A method to evaluate the trajectory dynamics of low-thrust spacecraft is refined and applied to targeting and optimal control problems. The original method uses averaged variational equations for the osculating orbital elements with 14 Fourier coefficients of the thrust acceleration vector to estimate a spacecraft trajectory over many spiral orbits. The accuracy of this method is improved by correction of any offset of the averaged trajectory from the true trajectory due to non-trivial periodic components. Spacecraft targeting problems are then solved using the corrected averaged variational equations and a general cost function represented as a Fourier series. A method for reducing the cost of a transfer by selection of acceleration Fourier coefficients beyond the 14 that appear in the averaged equations is described.
展开▼
