The Great Ocean Road

The group is back in Melbourne now. We just packed the shipping container this morning, so apart from cleaning and returning the VW vehicles, team responsibilities have basically ended. Now everyone is planning their next steps, be it to Sydney, New Zealand, or elsewhere.

Since we had no time constraints this time around, the team took the Great Ocean Road back to Melbourne. The road winds along the coast in a similar fashion to California's highway one, with dramatic cliffs plunging into the ocean, expansive views of the South Pacific, and the occasional beach hamlet where one can stop to get some good fish and chips.

I just wanted to share some of the pictures I captured along the route. Hope you enjoy them.

Race Wrap-Up

Well, the 2011 World Solar Challenge is over.

It was one of the most interesting races in recent memory. While the event usually enjoys nearly perfect sunshine, this year the outback decided to give us high winds, huge brushfires, persistent high altitude clouds, large intermittent cloud banks, and in the driest state of the driest country on the planet, rain. In short, conditions were not ideal for racing solar cars.

As you may have gathered from the provisional race results, we did not finish the entire course. Only 7 out of 37 teams teams traveled the entire distance under solar power, a much lesser proportion than the sunny 2009 race, which saw 10 out of 25 teams finish under their own power.

The last day of the race for us was hard on everyone. We knew we were in bad shape the evening before, when we failed to get any significant amount of array stand charging in due to cloud cover. Despite a forcast for clearer skies, the morning failed to produce much more power – only about 200W from the array. Close to midday, we managed to get the car on the road and start chugging along out of Glendambo at less than 30kph on the dismal amount of power the cloud cover was allowing us to produce. We had a small glimmer of hope that if we could maintain this speed, it might be enough to finish the race in time for the hard deadline in about 28 hours. We fought, very slowly, through many long, gradual hills and some light rain, but at some point we pulled over after we had been reduced to traveling at about 15kph and the battery pack had tripped for low voltage for the umpteenth time. We crunched some numbers, and even assuming that day 7 was all sun, we would not have been able to finish the race. This was the point where the team gathered, and after some quiet introspection, made the crushingly difficult decision to put the car in the trailer and continue to Adelaide. We packed up, got in the cars, and drove quietly over the last 400 kilometers of the race route.

On Saturday morning, we ceremonially rolled across the finish line, and with no less cheer than everyone else, celebrated the end of the race by soaking ourselves in the fountain – several of us even got thrown in by other teams as they rolled across the finish line.

According to the race officials’ calculation, our final placement was 12th overall. We finished 4th in the Production Class, which is generally equal to any team not using Michelin tires. This result, while not terrible, is not what we were hoping and dreaming would come of this car. It’s been especially hard for the many team members who have put immense amounts of time and effort into building this car from the ground up with their own minds and hands. Now it’s time for the team to step back, analyze what went right and what went wrong, confront the problems that arose from new perspectives with new solutions. This car may not have performed to our best informed expectations, but this team is not defeated. To quote the unofficial motto of the Stanford Solar Car Project – ever onwards.

An extended lexicon of solar car

--Scumbag (noun and verb): a scumbag is, in the words of Ian Girard, "Someone who's using the blowtorch to fry ants when you need to use it to crimp things." You can scumbag a laptop, a tool, or a car. Our team's scout car was a diesel Golf and was nicknamed "Scumbag Scout" for the duration of the trip, thanks to people's tendency to take it and go drive randomly across Australia without warning.

--Hack (verb): an unplanned solution to an unexpected problem, usually involving the gross misuse of power tools. Our hack team is quite strong--through the use of an air-powered dremel and a butane soldering iron they succeeded in resurrecting our half-dead motor on the side of the road.

--Dece (adjective and exclamation): Good. Great. Awesome. Sometimes even decent. With the application of more Red Bull, "dece" usually becomes "most dece." Most frequently heard from Greg and Sam when pacing around the shop.

--Karplus (verb): to destroy through the overeager application of excessive force. Paul Karplus, our motor man, is capable of applying infinitely more force to tools than most mere mortals. The shop is littered with the remains of bolts and end mills that tried to defy him.

Day Six Update

Hello everyone. As you might have gathered, things aren't going as well as we would have hoped.

This is the morning of day 6. Our strategy, contingent on good weather, had us rolling into Adelaide this morning. Unfortunately, the weather is absolutely terrible. For the next day and a half, nearly all of South Australia is under a huge front of clouds - which means we're producing very little power from our array. Our array is more efficient at producing power than anyone else in the race, but at this point it makes little difference.

The top three teams, Tokai, Nuon, and Michigan, have finished the race in that order, coming in under the last rays of sunshine. No one else was successful in outrunning the cloud front that has settled over the area. This leaves many teams, including us, with the dismal outlook of having nearly empty battery packs, while our solar arrays produce only minimal power. Whether any more teams will actually manage to finish the race is still a matter of debate.

We may be able to pull enough power out of our excellent array closer to midday today to get the car on the road and start chugging along at 30kph or less. This might be enough to finish the race in time for the hard deadline about 28 hours from now, but it's going to be close.

We'll keep you posted as best we can on our progress. Wish us luck with the weather.


On a brigter note, here's some sweet pictures I've taken over the past two days. Even in the face of terrible luck and disappointing in the performance of our car, Australia is a beautiful country.

Race Update and Recap

Good morning from the third day of the race. Here's an update on how things are going and a recap of the first two days.

Day One: We got off to a fast start of the line. We started seventh out of about 40 teams, and climbed to 5th by passing Twente and Sunswift, who broke down and took a wrong turn respectively. Unfortunately, about 200 km out of Darwin, we had a relatively routine tire change. In the rush of putting the motor back in the car after we seated the new tire, we accidentally damaged a mechanical component that held the axle of the motor from spinning. This means the motor's stator spun freely when we accelerated, damaging the wiring of the motor. Luckily, we were able to fix the issue, but we lost two hours on the side of the road in the process. We got back on the road after this and made it to Dunmarra for the night.

Day Two: Things went significantly more smoothly yesterday. We ran into a few obstacles over the course of the day, including a large cloud of smoke from a controlled brushfire, as well as some high-altitude clouds which messed with our insolation. Our motor had some hall-effect sensor issues at low speeds remaining from the first day, but they didn't prevent the car from moving at high speed, as the motor no longer uses these sensors. We still experienced a higher than expected power draw from the car, and much of the team was in a resigned mood and at a loss for where our power was dissapearing to. On the bright side, our array is working brilliantly, and we estimate we're producing about 10% more array power than any of the leading teams. We stopped for the night in Tennant Creek, where Paul and Sasha stayed up all night and completely repaired the motor.

Now, the current situation. The race has been stopped about 116km south of our current position, due to a huge brushfire that completely decimated the town of Barrow Creek and the surrounding area. Teams were stopped at Tennant Creek as they arrived yesterday. The fire cleared enough to restart the race this morning, and the teams are setting off according to the timing in which they arrived. This puts us at a departure time of 11:57 am. This is a blessing and a curse for us, strategy wise - if we had known that this would be the situation at Tennant Creek, we would have driven faster yesterday to improve our position in the race, since we would have time to charge this morning. In our current situation, our state of charge is better, our time is worse, but we get even more time to charge on the array stand as we approach solar noon. It's very complicated to find the balance that gives us a net benefit, but it works out to be close enough to even either way.

We'll be taking off from here soon with a full battery pack, so we can hopefully improve our position somewhat going forward. We'll keep you updated as we pass internet access points. 

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

Into The Outback

Xenith sails successfully.

Yesterday, the solar car team started testing in the outback. We were set back by a rough transition to the new BPS, but today around noon the electrical system became fully armed and operational, and we started getting significant test miles on the car under race conditions.

 

The big milestones of the day were testing our sailing configuration and tuft testing. Sometime in the afternoon we attached many tufts of yarn over the surfaces of the car, to see if airflow was separating at any point on our aerobody. It wasn't a comprehensive test, but that wasn't the point - we ascertained that the flow over the array is very, very laminar, and the flow over the fairings is also very clean. The most interesting part of the test was the bubble, however. We were driving with a significant crosswind the whole day, which caused a large vortex over the back of the bubble foil when the car was pointed in the direction of travel,which of course causes a lot of pressure drag. However, when we changed the sail angle of the car to the full 7 degrees into the wind, we observed the tufts become firmly attached to the bubble surface again, indicating that the boundary layer had once again attached to the car. The final verdict is not yet in on the exact quantitative benefit of sailing, but this is a pretty significant success.

The goal tomorrow is to drive north in a full mock race day, with array stand charging in the morning, driving from 8 to 5 with a short mock control stop, and charging again in the evening. The numbers we got for power consumption over our excellent telemetry system today look very competitive, but another full day of testing tomorrow along with some other tweaks to the car will help us determine if it's the best. Here's hoping we can pull it off.

Preparing In Adelaide

For the last three days, the team has been in Adelaide, South Australia. Adelaide is the only large city in SA, and the position of the finish line for the race. It served as our staging area for our planned mock race north to Darwin, 2000 miles away.

Our VW sponsorship payed off yet again, as a VW dealership just outside the city center gave us a roomy garage bay for us to work on the car in. From 9 to 9 the first two days, we worked on the car nonstop, swapping the electrical system for the new revision, getting code up and running, building the new motor, making a few small mechanical changes, and getting the trailer and caravan ready for the race. Yesterday, we worked until noon, and then loaded everything up and drove to Port Augusta, about 200 miles north of Adelaide and the last town deserving of the name until Alice Springs, the center of the outback.

Adelaide is an interesting city, in a strange kind of way. It's a very clearly planned city, with overly wide streets, bike lanes, nice sidewalks, and a comprehensive tram system. It's laid out in a strict but spacious grid, with large public squares and pedestrian only zones in many places, The city is surrounded by a large park, completely encircling the central district in a moat-like fashion. It's nice in one context, but it lends the entire place a kind of static, lifeless feeling, even when the city is out partying on a Saturday night. It's also very expensive, even for Australia - a fast-food chicken sandwich can cost you about 10 dollars.

Next, it's off to see the outback, and get some miles on the car.

A brief lexicon of solar car

Some of the words we use on this blog might not be entirely familiar to you. Some of you might even be scratching your heads and wondering, "Don't these kids speak English?" To alleviate some of your confusion, here are a few key solar car words:

--Beast (verb): To complete a project, come hell or high water. When beast mode is engaged, your work will be done, and it doesn't matter how many bones you've broken in the last week, how many cans of energy drinks you have to leave crumpled in your wake, or how few hours you have to sleep to get it done.

Example usage: "Paul beasted the motor in 40 hours of nonstop machining." "Xenith has arrived. Engage beast mode!"

--Derp (verb): The opposite of beast. Someone who is derping is not doing useful work, and is often avoiding work. For instance, I'm derping by writing this blog post.

Derp can also be an expression of boredom. If someone is standing around with nothing to do, they might simply say "derp." It's a negation--a lack of meaning.

Derp is so flexible that it means something different in the past tense. Someone who has derped has messed something up, generally in a stupid way or by not thinking about what they are doing.

That's all for now--I encourage you to never use these words in normal conversation, for they are strangely addictive. I'll post more words as I see fit, or if I see an egregiously incomprehensible post on this website.

Cheers!

Zanzibar