Darwin or Bust!

Hey all,

Nathan Golshan wrote a bit about our outback testing, but I'm going to take advantage of my fleeting internet connection to says some more about what we were up to out there.

There are two reasons for test driving in the outback. One reason, of course, is to get the car ready: verify all of the mechanical and electrical systems and tweak the car to fix any flaws that testing reveals. An equally important reason for testing is to get our race team ready to work seamlessly during the race.

Driving a solar car means a lot more than driving one high-tech car across the desert. Our caravan has four other vehicles (scout, lead, chase and truck/trailer) and 21 team members. Every morning the team gets up and charges the car before we drive, by setting up an array stand and pointing the array directly at the sun. Working efficiently with the array stand at the beginning and end of the day means more power, which in turn means we can driver faster. As a result we've been making sure everyone knows their jobs on the race.

After charging and as quickly as possible, the driver gets into the car (a non-trivial task in this car!) and the caravan has to form up. On the actual race scout is the first car. Their job is to look out for large and unusual hazards, remove dead kangaroos from the road, and find good places to pull off the road and camp at the end of the day. Next comes lead, which runs a little bit in front of the solar car and gives warnings about roadkill and cattle grates. Then comes the solar car, sailing grandly away with chase hot on its tail. Chase is the only car that speaks directly to the solar car. It contains our strategy team, which tells the solar car to speed up, slow down, or sail more as necessary. Last but not least is the truck and trailer. The trailer holds our tools during the day and our car at night, as well as doubling as the interior of a shipping container in a pinch. It's a versatile piece of work, engineering by Forest "likes working with wood" Nelson.

The actual race driving is fairly chill: four-hour shifts in Xenith, and if nothing goes wrong the driver's task is to keep the car between the lines for that entire time. One feature of Xenith that makes this a bit more fun for the driver is sailing. The driver has a piece of string taped to the bubble as a wind indicator, and works to keep that string as straight as possible. We tested sailing while we were in the outback--as a driver the primary challenge is to keep the car straight without straight lines to orient on. Normally there is a line in the middle of the array that runs straight forward and can be used to keep in line. When sailing at low angles that line is just a little bit off center; at higher angles it points directly into the other lane or into the path of an oncoming road train, and the driver has to fight with their intuitions to keep going straight.

Road trains are the main things that make driving less chill. They're essentially standard semis with between two and four trailers, and they create strong gusts of wind as they pass. A sign we saw in the Northern Territories said that the road trains could be up to 53.5 meters long!

All this time driving also gave us some time to appreciate the vast scale of the outback. The areas we drove through were not deserts in the sense of the Sahara: no rolling sand dunes, for instance. Instead there were areas with miles upon miles of scrub, stretching off to the horizon in every direction, and vast stretches where the wind whistles across the land and slammed into the car, with no rocks or trees or mountains to stop it. At some point every member of our team has wandered away from camp; for me, such open expanses pull at me to pick a direction and just start walking.

There are also brush fires, which burn vast swatches of the land and throw mushroom clouds of ash up into the air. Driving through burned areas is eerie: the brush burns fast enough that the trees are left intact, but with nothing below them but hundreds of termite mounds that easily reach eight or nine feet in height.

Having made it through the outback for the first time, we are now at the racetrack in Darwin working on the car and doing more test laps. Solar car racing is a lot of "hurry up and wait," with hours of feverish work separated by time waiting for the steering to work or the motor to be assembled so that more tests can be done. Next time I have a chance I'll write about the racetrack and the testing we've been doing here.

Cheers,
Rachel