TW524986B - Passive ranging/tracking processing method - Google Patents

Abstract

A passive ranging/tracking processing method provides information from passive sensors and associated tracking control devices and GPS/IMU integrated navigation system, so as to produce three dimensional position and velocity information of a target. The passive ranging/tracking processing method includes the procedure of producing two or more sets of direction measurements of a target with respect to a carrier, such as sets of elevation and azimuth angles, from two or more synchronized sets of passive sensors and associated tracking control devices, installed on different locations of the carrier, computing the range vector measurement of the target with respect to the carrier using the two or more sets of direction measurements, and filtering the range vector measurement to estimate the three-dimensional position and velocity information of the target.

Description

524986 V. Description of the invention α) This application is a formal application, and its related pre-application application number is 60/199, 052. The application date is April 22, 2000. Description of the invention This invention is supported by the U.S. Government. The project contract number is DAAH10-00-C-0028. It is provided by Aviation Applied Missile Command (Aviation Applied Technology Di rectorate, US Army Aviation and Missile Command, FortEustis). , VA23604-5577). The U.S. government has certain rights in this invention. The invention relates to a method for target ranging / tracking, and more specifically to a passive ranging / tracking method, in which the direction measurement comes from two or more laterally arranged passive sensors and the related sensors on the carrier. The tracking control device integrates navigation with GPS / IMU (Global Positioning System / Inertial Measurement Unit). The data from the system is processed to provide three-dimensional position and velocity information of the moving target. 〇 Currently, more and more real-time autonomous aircraft are required in a large application area, such as industry, industry, health care, military, space, and underwater. The main performance of a real-time autonomous body depends on the guidance and navigation processing and control structure. '' Port navigation focuses on the optimal integration of information from multiple navigation sensors, such as GPS receivers, IMUs, and so on. The optimal matching guidance rate produces the required trajectory shape, based on the position information of the autonomous body from the navigation subsystem and the target ^

Page 5 524986 V. Description of the invention (2) The target position information from the tracking system, so as to satisfy the optimal criterion at different stages of the motion trajectory. Target acquisition and tracking depend on increasing autonomy requirements in system design. Navigational bodies often need to be sensitive to their environment and tracking targets, which is essential for their navigation. Target state estimation needs to provide or predict accurate target states from some or noisy sensor data. In general, the traditional method of generating a distance measurement between the population and the target is to use an active sensor, such as a radio radar or sodar, or a laser ranging sensor. The working principle of the active ranging tracking sensor is based on measuring the time between the active sensor's transmitted signal and the target's reflected signal. The fluctuating and vertical method has significant advantages over the active and vertical method. Unlike radar, lasers, and other active tracking controls, passive sensors do not send any form of energy outward. They only receive the energy emitted by the target and then convert it into measurement data. This feature makes the passive tracking method an ideal technique for reconnaissance and surveillance applications, because it can detect targets but hide itself from external targets, it does not send signals. However, in general, the passive tracking method cannot measure the distance between the target and the sensor because it is not based on the signal > reflection principle. The passive sensor device only measures the direction of the target relative to the overall space. Therefore, under the conditions of uncertain target, poor dynamic model, interference, nonlinearity, and time-varying parameters, it is a great challenge to estimate the high-precision 3D position and distance of a target from an isolated passive sensor. Summary of the invention The main purpose of the present invention is to provide a passive ranging and tracking method, which can provide three-dimensional position and velocity information of a moving target.

524986 V. Description of the invention (3) Information of sensors and related tracking control devices and GPS / IMΙ integrated navigation system. Another object of the present invention is to provide a passive ranging tracking method, in which the pointing measurement of a moving target comes from two or more passive sensors synchronized in the lateral layout, and is used to determine the ranging measurement in a triangulation method. Ranging measurements are further filtered to provide 3D position and velocity information of moving targets.

Yet another object of the present invention is to provide a passive ranging tracking method, in which a pair of moving target's pointing measurements are from two passive image sensors with multiple side-by-side synchronized layouts, which are used to determine the ranging measurement using a triangular method. Ranging measurements are further filtered to provide 3D position and velocity information for moving targets. Another object of the present invention is to provide a passive ranging and tracking method, in which position, speed and attitude information from a GPSIMU navigation system integrated on a slave is combined to provide high-precision carrier position and attitude information to facilitate passive ranging. Tracking calculations. Another object of the present invention is to provide a passive ranging tracking method, in which the least square method is used to construct a passive ranging tracking algorithm to obtain some form of optimal estimation.

Another object of the present invention is to provide a passive ranging tracking method, in which an optimization method is used to construct a passive ranging tracking algorithm to obtain some form of optimal estimation. Another object of the present invention is to provide a passive ranging tracking method in which a non-linear Kalman filter is used to achieve an efficient, digitally convergent, high-precision passive ranging tracking calculation. In order to achieve the above objective, the present invention provides an implementation on a carrier

Page 7 524986 V. The passive ranging tracking method of the invention description (4), comprising the steps of: (a) generating two or more sets of measurements of the direction of the target relative to the carrier, such as a set of heights of the target And azimuth from two or more synchronized passive sensors through related tracking control devices, wherein the passive sensors are installed at different positions on the carrier; (b) generating navigation data for the carrier, including position, Speed, and attitude data, using the onboard navigation system; (c) calculating the target ranging vector measurement, with respect to the carrier, using the two or more sets of direction measurements; (d) extracting the target's The three-dimensional position and velocity information is measured during the period by using the target ranging vector. Explanation of drawing numbers: 1-Passive sensor array 4-Target ranging vector calculation 2-11, 12, 13-Passive sensor 6-Target position and speed estimator 7-GPS / IMU integrated navigation system 21, 22, 23-Tracking control Detailed description of the preferred scheme of the device The passive ranging and tracking method of the present invention provides a solution for obtaining the three-dimensional position and velocity of the target by using only the passive sensors on board. The navigation data on the GPS / IMU integrated navigation system is processed to obtain a passive ranging tracking solution.

524986 V. Description of the invention (5) The most common target tracking measurement consists of distance, distance change rate, azimuth, or altitude angle. In the present invention, the ranging vector measurement is first obtained from the output of a passive sensor array and associated tracking control device. Then, the coordinates of the specific positions of the three targets are extracted. The ranging vector measurement contains the orientation and distance information of the target relative to the carrier.

Referring to the first figure, each of the passive sensors 1 1, 1 2, 1 3 ... of the passive sensor array 1 receives the energy or signal emitted by the target, and generates a target direction measurement. Under the control of each tracking control device 2 1, 2 2, 2 3 of the tracking control device array 2, the passive sensors 1 1, 1 2, 1 3 · · · can keep pointing to the target space, so they have the ability Gives precise target orientation information. In order to isolate the maneuvering movement of the carrier and keep track of the target, each passive sensor 1 1, 1 2, 1 3 ... is usually installed on a two-degree-of-freedom observation platform of the corresponding tracking control device 21, 22, 23 ... It is further stabilized by a gyro-equipped control system.

For example, each tracking control device 21, 2, 2, 2, 3 ... can include an encoder, which is mounted on the axis of two gimbals, and outputs the accurate angular position of the passive sensor relative to the coordinate system of the carrier body. However, in the calculation of the geographic location of the target, the position of the passive sensor relative to the navigation coordinate system is required, so the carrier attitude must be known, and it must be combined with the bracket angle to obtain the angular position of the passive sensor relative to the navigation coordinate system. A target ranging vector is calculated 4. The navigation coordinate system can be the northeast sky coordinate system, the northeast land coordinate system, or the northwest sky coordinate system. Requires a GPS / IMU integrated navigation system 7 to provide attitude-accurate positioning

Page 9 524986 V. Description of the invention (6) Position and attitude through a target position and velocity estimator 6. Referring to the first graph and the second graph, a passive ranging tracking method for tracking a target running on a carrier includes the following steps: (1) Generate at least a first and a second group of direction measurements relative to the carrier, such as an altitude and azimuth group , From two or more passive sensor groups 1 1, 1 2, 1 3. · · Via related tracking control devices 2 1, 22, 23. · Among them passive sensors 11, 12, 13 ... Different positions of the carrier; (2) generating the navigation data of the carrier, including position, velocity, and attitude data, using the on-board navigation system; (3) calculating the target's target ranging vector measurement relative to the carrier, using two or more For multi-directional measurement, the target vector calculation 4 is shown in the first figure; and (4) the target three-dimensional position and velocity information is extracted. In the current period, the target vector measurement is used to pass the target position and velocity estimator 6, One picture. The preferred in-flight navigation system is the GPS / IMU integrated navigation system 7, which can provide long-term, high-precision carrier navigation data. In most applications, the two passive sensors 11, 1 2 of the present invention are sufficient to solve the passive ranging tracking problem. A preferred implementation of the present invention, in which two passive sensors 1 1 and 1 2 are applied is disclosed below. Note that the present invention is not limited to the case where the objective sensors 1 1, 12 are applied. As a preferred implementation, step (1) further includes the following steps: (1 · 1) Generate a first set of target orientation measurements relative to the carrier, such as height and azimuth, using the first passive sensor 1 1 through the first tracking control

Page 10 524986 V. Description of the invention (7) Control device 2 1; and (1.2) Generate a second set of target direction measurements with respect to the carrier, such as altitude and azimuth, using the second passive sensor 12 through the first A tracking control device 22; referring to the third step, step (3) further includes the following steps: (3 · 1) forming a hypothetical first target-sensor vector d 1 representing the direction between the target and the first passive sensor 11 The measurement is expressed in the first passive sensor coordinate system (xl, yl, zl), using the height and azimuth measurement of the target from the output of the first passive sensor 11, and the first An unknown distance

(3.2) Form a hypothetical second target-sensor vector d2, which represents the direction measurement between the target and the second passive sensor 12, and represents the second passive sensor coordinate system (x2, y2, z2). The output of the sensor 12 measures the height and azimuth of the target, and the second unknown distance between the target and the second passive sensor 12; (3.3) transforms the hypothetical first target-sensor vector dl from the first Passive sensor coordinate system (X 1, y 1, Z 1) to the carrier navigation coordinate system, using navigation data from GPS / IMU integrated navigation system 7;

(3.4) Convert the hypothetical second target-sensor vector d2 from the second passive sensor coordinate system (x 2, y 2, z 2) to the carrier navigation coordinate system, and use the navigation data from the GPS / IMU integrated navigation system 7 ; (3 · 5) Calculate the first passive sensor position vector rl, indicating that in the local navigation system, the first passive sensor position information L1 in the carrier coordinate system (Xb, Yb, Xb) is used, and From GPS / IMU Integrated Navigation System 7

Page 11 524986 V. Description of the invention (8) Navigation data; (3.6) Calculate the second passive propeller position vector r2, which is used in the local navigation coordinate system and used in the carrier coordinate system (Xb, Yb, Xb). The second passive sensor position information L2 and the navigation data from the GPS / IM integrated navigation system 7; (3 · 7) forming a first hypothetical target vector (d 1 + L 1), which is represented in the navigation coordinate system by A target-sensor vector d 1 and a first passive sensor position vector L 1 are added;

(3 · 8) forming a second hypothetical target vector (d 2 + L 2), which means that in the navigation coordinate system, by adding the second target-sensor vector d 2 and the first passive sensor position vector L 2; (3 · 9) Find the first unknown distance and the first unknown distance, and use the first hypothesized target vector and the second hypothesized target vector; (3. 10) Form the first target vector, and insert the first unknown distance into the first hypothesized target (3.11) forming a second target vector by inserting a second unknown distance into the second hypothetical target vector; (3 · 1 2) forming a ranging vector to measure r, using the first target vector and the second target vector. As a preferred implementation, step (3 · 9) further includes the following steps ··

(3. 9.A1) form a vector equation, and by difference between the first target vector and the second target vector; and (3.9.A2) find the first unknown distance and the second unknown distance, and solve the vector equation.

Page 12 524986 V. Description of the invention (9) Each of the passive sensors 1 i and 12 and the target in the carrier body coordinate system (Xb, Yb, Yz) can determine a straight line in three-dimensional space. Under ideal conditions, the intersection of these two lines is the location of the ranging target. Referring to the third figure, as described above, the positions of the two passive sensors 1 i, 12 are represented by (Xi, Yi, Zi) and (x2, y2, z2) in the navigation coordinate system, respectively. The first and second passive sensor position vectors are represented by M and 1 ^ 2. The two measured target directions are represented by the unit vectors 1 i and 12. The target direction obtained from the passive sensor device can be expressed by two angles: the height angle and the azimuth angle α, relative to the carrier coordinate system. Therefore, the target direction from each sensor device 11, 12 can be represented by a unit vector, i = l, 2.

-cosβ {cosa ,. cos β (sin a / -sin β (Assuming the target position is represented by the vector r in the carrier coordinate system. y (2)

The assumed target positions determined by the two passive sensors can be expressed respectively as r = L! + (1¾ 11 (3)

Page 13 524986 V. Description of the invention (ίο) r = L2 + d212 (4) where the variable seven or (12 is the unknown distance between the passive sensor and the target. The intersection of the two lines can be determined by the following equation d \ l \ -= L2 — Li = Δγ〇 (5) Written as a matrix in the form of ith, right. The energy d L and the fixed straight dl of the energetic solution can be confirmed. There are two things you can do to fix the cocoa. Confirm the process, so the two measures of 12 have a group test, only this distance is 11 but the test method is not based on the sense of the root, pass a process, the three-way question is determined to go beyond the distance, the test is Note 1 That is. Yes. Six> It should be misunderstood. It should be installed at a certain time. The straight line is worse than the root cause. The error is caused by two reasons. It must be missed. It is in the question. The actual position of the tracer and the distance between the standard and the actual distance are visual inspections of the actual source, but the source can be. The difference can be the most misunderstood, he calculated. The total value of the estimated piece is only wise and clever. It ’s bad. I think the mistake should be straightened out in the process.

^ -cos βχ cosa1 cos β2 cosa2 ^ Γί /, Ί X2 ~ X \ cos βχ sina, -cos /? 2 sina2 • cL = y2-y ^ <-sin / ?, sin A, LU2_ _Z2 ~ z \.

Page 14 524986 V. Description of the invention (11) In order to find the sum of ten, we use this criterion to find two points on the corresponding straight line to minimize the distance between the two straight lines. The distance between two straight lines depends on \, d2. If it is written as D, the distance can be s == = (Δχ-d2 cos β2 sin a2-\-dx cos / ?, sin a,) 2 + {/ Sy + d2 cos β2 cos a2 — dx cos / ?, cos ax) + (Δζ + sin /? 2-d 丨 sin /? 丨) 2

We can apply an optimization method to find ^, d2 to make S the smallest value. The minimum value of S is the shortest distance between two tracking straight lines. We can also use the least square method to solve equation (7), the result is the same as the minimization method described above. The solution can be expressed as a vector operation as follows:

= + [(Z 丨 / 2) «/ 2Ί where A = 1- [c〇sAc〇sAcx) S (a2-a〇 + SinASin /? 2] 2, and / 丨 岛, / 丨 / 2, / 2Δγ 〇

The dot product of two vectors is represented in the above equation. Note that unless the two straight lines are parallel (/ 3 1 = cold 2 and a 1 = a 2) we can always get the definite solutions 1 and (12 to optimize the position estimate. Substituting equation (8) into equations (3) and (4) ), Corresponding to d2 and 1 can get two

Page 15 524986 V. Description of the invention (12) Target ranging vectors. Taking the average of these two estimated vectors, we get r = ^ (r10 + r20 + + 44) (9) This is the solution to the target ranging problem. Ranging measurements are expressed as

In addition, we can get the estimated position of the target relative to the center of the carrier: (10) θν = a tan —- λΙ χ2 + y2 φν ^ tan y

Under ideal conditions, if the passive ranging tracking system has no errors, the minimized S will be zero. We can use the S value as a real-time check of the ranging error in a statistical sense. So step (3 · 9) further includes the following steps:

Page 16 524986 V. Description of the invention (13) (3.9. B1) Formula 1 for the distance parameter which represents the distance between two points of the first a-vector and the second S-vector using the first a-label And the second target vector; and (3.9. B2) find a set of the first unknown distance and the second unknown distance which minimize the value of the distance parameter to 0 or step (3 9). The step includes the following steps: (3 .9. C1) Form a vector formula by subtracting the first S-vector and the @ -th vector, and (3.9.C2) find the first set of unknown distances by solving the vector equation using the least square method? And the second unknown distance 0 as a preferred implementation solution, the step (3 • 1 2) further includes the following steps ... (3.1.2A) forming a ranging vector measurement 1 average the first a target vector and the second target Vector 〇 in When a section between the upper, from step (3) obtained in the ranging measurement noise vector big. Therefore, the position and speed extracted directly from the ranging measurement may be noisy. In order to improve the performance of the passive ranging tracking method of the present invention, refer to the second and fourth figures. Step (4) includes the following steps: (4 A) In each time period, the wave ranging is performed. For vector measurement, in the previous time period, a filter is used to estimate the 9 current position. 0 The wave filter of the present invention preferentially selects the Kalman filter. 0 The Kalman filter is an iterative method for estimating a dynamic system from a measurement that contains noise. A method for state variables0 The Kalman ferrule of the present invention uses ranging vector measurement and azimuth measurement

Page 17 524986 V. Description of the invention (14) Estimating the position of the current target relative to the carrier, and further predicting the future position of the target relative to the carrier. Kalman filtering algorithms include estimation algorithms and prediction algorithms. The dynamic model of tracking Kalman filter to establish the target is as follows:

Xk + 1 = FXk + GWk (12) where κ is the value of the state vector at time K. F is the system matrix, G is the input matrix, and Wk is the interference input vector. These quantities are defined as follows, where Qk is the interference matrix. X xu X χη y xAk y z-X6k _ z

F = 1 T 0 0 0 1 0 0 0 0 1 T 0 0 0 1 0 0 0 0 0 0 0 0 ~ 2 T Ο ο ο ο τ 1

Ο Ο ο ο 1 ο ο ο τ2 G = 2 Τ τ τ

νν

Page 18 524986 V. Description of the invention (15)

Qk = E [wkwTk] = qx 0 0 0 qy 0 0 0

Wk ~ N (0, Qk), where T is the sampling time. With reference to the fourth figure, the measurement of the Kalman filter is relative ranging, azimuth, and altitude angle ”± 2 + less 2+ 孑 (13)

ev ^ a ^ n-j = J = (14) such as + y (15)

Xk itself cannot be measured directly. The measurement equations (1 3), (1 4), and (1 5) can be further expressed as follows: z (k) = h (x (k)) + v (k) (16)

Where z (k) represents the discrete measurement at the kth sampling time tk, h (X) is a vector nonlinear function describing the relationship between the state vector and the measurement, and v (k) is the measurement noise with a variance of R (k). Because the measurement equation (1 6) is non-linear, an extended Karl

Page 19 524986 V. Description of the invention (16) The Mann filter is used to estimate the current position of the target and predict the target trajectory. Remember that the magic and P (k) are the estimates obtained by the extended Kalman filter and its variance error matrix. The optimal estimate of the current position of the target is obtained by the following two steps: Time propagation λ X (k // c -1) = FX (k / kl) Γ 1 7] P {k / ^ -1) = FP {k / / c-l) Fr + Qk_, measurement update When measurement Z (k) is available at time tk, A measurement update is performed to correct the estimate and its variance error matrix, using a standard discrete extended Kalman filter. The Jacobian matrix is defined as follows ... (19)

ah (x) | βχ | x = ⑽ “-1) The measurement update equation is:? j {k) = H (A:) P (A: / k-1) ΗΓ (/ 〇 + R (k) K ( k) = P_ (mr (k) n- \ k)

x (k) = x (k / / c -1) + K (k) [z (k)-h (x (k / k -1))] ^ ZU; P (/ c) = [I ~ K (k) R (k)]? (k / kl) where sand / bu 1) and P (k / kl) in equations (19) and (20) are square

Page 20 524986 V. Explanation of the invention (17) The solutions of (17) and (18) at time tk are just before z (k) is processed. Further, the measured updated outputs, i⑻ and p (k), provide initial conditions for (17) and (1 8) starting at time tk, just after z (k + 1) is processed. From (1 7) to (1 8) it is easy to see that irregular and intermittent situations are easy to handle. When there is no measurement, only the time is updated to produce an optimal estimate.

When sand is obtained at time tk), the target's track can be predicted, based on a given prediction time interval TP (21 X {k ^ Tplk) ^ FX {k) Generally, the prediction time TP is greater than the sampling time τ If τ = τ, the prediction of the target track can be included in the optimal estimated P calculation period (17) ~ (20) of the current position. In a preferred application of the present invention, the present invention can be a passive image sensor, which can be moved by a meal = an output image sequence. With reference to the fifth figure, the field α &lt; &gt; _ · Broken distance measurement tracking method includes the following steps: (1) In two passive image sensing tests, determine a pair of feature areas, where features The two synchronized image data 示 show the same-target in the two synchronized images; the heart; the two weights of the two different feature regions (3) use the two centers of gravity to calculate the two-dimensional gimbal measurement;

Page 21 524986 V. Description of the invention (18) (4) Use the onboard navigation computer to generate the navigation data of the carrier, including position, speed, and attitude data '; (5) Calculate the relative Target ranging vector measurement; (6) Use ranging vector measurement to 'extract the three-dimensional position and velocity information of the target in the current time period; after determining the center of gravity of the target in two images, it can extract relative to two passive image sensors The target orientation measurement is based on the knowledge of the relative position and orientation of the two passive image sensors and their internal parameters. As a preferred implementation, step (1) further includes the following steps. (1 A) Use a feature matching method to determine a pair of feature regions in two synchronized image data from two passive image sensors, where the feature Pair represents the same goal. There is a lot of literature on feature extraction and matching. One that has been successfully used in related applications, the complex feature matching and scene registration assumption is feature map matching. The feature map is represented by nodes and arcs, where each node corresponds to a derived image feature, and the arc represents the relationship between the nodes. For example, in the figure, a sensitive image consists of three targets (1, 2, 3), and contains specific spatial relationships and features (size, thickness, texture). From the three detected features, a feature map can be formed, as shown in the sixth figure. The nodes of the graph correspond to the three detected features, and the relationship between the nodes corresponds to their intersection angle or spatial relationship (top, right, etc.). Nodes also include features like size, thickness, and post-mortem.

524986 V. Description of the invention (19) The detected image features. The feature map represents the image derived from the passive image sensor; the three detected objects or image features 1, 2, and 3 are used to generate or synthesize a feature map representation; this scene map is then combined with the saved Refer to the figure for matching. The basic matching process requires generating a reference feature map, from available sources (for example, information about a manned machine), and synthesizing a sensitive feature map from a live sensor image. A special search algorithm is then applied to match these comparable representations. The matching and graph registration process is represented by the seventh graph. The output of the feature map matching algorithm is the largest common subgraph, which represents the degree of matching between the reference and sensitive data. The number of nodes and arcs in the output feature map can be used to evaluate the quality of the match. Based on the number of matched nodes and arcs, and the uniqueness of their corresponding features, the target model is used to form the reference map, which is input to (offline) The matching process; the live image obtained from the stereo sensor is synthesized into the detection feature map; finally, the two maps are represented (reference and detection map), and a special matching algorithm is used to match. The output is the largest common submap, representing the registration of reference and sensitive data. The feature map matching algorithm is shown in Figure 7, which uses branching and collection techniques to quickly match sensitive and reference maps. This process is mathematically a polynomial time algorithm. However, the features of nodes and arcs in the graph cover the search space, and the registration process can be performed in real time. Part of the time-consuming process is a feature extraction step in which pixel data is processed to detect targets in sensitive scenes. Features of applying this method include:

524986 V. Description of the invention (20) (i) Independent characteristic representation of the sensor, (ii) Permissible transmission change, '(iii) # ^ ^ Μ # (iv) When possible, combined with camera parameters, (v) means spacecraft Features, and (vi) prior experience in related procedures. The benefits of applying this method include: (i) the same technology can be applied to visible and infrared data, (i i) register wide-area data (i i i) constrained search to improve matching and reduce false alarms,

(iv) Improve search and matching accuracy, (v) Flexible integration of different reference data sources, and (vi) Low-risk methods. As another preferred implementation, another step (1) includes the following steps: (1 B. 1) detecting a moving target from at least two passive image sensors; and (1 B · 2) using a feature matching method, Among the two synchronized image data from two passive image sensors, a pair of feature regions is determined, where the feature pair represents the same target.

Alternatively, passive image sensors are visible light and infrared cameras. Therefore, the two passive image sensors can be externally synchronized to the precise timing signals of the GPS, so they can acquire images simultaneously, and the data in the two images are directly related.

Page 24 524986 V. Description of the invention (21) As a preferred implementation of the present invention, two passive sensors can be installed on two separate carriers to passively measure and track a target. Next, the passive ranging tracking method performed on two separate carriers includes the following steps: (1) Generate two or more target direction measurements with respect to at least the first and second carriers, such as the target's height and azimuth set , From two or more passive sensor groups, where the passive sensors are installed on the first and second carriers respectively through the relevant tracking control device; (2) generating navigation data for the first and second carriers, including position, speed, And attitude data using first and second carrier on-board navigation systems;

(3) Calculate the target ranging vector measurement of the target relative to the first and second carriers, using two or more orientation measurements, where the first and second carriers are connected by a data link; and (4) extract the target three-dimensionally The position and velocity information is measured in the current time period using the target ranging vector and is represented in the navigation coordinate system. As another option, it is obvious that the carrier may be in a stationary state, or two or more passive sensors may be directly on the ground, and according to the present invention, the carrier may be the earth. These passive sensors at different locations on the ground are connected through data links to achieve passive ranging tracking of targets.

524986 Brief description of the diagrams and diagrams The first diagram: a block diagram describing the passive ranging and tracking method according to the preferred implementation of the present invention. Second figure: A block diagram describing the steps of the passive ranging tracking method according to the preferred implementation of the present invention. Third figure: depicts the passive ranging geometry according to the preferred implementation of the invention described above. Fourth figure: depicts a passive tracking coordinate system according to the preferred implementation of the invention described above.

Fig. 5 is a block diagram illustrating the steps of the passive ranging tracking method of two passive image sensors according to the present invention. Sixth Figure: A related graphic representation depicting a preferred implementation of the invention described above. Figure 7: Describes the feature matching algorithm according to the above-mentioned preferred implementation of the present invention.

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Claims (1)

524986 6. Scope of patent application 1. A passive ranging / tracking method for tracking targets, including the following steps: (a) generating at least first and second sets of direction measurements relative to the carrier, from at least first and second Group of passive sensor groups, respectively, through at least a first and a second group of tracking control devices, wherein the two passive sensors are mounted on the carrier, and each of the passive sensors is controlled by the corresponding tracking control device to maintain Pointing at the target; (b) generating navigation data of the carrier, including position, velocity, and attitude data, using the onboard navigation system, (c) calculating a target ranging vector of the target relative to the carrier Measure, using the two sets of direction measurements; and (d) extract the three-dimensional position and velocity information of the target, and measure the target using the target vector in the current period. 2. The passive ranging / tracking method according to item 1 of the scope of the patent application, wherein each of the passive sensors receives energy or signals from the target to generate the first and second groups of the target Direction measurement, which is the height and azimuth of the target, respectively. 3. The passive ranging / tracking method according to item 2 of the scope of the patent application, wherein the ranging vector measurement includes information about the direction and distance of the target relative to the carrier. 4. The passive ranging / following method described in item 1 of the scope of the patent application, wherein each of the tracking control devices includes a two-degree-of-freedom observation platform, and each of the passive sensors is installed in the two-degree-of-freedom Observation platform to isolate the maneuver of the carrier and keep track of the target 524986 6. Scope of patent application. 5. The passive ranging / tracking method as described in item 4 of the scope of patent application, wherein each of said tracking control devices includes an encoder mounted on two support shafts, and outputs said passive sensor relative to said carrier The precise angular position of the system. 6. The passive ranging / tracking method according to item 3 of the scope of patent application, wherein each of said tracking control devices includes a two-degree-of-freedom observation platform, wherein each of said passive sensors is installed in said two-degree-of-freedom observation A platform to isolate the motorized movement of the carrier and keep track of the target. 7. The passive ranging / tracking method according to item 6 of the scope of patent application, wherein each of said tracking control devices includes an encoder mounted on two support shafts, and outputs said passive sensor relative to said carrier The precise angular position of the system. 8. The passive ranging / tracking method as described in item 1 or 3 of the scope of patent application, wherein step (a) further includes the following steps: (a. 1) generating a first set of said relative to said carrier Target direction measurement through the first tracking control device using the first passive sensor; and (a. 2) Generate a second set of target direction measurements relative to the carrier, use the second passive sensor, and control the device through the second tracking. 9. The passive ranging / tracking method as described in item 8 of the scope of patent application, wherein step (c) further includes the following steps: Page 28 524986 6. The scope of patent application (C · 1) forms a hypothetical first target-sensor vector, which represents the simple direction measurement of the target and the first passive sensor, and is expressed in the first passive sensor coordinate system. Use the height and azimuth measurements of the target from the output of the first passive sensor, and the first unknown distance between the target and the first passive sensor; (c · 2) forming a hypothetical A second target-sensor vector, which represents the direction measurement between the target and the second passive sensor, and represents the degree of latitude of the target using the output from the second passive sensor in the second passive sensor coordinate system Angle and azimuth measurements, and a second unknown distance between the target and the second passive sensor; (c · 3) transform the hypothetical first target-sensor vector from the first passive sensor coordinate To the carrier navigation coordinate system, using the navigation data from the GPS / IMU integrated navigation system, which provides the position and attitude information of the carrier; (c · 4), the conversion station Assume a second target-sensor vector from the second passive sensor coordinate system to the carrier navigation coordinate system, using the navigation data from the GPS / IMU integrated navigation system; (c · 5) calculating the first The passive sensor position vector represents the first navigation sensor position information in the carrier coordinate system in the local navigation coordinate system, and the navigation data from the GPS / IMU integrated navigation system; (c.6) Calculating the second passive sensor position vector, indicating that in the local navigation coordinate system, using the second gastric passive sensor position information in the carrier coordinate system, and integrating from the GPS / IMU Navigation system Page 29 524986 VI. Navigation data described in the scope of patent application; (c · 7) forming a first hypothetical target 'vector, which means that in the navigation coordinate system, the first target-sensor vector and the first passive Adding sensor position vectors; (c · 8) forming a second hypothetical target vector, which means that in a navigation coordinate system, by adding the second target-sensor vector and the first passive sensor position vector; (c · 9) Finding the first unknown distance and the first unknown distance, using the first hypothetical target vector and the second hypothetical target vector; (c. 10) forming the first target vector, Inserting the first unknown distance into the first hypothetical target vector; (c · 1 1) forming the second target vector by inserting the second unknown distance into the second hypothetical target vector; and (3 · 1 2) Forming a quantity of 湏 1J distance vector 湏 1J, using the first target vector and the second target vector. 10. The passive ranging / tracking method as described in item 9 of the scope of patent application, wherein step (c.9) further includes the following steps: (c. 9. A1) forming a vector equation, The target vector and the second target vector; and (c · 9 · A 2) obtain the first unknown distance and the second unknown distance, and through the solution vector equation, in the coordinate system of the carrier body The first passive sensor and the target in can determine a first straight line in a three-dimensional space, and the second passive sensor and the target in the carrier body coordinate system can determine a first straight line in a three-dimensional space. Two straight lines, so 524986 6. Scope of patent application The intersection of the first straight line and the second straight line is the position of the ranging target. 1 1. The passive ranging / tracking method as described in item 9 of the scope of the patent application, wherein step (c.9) further includes the following steps: (c. 9.. B 1) Form a formula for the distance parameter, which is expressed in A distance between two points of the first target vector and the second target vector, using the first target vector and the second target vector; and (c · 9 · B 2) find a set of the first unknown distance and the second unknown distance, which minimizes the value of the distance parameter. 12. The passive ranging / tracking method as described in item 9 of the scope of patent application, wherein step (c.9) further includes the following steps: (c. 9. C1) by combining the first target vector and the Subtract the second target vector to form a vector formula; and (c. 9. C 2) find a group of the first unknown distance and the second unknown distance by solving the vector equation using a least square method. 1 3 · Passive ranging / tracking method as described in item 9 of the scope of patent application, Step (d) further includes a step of filtering the ranging vector measurement in each time period, and in the current time period, using a filter to estimate the current position of the target. 14. The passive ranging / tracking method as described in item 10 of the scope of patent application, wherein step (d) further includes a step, in each time period, filtering Page 31 524986 VI. Scope of patent application Wave measurement of the ranging vector, in the current time period, a filter is used to estimate the current position of the target. 15. The passive ranging / tracking method as described in item 11 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 16. The passive ranging / tracking method according to item 12 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 17. The passive ranging / tracking method according to item 1 of the scope of patent application, wherein each of said passive sensors is a passive image sensor and step (a) includes the following steps: (a. 1) Among the two synchronized image data from the passive image sensors, at least first and second feature regions are determined, wherein the feature pairs represent the same target; (a. 2) in each of the synchronization maps In the image, calculate the center of gravity of each of the characteristic regions, (a · 3) use the center of gravity to calculate the direction measurement; 18. The passive ranging / tracking method according to item 17 of the scope of patent application, wherein in step (a · 1), the feature region is determined by a feature matching method. 19. The passive ranging / tracking method as described in item 18 of the scope of patent application, wherein the feature matching method is a feature map matching, where the feature map consists of Page 32 524986 VI. Scope of patent application Nodes and arcs, each of which corresponds to a derived image feature, and the arc represents the simple relationship of the nodes. 2 0. The passive ranging / tracking method as described in item 17 of the scope of patent application, further comprising the step of detecting the moving target person from the passive image sensor in two images before the step. 2 1. The passive ranging / tracking method as described in item 17 of the scope of patent application, wherein each of said passive image sensors may be a visible light or infrared camera, wherein said passive image sensors are externally synchronized with GPS Precise timing signals, so the visible or infrared cameras can acquire images simultaneously, and the data in the synchronized images are directly related. 2 2. The passive ranging / tracking method as described in item 17 of the scope of patent application, or item 20, or item 21, wherein step (c) further includes the following steps: (c · 1) forming a hypothesis The first target-sensor vector represents the direction measurement between the target and the first passive sensor, and represents the height of the target in the first passive sensor coordinate system using the output from the first passive sensor Angle and azimuth measurements, and the first unknown distance between the target and the first passive sensor; (c · 2) forming a hypothetical second target-sensor vector, representing the target and the second The direction measurement between the passive sensors indicates the height and azimuth measurement of the target using the output from the second passive sensor in the second passive sensor coordinate system, and the target and the second passive sensor A second unknown distance between; (c. 3) transforming the hypothetical first target-sensor vector from the first Page 33 524986 VI. Patent application scope-a passive sensor coordinate system to the carrier navigation coordinate system, using navigation data from the GPS / IMU integrated navigation system, which provides position and attitude information of the carrier; (c. 4) Transforming the hypothetical second target-sensor vector from the second passive sensor coordinate system to the carrier navigation coordinate system, using the navigation data from the GPS / IMU integrated navigation system; (c. 5) calculations The first passive sensor position vector indicates that in the local navigation coordinate system, the first passive sensor position information in the carrier coordinate system is used, and the navigation data from the GPS / IMU integrated navigation system (C. 6) calculating the second passive sensor position vector, indicating that in the local navigation coordinate system, using the second passive sensor position information in the carrier coordinate system, and integrating from the GPS / IMU The navigation data of the navigation system; (c · 7) forming a first hypothetical target vector, which is represented in a navigation coordinate system by Adding the sensor vector and the first passive sensor position vector; (c. 8) forming a second hypothetical target vector, which indicates that in the navigation coordinate system, the second target-sensor vector and the first passive Add sensor position vectors; (c · 9) find the first unknown distance and the first unknown distance, use the first hypothetical target vector and the second hypothetical target vector; (c.10) form Inserting the first unknown distance into the first hypothetical target vector for the first target vector; Page 34 524986 VI. The scope of patent application (c.ll) forms the second target vector, by inserting the second unknown distance into the second hypothetical target south; (c 金 .1 2) forming a measurement Distance vector measurement using the first target vector and the second target vector. 2 3. The passive ranging / tracking method described in item 22 of the scope of patent application, wherein step (c.9) further includes the following steps: (c. 9. A1) forming a vector equation, A target vector and the second target vector; and (c · 9 · A 2) obtain the first unknown distance and the second unknown distance, and use the solution vector equation to obtain coordinates in the carrier body. The first passive sensor and the target in the system can determine a first straight line in a three-dimensional space, and the second passive sensor and the target in the carrier body coordinate system can be determined in a three-dimensional space. The second straight line, so the intersection of the first straight line and the second straight line is the position of the ranging target. 2 4. The passive ranging / tracking method described in item 22 of the scope of patent application, wherein step (c.9) further includes the following steps: (c. 9. B1) Form a formula for the distance parameter, which is expressed in A distance between two points of the first target vector and the second target vector, using the first target vector and the second target vector; and (c · 9 · B 2) finding a group of the first An unknown distance and the second unknown distance, which minimize the value of the distance parameter. 25. The passive ranging / tracking method described in item 22 of the scope of patent application, wherein step (c · 9) further includes the following steps: 524986 6. The scope of patent application (C.9.C1) forms a vector formula by subtracting the first target vector and the second target vector; and (c. 9. C2) by using the least square method Solve the vector equation to find a group of the first unknown distance and the second unknown distance. 26. The passive ranging / tracking method as described in item 22 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 27. The passive ranging / tracking method as described in item 23 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 28. The passive ranging / tracking method according to item 24 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 2 9. — A passive ranging / tracking method for tracking a target, comprising the following steps: (a) generating at least first and second sets of direction measurements relative to at least the first and second carriers, from at least the first and A second group of passive sensors passes at least a first and a second group of tracking control devices, wherein the passive sensors are respectively mounted on the carrier, and each of the passive sensors is controlled by the corresponding heel control device, To keep pointing to the target; (b) generating navigation data for the first and second carriers, including bits 524986 VI. Patent application scope, speed, and attitude data, using the first and second carrier on-board navigation system; (C) Calculating the target ranging vector measurement of the target relative to the carrier, using the two Group or more direction measurements, wherein the first and second carriers are connected by a data link; and (d) extracting three-dimensional position and velocity information of the target, and using the target ranging vector to measure in the current period, Those in the navigation coordinate system. 30. The passive ranging / tracking method as described in item 29 of the scope of the patent application, wherein each of the passive sensors receives energy or signals from the target to generate the first and second of the target Group direction measurements, which are the height and azimuth of the target, respectively. 31. The passive ranging / tracking method according to item 30 of the scope of the patent application, wherein the ranging vector measurement includes information on the direction and distance of the target relative to the carrier. 32. The passive ranging / tracking method according to item 29 of the scope of patent application, wherein each of said tracking control devices includes a two-degree-of-freedom observation platform, and each of said passive sensors is mounted on said two-freedom Observe the platform in order to isolate the motorized movement of the carrier and keep track of the target. 33. The passive ranging / tracking method as described in item 32 of the scope of patent application, wherein each of said tracking control devices includes an encoder installed on two bracket shafts, and outputs said passive sensor relative to said The precise angular position of the carrier system. Page 37 524986 6. Application for patent scope 3 4. The passive ranging / tracking method described in item 31 of the scope of patent application, wherein each of said tracking control devices includes a two-degree-of-freedom observation platform, each of which The passive sensor is installed on the two-degree-of-freedom observation platform in order to isolate the motorized movement of the carrier and keep track of the target person. 35. The passive ranging / tracking method according to item 34 of the scope of patent application, wherein each of said tracking control devices includes an encoder installed on two bracket shafts, and outputs said passive sensor relative to said The precise angular position of the carrier system. 36. The passive ranging / tracking method as described in item 29 or item 31 of the scope of patent application, wherein step (a) further includes the following steps: (a · 1) A set of the target direction measurements, using the first passive sensor, through the first tracking control device; and (a. 2) generating a second set of the target direction measurements relative to the carrier, using the A second passive sensor is controlled by the second tracking device. 37. The passive ranging / tracking method according to item 36 of the scope of patent application, wherein step (c) further includes the following steps: (c · 1) forming a hypothetical first target-sensor vector, representing the direction measurement between the target and the first passive sensor, and representing the first passive sensor coordinate system, using the Output the height and azimuth measurements of the target and the first unknown distance between the target and the first passive sensor; Page 38 524986 6. The scope of patent application (c · 2) forms a hypothetical second target-sensor vector, which represents the measurement of the direction between the target and the second passive sensor, and is expressed in the second passive sensor coordinate system. Use the output from the second passive sensor to measure the height and azimuth of the target, and a second unknown distance between the target and the second passive sensor; (c, 3) transform the The hypothetical first target-sensor vector is from the first passive sensor coordinate system to the carrier navigation coordinate system, using navigation data from a GPS / IMU integrated navigation system, which provides position and attitude information of the carrier; (c · 4) converting the hypothetical second target-sensor vector from the second passive sensor coordinate system to the carrier navigation coordinate system, using the navigation data from the GPS / IMU integrated navigation system; ( c) 5) calculating the first passive sensor position vector, indicating that in the local navigation coordinate system, using the first passive sensor position information in the carrier coordinate system, and from the GPS / IMU integrated navigation system (C.6) calculating the second passive sensor position vector, indicating that in the local navigation coordinate system, using the second passive sensor position information in the carrier coordinate system, and from the The navigation data of the GPS / IMU integrated navigation system; (c · 7) forming a first hypothesized target vector, which means that in a navigation coordinate system, by adding the first target-sensor vector and the first passive sensor position vector; (c · 8) forming a second hypothesis Target vector, represented in the navigation coordinate system Page 39 524986 6. In the scope of patent application, by adding the second target-sensor vector and the first passive sensor position vector; (c. 9) obtaining the first unknown distance and the first An unknown distance, using the first hypothetical target vector and the second hypothetical target vector; (c · 10) forming the first target vector, and inserting the first unknown distance into the first hypothetical target Vector; (c · 1 1) forming the second target vector by inserting the second unknown distance into the second hypothetical target vector; (3 · 1 2) forming a ranging vector measurement using the first A target vector and the second target vector. 38. The passive ranging / tracking method described in item 37 of the scope of patent application, wherein step (c.9) further includes the following steps: (C.9.A1) forming a vector equation, A target vector and the second target vector; and (c · 9 · A 2) obtain the first unknown distance and the second unknown distance, and use the solution vector equation to obtain coordinates in the carrier body. The first passive sensor and the target in the system can determine a first straight line in a three-dimensional space, and the second passive sensor and the target in the carrier body coordinate system can be determined in a three-dimensional space. The second straight line, so the intersection of the first straight line and the second straight line is the position of the ranging target. 39. The passive ranging / tracking method as described in item 37 of the scope of patent application, wherein step (c.9) further includes the following steps: (C.9.B1) forming a formula for the distance parameter, which is expressed in Mentioned first 524986 VI. The scope of patent application: the distance between two points of a target vector and the second target vector, using the first target vector and the second target vector; and (c. 9 · B 2) to find a group The first unknown distance and the second unknown distance, which minimize the value of the distance parameter. 40. The passive ranging / tracking method as described in item 37 of the scope of patent application, wherein step (c.9) further includes the following steps: (c. 9. C1) by combining the first target vector with all Subtracting the second target vector to form a vector formula; and (c. 9. C 2) finding a set of the first unknown distance and the second unknown distance by solving the vector equation using a least squares method. . 41. The passive ranging / tracking method according to item 37 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a wavelet is used to estimate the current position of the target. 42. The passive ranging / tracking method as described in item 38 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 43. The passive ranging / tracking method according to item 39 of the scope of patent application, wherein step (d) further includes a step of filtering the ranging vector measurement at each time period, and at the current time On the segment, a filter is used to estimate the current position of the target. 4 4. The passive ranging / tracking method as described in item 40 of the scope of patent application, wherein step (d) further includes a step, in each time period, filtering Page 41 524986 VI. Scope of patent application For the measurement of the ranging vector, a filter is used to estimate the current position of the target in the current time period. 45. The passive ranging / tracking method as described in item 37 of the scope of patent application, wherein each of said passive sensors is a passive image sensor and step (a) includes the following steps ... (a. 1) in from At least two first and second feature regions are determined from two synchronized image data from at least two of the passive image sensors, wherein the feature pair represents the target; (a. 2) at each of the synchronizations In the image, calculate the center of gravity of each of the feature regions, and (a. 3) using the center of gravity to calculate the direction measurer. 46. The passive ranging / tracking method according to item 45 of the scope of patent application, wherein in step (a. 1), the feature region is determined by a feature matching method. 47. The passive ranging / tracking method according to item 46 of the scope of patent application, wherein the feature matching method is a feature map, where the feature map is represented by nodes and arcs, each of which is a node Corresponding to a derived image feature, an arc represents a relationship between the nodes. 48. The passive ranging / tracking method according to item 45 of the scope of patent application, further comprising the step of detecting the moving target person from the passive image sensor in two images before the step. 49. The passive ranging / tracking method as described in item 45 of the scope of patent application, wherein each of said passive image sensors may be a visible light or infrared camera, wherein said passive image sensors are externally synchronized with GPS Precise timing Page 524986 Page 43