Purpose

I've been working in the satellite industry since 2001. In each of the jobs that I've held, I've encountered a number of people who are interested in learning about satellites and how they fly but feel intimidated about the topic. I call this the "rocket science factor". I cringe whenever I hear the phrase "Well, it's not like it's rocket science." The aura around that term makes it seem like you need to have a PhD in order to understand orbital mechanics. Well, I feel that is just plain wrong. Like much of physics, the concepts are fairly easy to understand, it's just the symbols, complicated terms, and long math equations that get in the way!

What I'm attempting to do is provide a series of short whiteboard videos which explains the field of orbital mechanics (and also attitude dynamics) without all the crazy math. There may be an equation thrown in every once in a while, but my goal is to minimize how often this occurs. What I want to do is present the concepts...we'll leave the equations for the books. If you find that you still don't understand a topic after watching a video, feel free to contact me at  OrbitNerd at gmail dot com.

 

What is Orbital Mechanics and Attitude Dynamics?

In the purpose statement above, I mention the terms orbital mechanics and attitude dynamics, but I don't describe them. Shame on me...I should know better.

Orbital Mechanics = How a satellite flies through space (i.e. where is the satellite?)

Attitude Dynamics = How a satellite rotates in space (i.e. where is the satellite pointing?)

When people ask me about my job, this is the explanation that I use when I'm in social situations in an attempt to keep people's eyes from glazing over. Let me know if it works.

Who is the Orbit Nerd? 

My name is Luis Baars and I work as a Senior Systems/Software Engineer at Braxton Technologies in Colorado Springs. Before that I worked for Lockheed Martin for 9 years. In my current job, I design and implement orbital analysis and satellite simulation software. I received my masters degree in Mechanical Engineering with a concentration in Space Systems from the University of Colorado at Colorado Springs in 2010. My undergraduate degree was a BA in Mathematics with a Computer Science minor from SUNY Geneseo in 1998.  I have worked on the AEHF, MUOS, SBIRS, GPS OCX, and GMIII satellite programs, mostly in the capacity as the resident orbit and attitude nerd. 

Favorite Books

The following are some of my favorite books in orbital mechanics and attitude dynamics:

Orbital Mechanics: John E. Prussing and Bruce A. Conway  - A good introduction to the basics of orbital mechanics. I've provided a link to the 1st edition, which is the one which I own. There is a 2nd edition available, which I imagine will be similar to the 1st edition with some updates.

Fundamentals of Astrodynamics and Applications: David Vallado  - This is my go-to book for orbital mechanics. It has detailed information about advanced topics in astrodynamics which I find very helpful when designing highly-accurate satellite simulations. This book isn't for the faint of heart but is an invaluable resource if you need the nitty gritty details.

Spacecraft Attitude Determination and Control: Edited by James R. Wertz  - This is an oldie, but a goodie. Excellent coverage of kinematic equations of motion and attitude quaternions. Also has details for a number of perturbing forces used in attitude dynamics.

Analytical Mechanics of Space Systems: Hanspeter Schaub  - Another excellent text. I go to this book the most often since it has development of quaternion equations with the scalar part first instead of last (as it is done in Wertz). At some point I'll have a video up describing this.

Space Mission Analysis and Design: Edited by James R. Wertz and Wiley J. Larson  - Commonly known as SMAD, this book covers multiple areas of space vehicle design. I use this book the most often for its section on link analysis.