Since they fly low and home in on a specific area, spy satellites must constantly reboost to maintain a view of their assigned position. That eats up fuel, and when a satellite's power runs out, the crafty contraption is kicked. But what if there was a way to autonomously dock a refueling vehicle on the satellite? Its lifetime could be extended, and national defense could save millions of dollars per year not having to relaunch new spyware.
That's where Ricky Howard and the Advanced Vehicle Sensors Team at NASA's Marshall Spaceflight Center come in: they engineer sensors for autonomously docking spacecraft. As team leader, Howard assists engineers in the development and testing of video sensors that enable spacecraft to automatically rendezvous without the help of a ground crew.
"One aspect of my job that I really enjoy is the variety of test facilities that we have and that I help design and run," Howard says. In the Flight Robotics Lab, a 40- by 80-ft air-bearing floor lets testers "fly" spacecraft using compressed air. Another room holds a large robotic arm that moves the craft while six solar simulator lights shine at a spectrum that matches the sun's. The sensors read the light for positioning information, allowing spacecraft to link up on their own, rather than via remote control.
Recently, Howard was able to move beyond test-facility simulation and into space. He worked on a DARPA-funded Boeing project called Orbital Express, where two satellites spent three months in orbit demonstrating their serviceswapping capabilities.
And from March until July, the serviceable satellite NextSat and its servicing mate ASTRO rendezvoused several times to exchange fuel and upgrades on their own, without help from mission control.
"Some of the (docking) sequences were fairly complex," Howard says. "But we demonstrated that (this process) was almost fully automated."
The job coincides with long-time passions of Howard's: control theory and optics. After completing his undergrad degree in electrical and computer engineering at the University of Alabama in Huntsville, Howard went back for a master's in control theory and a minor in optics.
He says he'd like to be doing more design work, but feels involved vicariously through his team and enjoys helping them through their challenges. Just being involved in projects that will increase the longevity of GPS and spy satellites leaves little time for dreaming. Luckily, Howard has an alternative - going to work every day.
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