To the moon with a hop

Andrew Abraham has dreamed for years of working in the space program.

Now, as a Ph.D. candidate in mechanical engineering, he is making his dream a reality.

Abraham is one of a team of engineers that is developing a spacecraft that could change lunar flight and research.

His adviser is Terry Hart ’68, professor of practice in mechanical engineering and former NASA astronaut.

Their project is part of a collaboration by Lehigh and Penn State University. The two schools have formed the Lunar Lion Team to compete in the Google Lunar X Prize, which is offering $30 million to privately funded teams that can land a robot on the moon by the end of 2015.

That robot must also be able to travel 500 meters over the moon’s surface and send video and images back to the earth.

To pull off these short hops over the lunar surface, the Penn State-Lehigh team is building a “hopper craft” called the Lunar Lion. Hopping enables a craft to reach the insides of craters and other places that can be difficult to access for a roving machine such as the Mars Rovers, Abraham says.

Optimizing the flight trajectory

Abraham is focusing on guidance, navigation and control (GNC) for the Lunar Lion. One challenge is to optimize the flight trajectory to conserve the chemical propellant the craft will use to hop and land on the lunar surface. This will help with the “traveling salesman” problem.

“We have a finite resource—fuel. Once it’s gone, we can’t fly anymore. We want to visit as many landing sites as possible while minimizing fuel consumption.”

Before joining the Lunar Lion Team, Abraham had never used the software necessary to develop GNC algorithms. That software, Satellite Tool Kit (STK), helps flight engineers calculate orbits. With STK, Abraham can plan the navigation and route of the hopper craft before it launches.

He learned how to use STK himself.

“This software was a constant struggle every day. The biggest difficulty was going from something that works on paper to something that works in real life.

“We had to do it by trial and error.”

Hart has helped Abraham through the project, and Abraham is returning the favor.

“Andrew is doing a great job,” says Hart. “He is helping with the hands-on part of the test bed hopper craft.”

Abraham earned an M.S. in physics from Lehigh in 2009. That summer, he interned at NASA’s Glenn Academy for Space Exploration, where he helped scientists fine-tune a new device that optimizes satellites’ ability to send and receive microwave signals.

Now that he is part of the space program, he has no intentions of leaving.

“In the future, I’d like to work in the space flight industry with unmanned satellites and rovers or manned systems.

“I’ve tried to pursue what I was interested in. You don’t always get the exact thing you want, but sometimes you can get pretty close.”