Autonomous low-thrust guidance: application to SMART-1 and BepiColombo.

Area of Science:

• Aerospace Engineering
• Astrodynamics
• Space Mission Design

Background:

• Optimum trajectory generation for low-thrust propulsion is well-established.
• However, effective guidance schemes to follow these trajectories are less explored.
• Existing methods, like the DeepSpace1 mission algorithm, offer a foundational approach.

Purpose of the Study:

• To develop and validate a generic guidance algorithm for interplanetary low-thrust trajectories.
• To enable optimization of guidance control vectors derived from any thrust profile.
• To assess the algorithm's performance, stability, and robustness for various space missions.

Main Methods:

• A novel method to transform arbitrary thrust profiles into a controllable thrust law using a finite set of control variables.
• Optimization of a control vector for guidance based on the transformed thrust law.
• Simulation-based performance comparison of the enhanced guidance schemes against established missions (SMART-1, BepiColombo).

Main Results:

• The enhanced guidance schemes demonstrate effective performance across different interplanetary missions.
• The algorithm's generic applicability is validated, independent of the trajectory optimization technique.
• Parametric analysis confirms the stability and robustness of the proposed guidance schemes.

Conclusions:

• The presented guidance method offers a versatile and robust solution for navigating low-thrust trajectories.
• The algorithm's adaptability makes it suitable for a wide range of interplanetary missions.
• Further analysis confirms the scheme's stability and sensitivity to key parameters.