Shape-Based Approximation Method for Low-Thrust Trajectory Optimization

Abstract

Mission design using low-thrust propulsion requires a method for approximating the spacecraft’s trajectory and its cost. This can be for the purpose of evaluating a large search space or for providing a suitable initial guess to be used with more-accurate trajectory optimizers that are more likely to converge when given an initial guess satisfying the equation of motion constraints and the terminal boundary conditions. A new low-thrust 3D shape-based approximation method is developed and tested on two sample problems that require interception and rendezvous trajectories. The method quickly locates near-optimal minimum fuel solutions for the examples presented.