MIT's Solar Electric Vehicle Team has won a national 1,150-mile race from Indiana to Colorado, beating out 37 other college teams from North America.
Manta, so named because its profile resembles that of a manta ray, crossed the Sunrayce '95 finish line on June 29 in Golden, CO after withstanding late challenges from both adverse weather and the University of Minnesota team. The race began in Indianapolis on June 20 and consisted of specified legs for each day. The MIT team finished with a total time of 33 hours, 37 minutes, 11 seconds; second-place Minnesota's time was 33:56:00. Rounding out the top five finishers were California Polytechnic University-Pomona (37:03:33), George Washington University (38:55:29), and Stanford University (42:47:12).
Sunrayce is sponsored by the US Department of Energy and General Motors to promote student interest in technology and the environment.
Manta won with an average speed of 37.23 mph, a record for this race. The vehicle's top speed during a downhill stretch was 62 mph, according to team member Matthew Condell, a senior in computer science and engineering. This was the first time that the MIT team had won a national solar-electric race, although it has won New England's Tour de Sol in the past.
Team members attributed their success to a design emphasis on reliability and on Manta's performance during a pre-race qualifying run, which enabled it to start in the number two position. The vehicle did not suffer any breakdowns until the last day of the race, when the motor controller failed (the electronic device that sets the motor's speed based on input from the brake and accelerator pedals). However, team members installed a replacement within 15 minutes. "Most teams had problems here and there," Mr. Condell noted.
Position at the start of the race was also important, given the difficulty of overtaking the many other vehicles (including each team's lead and chase cars) on what was often a single-lane course. "Trying to pass was really hard," said team member Hao Chien, a senior in bioelectrical engineering. By running near the head of the pack, "we could run the competition at our own pace."
Constructed with a chromoly space frame inside an extremely light shell made of carbon fiber with a Nomex honeycomb core, Manta is 14 feet by 6.5 feet and weighs 620 pounds without the driver. It's driven by an 8-hp electric motor run by off-the-shelf lead-acid batteries as required by race rules, which account for half the vehicle's weight.
The MIT team won even though it spent far less money than its competitors (a last-minute truck-use donation by Ryder Service, Inc., arranged by the Center for Transportation Studies, was a big help). Vehicle construction and related expenses for the race came to about $70,000; about two-thirds of that amount came from corporate sponsors with the rest from MIT. In contrast, the University of Michigan spent about $1.4 million but was unable to complete the race, and most other teams spent several hundred thousand dollars, Mr. Condell said.
Others on the 19-member MIT team included Goro Tamai, a graduate student in mechanical engineering, team engineer and principal driver; Milton Wong, a junior in mechanical engineering and team president; and Ivano Gregoratto, a sophomore in chemical engineering and head of the vehicle body composites group. Their advisor is technical instructor Kathleen Allen.
For its next project, the MIT Solar Electric Vehicle Team plans to build a vehicle for either Sunrayce '97 or the World Solar Challenge next year in Australia, considered the world championship event for solar-electric vehicles.
To obtain more information about the Solar Electric Vehicle Team and to see a picture of Manta, access the team's World Wide Web home page at . This page also has a link to the Sunrayce page.
A version of this article appeared in MIT Tech Talk on July 19, 1995.