Earlier this year I (successfully!) defended my dissertation titled “Design of Missed Thrust Resilient Trajectories Using Expected Thrust Fraction” and have now obtained my Doctorate of Philosophy. As, could have been expected, my dissertation was on Expected Thrust Fraction (Theory of Expected thrust fraction, an application to Mars Sample Return and Solar Sailing) Dissertation Abstract “Low-thrust…
Stuff Happens… In the tail end of 2021, SpaceX launched a commercial resupply mission to the ISS. That mission used Booster B1069, which landed successfully on the drone ship. Unfortunately, by the time it returned to port, something had happened, damaging most of the engines and likely requiring at least significant repairs. This led to…
Note: This post is adapted from my conference paper, which was presented at the 11th International ESA Conference on Guidance, Navigation & Control Systems. You can read the full paper here. Abstract – Measuring Resilience Of Autonomous Controllers To Missed Thrust Events On A Mars To Earth Trajectory As spacecraft adopt low-thrust electric propulsion to reduce propellant mass,…
Note: This post is adapted from my journal paper, which was accepted to Aerospace Science and Technology in Spring 2021. You can read the full paper here Abstract – Designing Trajectories Resilient to Missed Thrust Events Using Expected Thrust Fraction With the adoption of efficient low-thrust propulsion methods, the probability of a missed thrust event…
Note: This post is adapted from my conference paper, which was presented at the Astrodynamics Specialists Conference in Summer 2020. You can read the full paper here. Abstract – Designing Trajectories Resilient to Missed Thrust Events Using Expected Thrust Fraction With the adoption of efficient low-thrust propulsion methods, the probability of a missed thrust event occurring has…
Note: This post is adapted from my conference paper, that I presented at the Astrodynamics Specialists Conference in Summer 2020. You can read the full paper here. Abstract – Using Reinforcement Learning to Design Missed Thrust Resilient Trajectories From ion thrusters to solar sails, spacecraft continue to adopt new and more efficient forms of propulsion. As…
Note: This post is adapted from my journal paper, which was accepted to Acta Astronautica in Spring 2020. You can read the full paper here Abstract – Neural Network Optimal Control in Astrodynamics While high-efficiency propulsion techniques are enabling new mission concepts in deep space exploration, their limited thrust capabilities necessitate long thrusting arcs and…
Earlier last week I was talking to one of my undergrads about the different subspecialties in astrodynamics and I’ve decided to distill that conversation into the following blogpost. Trajectory Design The best-known sub-specialty of astrodynamics, and the one that I’m in, is trajectory design. We answer questions like how do we get from Earth to…
Introduction NOTE: This is a very graphics-heavy post and may take some time to load. Lagrange points are those points in the three-body system where the tug of gravity from the two primary bodies cancel out and any spacecraft stays in the same relative position with the two primary bodies. If you are in the rotating…
Intro Last year we had a 2 part series on how to land on the moon using a suicide burn. There, the condition was that we could only turn on the engine once, and it had to be fully throttled. But most landers can control their thrust, so in this post we’re going to go…
