.ccd / Ins Compound Terminal Guidance Information Alignment Technology

Composite terminal guidance technology is the technique that uses several kinds of sensors to guide the weapons in final homing stage. In the CCD/INS Composite Terminal Guidance System (CTGS), there are two sensors: CCD camera and IMU, which correspond to two immeasurable coordinate benchmarks - camera coordinate system and IMU coordinate system. Coordinate alignment is the process to determine the relative relations of these two coordinate systems, then convert all the information into a common one. Coordinate alignment is a chief problem in CCD/INS CTGS, and its performance directly determines the accuracy of the guided weapons.This thesis mainly dwells on the technique relative to the coordinate alignment and the design of the experiment.Camera calibration is one of the important content of the thesis. Chapter 3 put emphases on this part including image processing, calibration method and experiments. Corner detection is the main task of the image processing in camera calibration. According to the characteristic of the planar model, a new method for corner detection, based on image skeleton, is proposed in this thesis. The feasibility of the method is proved by the real data experiment results. Hough transform is used to detect lines and has been improved to be more accurate in the application. On the camera calibration, a new calibration method based on planar vanishing points is proposed. Computer simulation, error analysis and real data are used to test the proposed method and the result proves the validity of it. At last, 3D reconstruction is used to verify the accuracy of the method.In chapter 4, a method of coordinate alignment based on relative motion is discussed at length and the corresponding experiment is designed. Monte Carlo method is used to analyze the system error. A two axis turntable and a CCD camera are used to realize the system experiment and two relative motions are needed to get all the needful parameters. Then, a self-alignment method is discussed to get the relative orientation of two coordinate systems, which is supposed to get a similar result with the relative motion method so as to verify the feasibility of it. Integrative real data experiment is carried out and indicates that all the methods proposed and the designs of the whole system are effective and feasible.