Virginia Tech engineering student Mark Peretich, left, and his mentor Dave Jennings work on the software project.
Mark Peretich, a Virginia Tech senior who joined the NASA Sounding Rocket Operations Contract's Attitude Control Systems (NSROC/ACS) team as a co-op student in 2007, was a key player in the development of a system called Real Time Attitude Solutions (RTAS) that could prove beneficial in reducing costs of rocket flights.
RTAS is part of Mission 41.075, a sub-tec demonstration launch designed to showcase, test and evaluate new sounding rocket capabilities and technologies. The RTAS technology provides a converging software routine that melds data from a group of onboard sensor suites. RTAS uses an aptly named Gumstix micro-computer running the extended-Kalman filter to calculate three-axis attitude solutions onboard in real time from solar and magnetic fields and a MEMSense three-axis rate integrating gyroscope with integrated digital magnetometer and accelerometers.
Peretich’s software skills allowed the Gumstix microcomputer to provide body-fixed, independent angular measurements with regard to the solar vector and magnetic fields and to combine data collected from those fields with simple coordinate transformations to provide inertial orientation angles within five degrees.
The RTAS team included Peretich, an aerospace engineering student, as the primary software developer. His mentor and senior ACS Engineer Dave Jennings handled hardware, and GNC Tech Pat McPhail managed integration. Together, they turned RTAS into one small but mighty system. The project was completed in an extremely short, three-month timeframe, integrated with the Sub-TEC payload, monitored during extensive tests in NSROC's Testing & Evaluation Lab, and successfully launched on 14 July.
Compared to ACS Systems like the GLN-MAC, which measures internal payload activity with a high rate of accuracy and equally high cost, RTAS offers a new alternative to NASA scientists and investigators seeking low-cost flights. “This was a phenomenal achievement for NSROC, NASA and the business, academic and scientific communities they serve,” said Jan Jackson, outreach manager.
For Peretich it was a rare opportunity for an undergraduate student to work with senior engineers in the field of his choice, accept a formidable challenge, and succeed in actually creating a brand new technology. "We're proud of the 90 students who have worked in our co-op and intern programs," added Jackson. "Many have gone on to get advanced degrees; others are making significant contributions to the aerospace industry. Mark Peretich is among the best of the best!"