A Study on Optimal Low Thrust Orbit Transfers
Fumiaki Imado Central Research Laboratory Mitsubishi Electric Corporation
Abstract
A study on orbit transfers with a low thrust is presented. First, fuel consumptions are
compared in orbit transfers from 200A;m altitude circular orbit to higher circular orbits,
by ideal impulsive Hohmann transfer, optimal control and conventional Hohman transfer
approximation with a finite thrust. In the optimal control, control histories are obtained
by solving nonlinear two point boundary value problems. The result shows the fuel
losses with the optimal control are almost neglected in compareing to that of ideal Hohman
transfers, while some fuel losses are resulted in Hohman transfers approximation with a
finite thrust. In these transfers with a finite thrust, some minimum time intervals are
required. The relation between the time intervals and uneliminated eccentricities is
studied. Two real time trajectory compensation algorithms employing effect coefficients
and a linear quadratic regulator are also presented.