David Friedman



Hello, I'm David. I work as a software engineer in the aerospace industry. Modeling physical systems, state estimation, and designing robust feedback controllers is what I do.

Projects, Interests

PySextant, a small utility to calculate your position on the earth given two sightings of the sun using, say, a sextant.

Tinymath, a lightweight c library geared toward manipulating vectors of length 3 and 3x3 matrices.

Sensor-cal, a fast c library for performing attitude independant sensor calibrations using a non-linear least-squares optimization.

JuliaOrb, a Julia module for orbital mechanics.

Orbpy, a python module for orbital mechanics. This project is incomplete and will likely stay that way.

This site, how meta.

Strava, the most important project of them all.





Simulation, State Determination, and Control Design for a Small Imaging Spacecraft [pdf]

Control Theory 101 Lunch and Learn [pdf]

Simulation and Control Design for Shape Memory Alloy Torque Tubes [link]

Contacting Me


Keybase, if you'd like my GPG key

Things unrelated to me (but cool just the same)


Good writeup on Loop Transfer Recovery (LTR)

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