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CN-116699652-B - Navigation system group fault detection and identification method based on collaborative navigation information common mode combination

CN116699652BCN 116699652 BCN116699652 BCN 116699652BCN-116699652-B

Abstract

The invention discloses a fault detection and identification method of a navigation system group combined by collaborative navigation information and common mode, which utilizes a collaborative system to construct a common mode pseudo range residual error to improve the fault detection sensitivity of a GNSS receiver, utilizes the collaborative characteristic of the cluster system to improve the identification efficiency of a fault satellite, carries out combined modeling on the observed quantity of an auxiliary sensor in the collaborative navigation system and the pseudo range observed quantity of the GNSS receiver, and can also detect whether the auxiliary sensor has faults after monitoring the integrity of the GNSS receiver. According to the method, different factors inducing pseudo-range faults can be dealt with in a complex environment, the distributed fault processing is adopted, the fault detection rate and the recognition rate of the GNSS receiver in the collaborative navigation system are improved, the faults of auxiliary sensors in the collaborative navigation system are detected and recognized, the integrity of the whole collaborative navigation system is improved, and the accuracy and the robustness of the navigation system are guaranteed.

Inventors

  • WANG RONG
  • LIU YAOKAI
  • HE HUI
  • XIONG ZHI
  • LIU JIANYE
  • ZHAO WEICHENG
  • GU CHEN
  • WANG SICHEN

Assignees

  • 南京航空航天大学

Dates

Publication Date
20260505
Application Date
20230605

Claims (8)

  1. 1. The navigation system group fault detection and identification method based on collaborative navigation information common mode combination is characterized by comprising the following steps: Step 1), each aircraft in a cluster system acquires satellite pseudo-range observation values by using a GNSS receiver, acquires relative distance information between the aircraft by using a data chain as an auxiliary sensor, and establishes an observation equation according to the satellite pseudo-range observation values and the relative distance observation values; The number of the clustered aircrafts is Wherein one aircraft is the target aircraft , While the rest are used as auxiliary aircrafts , Target aircraft Auxiliary aircraft The number of visible satellites is respectively And ; Step 1.1), satellite pseudo-range observation values of all aircrafts in a cluster system are calculated, and the aircrafts are assisted The pseudo-range observation equation of (2) is: ; Wherein, the To assist aircraft Currently all visible satellites go to the first Pseudo-range measurements for the individual satellites in view, , To assist aircraft To satellite Is a true value of the distance of (2), In order to achieve the light velocity, the light beam is, Is an aircraft The clock error of the on-board GNSS device, Including satellite clock bias, ionosphere, troposphere delay, and error pseudorange noise due to signal multipath and non-line of sight; Step 1.2), calculating a target aircraft To auxiliary aircraft The relative distance observation equation of (2) is: ; Wherein, the For aircraft of interest To auxiliary aircraft Is used to measure the relative distance of the two, For aircraft of interest To auxiliary aircraft Is a true value on the relative distance of (2), For aircraft of interest The clock skew of the on-board data link system, To assist aircraft The clock skew of the on-board data link system, Measuring noise of the data link system; Step 2), in a cluster network, information interaction is carried out among all aircrafts, the respective observed quantity is shared, and each aircraft unit carries out linearization processing on an observation equation of the aircraft unit and calculates corresponding pseudo-range residual errors and relative distance residual errors; step 2.1), calculating an auxiliary aircraft To the current visible satellite Geometric distance of (2) The method comprises the following steps: ; Wherein, the To assist aircraft Visible satellite of (a) Is a three-dimensional position coordinate under the Earth Fixed coordinate system (Earth-Centered, earth Fixed, ECEF) , To assist aircraft Is a three-dimensional position coordinate under the earth fixed coordinate system ; Step 2.2) the auxiliary aircraft is set To its visible satellite The geometric distance of (2) is subjected to Taylor series expansion and linearization, and the converted expression is as follows: ; ; Wherein, the Respectively auxiliary aircrafts A position error in the X, Y, Z direction under the ECEF coordinate system, 、 、 Respectively auxiliary aircrafts And satellite The direction cosine in the direction X, Y, Z, Position errors representing visible satellites are found to be directional cosine; Step 2.3), calculating an auxiliary aircraft To its visible satellite Obtaining an auxiliary aircraft from the difference between the calculated distance value and the measured value of (2) The pseudorange residuals are: ; Step 2.4), calculating a target aircraft Auxiliary aircraft The geometric calculation distance of (2) is as follows: ; Wherein, the For aircraft of interest Is the three-dimensional position coordinate under ECEF coordinate system , To assist aircraft Is the three-dimensional position coordinate under ECEF coordinate system ; Step 2.5), the target aircraft is set Auxiliary aircraft The geometric calculation distance of (2) is subjected to Taylor series expansion and linearization, and the converted expression is as follows: ; ; Wherein, the Respectively target aircraft A position error in the X, Y, Z direction under the ECEF coordinate system, 、 、 Respectively auxiliary aircrafts With the target aircraft The direction cosine in the direction X, Y, Z, Representation pair auxiliary aircraft Position error solving direction cosine; step 2.6), calculating a target aircraft To aircraft Relative distance residual of (2) The method comprises the following steps: ; step 2.7) according to the auxiliary aircraft Obtaining target aircraft in cluster system by pseudo-range residual error of (C) Pseudo-range residual of (2) The method comprises the following steps: ; Wherein, the For aircraft of interest Currently all visible satellites go to the first Pseudo-range measurements for the individual satellites in view, , For aircraft of interest To its visible satellite Is used for the distance calculation of (a), 、 、 Respectively target aircraft With visible satellites A direction cosine in X, Y, Z directions; step 3), each aircraft constructs respective observation matrixes according to the visible satellites and the distance information to other aircraft, establishes a pseudo-range residual error and relative distance residual error combined model, performs normalization processing on the measurement noise of the observed quantity, and calculates a state estimation solution of the target aircraft; Step 3.1), target aircraft Auxiliary aircraft Respectively constructing an observation matrix according to pseudo-range observation information and relative distance information of the self And Wherein the target aircraft Is of (1) From satellite observation matrices And observation matrices for other auxiliary aircraft The composition is specifically as follows: ; ; step 3.2), target aircraft According to which to an auxiliary aircraft Is the relative distance residual and target aircraft The pseudo-range residuals of (a) are modeled in combination as follows: ; Wherein, the For aircraft of interest Is used for the distance residual error observation quantity, As a state quantity of the target aircraft, Measuring noise for an on-board sensor of the target aircraft; Step 3.3), selecting a weighting matrix Normalizing the variance of the pseudo-range measurement noise and the variance of the measurement noise, and weighting matrix The specific format of (2) is as follows: ; Wherein, the For the variance of the noise of the pseudorange observations, Is the variance of the ranging noise; Step 3.4), calculating the estimated error vector according to the weighted least square principle Target aircraft when square sum of minimum value is taken Weighted least squares state estimation solution of (2) The method comprises the following steps: ; Wherein, the A weighting matrix corresponding to the target aircraft; step 4), broadcasting the serial numbers and the quantity information of the visible satellites of each aircraft in a trunking network, comparing the serial numbers of the visible satellites of the target aircraft with the serial numbers of all the visible satellites of other aircrafts, and recording the visible satellites with the same serial numbers; step 5), selecting all auxiliary aircrafts with which common mode satellites exist in the cluster system by the target aircrafts, calculating to obtain respective pseudo-range residual vectors according to each aircraft observation matrix, and constructing common mode pseudo-range residual statistical detection quantity; step 6), optimizing the common mode pseudo range residual error statistics detection quantity, and calculating and selecting auxiliary aircrafts to construct common mode detection statistics in the navigation system before the fault detection of the target aircrafts, so that the current fault detection performance of the navigation system can be optimal; step 7), calculating a fault detection threshold value of the target aircraft, comparing the fault detection threshold value with the common mode pseudo-range residual error statistical detection quantity of the target aircraft, and judging whether a pseudo-range measurement fault occurs or not; Step 8), if the fault exists, the target aircraft identifies the fault and eliminates the corresponding fault, and if the system has no pseudo-range fault, whether a data link used in the collaborative navigation system has the fault is further judged; step 9), the target aircraft utilizes the combined model to construct cooperative detection statistics, calculates a cooperative detection threshold value, compares the cooperative statistical detection amount and the cooperative detection threshold value, and judges whether the relative distance information of the data chain has faults or not; Step 10), if the data link measurement fault exists in the system, fault identification and isolation processing are carried out.
  2. 2. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 1, wherein the specific steps of the step 4) are as follows: Step 4.1), each aircraft detects all visible satellite information of the aircraft and interacts in a cluster network, so that each aircraft can observe visible satellite numbers and quantity information of other aircraft in real time Is set as visible satellite number Auxiliary aircraft Is set as visible satellite number ; Step 4.2), the target aircraft root compares the set of visible satellite numbers of the target aircraft root with the set of visible satellite numbers of other auxiliary aircraft, if the same visible satellite numbers exist, namely the target aircraft Auxiliary aircraft Is a common mode satellite of (1), and stores the satellite number in the target aircraft Auxiliary aircraft Common mode satellite set of (2) In which, in the process, For aircraft of interest Auxiliary aircraft Is a common mode satellite number of (c).
  3. 3. The method for detecting and identifying the fault of the navigation system group by combining the collaborative navigation information and the common mode according to claim 2, wherein the specific steps of the step 5) are as follows: Step 5.1), extracting the information about the target aircraft in step 3.3) State estimation solution for pseudo-range observables The method comprises the following steps: ; Wherein the method comprises the steps of For aircraft of interest Is used to estimate the amount of pseudorange residual errors, For aircraft of interest Is a pseudo-range observation weighting matrix; Step 5.2), calculating a target aircraft And an auxiliary aircraft with which a common mode satellite exists The pseudo-range residual vectors of (a) are respectively: ; ; Wherein, the 、 Respectively target aircraft Auxiliary aircraft Measuring noise by pseudo range; To assist aircraft Is a pseudo-range weighting matrix of (a); To assist aircraft Is a pseudo-range residual vector of (a); Step 5.3) within the clustered network, the target aircraft Auxiliary aircraft for simultaneously acquiring other common modes Pseudo-range measurements of (a), assisting aircraft The number of (2) is Corresponding to any given moment, the target aircraft except its own pseudo-range residual vector In addition, can obtain The common mode pseudo-range residual vectors are recorded as , Therefore, the common mode pseudo range residual error detection statistic is constructed in the cooperative environment The method comprises the following steps: ; Wherein, the Auxiliary aircraft for all satellites in common mode with the target aircraft Is a pseudo-range weighting matrix for (a).
  4. 4. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 3, wherein the step 6) comprises the following specific steps: Step 6.1), in the current navigation system, each of the aircraft, when constructing the common mode pseudo-range residual vector, is according to the common mode satellite set in step 4.2) Each auxiliary aircraft in a computing cluster system Relative to a target aircraft The common mode satellite specific gravity of (2) is: ; Wherein, the To assist aircraft With the target aircraft Is a common mode satellite specific gravity of (2); Step 6.2), matching and screening the auxiliary aircrafts according to the calculated common mode satellite specific gravity and each auxiliary aircraft Relative target aircraft Is compared with the common mode Wei Xingzhan in descending order, and when the common mode detection statistic is calculated, an auxiliary aircraft with the highest common mode satellite proportion in the current aircraft is added to assist in constructing the detection statistic as follows And calculate the corresponding detection threshold as : ; ; Wherein, the For the total number of auxiliary aircrafts constructing detection statistics in the current system, the pseudo-range residual error vector corresponding to the target aircraft and the auxiliary aircrafts screened at the moment is , , For the pseudorange weighting matrices of the assisting aircraft in the assisting aircraft matching scheme that participate in the construction of the common mode detection statistic, For a given false alarm rate for the system, For the number of visible satellites of the screened auxiliary aircraft, Is that An inverse cumulative distribution function of the distribution; Step 6.3) according to And Calculating the system limit ratio of fault detection of screened target aircraft The method comprises the following steps: ; Step 6.4), comparing the current system limit ratio And the last system limit ratio, if the current system limit ratio Step 6.2) is carried out in a jumping mode, if the calculated system limit ratio is larger than or equal to the last system limit ratio, otherwise, the auxiliary aircraft screened out by the last calculated system limit ratio is taken, and the maximum value of the system limit ratio is obtained, namely, the maximum value represents that the fault detection performance is optimal; step 6.5), selecting an auxiliary aircraft matching scheme corresponding to the maximum system limit ratio as a common mode auxiliary aircraft assistance target aircraft Fault detection is performed according to the method in step 7).
  5. 5. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 4, wherein the specific steps of the step 7) are as follows: step 7.1), calculating fault detection thresholds of all aircrafts through preset false alarm rates, wherein the calculation formula of the fault detection thresholds is as follows: ; Wherein, the For aircraft of interest There is no probability of a pseudorange failure, Is of degree of freedom of Is a function of the probability density of the chi-square distribution, A false alarm rate given to the system; step 7.2) by comparing common mode pseudorange residual detection statistics And a fault detection threshold Judging whether satellite faults exist or not, when > And when the satellite fault is detected by the system.
  6. 6. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 5, wherein the specific steps of the step 8) are as follows: step 8.1), when a fault is detected in step 7.2), identifying the fault, the target aircraft Eliminating self pseudo-range fault, and constructing fault identification statistics by adopting a Bardan data detection method The method comprises the following steps: ; Wherein, the For aircraft of interest Pseudo-range residual vector of (2) The number of elements to be added to the composition, Is the standard deviation of the pseudo-range observation noise, For aircraft of interest Residual sensitivity matrix Is the first of (2) Line 1 Elements of a column; step 8.2), calculating a target aircraft The failure recognition threshold value of (2) is calculated as follows: ; Wherein, the Representing a target aircraft The probability that the identification statistic of (c) is greater than the fault detection threshold, For aircraft of interest Is set to be a fault identification threshold value of (c), As a function of the probability density of a standard normal distribution, For the failure to identify a threshold value, Number of visible satellites for the aircraft; step 8.3), comparing the pseudo-range fault identification statistic calculated in step 8.1) with the fault identification threshold value calculated in step 8.2), performing pseudo-range fault identification, and isolating the identified fault; Step 8.4), after the detection, identification and elimination of the pseudo-range fault are completed, the combination model in step 3.1) is utilized to detect and identify the range fault of the data link according to step 9).
  7. 7. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 6, wherein the specific steps of the step 9) are as follows: Step 9.1), according to the target aircraft Calculating a target aircraft Is a collaborative residual vector of (1) The method comprises the following steps: ; wherein a matrix is provided Is a collaborative residual error sensitive matrix; step 9.2), calculating a target aircraft according to the following formula Is a collaborative residual weighted sum of squares : ; Step 9.3), calculating the post-verification weight error of the weighted sum of squares of the collaborative residual errors Cooperative detection statistics for a target aircraft: ; Step 9.4), calculating a cooperative fault detection threshold of each aircraft through a false alarm rate given by the system, wherein a formula for calculating the fault detection threshold is as follows: ; Wherein, the For aircraft of interest The probability that the data link relative distance information is fault-free, For aircraft of interest Is a cooperative fault detection threshold; step 9.5), for facilitating unified comparison, calculating a fault detection limit corresponding to the cooperative fault detection statistics of the target aircraft in step 9.3) : ; Wherein, the A cooperative fault detection threshold value; Step 9.6), comparing the cooperative fault detection statistics calculated in step 9.3) with the fault detection limit value calculated in step 9.5), and judging whether the data link relative ranging information of the target aircraft is faulty or not, if so And (5) indicating that the data link distance measurement data of the target aircraft has faults, otherwise, indicating that the target aircraft has no faults.
  8. 8. The method for detecting and identifying a fault in a navigation system group based on a common mode combination of co-navigation information according to claim 7, wherein the specific steps of the step 10) are as follows: Step 10.1), according to the judging result in the step 9), if faults occur, carrying out identification and isolation processing on the faults, and constructing fault identification statistics by utilizing least square collaborative residual vectors as follows: ; Wherein, the Representing a target aircraft Synergistic residual vector first The number of elements to be added to the composition, Is a target aircraft Weighting matrix First, the Line 1 The elements of the column are arranged such that, Representing a target aircraft Synergistic residual sensitivity matrix Is the first of (2) Line 1 Elements of a column; step 10.2), in the whole collaborative navigation system, since the number of auxiliary aircrafts is And the number of visible satellites of the target aircraft is Obtaining Identification statistics based on a given false alarm rate The false alarm rate of each identification statistic is The formula for calculating the limit value of the fault recognition of the data chain is as follows: ; Wherein, the Representing a target aircraft The probability that the identification statistic of (c) is greater than the fault detection threshold, For aircraft of interest Is a threshold value for data link failure identification, Probability density function of standard normal distribution; step 10.3) based on the detection threshold calculated in step 10.2) by comparing each of the identification statistics And a recognition threshold Is used for judging the size of the target aircraft To which auxiliary aircraft the ranging data fails if Target aircraft To auxiliary aircraft The navigation system further isolates the fault of the data link ranging, otherwise, the fault of the data link ranging is indicated.

Description

Navigation system group fault detection and identification method based on collaborative navigation information common mode combination Technical Field The invention relates to the technical field of measurement and navigation, in particular to a navigation system group fault detection and identification method based on collaborative navigation information common mode combination. Background The collaborative navigation technology utilizes the relative measurement information obtained by the clustered aircrafts in the communication and interaction processes to carry out auxiliary positioning, thereby improving the integral navigation precision of the system. The global satellite navigation technology is most widely applied, and for a collaborative navigation system, the satellite navigation technology is utilized to obtain relatively high positioning precision, and meanwhile, according to actual application scenes, relative measurement information of auxiliary sensors such as a data chain, inertial navigation, visual navigation and the like is introduced, so that the positioning performance and reliability of the whole navigation system are improved. However, in addition to positioning accuracy, attention should be paid to the integrity of the collaborative navigation system to ensure accuracy and robustness of the navigation system. For example, when a clustered aircraft performs a mission, a sensor may fail, and if the clustered aircraft fails, the navigation system cannot alarm in time, which may cause serious consequences. In a navigation system, for fault detection of satellites, receiver Autonomous Integrity Monitoring (RAIM) is a technology built into a GNSS receiver for monitoring the pseudorange residuals of satellites to determine if a satellite fault has occurred. Although it has the advantages of fast alarm capability and independence from external devices, the fault detection sensitivity will be severely degraded in complex environments such as a limited number of available satellites, signal multipath or non-line of sight (NLOS), etc. Disclosure of Invention The invention aims to solve the technical problem of providing a navigation system group fault detection and identification method for collaborative navigation information common mode combination aiming at the defects related to the background technology. The invention adopts the following technical scheme for solving the technical problems: The navigation system group fault detection and identification method based on collaborative navigation information common mode combination comprises the following steps: Step 1), each aircraft in a cluster system acquires satellite pseudo-range observation values by using a GNSS receiver, acquires relative distance information between the aircraft by using a data chain as an auxiliary sensor, and establishes an observation equation according to the satellite pseudo-range observation values and the relative distance observation values; The number of the clustered aircrafts is M, wherein one aircraft is a target aircraft v, v is {1,2, & gt, and when M } is adopted, the other aircraft are auxiliary aircrafts k, k is {1,2, & gt, and M }, and the visible satellite numbers of the target aircraft v and the auxiliary aircrafts k are n v and n k respectively; Step 1.1), satellite pseudo-range observation values of all aircrafts in a cluster system are calculated, and a pseudo-range observation equation of an auxiliary aircraft k is as follows: Wherein, the To assist aircraft k in currently all visible satellites to the firstPseudo-range measurements for a visible satellite, j e {1,2,..n k },To assist aircraft k to satelliteΗ is the speed of light, δt u is the clock error of the GNSS device on board the aircraft k, ε ρ is the pseudo-range noise including satellite clock error, ionosphere, troposphere delay and errors due to signal multipath and non-line of sight; step 1.2), calculating a relative distance observation equation from the target aircraft v to the auxiliary aircraft k as follows: Wherein, the For the relative distance measurement from the target aircraft v to the auxiliary aircraft k, d k is the true value of the relative distance from the target aircraft v to the auxiliary aircraft k, δt r is the clock difference of the data link system on board the target aircraft v, δt s is the clock difference of the data link system on board the auxiliary aircraft k, and ε d is the measurement noise of the data link system Step 2), in a cluster network, information interaction is carried out among all aircrafts, the respective observed quantity is shared, and each aircraft unit carries out linearization processing on an observation equation of the aircraft unit and calculates corresponding pseudo-range residual errors and relative distance residual errors; step 3), each aircraft constructs respective observation matrixes according to the visible satellites and the distance information to other aircraft, estab