Optimization Design of Trans-Earth Injection Using Two Step Solution Technique

Paper number

IAC-09.A3.2INT.5

Author

Dr. Hong-xin Shen, National University of Defense Technology, China

Coauthor

Dr. Hai-yang Li, National University of Defense Technology, China

Year

2009

Abstract

This paper discussed the optimal trans-Earth injection(TEI) with the objective to meet the final constrains at Earth 
interface(EI) which is desired for precision landing. For this trans-Earth mission, the gravitational effects of the 
Moon, Earth, and Sun constitute a 4-body problem. Since the EI parameters are sensitive to the TEI maneuvers, the 
success of this optimal process is strongly dependent on the availability of suitable startup arcs, so the 
appropriate initial transfer trajectory characteristics must be chosen. A two step solution technique is presented 
here. The first step is to make a good initial guess prior to optimizer. To improve the precision of the initial 
guess, we employed patched multi-conic method(PMCM) instead of patched conic method, moreover, unlike the 
conventional PMCM, the Earth oblateness effect which has great impact on EI parametres is considered by Vinti's 
method. Subsequently, a numerical search basing on the initial result produces the near accurate solution for this 
problem, the differential-corrector method is uesd to obtain the perturbed solution for the resulting optimal 
problem. STK is employed to test and improve the accuracy of the solution. It is shown that the new PMCM method can
provide a good initial guess effectively and efficiently and this approach ensures the optimal trajectory from LLO
to a specific Earth interface is obtained.

Abstract document

IAC-09.A3.2INT.5.pdf

Manuscript document

IAC-09.A3.2INT.5.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.