CN-121980768-A - Modeling and correcting method and system for static pointing error of horizontal telescope

CN121980768ACN 121980768 ACN121980768 ACN 121980768ACN-121980768-A

Abstract

The invention belongs to the technical field of astronomical observation equipment, and particularly relates to a modeling and correcting method and system for static pointing errors of a horizontal telescope. The method comprises the steps of S1, establishing a horizontal telescope static pointing model, analyzing shafting error factors of the telescope, S2, deriving a telescope shafting static pointing error compensation model based on the static pointing model, S3, substituting experimental data, utilizing least square fitting data to determine each undetermined coefficient of the compensation model, and S4, utilizing the compensation model to correct the warp axis and weft axis static pointing errors of the telescope. The invention has the characteristics of improving the observation precision, improving the calibration efficiency and having wide applicability.

Inventors

LI HAOZHEN
HU MIAO
WANG SHAOKUN
NING WANGSHI
LI PENG

Assignees

杭州电子科技大学

Dates

Publication Date: 20260505
Application Date: 20251230

Claims (7)

1. The modeling and correcting method for the static pointing error of the horizontal telescope is characterized by comprising the following steps of; s1, establishing a static pointing model of a horizontal telescope, and analyzing shafting error factors of the telescope; S2, deducing a telescope shafting static pointing error compensation model based on the static pointing model; S3, substituting experimental data, and utilizing least square fitting data to determine each undetermined coefficient of the compensation model; S4, correcting the static pointing errors of the warp axis and the weft axis of the telescope by using the compensation model.
2. The method for modeling and correcting static pointing error of horizontal telescope according to claim 1, wherein step S1 comprises the steps of: s11, the mechanical structure of the horizontal telescope consists of a warp beam and a weft beam, and a static pointing model is correspondingly built as follows: (1); (2); Wherein, the The rotation angle of the warp beam is represented, Is the weft axis rotation angle; for the warp beam rotation angle error, The latitude axis rotation angle errors ;a 1 、a 2 、a 3 、a 4 、a 5 、a 5 、a 6 、a 7 、b 1 、b 2 、b 3 、b 4 、b 5 are all static pointing model parameters of the horizontal telescope.
3. The method for modeling and correcting static pointing error of horizontal telescope according to claim 2, wherein in step S1, the factors of the telescope axis error include: Zero error, which is an error caused by the offset of the initial calibration point of the telescope; the error of code disk installation is the geometric deviation generated in the process of encoder or sensor installation; Warp and weft axis non-vertical errors, i.e. errors caused by incomplete vertical of warp and weft axes during machining or assembly; The error of the angle between the visual axis of the telescope and the horizontal plane; Beam pointing error, i.e. error generated by the fact that the beam is not fully aligned with the north-south direction; Beam tilt error-pointing deviation due to beam tilt.
4. A method for modeling and correcting static pointing error of a horizontal telescope according to claim 3, wherein step S2 comprises the steps of: S21, establishing a horizontal three-dimensional coordinate system, wherein the horizontal three-dimensional coordinate system takes the installation position of the telescope as an origin, respectively defines the directions of three axes, is vertical to the ground plane, and forms a coordinate system based on the ground plane, and in the coordinate system, a warp beam of the horizontal telescope is parallel to the ground plane and points to the north-south direction, and a weft beam is vertical to the warp beam and points to the east-west direction; s22, analyzing the formula (1) and the formula (2), and deducing a shafting static pointing error compensation model, wherein the shafting static pointing error compensation model is specifically as follows: When (when) When the horizontal telescope warp beam shafting error compensation model is expressed as: (3); (4); And (3) finishing to obtain: (5); (6); When (when) When the horizontal telescope weft axis system error compensation model is expressed as: (7); (8); And (3) finishing to obtain: (9) (10) A 1 、A 2 、A 3 、B 1 、B 2 、B 3 、C 1 、C 2 、C 3 、D 1 、D 2 、D 3 are the undetermined coefficients after the error compensation model is integrated, respectively.
5. The method for modeling and correcting static pointing error of horizontal telescope according to claim 4, wherein step S3 comprises the steps of: s31, acquiring pointing error data through actual observation: in the experiment, at least 50 stars distributed along the warp axis and the weft axis are selected from the HIP star table as observation targets, and the theoretical position of each star is recorded respectively ) And the actual observation position ) Taking the deviation of the actual observation position and the theoretical position of the star as input data to respectively calculate the static pointing error of the shafting : (11) S32, obtaining static pointing error of the shafting Substituting the static pointing error data into model equations (5), (6), (9) and (10), and taking the error data as the input of least square fitting; S33, fitting the error data by using a least square method: The sum of squares of the errors is minimized by solving the linear equations of equations (5), (6), (9) and (10) or using a numerical optimization algorithm to obtain the optimal value of the undetermined coefficient A 1 、A 2 、A 3 、B 1 、B 2 、B 3 、C 1 、C 2 、C 3 、D 1 、D 2 、D 3 .
6. The method for modeling and correcting static pointing error of horizontal telescope according to claim 5, wherein step S4 comprises the steps of: s41, setting , And The static pointing precision of the warp beam L, the weft beam B and the whole system is calculated by adopting a standard deviation formula, and the method is specifically as follows: (12); (13); (14); Wherein n is the number of stars in the observation experiment; Is the first The observation points; And (3) calculating the warp beam pointing precision and the weft beam pointing precision before and after correction of the compensation model by using the formulas (12) - (14).
7. A modeling and correction system for static pointing error of a horizontal telescope, for implementing the modeling and correction method for static pointing error of a horizontal telescope according to any one of claims 1 to 6, wherein the modeling and correction system for static pointing error of a horizontal telescope comprises: the model building module is used for building a static pointing model of the horizontal telescope and analyzing shafting error factors of the telescope; the model deriving module is used for deriving a telescope shafting static pointing error compensation model based on the static pointing model; the undetermined coefficient determining module is used for substituting experimental data and utilizing least square fitting data to determine each undetermined coefficient of the compensation model; and the correction module is used for correcting the static pointing errors of the warp beam and the weft beam of the telescope by using the compensation model.

Description

Modeling and correcting method and system for static pointing error of horizontal telescope Technical Field The invention belongs to the technical field of astronomical observation equipment, and particularly relates to a modeling and correcting method and system for static pointing errors of a horizontal telescope. Background Since the 90 s of the last century, various countries have accelerated the development and emission of low-orbit satellites. The low orbit satellite is an important field of modern satellite technology development due to the characteristics of low communication delay, relatively low transmitting cost and the like. Up to now, the number of global low-orbit satellites exceeds 4000, accounting for more than 80% of all satellites, and only in 2020 and 2021, 1122 and 1664 low-orbit satellites are transmitted globally, respectively. This shows that over time, the number of low orbit satellites on earth will continue to grow rapidly. The rapid discovery and accurate tracking of low-orbit satellites have become a technical problem to be solved in astronomical observation and space exploration of various countries. At present, detection and tracking of foundation targets mainly depend on radar technology and photoelectric telescope technology. Compared with radar technology, the detection capability of the photoelectric telescope is inversely proportional to the action distance, and the photoelectric telescope has higher detection efficiency and lower energy consumption in target detection and tracking. According to the different mechanical structures, the photoelectric telescope is mainly divided into three types of horizon type, equatorial type and horizontal type. The horizontal telescope has no observation blind area in the zenith area, can cover any observation position in the longitude and latitude axis range, is widely focused in recent years, and has obvious advantages in the task of accurately tracking a low-orbit satellite. However, various errors are inevitably generated during the manufacturing, installation and use of the horizontal telescope. These errors can cause the telescope's pointing to deviate from the theoretical target, thereby reducing the accuracy of the observation, collectively referred to as static pointing errors. In practice, axis errors are the most common and more significant type of error. The mechanical structure of the horizontal telescope consists of a warp beam and a weft beam, which are in theory perpendicular to each other and parallel to the ground plane, wherein the warp beam is required to be precisely directed in the north-south direction, and the weft beam is required to be precisely directed in the east-west direction. However, due to the superposition of the errors, the static pointing accuracy of the horizontal telescope often cannot meet the requirement of high-accuracy observation. Aiming at the problems, the invention establishes a static pointing error compensation model according to the static pointing model of the horizontal telescope by comprehensively considering various error factors such as shafting errors, code disc errors, zero errors and the like, and corrects the shafting errors of a certain bi-horizontal telescope so as to improve the shafting static pointing precision of the certain bi-horizontal telescope. Disclosure of Invention The invention aims to solve the problem that the existing horizontal telescope is easy to generate static pointing error in the manufacturing, mounting and using processes in the prior art, and provides a modeling and correcting method and system for the static pointing error of the horizontal telescope, which can improve the observation precision, the calibration efficiency and the wide applicability. In order to achieve the aim of the invention, the invention adopts the following technical scheme: The modeling and correcting method of the static pointing error of the horizontal telescope comprises the following steps of; s1, establishing a static pointing model of a horizontal telescope, and analyzing shafting error factors of the telescope; S2, deducing a telescope shafting static pointing error compensation model based on the static pointing model; S3, substituting experimental data, and utilizing least square fitting data to determine each undetermined coefficient of the compensation model; S4, correcting the static pointing errors of the warp axis and the weft axis of the telescope by using the compensation model. Preferably, the step S1 includes the steps of: s11, the mechanical structure of the horizontal telescope consists of a warp beam and a weft beam, and a static pointing model is correspondingly built as follows: (1); (2); Wherein, the The rotation angle of the warp beam is represented,Is the weft axis rotation angle; for the warp beam rotation angle error, The latitude axis rotation angle errors ;a1、a2、a3、a4、a5、a5、a6、a7、b1、b2、b3、b4、b5 are all static pointing model parameters of the horizon