OPTIMAL LOW-THRUST TRANSFER USING VARIABLE BOUNDED THRUST

The problem of minimum-fuel time-fixed transfer and rendezvous using v ariable bounded thrust is presented based on the use of a set of non-s ingular orbit elements. The consideration of maximum and minimum bound s on the thrust magnitude with constant power is equivalent to constra ining the specific impulse of the propulsion system such that this par ticular variable is optimized during the transfer. The thrust vector o rientation is also optimized in order to minimize fuel consumption. Ex act non-linear dynamics for state vector propagation and constraint in equalities on the thrust magnitude are considered in the formulation o f this low-thrust transfer problem. An example of minimum-fuel time-fi xed rendezvous is shown and compared to the solution with constant thr ust obtained earlier to illustrate the derivations.