AAS 96-100

Approximate Solutions for Lunar Trajectory and Vehicle Optimization Using Electric PropULsion

C. A. Kluever and K. Chang, University of Missouri - Columbia/Kansas City

Abstract

An approximate method for computing minimum-fuel and maximum-payload lunar trajectories using electric propulsion has been developed. The planar Earth-moon transfer is obtained by patching together two powered escape and capture spirals with a numerically-integrated translunar coasting trajectory. Curve-fits of universal low-thrust trajectory solutions are used to replace the powered escape and capture spirals. The complete trajectory optimization problem is reduced to a small number of design variables and solutions are readily obtained by using sequential quadratic programming. Several minimum-fuel and maximum-payload trajectories are obtained for a wide range of thrust-to-weight ratios and the performance of the approximate method exhibits a very close match with published exact optimal solutions.