A team of CambridgeUniversity students are “set to shine” at this year's World Solar Challenge with an innovative bullet-shaped solar-powered racing car.
Members of Cambridge University Eco Racing (CUER) will take their vehicle on a gruelling 3,000km marathon across the heart of Australia from Darwin to Adelaide.
The engineers have designed and built a vehicle that will use the power of the sun to average 80 km/h in one of the world’s harshest environments. Every element of the ultra-light vehicle has been formulated with the single objective of improving its race time.
Keno Mario-Ghae, CUER team manager and a second year engineering student at GirtonCollege, believes their design has what it takes to beat the competition.
“The margin between first and second place in the 2011 race was just 30 minutes. The narrowly beaten Dutch team are national heroes that previously won the race four times in succession, so we are not underestimating the strength of the competition,” he says.
The student team developed a set of modelling tools and tested and rejected many concepts until they finalised the groundbreaking design named Resolution. The car weighs just 120kg and carries the world’s most efficient terrestrial solar array embedded within a unique aft-facing sun tracking plate that follows the trajectory of the sun. Use of this plate provides a 20% gain in power.
The cockpit is tiny and the four-person driving team must endure four hour stints in 40°C temperatures. Millbrook Proving Ground will provide invaluable experience for driving across all terrains in preparation of the challenge to keep Resolution on the road against fierce cross winds and a substantial road camber.
Practice is essential. In the 2011 competition, the fourth placed team could change a driver and two wheels in less than 30 seconds.
Resolution will have advanced on-board telemetry, which will take into account traffic, weather and driving style, to help advise the team on how to reach their optimum efficiency.
Race strategy is key, and testing at Jaguar Land Rover’s state-of –the-art facility will allow the team to simulate environmental conditions including the Australian sun on a rolling road.
Emil Hewage drove CUER’s entry in the 2011 competition and says that the biggest challenge was a sudden bush fire.
“Our scout car saw the fire and importantly, the shadow cast by its huge smoke plume. We were able to adjust our race plan and pass through the smoke as quickly as possible, to get back into the sunlight. In this competition you are always balancing the budget of energy input against speed gain.”
A rule change in June 2012 was designed to stimulate innovation and make the challenge more relevant to the automotive industry. Only four-wheel vehicles are allowed, with each wheel at the corner of a rectangle, this change has meant many teams were sent back to the drawing board and has opened up the competition for those agile enough to respond.
For example, locating the motor in the wheel hub helps Resolution have a 98% efficient drivetrain, allowing her to exceed speeds of 100 km/h on the power equivalent to a hair dryer.
Resolution’s innovative design reflects the team’s knowledge of automotive engineering and aerodynamics, as well as sophisticated modelling, space-grade composites and optimised solar cells. The result is a vehicle that rewrites the rulebook for solar vehicles but still meets the race parameters and is an exemplar of British ingenuity.
CUER are grateful for the support of Jaguar Land Rover, Cambridge Precision, Millbrook Proving Ground, ARM and the many other individuals and companies that have contributed their support, advice and time.