October 10, 2002

The biggest test yet of Jose Granda's software will come sometime around April, when a U.S. space shuttle docks with the International Space Station.

That's when Granda will know how well his Computer Aided Modeling Program (CAMP-G) helped engineers create computer models of the flexible structure in space. Granda, a CSUS mechanical engineering professor, was awarded a NASA Faculty Fellowship over the summer to work with engineers and scientists who model the station.

If all goes well - and a battery of tests on Earth and in space say it will - then the station will hardly quiver as the shuttle attaches itself. If everything goes incredibly bad, the station could shake itself into space debris. That isn't likely,
but …

"When you do these simulations, the biggest question is what happens at the time the shuttle attaches to the station, which has a flexible structure," Granda explains. "Obviously, you don't want to produce resonance - the vibrations could destroy the station."

Granda has been improving his software for nearly 20 years. He introduced it to NASA over the summer, when he was at Langley Research Center in Virginia and working with mission control operations at the Johnson Space Center in Houston.
The software translates engineering ideas directly into computer code, allowing engineers to more easily enter information into simulation software such as MATLAB and SiMULINK.

Writing the code manually can require long, tedious hours of work, and is subject to error. And in the space station's case, those hours were multiplied several times over. It's still under construction and changes weight and shape all the time, so NASA has had to complete new mission simulations every time a space shuttle is scheduled to attach to the station to drop off new parts.

"CAMP-G uses Bond Graph Modeling technology and produces the code automatically. It's a way of making the step between reality and the computer a quick step," Granda says.

Granda is internationally recognized for his research. He is the chair of the Bond Graph Modeling Committee of the Society for Computer Simulation and is chair of the upcoming ICBGM'2003 International Conference on Bond Graph Modeling and Simulation.

NASA scientists were impressed enough with Granda's CAMP-G to look into using the software for future missions. He and NASA scientist Raymond Montgomery have begun testing models from Zvezda, the original space station. Their goal is to continue through other space station configurations until they reach mission A12, which is expected to be in April.

NASA was also impressed when Granda made his presentation to a national gathering of NASA scientists. After being just one of seven NASA Summer Fellows chosen to compete with his research presentation, Granda was awarded second place.

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