Engineering Spotlight: Mandy P., AE

Name: Mandy P.
Major: Aerospace Engineering
Title: Graduate Research Assistant
Company: Georgia Tech

Why did you want to become an engineer, and more specifically, your particular type of engineer?
From a young age I coveted Geordi La Forge’s job on the Enterprise. I wanted to be the one making space travel possible. Sure the captain gets the glory, but it’s the engineer who makes it happen. Since aerospace engineering is the type of engineering that focuses on space travel, I knew this was the appropriate fit for me.

What do you do? (At your job or in your research)
I am a graduate research assistant at Georgia Tech. I work on a design team that’s designing a small 50 kg satellite that will go to space and take thermal images. My job in particular is the lead designer of the “Attitude Determination and Control” Subsystem (ADCS). And no, that doesn’t mean I’m the team’s morale officer.

ADCS is the system that allows a satellite, or even spaceship, to maneuver in space. The system basically uses instruments to look about, determine where the satellite is, and then uses components to adjust the position. In TV and movies, this is usually done with a propulsion system, and propulsion is a type of attitude control. However, in the real world, propulsion is expensive and heavy. Small satellites usually don’t have the mass budget or cost budget for propulsion. So instead, we use things like reaction wheels, CMGs, and torque rods.

So to give you a specific example of ADCS, in our satellite we determine our position using a star tracker. This device looks at the stars. From the stars it’s seeing and the angle its seeing the stars at, it’s able to determine where the satellite must be facing. This information is then sent to our computer which compares this position to where we actually want to be. If the position is not where we want to be, it sends a command to our reaction wheels. Reaction wheels are basically spinning wheels within the satellite, which spin faster or slower based on commands. This change in their speed changes the orientation of the satellite (weird, huh? – it all has to do with conservation of angular momentum – more on that in a later post). The satellite then changes position, and the star tracker starts the process again by checking the stars. Basically, the position of the satellite can be changed continuously.

What do you do outside of engineering?
I like to read SF/F, write SF/F novels, and write this blog. I’m also quite the TV addict. Basically, I’m your standard nerd, but that’s not true of all engineers, as you will see in some of their engineering spotlights.

Anything else you would like us to know about you or your work?
My work is really cool. Satellites rock. ADCS is hard. Yeah, that’s all I’ve got.