A study was conducted to demonstrate low-thrust minimum-fuel optimization in the circular restricted three-body problem. The study solved the problem of geostationary transfer orbit (GTO)-to-halo transfer for the first time. This result was achieved with an indirect approach and constant specific impulse engine. Thrust-to-mass ratios in agreement with currently available technology were considered. Some effective techniques were applied to cope with problem complexity. These methods involved solving the minimum-fuel, minimum energy, and minimum-time problems, implementing energy-to-fuel homotopy, continuing the maximum thrust magnitude, and computing the analytic Jacobians

A comprehensive design procedure based on extremum seeking for minimum power demand formation è ight is presented, the é rst with performance guarantees. The procedure involves the design of a new wake robust formation hold autopilot and transformation of the closed-loop aircraft dynamics to a form in which a newly available rigorous design procedure for extremum seeking is applicable. The design procedure is applied to a formation of Lockheed C-5s, extending the use of maximum performance formation è ight to large transports. By the use of availableexperimental wake data of the C-5, a model of the aircraft in the wakeis developed that models aerodynamic interference as feedback nonlinearities. Thus, this work is also the é rst to attain stable extremum seeking for a plant with nonlinear feedback. Optimal formation è ight is attained by online minimization of an easily measurable objective, the pitch angle of the wingman.