Onboard Guidance for Reusable Rockets: Aerodynamic Descent and Powered Landing

This paper describes a novel general on-board guidance strategy which can be applied toboth the aerodynamically-controlled descent and the powered landing phase of reusable rockets.The proposed guidance method is based on sequential convex optimization applied to a Cartesianrepresentation of the equations of motion. The contributions are an exploitation of convexand non-convex contributions, which are processed separately to maximize the computationalefficiency of the approach, the inclusion of highly nonlinear terms represented by aerodynamicaccelerations, a complete reformulation of the problem based on the use of Euler angle rates ascontrol means, an improved transcription based on the use of a generalized hp pseudospectralmethod, and a dedicated formulation of the aerodynamic guidance problem for reusable rockets.The problem is solved for a 40 kN-class reusable rocket. Results show that the proposedtechnique is a very effective methodology able to satisfy all the constraints acting on the system,and can be potentially employed online to solve the entire descent phase of reusable rockets inreal-time

Apollo 11 Reloaded: Optimization-based Trajectory Reconstruction

This paper wants to be a tribute to the Apollo 11 mission, that celebrated its 50th anniversary in 2019. By using modern methods based on numerical optimization we reconstruct critical phases of the original mission, and more specifically the ascent of the Saturn V, the translunar injection maneuver that allowed the crew to leave the Earth’s sphere of influence, and the Moon landing sequence, starting from the powered descent initiation. Results were computed by employing pseudospectral methods, and show good agreement with the original post-flight reports released by NASA after the successful completion of the mission

Ascent and Descent Guidance of Multistage Rockets via Pseudospectral Methods

This paper illustrates the trajectory modeling of multistage rockets for both ascent anddescent phases. The computation of solutions is performed by coupling a multiphase optimal-control problem formulation with a transcription performed via Radau pseudospectral meth-ods. Four examples inspired by both historical rockets like the Saturn V, and modern reusablelaunch systems like the Falcon 9 demonstrate the feasibility of the proposed modeling approachfor the rapid prototyping of valid reference solutions

Onboard Trajectory Generation for Entry Vehicles via Adaptive Multivariate Pseudospectral Interpolation

harvest AIAA 2016-2115Astrodynamics & Space Mission