2007 Prince Alfred College Solar Cycle
Vehicle Specifications

• The concept for an upright bicycle was formed after PAC had built cycles in all other classes in previous years
• Initial motor / gearing and drive train design started back in 2005.
• Initial construction began in 2006 with students inspired by the ‘Bike Technologies’ carbon fibre frames.
• The frame was carved out of polyvinyl foam (DIVINYCELL) and then layered  with about 5 layers of Carbon Fibre and Kevlar using epoxy resin.
• All alloy fittings are high tensile aluminium (steering tube, seat tube etc)
• All wiring and cables are built into the foam
• The covered frame itself weighs about 4-5kg
• The motor is a 24 Volt DC Brushed, 150 watt MAXON motor with a 23:1 gearhead or gearbox. MAXON provide motors to the Mars rover projects and are the highest efficency brushed motors at 91%
• The aluminium cover is a heatsink to maximise efficiency of the motor which is 92%
• The motor is designed to provide assistance to the rider in all gears up to a speed of 60km/h and uses about 5-6 amps of current
• Batteries are Lithium Polymer and each pack on the cycle weighs 3.2 kg.
• Under normal conditions the batteries will provide 3 hours of running time.
• The flexible solar cells cover 0.15sq meters and produce about 25 watts of power. They are used to trickle charge the batteries more than providing instant power.
• The cycle weighs 17kg fully loaded with batteries etc…
• Drag is minimised by using aerofoil shaped frame components and the time trial position
• Construction has been undertaken by students and staff
• Zenith (vehicle name) means the top, best or pinnacle.