Along with the increase of the number of failed satellites, plus space debris, year by year, it will take considerable manpower and resources if we rely just on ground surveillance and early warning. An alternative effective way would be to use autonomous long-range non-cooperative target relative navigation to solve this problem. For longrange non-cooperative targets, the stereo cameras or lidars that are commonly used would not be applicable. This paper studies a relative navigation method for long-range relative motion estimation of non-cooperative targets using only a monocular camera. Firstly, the paper provides the nonlinear relative orbit dynamics equations and then derives the discrete recursive form of the dynamics equations. An EKF filter is then designed to implement the relative navigation estimation. After that, the relative “locally weakly observability” theory for nonlinear systems is used to analyze the observability of monocular sequence images. The analysis results show that by relying only on monocular sequence images it has the possibility of deducing the relative navigation for long-range non-cooperative targets. Finally, numerical simulations show that the method given in this paper can achieve a complete estimation of the relative motion of longrange non-cooperative targets without conducting orbital maneuvers.

Rapid development of Chinese commercial launch vehicles brings new challenges under the traditional systems engineering (TSE) working method. A new model-based systems engineering (MBSE) working method was proposed for Smart Dragon 1 (SD-1), which is a low-cost commercial launch vehicle developed by the China Academy of Launch Vehicle Technology (CALT). Based on the characteristics of a commercial launch vehicle, the system model based on information cards was established. Through a problem-oriented working method, risk identification and management, the process of Card-MBSE was utilized and verified by the success of the maiden flight of SD-1. This paper introduces a new method and reference for the development of low-cost and high-reliability launch vehicles.