Manta

Project Information:

Team Captain: Goro Tamai
Faculty Advisor: Kathleen Allen
Cost: $75,000
Project Time: 1.5 years
Sponsors:

Races:

Sunrayce 95: First place

Media and Displays:

Cambridge 150th Anniversary Parade	September 1996
Massachusetts Special Olympic Games	June 1996
Jr. Solar Sprint	May 1996
Investors' Pasquinade	May 1996
Boston's Earth Day 1996	April 1996
Sneak Preview of "Race the Sun"	September 1997
DOE Sunrayce 97 Kickoff	March 1996
MIT Center for Transportation Studies	September 1995
High Performance Composites	Sept/Oct 1995
Popular Mechanics, "Tech Update"	September 1995
The Discovery Channel: "The Popular Mechanics Show"	Fall 1995
Sports Illustrated - Subscribers' Issue, "On The Scene"	August 1995

Specifications:

Drag Coefficient Cd: ~0.13
Frontal Area Af: ~1 m2
Drag Area CdAf: ~0.13 m2
Weight w/o Driver: 290kg (638 lbs)
Length: 4.55 m (179.0")
Width: 1.98 m (78.0")
Height: 1.01 m (39.8")
Wheelbase: 1.78 m (70.0")
Track Width: 1.27 m (50.0")
Clearance: 0.29 m (11.5")
Wheels and Tires:
Wheels: 16" machined magnesium disc wheels.
Front tires: Michelin Radials, tubeless. 65/80-16. (limited supply)
Rear tire: Moped tire with tubes. 16x2.25".
Rain tires: See rear tire.
Number of Wheels: 3.
Est. Tire Rolling Resistance Coefficient: ~0.006
Number of Flat Tires during the Race: zero
Brakes, Suspension, Steering:
Front brakes: hydraulic calipers, aluminum rotors.
Rear brake: Regenerative.
Front Suspension: Double wishbone with coil-over shock.
Rear Suspension: Aluminum box beam trailing arm with coil-over shock.
Steering: Handlebar to rack-and-pinion to tie-rods, one full Ackermann progression.
Chassis: True-Temper 4130 Chromoly space frame, Gasflux manganese-bronze welded. Tube O.D. range 3/8"~1", wall thickness range: .028"~.035".
Body: Carbon fiber/honeycomb core
Motor: Solectria BRLS8 brushless motor with dual windings, typical power: 800~1600W, peak power 5 kW, redline: 6000 rpm. Solectria MOSFET controller ~89% effeciency including controller at operating point. Lent motor to another team and never re-tuned for peak efficiency.
Control and Instumentation: Accelerator @ right foot, Hydraulic front brakes @ left foot, Parallel/Series motor switch ("gear shifter") @ right hand
Transmission: U.S. Tsubaki extended-bushing 3/8" pitch chain to Azusa sprocket w/ PJ-1 lube. 6.25/1 typical ratio.
Batteries: Trojan deep-cycle lead acid, 306 lbs, 108 volts nominal. Pre-cycled and sorted in lab for maximum capacity.
Solar Cells: ASE Americas, 14% single cell rated efficiency. 724 cells on top, 58 cells on sides (combined), 204 on belly. Peak racing power ~850 watts, Peak charging power ~1280 watts. Four maximum power point boost trackers during racing, one extra during charging.
Panel Voltage: ~95 volts.