Maneuvering target tracking method based on angle measurement information

Abstract

The invention relates to a maneuvering target tracking method based on angle measurement information. The method comprises the following steps: acquiring azimuth angle measurement information and pitch angle measurement information of x continuous and accumulated sampling periods; calculating the estimated values of the motion direction angles of the projections of the target on the NOE plane and the UON plane by using the azimuth angle measurement information and the pitch angle measurement information of the x sampling periods; solving a predicted value of azimuth angle information and a predicted value of pitch angle information in the next sampling period by using the estimated value of the motion direction angle and the azimuth angle and pitch angle measurement information in the recent multiple sampling periods; and adjusting the direction of the optical equipment based on the predicted value of the azimuth angle information and the predicted value of the pitch angle information to complete target tracking measurement. The method has the remarkable advantages of being high in prediction precision, simple in calculation method, low in system configuration requirement and the like, and can be used for guiding design, development and use of ground optical measurement equipment.

Description

Technical Field

[0001] The present invention relates to the field of spacecraft measurement and control technology, and in particular to a maneuvering target tracking method based on angle measurement information. Background Art

[0002] In space launch missions, ballistic measurement equipment is needed to measure the rocket throughout the entire process. The equipment responsible for ballistic measurement tasks includes radio equipment and optical equipment. The measurement elements include azimuth, pitch angle, radial distance, etc. At present, some optical equipment only has angle measurement function. The premise of ballistic measurement is that the equipment continuously and stably tracks the rocket. The premise of stable tracking is that the equipment predicts the position of the rocket at the next moment based on the previous measured data, and controls the pointing direction of the equipment antenna or telescope to move to the predicted direction. When the rocket enters the antenna beam or optical field of view, the rocket is measured ballistically.

[0003] For radio equipment, since its measurement elements include azimuth, pitch angle, radial distance, etc., it can solve the rocket's ballistic information in real time, and use the solved position and speed to predict the position at the next moment, which makes it easy to achieve continuous tracking measurement. For optical equipment without ranging function, it is impossible to completely solve the rocket's ballistic information using only the acquired azimuth and pitch angle. The current common practice is to approximate the characteristics of the rocket's azimuth and pitch angle changing with time as a linear function or a quadratic function, and use this approximate characteristic to make predictions, and then make continuous measurements.

[0004] In fact, although the actual flight process of the rocket can be approximated as a short-term uniform speed or uniform acceleration motion in three-dimensional space, if the position information in the three-dimensional space is mapped to the azimuth and pitch angle information in the two-dimensional space, it no longer conforms to the linear change characteristics. The current commonly used practices have certain system errors, especially when the pitch angle is high, the system error is larger.

[0005] Therefore, it is necessary to design an accurate trajectory prediction and tracking method based on angle measurement information. Summary of the invention

[0006] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a maneuvering target tracking method based on angle measurement information. On the premise of approximating the rocket flight process as a short-time uniform linear motion, the motion characteristics and angle measurement information are comprehensively utilized to losslessly map the target position change characteristics in three-dimensional space into the target angle change characteristics in two-dimensional space, thereby realizing a method for accurate angle prediction, and providing the basic process of measurement, solution, prediction and tracking by optical equipment.

[0007] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is:

[0008] The present invention provides a method for tracking a maneuvering target based on angle measurement information, comprising the following steps:

[0009] Step S1, obtaining azimuth angle measurement information and elevation angle measurement information accumulated continuously for x sampling periods;

[0010] Step S2, using the azimuth angle measurement information and the elevation angle measurement information of x sampling periods, calculate the estimated value of the motion direction angle of the projection of the target on the NOE plane and the UON plane;

[0011] Step S3, using the estimated value of the motion direction angle and the azimuth angle measurement information and the elevation angle measurement information of the most recent multiple sampling periods, solving the predicted value of the azimuth angle information and the predicted value of the elevation angle information of the next sampling period;

[0012] Step S4: Based on the predicted value of the azimuth angle information and the predicted value of the elevation angle information, the direction of the optical device is adjusted to complete the target tracking measurement.

[0013] According to a technical solution of the present invention, step S1 specifically includes:

[0014] The ground optical measurement equipment is used to continuously accumulate the azimuth and elevation angle measurement information of x sampling periods, including the azimuth A i , A i+1 , A i+2 , A i+3 , …A i+x-1 and pitch angle E i 、E i+1 、E i+2 、E i+3 ,…E i+x-1 .

[0015] According to a technical solution of the present invention, step S2 specifically includes:

[0016] Step S201, dividing the azimuth angle measurement information of x sampling periods into n combinations, using the motion trajectory characteristics of the target projection in the NOE plane related to the azimuth angle, solving the first motion direction angle of the target projection corresponding to the n combinations, and taking the average value as the estimated value of the first motion direction angle of the target projection;

[0017] Step S202: divide the pitch angle measurement information of x sampling periods into n combinations, use the motion trajectory characteristics of the target projection in the UON plane to solve the second motion direction angle of the target projection corresponding to the n combinations, and take the average value as the estimated value of the second motion direction angle of the target projection.

[0018] According to a technical solution of the present invention, step S3 specifically includes:

[0019] Step S301, using the estimated value of the first motion direction angle of the target projection and the azimuth measurement information of the latest n-1 sampling periods, predicting the azimuth information of the next sampling period;

[0020] Step S302: using the estimated value of the second motion direction angle of the target projection and the azimuth angle measurement information and the pitch angle measurement information of the latest n-1 sampling periods, predict the projection of the pitch angle information of the next sampling period and convert it into the predicted value of the pitch angle information.

[0021] According to a technical solution of the present invention, in step S2, the pitch angle measurement information is projected onto the UON plane to obtain the projection of the pitch angle measurement information, and then the projection of the pitch angle measurement information is used to calculate the estimated value of the second motion direction angle.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The invention discloses a method for tracking a maneuvering target based on angle measurement information, which has the characteristics of high precision, simple calculation process and low requirement on system configuration.

[0024] According to the solution of the embodiments of the present invention, the maneuvering target tracking method based on angle measurement information conforms to the actual flight characteristics of the target in three-dimensional space. The predicted target motion direction angle and the angle information of the next sampling period basically eliminate the system error. At the same time, the random error of the estimated value of the motion direction angle is effectively corrected by averaging. The prediction result is close to the actual position of the target with high precision, which can further ensure the stability and reliability of continuous tracking measurement of the equipment, and at the same time, the requirement for the field of view size of the optical equipment is relatively low.

[0025] Furthermore, the calculation process of the present invention mainly involves trigonometric function calculation, and the steps are clear, and the calculation process is simple and easy to implement.

[0026] In addition, the present invention does not require a rocket to install a cooperative target, and can complete the measurement task relying only on ground equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic diagram schematically shows a rocket flight process and an optical device observation process in a three-dimensional space in an embodiment of the present invention;

[0029] Figure 2A schematic diagram schematically shows the relationship between the azimuth angle A measured by the optical device and the motion trajectory of the NOE plane projection in an embodiment of the present invention;

[0030] Figure 3 The flowchart schematically shows the method for tracking a maneuvering target based on angle measurement information in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The description of the embodiments of this specification should be combined with the corresponding drawings, which should be considered as part of the complete specification. In the drawings, the shape or thickness of the embodiments may be enlarged and indicated for simplification or convenience. Furthermore, the parts of each structure in the drawings will be described separately. It is worth noting that the elements not shown in the drawings or not described in words are in a form known to ordinary technicians in the relevant technical field.

[0032] The description of the embodiments herein and any reference to directions and orientations are only for the convenience of description and are not to be construed as any limitation on the scope of protection of the present invention. The following description of the preferred embodiments may involve combinations of features, which may exist independently or in combination, and the present invention is not particularly limited to the preferred embodiments. The scope of the present invention is defined by the claims.

[0033] like Figures 1 to 3 As shown in FIG. 1 , a maneuvering target tracking method based on angle measurement information of the present invention approximates the rocket (target) flight process as a short-term motion direction that remains unchanged and the same distance in the same time. Then, the rocket flight process and the optical device observation process in three-dimensional space are as follows: Figure 1 As shown, Figure 1 In the equation, l is the distance the rocket moves per unit time. The trajectory of the rocket is projected onto the NOE plane (east-sky) and the UON plane (east-north), respectively. The projected trajectory still conforms to the characteristics of short-term uniform linear motion. The relationship between the azimuth angle A measured by the optical device and the trajectory of the NOE plane projection is as follows: Figure 2 As shown in the figure, l A is the projection of l on the NOE plane, m i is the projection of the radial distance of the target relative to the measuring device on the NOE plane; the relationship between the pitch angle E measured by the optical device and the motion trajectory of the UON plane projection can be referred to Figure 2 , I will not go into details later.

[0034] The invention discloses a method for tracking a maneuverable target based on angle measurement information, and its overall process includes: deploying optical measurement equipment; accumulating initial measurement data; and continuously performing prediction, tracking and measurement.

[0035] Among them, the deployed optical measurement equipment needs to have at least azimuth and pitch angle measurement functions. Specifically, for space launch missions, one or more sets of optical measurement equipment are deployed to be responsible for the rocket's exterior ballistic measurement tasks. The equipment has azimuth and pitch angle measurement functions.

[0036] The control center sends guidance data to the optical device to achieve initial capture and tracking of the device, and accumulates angle measurement information for at least 5 sampling moments, thereby completing the accumulation of initial measurement data.

[0037] By using the maneuvering target tracking method based on angle measurement information proposed by the present invention, the estimated values ​​of the motion direction angle of the rocket projection in the NOE plane and the UON plane are solved respectively, and the estimated value of the direction angle and the angle measurement information of the last two sampling cycles are comprehensively used to predict the azimuth and pitch angle information of the next sampling cycle, and the direction of the optical device is adjusted accordingly. After the rocket enters the field of view, the measured angle information is obtained. At this time, the prediction, tracking, and measurement of one sampling cycle are completed, and the above process is repeated to continuously complete the rocket tracking and measurement task.

[0038] Aiming at the scenario where ground equipment of space launch missions continuously tracks and measures rockets, and considering the characteristic that optical measurement equipment can only obtain angle measurement information but cannot completely solve the rocket trajectory, the present invention approximates the rocket flight process as a short-time uniform linear motion, studies the comprehensive utilization of the motion characteristics and angle measurement information, and deduces through rigorous formulas to losslessly map the target position change characteristics in three-dimensional space into the target angle change characteristics in two-dimensional space, thereby achieving accurate prediction of the angle information.

[0039] The method for tracking a maneuvering target based on angle measurement information of the present invention comprises the following specific steps:

[0040] Step S1, obtaining azimuth angle measurement information and elevation angle measurement information accumulated continuously for x sampling periods, specifically includes:

[0041] The ground optical measurement equipment is used to continuously accumulate the azimuth and elevation angle measurement information of x sampling periods, including the azimuth A i , A i+1 , A i+2 , A i+3 , …A i+x-1 and pitch angle E i 、E i+1 、E i+2 、E i+3 ,…E i+x-1 ;

[0042] Step S2, using the azimuth angle measurement information and the pitch angle measurement information of x sampling periods, calculate the estimated value of the motion direction angle of the projection of the target on the NOE plane and the UON plane, specifically including:

[0043] Step S201, dividing the azimuth angle measurement information of x sampling periods into n combinations, using the motion trajectory characteristics of the target projection in the NOE plane related to the azimuth angle, solving the first motion direction angle of the target projection corresponding to the n combinations, and taking the average value as the estimated value of the first motion direction angle of the target projection;

[0044] Step S202: divide the pitch angle measurement information of x sampling periods into n combinations, use the motion trajectory characteristics of the target projection in the UON plane to solve the second motion direction angle of the target projection corresponding to the n combinations, and take the average value as the estimated value of the second motion direction angle of the target projection;

[0045] Step S3, using the estimated value of the motion direction angle and the azimuth angle measurement information and the elevation angle measurement information of the most recent multiple sampling periods, solving the predicted value of the azimuth angle information and the predicted value of the elevation angle information of the next sampling period, specifically including:

[0046] Step S301, using the estimated value of the first motion direction angle of the target projection and the azimuth measurement information of the latest n-1 sampling periods, predicting the azimuth information of the next sampling period;

[0047] Step S302: using the estimated value of the second motion direction angle of the target projection and the azimuth angle measurement information and the pitch angle measurement information of the latest n-1 sampling periods, predict the projection of the pitch angle information of the next sampling period, and finally convert it into a predicted value of the pitch angle information;

[0048] In the step S2, the pitch angle measurement information is projected onto the UON plane to obtain the projection of the pitch angle measurement information, and then the projection of the pitch angle measurement information is used to calculate the estimated value of the second motion direction angle.

[0049] The following is a detailed description with specific embodiments.

[0050] like Figure 3 As shown, first, the azimuth and elevation angles are accumulated continuously for 5 sampling periods;

[0051] The estimated value of the motion direction angle of the rocket projection in the NOE plane is solved according to the azimuth measurement information. The specific process is: the azimuth measurement information of 5 sampling periods is divided into 3 combinations {A i , A i+1 , A i+2}、{A i+1 , A i+2 , A i+3}、{A i+2 , A i+3 , A i+4}, using the characteristics of the projected motion trajectory that conforms to short-term uniform linear motion, solve the motion direction angle α of the rocket projection in the NOE plane i , α i+1 , α i+2 , to solve α i For example, the formula is:

[0052]

[0053] On this basis, take α i , α i+1 , α i+2 The average value α′ is used as the estimated value of the motion direction angle of the rocket projection in the NOE plane, which is the estimated value of the first motion direction angle.

[0054] Using the calculated direction angle estimate α′ and the azimuth angle measurement information A of the last two sampling periods i+3 , A i+4 Predict the azimuth information A' of the next sampling period i+5 , the specific formula is:

[0055]

[0056] Referring to the methods of the previous two steps, solve the estimated value of the motion direction angle of the rocket projection in the UON plane and predict the pitch angle information of the next sampling period. The specific process is:

[0057] Assume that the moving direction angle of the rocket projection in the UON plane is β i , refer to the previous two steps, solve the estimated value β′ of the second motion direction angle of the rocket projection in the UON plane, and predict the pitch angle information E′ of the next sampling period i+5 When solving, please note that you should first calculate the measured value of the pitch angle E i Projection to the UON plane (obtain E i投影 ) and then participate in the calculation of β′. The projection conversion process is expressed as:

[0058] cosA i tanE i投影 =tanE i

[0059] Solve for the second motion direction angle β i The process is expressed as:

[0060]

[0061] On this basis, take β i , β i+1 , β i+2The average value β′ is used as the estimated value of the motion direction angle of the rocket projection in the UON plane, that is, the estimated value of the second motion direction angle;

[0062] Prediction E′ i+5投影 and calculate E′ i+5 The formula is expressed as:

[0063]

[0064] Finally, the direction of the optical equipment is adjusted according to the predicted pitch and azimuth angles. After the rocket enters the field of view, the target is captured and the azimuth and pitch angle measurements are completed. It is also determined whether the tracking and measurement task is completed. If so, the task ends; if not, the tracking and measurement continues.

[0065] The present invention provides a maneuvering target tracking method based on angle measurement information, which conforms to the actual flight characteristics of the target in three-dimensional space. The predicted target motion direction angle and the angle information of the next sampling period basically eliminate the system error. At the same time, the averaging method is adopted to effectively correct the random error of the estimated value of the motion direction angle. The prediction result is close to the actual position of the target with high precision, which can further ensure the stability and reliability of the continuous tracking measurement of the equipment, and at the same time, the requirement for the field of view size of the optical equipment is relatively low.

[0066] Furthermore, the calculation process of the present invention mainly involves trigonometric function calculation, and the steps are clear, and the calculation process is simple and easy to implement.

[0067] In addition, the present invention does not require a rocket to install a cooperative target, and can complete the measurement task relying only on ground equipment.

[0068] The serial numbers of the above-mentioned steps involved in the method of the present invention do not mean the order of execution of the method. The execution order of each step should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation mode of the present invention.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for tracking a maneuvering target based on angle measurement information, characterized in that: The following steps are involved: Step S1, obtaining azimuth angle measurement information and elevation angle measurement information accumulated continuously for x sampling periods; Step S2, using the azimuth angle measurement information and the elevation angle measurement information of x sampling periods, calculate the estimated value of the motion direction angle of the projection of the target on the NOE plane and the UON plane; Step S3, using the estimated value of the motion direction angle and the azimuth angle measurement information and the elevation angle measurement information of the most recent multiple sampling periods, solving the predicted value of the azimuth angle information and the predicted value of the elevation angle information of the next sampling period; Step S4: Based on the predicted value of the azimuth angle information and the predicted value of the elevation angle information, the direction of the optical device is adjusted to complete the target tracking measurement.

2. The method according to claim 1, characterized in that The step S1 specifically includes: The ground optical measurement equipment is used to continuously accumulate the azimuth and elevation angle measurement information of x sampling periods, including the azimuth A i , A i+1 , A i+2 , A i+3 , …A i+x-1 and pitch angle E i 、E i+1 、E i+2 、E i+3 ,…E i+x-1 .

3. The method according to claim 1, characterized in that The step S2 specifically includes: Step S201, dividing the azimuth angle measurement information of x sampling periods into n combinations, using the motion trajectory characteristics of the target projection in the NOE plane related to the azimuth angle, solving the first motion direction angle of the target projection corresponding to the n combinations, and taking the average value as the estimated value of the first motion direction angle of the target projection; Step S202: divide the pitch angle measurement information of x sampling periods into n combinations, use the motion trajectory characteristics of the target projected in the UON plane to solve the second motion direction angle of the target projection corresponding to the n combinations, and take the average value as the estimated value of the second motion direction angle of the target projection.

4. The method according to claim 1, characterized in that: The step S3 specifically includes: Step S301, using the estimated value of the first motion direction angle of the target projection and the azimuth measurement information of the latest n-1 sampling periods, predicting the azimuth information of the next sampling period; Step S302: using the estimated value of the second motion direction angle of the target projection and the azimuth angle measurement information and pitch angle measurement information of the latest n-1 sampling periods, predict the projection of the pitch angle information of the next sampling period in the UON plane and convert it into the predicted value of the pitch angle information.

5. The method according to claim 3, characterized in that: In step S202, the pitch angle measurement information is projected onto the UON plane to obtain a projection of the pitch angle measurement information, and then the projection of the pitch angle measurement information is used to calculate an estimated value of the second motion direction angle.

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