the current time includes:
obtaining a target vehicle X at time k0Is observed in the movement u0k=[V0ka0kφ0k]T;
Wherein, V0kIndicating target vehicle X at time k0A velocity of0kIndicating target vehicle X at time k0Acceleration of phi0kIndicating target vehicle X at time k0The steering angle of (c).
In this embodiment, the target vehicle X at time k may be acquired by the vehicle-mounted sensor0Is observed in the movement u0k=[V0ka0kφ0k]TWherein the onboard sensors may include, but are not limited to: acceleration sensor, speed sensor.
In an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the calculating, according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current time, a position measurement value of the target vehicle at a next time includes:
according to the target vehicle X0Position observation X at time k0kAnd the motion observation u0kAnd a target vehicle X0Calculating the target vehicle X0Position measurement X at time k +10(k+1)=f(X0k,u0k) Wherein, f (X)0k,u0k) Indicating target vehicle X0Discrete equations of motion of the motion model of (a);
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value X with respect to position0kOf the jacobian matrixComprises the following steps:
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value u about movement0kOf the jacobian matrixComprises the following steps:
in an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the acquiring the number of the neighboring vehicles, and combining the acquired position observed value and motion observed value of the target vehicle at the current time, and the calculated position measured value of the target vehicle at the next time, constructing a motion equation of the system includes:
acquiring the number N of the adjacent vehicles;
combining the acquired position observed value X of the target vehicle at the time k according to the acquired number N of the adjacent vehicles0kAnd the motion observation u0kConstructing a system state of the entire system including the target vehicle and the neighboring vehicle at the time kSystem inputThe equation of motion of the system is Xk+1=f(Xk,uk) (ii) a Wherein T represents a matrix transpose;
according to the Jacobian matrixObtaining the motion equation f (X) of the systemk,uk) About System State XkJacobian matrix akComprises the following steps:
according to the Jacobian matrixObtaining the motion equation f (X) of the systemk,uk) About system input ukOf the Jacobian matrix BkComprises the following steps:
in an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the calculating, according to the obtained position observed values of the target vehicle and the adjacent vehicles at the current time, relative position information between the target vehicle and the adjacent vehicles, and constructing an observation equation of the system according to the number of the adjacent vehicles includes:
according to the acquired k time, the target vehicle X0Is observed at a position of X0kAnd adjacent vehicle XjIs observed at a position of XjkCalculating the target vehicle X at the time k0And adjacent vehicle XjRelative position information Z therebetweenjk;
According to the calculated k time target vehicle X0And adjacent vehicle XjRelative position information Z therebetweenjkConstructing the observation equation Z of the systemk=[Z1kZ2k… Zjk… Z(N-1)kZNk]T(j ═ 1,2, … N), where N represents the number of adjacent vehicles; wherein, Z isjkExpressed as:
wherein h isj(. h) a calculation formula representing relative positional information, djkIs a target vehicle X0With adjacent vehicle XjThe relative distance between the two or more of them,is a target vehicle X0With adjacent vehicle XjRelative azimuth angle therebetween;
according to Zjk=hj(X0k,Xjk) Target vehicle X0Relative to Zjk=hj(X0k,Xjk) Of the jacobian matrix HjkComprises the following steps:
according to the Jacobian matrix HjkTo obtain an observation equation ZkOf the jacobian matrix HkComprises the following steps:
in an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the substituting a motion equation and an observation equation of the system into the extended kalman filter to obtain the position estimation value of the target vehicle includes:
will system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkObservation equation ZkOf the jacobian matrix HkAnd equation of motion X of the systemk+1And observation equation ZkSubstituting the target vehicle X into the extended Kalman filtering to obtain the target vehicle X0Position estimate of
In an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, further, the substituting a motion equation and an observation equation of the system into the extended kalman filter to obtain the position estimation value of the target vehicle includes:
s1, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkAnd calculating the predicted value of the covariance of the system state at the moment of k +1Wherein, PkThe covariance of the system state at time k, Q the covariance of the error of the position observation, T the matrix transposition, TsIs a sampling period;
s2, according to the observation equation ZkOf the jacobian matrix HkAnd the predicted value of the covariance of the system state at the moment of k +1 is obtained through calculationComputing k +1 time Kalman filter gainWherein R is an observation equation ZkError covariance of (2);
s3, obtaining a Kalman filtering gain K according to the K +1 moment obtained by calculationk+1And calculating the covariance of the system state at the moment k +1Wherein I is an identity matrix;
s4, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkCalculating the predicted value of the system state at the moment k +1And system observation equation predictionWherein,
s5, according to the obtained system observation equation predicted valueDetermination of target vehicle X0With adjacent vehicle XjRelative azimuth angle predicted value therebetweenWhether a preset judgment formula is met or not, and if so, determining the estimated value of the system state at the k +1 momentIf not, determining the estimated value of the system state at the k +1 momentComprises the following steps:
S6, estimating the system state according to the k +1 timeCalculating the estimated value of the position of the target vehicle at the moment k +1Comprises the following steps:
in an embodiment of the foregoing method for cooperatively locating multiple vehicles in an intelligent transportation system, the preset determination formula is further expressed as:
wherein, thetathreshIs a preset threshold value.
In S5, the judgment can be made by a predetermined judgment formulaDetermination of target vehicle X0With adjacent vehicle XjRelative azimuth angle predicted value therebetweenWhether or not to approachIf approachingThe system state prediction value is retainedNamely the estimated value of the system state at the moment of k +1If not close, k +1 time system state estimationComprises the following steps:
in the foregoing embodiment of the method for cooperative positioning of multiple vehicles in an intelligent transportation system, further, the method includes
Wherein,is a target vehicle X0With adjacent vehicle XjThe variance of the relative azimuth angle therebetween.
As shown in fig. 2, a detailed description is given of the multi-vehicle cooperative positioning method in the intelligent transportation system according to this embodiment by using a specific example, and a matlab simulation platform is used to perform simulation analysis on the performance of the multi-vehicle cooperative positioning method in the intelligent transportation system according to this embodiment:
step 1, as shown in FIG. 2, consider a target vehicle X in an intelligent transportation system0And four adjacent vehicles X1,X2,X3,X4On the road, vehicle X0,X1,X2,X3,X4Respectively receiving respective position observation values at the k moments through own GPS equipment;
step 3, according to the target vehicle X0Obtaining the position observed value and the motion observed value of the target vehicle at the moment k +1, namely the target vehicle X0The motion model of (2); specifically, step 3 may include:
3.1) target vehicle X0The discrete equation of motion of the motion model of (1) is:
wherein, TsIs the sampling period.
3.2) according to the equation of discrete motion f (X)0k,u0k) Obtaining f (X)0k,u0k) With respect to X0kOf the jacobian matrixComprises the following steps:
3.3) according to the equation of discrete motion f (X)0k,u0k) Obtaining f (X)0k,u0k) About u0kOf the jacobian matrixComprises the following steps:
4.1) Jacobian matrix according to step 3Equation of motion f (X) of the resulting systemk,uk) About System State XkJacobian matrix akComprises the following steps:
4.2) Jacobian matrix according to step 3Equation of motion f (X) of the resulting systemk,uk) About system input ukOf the Jacobian matrix BkComprises the following steps:
and 5: calculating to obtain the relative position information between the target vehicle and the adjacent vehicle, and constructing an observation equation Zk=[Z1kZ2kZ3kZ4k]TSpecifically, step 5 may include:
5.1) k time target vehicle X0With adjacent vehicle XjRelative position information Z therebetweenjkComprises the following steps:
wherein d isjkIs a target vehicle X0With adjacent vehicle XjThe relative distance between the two or more of them,is a target vehicle X0With adjacent vehicle XjRelative azimuth angle therebetween;
5.2) target vehicle X0Relative to Zjk=hj(X0k,Xjk) Of the jacobian matrix HjkComprises the following steps:
5.3) according to the Jacobian matrix HjkAvailable observation equation ZkOf the jacobian matrix HkComprises the following steps:
Wherein, PkIs the covariance of the system state at time k, Q is the covariance of the position observation error, TsIs a sampling period;
Wherein R is an observation equation ZkError covariance of (H)kFor the observation of equation ZkA jacobian matrix.
6.3) Kalman filter gain K according to the K +1 momentk+1Obtaining the covariance P of the system state at the moment of k +1k+1:
Where I is the identity matrix, HkFor the observation of equation ZkA jacobian matrix.
6.4) according to the System State XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkComputing system state prediction values
6.5) calculating the estimated value of the system state at the moment k +1The predicted value of the system observation equation obtained according to 6.4)Determination of target vehicle X0With adjacent vehicle XjRelative azimuth angle predicted value therebetweenWhether or not to approachIf approachingThe system state prediction value is retainedNamely, it isIf not, then
Wherein,Kk+1kalman filter gain at time k +1, Zk+1Is the observed value of the system observation equation at the moment k +1,and the predicted value is the system state value at the moment k + 1.
6.6) calculated according to 6.5)The estimated value of the position of the target vehicle at the moment of k +1 can be obtainedComprises the following steps:
in this embodiment, as shown in fig. 3, fig. 3 is a schematic diagram illustrating a comparison between a position error measured by an embodiment of the present invention and a position error measured by a GPS, where an abscissa in fig. 3 is a sampling time and an ordinate is a position error size, and the result is obtained by performing 1000 experiments with the same conditions under a signal-to-noise ratio of 3 dB. As can be seen from fig. 3, the method proposed by the embodiment of the present invention reduces the position error and provides a more accurate position estimate. This shows that the cooperative positioning method proposed by the embodiment of the present invention is accurate and effective, and the comparison result also shows that the performance of the method adopted by the present invention is superior to the performance of the GPS measurement.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (5)
1. A multi-vehicle cooperative positioning method in an intelligent transportation system is characterized by comprising the following steps:
obtaining position observation values of a target vehicle and an adjacent vehicle in a system at the current moment, wherein the adjacent vehicle is a vehicle adjacent to the target vehicle;
obtaining a motion observation value of the target vehicle at the current moment;
calculating a position measurement value of the target vehicle at the next moment according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current moment;
acquiring the number of the adjacent vehicles, and constructing a motion equation of the system by combining the acquired position observation value and motion observation value of the target vehicle at the current moment and the calculated position measurement value of the target vehicle at the next moment;
calculating relative position information between the target vehicle and the adjacent vehicle according to the acquired position observation values of the target vehicle and the adjacent vehicle at the current moment, and constructing an observation equation of the system according to the number of the adjacent vehicles;
substituting a motion equation and an observation equation of the system into the extended Kalman filtering to obtain a position estimation value of the target vehicle;
wherein the calculating a position measurement value of the target vehicle at the next moment according to the obtained position observation value and the obtained motion observation value of the target vehicle at the current moment comprises:
according to the target vehicle X0Position observation X at time k0kAnd the motion observation u0kAnd a target vehicle X0Calculating the target vehicle X0Position measurement X at time k +10(k+1)=f(X0k,u0k) Wherein, f (X)0k,u0k) Indicating target vehicle X0Discrete equations of motion of the motion model of (a);
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value X with respect to position0kOf the jacobian matrixComprises the following steps:
according to f (X)0k,u0k) Obtaining f (X)0k,u0k) Observed value u about movement0kOf the jacobian matrixComprises the following steps:
the acquiring the number of the adjacent vehicles, and combining the acquired position observed value and the acquired motion observed value of the target vehicle at the current moment and the calculated position measured value of the target vehicle at the next moment, the constructing a motion equation of the system comprises:
acquiring the number N of the adjacent vehicles;
combining the acquired position observed value X of the target vehicle at the time k according to the acquired number N of the adjacent vehicles0kAnd the motion observation u0kConstructing a system state of the entire system including the target vehicle and the neighboring vehicle at the time kSystem inputThe equation of motion of the system is Xk+1=f(Xk,uk) (ii) a Wherein T represents a matrix transpose;
according to the Jacobian matrix AX0kTo obtain the motion equation f (X) of the systemk,uk) About System State XkJacobian matrix akComprises the following steps:
according to the Jacobian matrixObtaining the motion equation f (X) of the systemk,uk) About system input ukOf the Jacobian matrix BkComprises the following steps:
wherein, according to the obtained position observed values of the target vehicle and the adjacent vehicles at the current moment, calculating the relative position information between the target vehicle and the adjacent vehicles, and according to the number of the adjacent vehicles, constructing the observation equation of the system comprises:
according to the acquired k time, the target vehicle X0Is observed at a position of X0kAnd adjacent vehicle XjIs observed at a position of XjkCalculating the target vehicle X at the time k0And adjacent vehicle XjRelative position information Z therebetweenjk;
According to the calculated k time target vehicle X0And adjacent vehicle XjRelative position information Z therebetweenjkConstructing the observation equation Z of the systemk=[Z1kZ2k…Zjk…Z(N-1)kZNk]TJ ═ 1,2, … N, where N represents the number of adjacent vehicles; wherein, Z isjkExpressed as:
wherein h isj(. h) a calculation formula representing relative positional information, djkIs a target vehicle X0With adjacent vehicle XjThe relative distance between the two or more of them,is a target vehicle X0With adjacent vehicle XjRelative azimuth angle therebetween;
according to Zjk=hj(X0k,Xjk) Target vehicle X0Relative to Zjk=hj(X0k,Xjk) Of the jacobian matrix HjkComprises the following steps:
according to the Jacobian matrix HjkTo obtain an observation equation ZkOf the jacobian matrix HkComprises the following steps:
substituting the motion equation and the observation equation of the system into the extended Kalman filtering to obtain the position estimation value of the target vehicle comprises:
s1, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkAnd calculating the predicted value of the covariance of the system state at the moment of k +1Wherein, PkThe covariance of the system state at time k, Q the covariance of the error of the position observation, T the matrix transposition, TsIs a sampling period;
s2, according to the observation equation ZkOf the jacobian matrix HkAnd the predicted value of the covariance of the system state at the moment of k +1 is obtained through calculationComputing k +1 time Kalman filter gainWherein R is an observation equation ZkError covariance of (2);
s3, obtaining a Kalman filtering gain K according to the K +1 moment obtained by calculationk+1And calculating the covariance of the system state at the moment k +1Wherein I is an identity matrix;
s4, according to the system state XkJacobian matrix akAnd system input ukOf the Jacobian matrix BkCalculating the predicted value of the system state at the moment k +1And system observation equation predictionWherein,
s5, according to the obtained system observation equation predicted valueDetermination of target vehicle X0With adjacent vehicle XjRelative azimuth angle predicted value therebetweenWhether a preset judgment formula is met or not, and if so, determining the estimated value of the system state at the k +1 momentIf not, determining the estimated value of the system state at the k +1 momentComprises the following steps:
s6, estimating the system state according to the k +1 timeCalculating the estimated value of the position of the target vehicle at the moment k +1Comprises the following steps:
2. the method for cooperative positioning of multiple vehicles in an intelligent transportation system according to claim 1, wherein the obtaining of the position observation values of the target vehicle and the adjacent vehicle at the current time in the system comprises:
obtaining a target vehicle X at time k0Is observed at a position of X0k=[x0ky0kθ0k]T;
Where k denotes the current time, T denotes the transpose, and x0kIndicating target vehicle X at time k0In the x-axis, y0kIndicating target vehicle X at time k0In the y-axis coordinate, θ0kIndicating target vehicle X at time k0The included angle formed by the motion direction and the x axis;
obtaining adjacent vehicles X at time kjIs observed at a position of Xjk=[xjkyjkθjk]T,j=1,2…N;
Wherein N represents the number of adjacent vehicles, xjkIndicating the adjacent vehicle X at time kjIn the x-axis, yjkIndicating the adjacent vehicle X at time kjIn the y-axis coordinate, θjkIndicating the adjacent vehicle X at time kjThe direction of motion forms an angle with the x-axis.
3. The method for cooperatively positioning multiple vehicles in the intelligent transportation system according to claim 1, wherein the obtaining of the observed value of the motion of the target vehicle at the current time comprises:
obtaining a target vehicle X at time k0Is observed in the movement u0k=[V0ka0kφ0k]T;
Wherein, V0kIndicating target vehicle X at time k0A velocity of0kIndicating target vehicle X at time k0Acceleration of phi0kIndicating target vehicle X at time k0The steering angle of (c).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710423028.XA CN107274721B (en) | 2017-06-07 | 2017-06-07 | Multi-vehicle cooperative positioning method in intelligent transportation system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710423028.XA CN107274721B (en) | 2017-06-07 | 2017-06-07 | Multi-vehicle cooperative positioning method in intelligent transportation system |
Publications (2)
Publication Number | Publication Date |
---|---|
CN107274721A CN107274721A (en) | 2017-10-20 |
CN107274721B true CN107274721B (en) | 2020-03-31 |
Family
ID=60066432
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201710423028.XA Expired - Fee Related CN107274721B (en) | 2017-06-07 | 2017-06-07 | Multi-vehicle cooperative positioning method in intelligent transportation system |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN107274721B (en) |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108398704B (en) * | 2018-02-06 | 2020-11-06 | 北京科技大学 | Bayesian filtering multi-vehicle cooperative positioning method |
CN108519738A (en) * | 2018-04-13 | 2018-09-11 | 中国科学院微电子研究所 | Vehicle motion state information delay compensation method and device |
FR3084151B1 (en) * | 2018-07-23 | 2020-06-19 | Safran | METHOD AND DEVICE FOR AIDING THE NAVIGATION OF A FLEET OF VEHICLES USING AN INVARIANT KALMAN FILTER |
CN111912413B (en) * | 2020-07-23 | 2022-04-19 | 腾讯科技(深圳)有限公司 | Positioning method and device |
CN113706854B (en) * | 2021-08-20 | 2023-03-07 | 北京科技大学 | Vehicle cooperative positioning method in intelligent Internet of vehicles |
CN113870489B (en) * | 2021-09-10 | 2023-02-07 | 摩拜(北京)信息技术有限公司 | Vehicle positioning method and device and vehicle |
CN113963551B (en) * | 2021-10-18 | 2022-09-27 | 中国电力科学研究院有限公司 | Vehicle positioning method, system, device and medium based on cooperative positioning |
CN114608590B (en) * | 2022-03-09 | 2024-04-30 | 吉林大学 | Multi-vehicle tracking method based on intelligent reflecting surface in severe environment |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1934513A (en) * | 2004-02-25 | 2007-03-21 | 学校法人立命馆 | Control system of floating mobile body |
CN102077259A (en) * | 2009-02-27 | 2011-05-25 | 丰田自动车株式会社 | Vehicle relative position estimation apparatus and vehicle relative position estimation method |
CN102192745A (en) * | 2010-02-24 | 2011-09-21 | 歌乐株式会社 | Position estimation device and position estimation method |
CN104282020A (en) * | 2014-09-22 | 2015-01-14 | 中海网络科技股份有限公司 | Vehicle speed detection method based on target motion track |
CN105682222A (en) * | 2016-03-01 | 2016-06-15 | 西安电子科技大学 | Vehicle location positioning information fusion method based on vehicular ad hoc network |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016170635A1 (en) * | 2015-04-23 | 2016-10-27 | 三菱電機株式会社 | Leading vehicle selection assistance device, travel plan creation device, leading vehicle selection assistance method, and travel plan creation method |
-
2017
- 2017-06-07 CN CN201710423028.XA patent/CN107274721B/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1934513A (en) * | 2004-02-25 | 2007-03-21 | 学校法人立命馆 | Control system of floating mobile body |
CN102077259A (en) * | 2009-02-27 | 2011-05-25 | 丰田自动车株式会社 | Vehicle relative position estimation apparatus and vehicle relative position estimation method |
CN102192745A (en) * | 2010-02-24 | 2011-09-21 | 歌乐株式会社 | Position estimation device and position estimation method |
CN104282020A (en) * | 2014-09-22 | 2015-01-14 | 中海网络科技股份有限公司 | Vehicle speed detection method based on target motion track |
CN105682222A (en) * | 2016-03-01 | 2016-06-15 | 西安电子科技大学 | Vehicle location positioning information fusion method based on vehicular ad hoc network |
Also Published As
Publication number | Publication date |
---|---|
CN107274721A (en) | 2017-10-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107274721B (en) | Multi-vehicle cooperative positioning method in intelligent transportation system | |
CN111307162B (en) | Multi-sensor fusion positioning method for automatic driving scene | |
CN107315413B (en) | Multi-vehicle cooperative positioning algorithm considering relative positions between vehicles in vehicle-vehicle communication environment | |
CN106840179B (en) | Intelligent vehicle positioning method based on multi-sensor information fusion | |
CN109946731B (en) | Vehicle high-reliability fusion positioning method based on fuzzy self-adaptive unscented Kalman filtering | |
CN110140065B (en) | GNSS receiver protection level | |
CN106289275B (en) | Unit and method for improving positioning accuracy | |
CN111770451B (en) | Road vehicle positioning and sensing method and device based on vehicle-road cooperation | |
US10698100B2 (en) | Method and device for determining the position of a vehicle | |
Al-Khedher | Hybrid GPS-GSM localization of automobile tracking system | |
US9162682B2 (en) | Method and device for determining the speed and/or position of a vehicle | |
EP3680877A1 (en) | Method for determining the location of an ego-vehicle | |
Li et al. | Simultaneous registration and fusion of multiple dissimilar sensors for cooperative driving | |
CN104808220B (en) | Vehicle localization integrity monitoring method based on wireless information interaction | |
EP3644016B1 (en) | Localization using dynamic landmarks | |
CN107132563B (en) | Combined navigation method combining odometer and dual-antenna differential GNSS | |
WO2018072350A1 (en) | Vehicle trajectory prediction method and device | |
CN102928816A (en) | High-reliably integrated positioning method for vehicles in tunnel environment | |
CN104835353A (en) | Cooperation relative positioning method based on INS and GNSS pseudo-range double difference for VANET | |
CN108974054B (en) | Seamless train positioning method and system | |
US11585945B2 (en) | Method for the satellite-supported determination of a position of a vehicle | |
CN109946648B (en) | Ultra-wideband-based high-precision vehicle positioning method under cooperation of vehicle and road | |
CN112346103A (en) | V2X-based intelligent networking automobile dynamic co-location method and device | |
CN112147651B (en) | Asynchronous multi-vehicle cooperative target state robust estimation method | |
Suwandi et al. | Low-cost IMU and GPS fusion strategy for apron vehicle positioning |
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 | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20200331 |