I grew up in Indiana building rockets and hacking electronics. At Cornell University, I focused on designing, building, and the testing avionics and GNC subsystems of multiple spacecraft. I also ran the Cornell Maker Lab, an excellent resource for student prototype development. I was a PhD student at CU Boulder, where I got my master's degree in the Entry systems Design Lab under Robert D. Braun on developing algorithms for landing rockets.
This is an on-going personal project. Expect updates soon.
In early 2019, Sam Wishnek (Aerospace PhD Student at CU Boulder) and I implemented a Shazam system that utilizes a locality sensitive random hashing scheme for APPM5720: Randomized Algorithms, a course taught by Dr. Stephen Becker (check out his convex optimization research).
You can find the paper/synopsis here. We live-demonstrated this algorithm in class. It was able to pick up Darude Sandstorm under significant noise conditions.
I implemented the 2018 paper "Successive Convexification for 6-DoF Mars Rocket Powered Landing with Free-Final-Time" by Szmuk and Acikmese. This was predominantly as a final project for coursework at Boulder but also to get familiar with successive convexification framework for research. You can find my paper/synopsis here. I also added some cold gas control work at the end to learn how it works. I didn't have time to make it a proper cold gas bang-bang system; but maybe soon.
I also presented similar work at IPPW 2019 at Oxford University, where I implemented the algorithm with slight modifications including MRP dynamics.
ASEN6010 taught by Dr. Hanspeter Schaub has a formative second assignment. It is to derive the equations of motion for N number of variable speed control moment gyroscopes (8 pages of math). This is the most general form of any momentum exchange device derivation: reaction wheels can also be derived with some simplifications on these. Then we were to build a complete attitude dynamics and control framework for infinitely many of these devices in any orientation or momentum configuration.
You can find the assignment here. I learned a lot from this assignment, and think it is worth sharing.
I built an apparatus consisting of a submersible pump, a bucket, and a 3D printed injector plate to continuously run vinegar and water through the regenerative channels for hours to clean it out. I then baked it to flush out the water. Still more work needs to be done; I may be using this for a rocket powered lander project. However, I may likely move to a lower thrust LOX/IPA engine of my own design. I also got a pressure sphere and some Marotta valves... We shall see where this project takes me.
This is a linear quadratic regulator with fixed gain matrix and an extended kalman filter. I wrote this as a final project for MAE6780 Multivariate Control. You can find the paper here. I tried to do some sophisticated guidance. But to be honest, it was just a copy of some CVX work I did previously.
I implemented an algorithm from papers written by Blackmore, Acikmese, Ploen, and Carson. The single problem has a fixed final time, and an outer terminal time optimization loop is run to find the best parameter. I wrote this as a final project for ECE5555 Stochastic Control and Estimation. You can find my paper here
Eric Berg, Adam Weld, and I built this 3DOF Stewart platform for Dr. Bruce Land's microcontroller course at Cornell University. I worked on the hardware and wrote most of the control software. You can find a website detailing this project here (it might take a bit to load).
Please contact me if you would like me to consult on a similar project. This was a super fun project and I have gotten a lot of attention from it.The MkII keyboard is for sale, contact me for more information!
Admittedly, it's a weird hobby. Check my github for some Teensy microcontroller code that can accommodate many different layout matrices. My mkI hardware is a 60% layout with LaTeX bindings. MkII is done and pretty much better in every way. It is completely from scratch, with my own case design that is 3D printed in three parts that slot together. I also like making converters for vintage keyboards like the IBM4074 "Pingmaster"; more on my blog.
This is a finished MkII board. I have made another for a customer. Here you see the MkI hardware with a MkII PCB in the background.
I know. Very cliche. Anyways, this is a 4kW board with 18650s recycled from the hover-board days. I also designed and built the wireless controller from scratch, with the control mechanism a flexible resistor (flexistor?). I will be redesigning this because communication integrity is not quite the best.
Eric Berg and I built a drone and wrote the flight software for my embedded systems course, ECE3140, as a final project. This was just a brute force PID controller; we did not consider dynamics and manually tuned the system.
Eric Berg, Adam Weld, Katie Bradford, and I built a robotic-assisted exo-arm! However, we didn't win anything this year.Devpost.
Eric Berg, Adam Weld, and I won an award at hackMIT! We made a computer vision text-to-speech system that helps the vision impaired by telling them their surroundings, the distance to specific objects, and the describing the ambiance. We on the Amazon prize! This was actually an outstanding project and I would love to recreate it one day. Devpost.
I had the wonderful opportunity of spending a week at Caltech/JPL on mission formulation for a lunar base. The goal was design an architecture that would harvest hydrogen and oxygen from the regolith, and refuel craft in orbit around Earth to increase payload beyond the Earth-Moon system. Many hours spent crunching numbers, few spent sleeping. Also my team won; we all got Microsoft surface pros! You can find the paper here. You can also find a conference paper here. I also got to meet astronaut and SpaceX VP Garret Reisman!
Cornell Artificial Gravity cubesat started as a Master's project. The goal of this spacecraft is to be the first platform to show stable control of artificial gravity with a nonrigid tether. I lead the avionics subsystem for a year where I performed a full-system in-house design. This means that my team and I recognized the requirements for, and designed the PCBs for the power system, flight computer, attitude determination and control, telemetry, and solar power. I also wrote the requirements and outlined the flight software components. The difficulty was in developing three independent avionics subsystems that had to speak to each other and green-light power budgets.
Here you can see the exploded view with tether motors, avionics stack, solar cells, and Kane damper loops for energy dissipation.
This was done in conjunction with 5 other students and the paper can be found here.
Here you can see a CAD view of the avionics stack which takes up approximately 2U, where the rest of the volume is for the high gain parabolic antenna.
I worked on the University Nanosat Program finalist-spacecraft Violet for roughly 2.5 years under the supervision of Dr Mason Peck. I worked across all subsystems from verifying the telemetry/command systems, to building ground stations, to ultimately leading the avionics team. Under this title, I worked on every PCB on the spacecraft, bringing them to full functionality and modifying hardware and firmware as necessary to accommodate de-scoping.
I presented to the Air Force Research Laboratory for three Pre-Integration Reviews (PIRs) and 1 Pre-Ship Review (PSR). Ultimately, they chose to use their funding elsewhere and we ended up working with Ursa Space Systems as a bus for their payload. Again, it seems the plans have changed and Violet resides in Cornell's Sibley school of mechanical and aerospace engineering with Dr. Peck.
Here I am operating on the flight computer:
This was a canned final project for Dr. Schaub's attitude control course, but it was cool and worth posting up here. You can find my report here. The control algorithm is Lyapunov derived nonlinear PD feedback law. Actuator physics is not modeled in this project, please see my other CMG/RWA simulation framework work.
MS in Aerospace Engineering • MS by Fall '19
Working in the Entry systems Design Laboratory under Dr. Braun. I worked on online optimization solutions to the powered descent guidance problem.
BS in Electrical and Computer Engineering• May 2018
With minors in Archaeology and Aerospace. I have vectored my degree towards signals and control systems. I also ran the Cornell Maker Laboratory since 2016. I also did half of my MEng there.
GNC Engineer• Hawthorne, CA • February '20 -- Present
Guidance and control algorithm development for a new satellite project flying in 2020 :)
Associate Engineer• Redmond, WA • Summer '19
I ran environmental test campaigns on V1.0 constellation attitude determination and control hardware, designed Starlink gateway gimbal actuator control boards, and worked on flight simulation framework.
Associate Engineer - Starlink Attitude Control Systems• Redmond, WA • Summer '18
Designed, built, and test flight hardware and software for star trackers on the next generation constellation. Wrote online star tracker debris filtering algorithms. And some other stuff.
Avionics Lead• Ithaca, NY •August '14 - May '18
I led the avionics teams on the Violet Nanosatellite, Cornell Artificial Gravity Cubesat, and Akash Systems satellite. I spent 6 semesters bringing Violet's legacy COTS avionics system to full functionality and held pre-integration and pre-ship reviews with the Air Force Research Laboratory. I led the full-system avionics development of our artificial gravity 3U satellite from block-diagram to traces on boards. All boards were designed in-house. I spent one semester working on the budget-level COTS design of the 6U Akash Systems spacecraft meant to demonstrate communications transponders in the 100Gb/s to 1Tb/s range.
Avionics Hardware Intern• Kent, WA • Summer '17
I built and tested an RF link simulation tool for the New Shepard testbed. I can't talk about it!
Avionics Intern - Dragon RF• Hawthorne, CA • Summer '16
I worked on a TDRSS reradiation system for testing S-band communications on the Dragon vehicles. I developed other RF tools and performed post-mission analysis on Dragon RF subsystems. I held PDR and CDR level meetings with SpaceX and the Jet Propulsion Lab's Deep Space Network Team.
Launch Intern - SLC39A/40• Cape Canaveral, FL • Summer '15
I worked on the instrumentation and range operations hardware required to support the Falcon 9 and Heavy vehicles. During this summer I witnessed the unfortunate CRS7 anomaly from one pad away.
Systems Engineer• Ithaca, NY • August '16 - February '17
I worked on the first design iteration of avionics for a synthetic aperture radar demonstration spacecraft "BearSAR."