SunTiger II

With the knowledge base gained by the design, fabrication, and testing of the team's first prototype solar vehicle, the path to improved performance was clear. The second generation would refine the drawbacks of SunTiger I and carry on its most worthy features.

The first item on the list of improvements was weight reduction. A design goal of 30% weight reduction was set. By using improved methods of shell construction, utilizing magnesium tubing for the frame (causing less wheel scrub), and selecting more efficient batteries with higher energy density, SunTiger II came very close to achieving this goal of dropping more than 230 pounds of the weight of the first solar vehicle.

Decreased aerodynamic and frictional drag was another high priority. By inverting the body shape of SunTiger I, the second prototype was subject to less aerodynamic resistance as well as increased solar array area. Additionally, a new braking system was conceived utilizing bicycle rotors and motorcycle hydraulic calipers.

Another large improvement in SunTiger II technology was the implementation of a wireless telemetry system. This system allowed team members to gather real-time performance data during racing helping us to run at our optimum efficiency.

All of these improvements helped make SunTiger II a better vehicle, but besides improvements in instrumentation and design, experience played a vital role. Having already competed in a Sunrayce, team members were better aware of what racing conditions would be like. The team was better able to work as a whole. Having experience in our back pockets played an important role in making SunTiger II a better competitor.

In June of 1995, the new design proved its abilities. Finishing with an elapsed time thirty hours shorter than SunTiger I and averaging almost twice the speed, SunTiger II proudly crossed the finish line tenth in a field of thirty-eight collegiate competitors.

But the race for faster, more efficient solar transportation is not over. Lessons learned from SunTiger II are pointing the way to further refinements in quality.

SunTiger II Specs

Final standing: 10th place
Weight without driver: 701 lbs.
Motor: Solectria DC brushless
Frame: magnesium tubing space frame
Body: carbon fiber/nomex honeycomb composite
Wheels: three 20" 48 spoke rims with city slick tires at 120 psi