University of Illinois Urbana-Champaign

Robust trajectory and guidance optimization for guided powered descent and landing

Calkins, Grace Elizabeth

This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.

Permalink

https://hdl.handle.net/2142/120427

Description

Title
Robust trajectory and guidance optimization for guided powered descent and landing
Author(s)
Calkins, Grace Elizabeth
Issue Date
2023-05-01
Director of Research (if dissertation) or Advisor (if thesis)
Putnam, Zachary R
Department of Study
Aerospace Engineering
Discipline
Aerospace Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
M.S.
Degree Level
Thesis
Keyword(s)
  • trajectory optimization
  • GNC
  • EDL
  • aerospace
  • safe and precise landing
  • navigation
Abstract
A robust trajectory optimization approach for guidance algorithm gain and target vector selection for powered descent and landing is developed. A genetic algorithm is used to determine optimal guidance algorithm parameters that minimize the impact of environment, navigation, vehicle property uncertainty. Vehicle state uncertainties are computed rapidly using linear covariance analysis techniques. When implemented in the guidance algorithm, the optimal gains and target vectors shape a trajectory that has more favorable conditions for a given navigation sensor suite. As a demonstration of this method, the optimal guidance parameters are found for a multi-phase trajectory from powered descent initiation to touchdown for a robotic lunar landing mission. Optimal guidance parameters are found for different optimization variable sets, sensor suite compositions and qualities, and with objective functions to minimize variability in propellant usage or terminal position. Multi-objective optimization showing the tradeoff between terminal position uncertainty and total propellant usage is presented for varying sensor suite fidelities and sensor suite compositions. Results show that the optimal guidance algorithm parameters for a given trajectory differ based on the sensor suite and result in performance improvements over the baseline in propellant usage and terminal accuracy. Improvements of up to a 20% reduction in landed footprint size and up to a 5% reduction in total propellant usage can be seen when using robust trajectory optimization, and operating with a lower quality sensor suite becomes viable when optimal guidance parameters are used.
Graduation Semester
2023-05
Type of Resource
Thesis
Copyright and License Information
Copyright 2023 Grace Calkins

Owning Collections

Graduate Dissertations and Theses at Illinois PRIMARY
Graduate Theses and Dissertations at Illinois