Powered Descent Trajectory Optimization of Chandrayaan-3 using Radau Collocation and Controllable Sets

TL;DR

This paper introduces a trajectory optimization method for Chandrayaan-3's lunar landing using Radau collocation and controllable sets, improving robustness and efficiency in mission planning.

Contribution

It presents a novel optimization framework combining pseudospectral Radau collocation with controllability-based waypoint refinement for lunar descent.

Findings

Enhanced robustness of the descent trajectory against perturbations.

Quantified trade-off between fuel consumption and robustness.

Improved trajectory design methodology for lunar landings.

Abstract

India achieved a significant milestone on August $23^{\text{rd}}$ 2023, becoming the fourth country to accomplish a soft landing on the Moon. This paper presents the powered descent trajectory design for the Chandrayaan-3 mission. The optimization framework is based on pseudospectral Radau collocation, and controllability-based waypoint refinement is employed to further enhance the robustness of the trajectory against state and control perturbations. Furthermore, the trade-off between fuel consumption and robustness is explicitly quantified, providing insights into the practical considerations of mission planning.