09/10/11 – 23:30 (GMT+9:30)
In the eight days since the last blog update, the car has undergone a transformation and driven further and faster than it has since the last race. On Thursday 6th, with the car mechanically and electrically sound (and with clearance to road test from the NT authorities), we took a very shabby Endeavour II out for a spin. No paint, wheel covers, bare carbon fibre patches and no canopy meant we were not the most aerodynamic or prettiest of solar vehicles out on the road, but then we weren’t too worried about the car getting dirty or scratching our paintwork before the prerace events. We saw Nuon’s Nuna6 (odds on favourites to win by all accounts) along with cars from Twente and Umicore (who are running a 3m2 Gallium Arsenide array with concentrators).
The purpose of testing the car before we finished all the work was to hopefully highlight any underlying problems. Mechanically the car passed the day without issue, electrically we found a few niggles. Dan, rather embarrassingly, had cross wired the rear indicators (attempting to signal right resulted in the front right and rear left indicators flashing!) and the brake lights were intermittent – put down to the micro switch on the brake pedal. Between Lucy and George driving, we covered 150km (94miles) and it gave us the opportunity to practice convoy driving and radio communication along the way. Even without our full aero package, George hit 93kph (58mph) without really pushing the car. Whilst we won’t be sustaining that speed in the race, it was comforting to know that all systems seemed to be operating according to plan.
That was until we unloaded at BOC to find the car had no power. The battery discharge contactor was open due to a low cell voltage warning from the battery management system. Slightly disheartened after a good first day of testing, it was found to be the same two cells we had replaced the day before. Eventually Ed diagnosed an internal short on one of the cell management modules was causing the two cells to continually discharge. Whilst excellent to diagnose this has meant replacing the cells again and having to go through the lengthy process of recharging and balancing the pack to operate optimally.
Other than sorting the battery problems, the next few days largely revolved around preparing the car’s shell for painting… but that post (and pictures) will have to wait until the morning.
