Reentry trajectory optimization based on a multistage pseudospectral method.

Area of Science:

• Aerospace Engineering
• Computational Fluid Dynamics
• Guidance, Navigation, and Control

Background:

• The pseudospectral method is effective for reentry trajectory optimization.
• Traditional pseudospectral methods are computationally intensive due to numerous discretization points.
• Autonomous and adaptive reentry guidance requires efficient trajectory optimization.

Purpose of the Study:

• To develop a multistage trajectory control strategy for hypersonic vehicle reentry.
• To address the computational limitations of traditional pseudospectral methods.
• To enable autonomous and adaptive reentry guidance capable of handling unexpected situations.

Main Methods:

• A multistage trajectory control strategy based on the pseudospectral method.
• Decomposition of the problem into trajectory estimation and trajectory refining subproblems.
• Generation of a specified range of trajectory with state transitions in each stage.

Main Results:

• The proposed method generates optimal trajectory sequences for a full glide trajectory.
• The strategy effectively incorporates geographic constraints relevant to actual flight.
• Numerical examples demonstrate feasibility for free-space, target transition, and threat avoidance flights.

Conclusions:

• The multistage pseudospectral method offers an efficient solution for reentry trajectory optimization.
• The strategy enhances adaptability for unexpected reentry flight scenarios.
• This approach supports autonomous and adaptive reentry guidance systems.