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Minimum-Fuel Time-Fixed Rendezvous Using Constant Low Thrust*

Jean Albert Kechichian**

Abstract

The problem of minimum-fuel time-fixed rendezvous using a set ot nonsingular orbit elements is presented. Constant thrust is applied during the powered phases of the trajectory with the thrust vector orientation optimized to minimize fuel expenditure. The selection of mean longitude as the fast orbit element results in a simpler dynamic system not involving time explicitly. The Hamiltonian is therefore constant throughout the powered and unpowered phases of the trajectory with simpler boundary conditions to satisfy. Exact trajectories are generated by simultaneously integrating a system of 14 differential equations for the state and adjoint variables involving the orbit elements and the spacecraft mass.
*This work was supported by the U.S. Air Force Space and Missle Systems Center under Contract No. F-04701-88-C-0089

**Engineering Specialist, Flight Dynamics Department, The Aerospace Corporation, MS M4-942 P.O. Box 92957 Los Angeles California 90009.  Member AAS