Quick links and news from the past few days. In no particular order:
Scientific Gems has posted a summary of the WSC route.
News story about SunSpec's return from their August fire. The SunSpec team is also rapidly posting new photos of the car to their Facebook page. Note the half-cells on the module on the nose of the car, presumably to boost the voltage of the small modules and better fill the space. The car looks really good, doubly so for a car that was built in little more than a month! I'm deeply impressed, and wish them the best of luck in the race. They've already sent some members on their way to Adelaide.
News story about TAFE SA.
Sunswift's eVe is now fully road legal.
The first group of Tokai team member have departed for Melbourne.
Twente has been approved to test drive on Australian roads. They also revealed that they are doing 4-wheel steering, which has helped make the two fairings on the left even smaller.
The Megalux team members have arrived in Darwin today.
CUER is testing Evolution at the Alice Springs Inland Dragway today, as part of their trip north from Darwin to Adelaide.
Anadolu has posted a Road to WSC video onto their Facebook page.
Ardingly's car has cleared customs and the team is doing emergency response training.
WSU has departed for Darwin
Wednesday, September 30, 2015
Tuesday, September 29, 2015
SunSpec Racing is Back In Action
SunSpec posted a new team photo and new video to their Facebook page today. The caption for the video confirms that this is new footage of the car driving on September 29th, and that the old car was indeed destroyed by the fire in their workspace on August 25th.
That's an amazingly quick turnaround time, and I applaud the team for their efforts! Building a new solar car in a single month is a near-unbelievable accomplishment.
They've named the new car Phoenix, which I suppose is appropriate, if a bit unimaginative. (Oregon State did the same thing when their car self-immolated)
That's an amazingly quick turnaround time, and I applaud the team for their efforts! Building a new solar car in a single month is a near-unbelievable accomplishment.
They've named the new car Phoenix, which I suppose is appropriate, if a bit unimaginative. (Oregon State did the same thing when their car self-immolated)
Monday, September 28, 2015
WSC 2015 Updates: Monday Sept 28
Things are getting busier down in Australia; let's check in and see how things are doing!
Challenger Class
2: University of Michigan
We heard some rumors early in the week, and they turned out to be correct: Aurum's battery is detained in Hawaii for some unspecified reason. We're reminded of MIT's similar issue from four years ago, but it shouldn't be as much of a disaster for Michigan - they have oodles more time than MIT did. It sounds like the team is already back in business! They've started their mock race, which entails driving the race route backwards - from Adelaide to Darwin.
4: Antakari Solar Team
There has been no news from the team since we started doing weekly updates on Sept 21st. Their little blurb on the Bridgestone WSC page shows a photo of the old car, and only a rendering of Intikallpa IV.
This is a team that I am definitely worried about.
This is a team that I am definitely worried about.
7: MIT Solar Electric Vehicle Team
MIT's car arrived in Sydney over a week ago. No major news from the team since then, but the team wants to go fast.
8: Punch Powertrain Solar Team
Punch is hanging out in Darwin, grilling with Bochum. They posted some nice photos to Flickr earlier this week.
9: Adelaide University Solar Racing Team
As far as I can tell, the team hasn't made any updates this week
10: Tokai University Solar Car Team
No updates about Tokai this week.
12: Cambridge University Eco Racing
CUER has put together a fantastic social media page, complete with a cute little annotated map. They're also making daily blog updates. The team has spent most of this week traveling north across the outback towards Darwin. In related news, Nigel Stephens published a guest post over on Scientific Gems with some interesting perspectives on the car.
The first members of UKNZ's team have arrived in Adelaide. They will drive the race route in reverse up to Darwin, where they will meet up with their solar car. The team also has a brand new YouTube channel.
15: Team Solaris
16: Stanford Solar Car Project
Stanford posted two new updates to their blog this week (1, 2), as well as a bunch of photos to Facebook. It looks like the team is testing the car pretty heavily. They also posted a nice little video of them Arctan in California earlier this summer.
17: NWU Solar Car
No updates on the status of the team or the car, but they've been actively posting promotional infographics to Facebook. I particularly like the one comparing the weight of their car to a family of kangaroos.
18: EcoPhoton Solar Team
The team posted a new picture of the car to Facebook a few days ago. They shipped the car about three weeks ago, so maybe the car is in Australia? Or is it an old picture? The team has their work cut out for them once the car arrives, as I don't think it had the array installed by the time it shipped.
21: Solar Team Twente
Twente has been outfitting their strategy vehicle (always good for the strategy people to have wood to knock on) and preparing the car. They've posted a bunch of photos to Flickr and their blog. They also made a post about the design of Red One (they say that as far as they know, they are the only asymmetric catamaran with three fairings instead of two, but they must not have looked at the field very closely - NWU, Durham, and Beijing all share that design feature as well). We briefly discussed their post in the comments.
22: Siam Technology College
No news on the car since it shipped out on September 12th. The week, the team received personal blessings from the Supreme Patriarch of Thailand.
23: MegaLux GAMF
The car landed in Singapore last week, and is being shipped by ocean for the last leg. The team will soon depart for Australia themselves.
25: Goko High School Solar Car Team
Since this team does not have any social media or website, no updates :(
26: Durham University Solar Car
The ship with Durham's car was near Taiwan at the start of the week. The first team members have departed for Darwin.
27: RVCE Solar Car Team
The team is still posting thank-you messages to sponsors on Facebook... but otherwise has not made any updates on the car. Their section on the Bridgestone WSC page only has a photo of the team, not the car. The website is still dark.
This is a team that I am definitely worried about.
This is a team that I am definitely worried about.
30: Team Arrow
32: Principia Solar Car
Principia posted on Tuesday that most of the team will be departing on October 9th, but two members will be leaving within the week to meet Ra9 in Australia. That certainly won't leave the team with much time to get acclimated and re-acquainted with the car; inspection starts on the 13th...
36: Anadolu Solar Team
The Anadolu team noted in these comments on Facebook that the team should be arriving in Australia this week.
46: JU Solar Team
47: Nagoya Institute of Technology Solar Car Team
If I understand this post correctly, the team has been training a new driver with a solar car borrowed from another Japanese team. They can't use their own car, because it shipped quite a while ago.
51: KIT Solar Car Project
77: Blue Sky Solar Racing
80: Beijing Institute of Technology
82: Kookmin University Solar Car Team
No updates since the car shipped two weeks ago.
Cruiser Class
We made a big post on the 2015 Cruiser cars this week, check it out!
11: Hochschule Bochum SolarCar Projekt
It's been a busy week for Bochum. They've showed off their world class kitchen team (seriously, they always have had the best food. Way too good for a solar car team), got SunRiser professionally aligned, reassembled their battery, and just started test driving in Australia. They've also made a blog post about their first week in Australia.
The team has built this awesome strategy workstation in one of their support vans. Note, like Twente, that wood is close to hand for knocking on.
Random thought: I wonder if they intentionally cut the parting line for the rear hatch so that it looks like a Porsche 914 when the hatch is removed? I can't unsee it.
The team has built this awesome strategy workstation in one of their support vans. Note, like Twente, that wood is close to hand for knocking on.
Random thought: I wonder if they intentionally cut the parting line for the rear hatch so that it looks like a Porsche 914 when the hatch is removed? I can't unsee it.
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SunSpec posted a very short video of the car driving to Instagram this week. I'm not sure if this is a *new* video, or if it's form the same set of videos and pictures they posted to Facebook in August.
31: ITS Solar Car Racing Team
I can't find any updates from this week.
33: IVE Solar Car
35: University of Minnesota Solar Vehicle Project
The team finally took possession of their car Eos this week, five days after they initially said they were going to pick it up. No idea what happened there, but at least they have the car.
38: Persian Gazelle Solar Car
After years of social media silence, this team is posting new pictures of the car every day - I think they're really proud of their work! The car shipped in the middle of last week, and the team posted some photos to Instagram that appear to show the car doing high speed testing on a race track.
40: Solar Team Eindhoven
Eindhoven posted a big english language update to their website. They're also testing to see who will get to drive the car during qualification.
43: Ardingly Solar Car
This high school team packed up and shipped their Lotus 7 based car in the middle of last week. I completely did not expect these folks to finish the car, given what it looked like when I started this blog three week ago. Congratulation to the team! Check out this post about the team and their car, and the team's launch video. Nigel Stephen also made a guest post on Scientific Gems about this team and their car.
45: KGHM Lodz Solar Team
No major updates since shipping the car a little over a week ago.
75: UNSW Sunswift
88: Kogakuin University Solar Vehicle Project
It's been a busy week for Kogakuin. They have a group that has arrived in Adelaide after some issues with their flights - it sounds like they initially had some trouble with their rental cars too, although I think that's been sorted out. In these comments the team says there is a second group heading directly to Darwin to pick up the car. Kogakuin's car Owl is also heavily featured in the second half of this WSC introduction video from Bridgestone.
The team also made a post about their double bubble roof (was this in response to little ol' me?). They seem to be confident that it's a net advantage, but I'm a little curious what level of detail they went to in their solar simulation. I'm sure it's a clear win if you just look at it from a solar insolation standpoint, but did they simulate the losses in the boost converters for all of those small modules?
Adventure Class
6: PI Solar Car
Withdrawn. This was their first race outside of their home country; the team says they underestimated the amount of planning required for finances and logistics, and they missed critical shipping deadlines. We wish them the best of luck in the future.
20: Houston Solar Race Team
34: Liberty Christian Solar Car Team
No updates this week; the car is due in about a week and a half.
42: TAFE SA Solar Spirit
No updates this week.
Saturday, September 26, 2015
Cruiser Class Part 2: WSC 2015
Today, we're going to look at the 2015 Cruiser field in depth, and discuss which are our favorite cars and why.
In our Cruiser Part 1 post earlier in the week, we noted that the very low solar/grid energy ratio was disappointing to some teams, and the dearth of information around how practicality would be judged made it extremely difficult to engineer a winning car - there was simply too much guesswork involved. WSC has partially addressed both of these issues in 2015.
For starters, WSC has changed the scoring equation for the Cruisers. The cars will be scored the same way in the same four categories, although the balance is different - Energy is now 15% (down from 18.87%), elapsed time is 70% (up from 56.60%), person-km is 5% (down from 5.66%), and practicality is 10% (down from 18.87%). That last change is particularly welcome.
In addition to making the practicality portion a much smaller part of the overall score, they've also somewhat addressed the lack of information about the practicality judging itself. The regulations give examples of what the judges may be looking for, so at least the judging isn't a complete black hole this year. The officials only make one definitive statement in the regs: "A Cruiser Class Solar EV that has been granted an unconditional Road Registration (street legal) in the team's home country will be highly regarded" (bold for emphasis).
The practicality regs also note "Entrants will be invited to brief the judges on their design philosophy, which may include the desire to focus their design effort on a particular market segment" and that one of the things that judges may find desirable is "suitability for declared purpose". So spinning a good story for the judges will play a factor. The wise-ass in me would be really tempted to state "our design philosophy was to design a car to be the fastest at the world solar challenge" and then brush off all other practicality concerns as "not in line with our design philosophy", but that might not get very far with the judges...
If you're interested in reading the precise language of the Cruiser scoring rules, check regulation 4.3 in the 2015 regs. Practicality scoring is 4.3.2.4.
They've also reduced the number of grid-charging locations from three down to one - the Cruiser teams will only be able to suck juice off the wall at Alice Springs. This means that, for most cars, the majority of their energy will come out of their solar arrays, rather than off the grid. On the other hand, since the energy usage portion of the overall score is down slightly (and elapsed time is MUCH more important), I don't think there's a winning strategy anymore than involves doing the race on pure solar power (not that any teams tried that in 2013). I almost guarantee EVERY single car is going to take that wall charge in Alice Springs.
These changes make me happier than I was in 2013, but they haven't fixed a more fundamental issue: array sizing. The Cruiser cars wouldn't need the huge batteries or the grid charging option if they were simply able to collect more solar power. Two seat solar cars have been competitive in the past - the '96 Honda Dream was a back-to-back two seater, and it won WSC outright! More recently, the two-seat ISF6000 cars (2001(?) to 2005) competed directly with the single seat ISF5000 class cars. They were allowed to be 6m long and 2m wide; 33% larger than the 5m long and 1.8m wide single seat cars, and had correspondingly larger solar arrays. Given this extra array, the two seaters were competitive with the single seat cars, even with the same sized (or very similar sized) battery packs.
Nowadays the single seat cars have shrunk to 4.5m long, and for some reason WSC is holding the Cruiser class to the same size and array limits as the single seat cars - despite the fact that they're far heavier and less aerodynamic. I really wish the Cruiser class would be given more array area (and more space to put the array on) instead of just piling the batteries in and letting them charge off the grid; it would sure make for a better solar car event. Maybe WSC doesn't think that's compatible with their stated philosophy for the Cruiser Class "...to encourage solar cars designed for practicality and acceptance in a given market segment", but I don't see a conflict.
Anyway, onto the cars. Twelve teams have entered the Cruiser Class this year, which isn't a huge step up from the eleven that entered in 2013 (Only eight actually made it to the event). We've already talked about all of the teams a little bit in our introductory post, but here are our favorites (in order), and why:
I had to convince myself to go out on a bit of a limb and put Kogakuin's Owl as my #1 choice. As much as I like how the car looks, cars don't win races - teams win races. Kogakuin doesn't have a history of performance at WSC, so this is a bit of a risky call on my part. On the other hand, Nuon was a new team when they won in 2001, and Tokai hadn't been to WSC in 13 years when they took home the gold in 2009...
And when we look at Owl, everything about it looks highly professional. It appears that they are being very strongly supported and sponsored - see how their car is extremely heavily featured in this video that Bridgestone put out. The fit and finish on the car appears exemplary, even on that curvy array.
Their car design looks like a near ideal best blend of aerodynamics and array performance for a two-seat car, given the constraints of the rules (upright seating and facing forward - no back-to-back laydown seating like in the '96 Honda Dream). It's also hot as hell - DAT TUNNEL. Sure, there appear to be zero concessions for practicality, but elapsed time is so much more important in the scoring rules this year and practicality is much less important, so I think this was actually a great design decision. The car looks like it's been engineered to win. Given the big battery and the extra grid charge in Alice Springs, I think this car might even be matching speeds with some of the top Challenger class cars.
The "double-bubble" Zagato roof looks sweet, but I think it's a little silly - I suspect it negatively impacts the array more than it helps the aerodynamics.
Every solar car instinct I have screams "this is the car to beat" and the rough numbers I've been running appear to back up that gut feeling - I honestly expect them to run away with the event. It'll be a much tighter race between some of the cars below, though.
Bochum's an experienced team and they always run a good race. The SunRiser looks extremely well built; if I didn't know any better, I'd say it almost looks production ready! Maybe my opinion will change when I see the cars in person, but I think out of all the 2015 Cruiser cars, this is the car that I'd want in my driveway.
This should be a higher performance car than their entry two years ago. Sure, it's a little heavier than SunCruiser (360kg vs 340kg, if you believe the datasheets that solar car teams put out), but it looks way more aerodynamic. It's longer, lower, sleeker, and only seats two (rather than three). While the rear end still cuts off vertically to provide a flat spot to mount the license plate, it's *only* sized to fit the license plate, unlike the big flat back that was on SunCruiser. I appreciate the attempt to increase the performance of the car at WSC while simultaneously increasing the practicality - this article claims the car has a backup warning system, power locks, and heated seats! (However, I'm not sure how pitman arm steering demonstrates "everyday practicality")
They're going to be hurt by that GaAs array, though - it's nice to not have to deal with finding places for 6sqm of solar cells *and* big windows for multiple occupants on a car with 8.1sqm of planview area, but their car will generate significantly less solar power than some of the other cars.
It's not going to be the fastest car down the course, but I expect Bochum to do quite well.
UNSW is bringing back their 2013 Cruiser car, eVe. They had a lot of trouble with the car last time, and still managed to be the fastest Cruiser car on the course (although that only netted them a 3rd place finish).
Hopefully they've used the last two years to iron out all the bugs. Sometimes I'm a little leery of teams bringing back cars from previous events - you'd think with all of the extra time to train and polish up the car's systems they'd do quite well, but time and again I've seen teams returning with old cars do extremely poorly - there's just some sort of spark missing when there's not all of the constant pressure to get the car done.
I don't think that has happened to UNSW, though. The team has been running around and keeping pretty busy with eVe, which I think is a good sign. Last summer, they took the array off and used the car to set some sort of complicated fastest-electric-car-over-a-500km-distance-without-recharging world record. In order to achieve that, they strapped on a fancy extended tail to fix some of the bad aero on the blunt back of the car, which sadly I believe is too long for them to use at WSC. They've also made some pretty serious upgrades to the headlights and doors.
Unfortunately, since they're bringing an old car, they're stuck with some of the fundamental design decisions made last time - emphasizing styling over aerodynamics and array performance. I still laugh every time I see those 3-cell modules on the fenders. Hopefully they at least get some sweet style points from the practicality judges.
I'll be upfront - realistically I don't think this team will do that well, but I was extremely tempted to slot them in a place or two higher. That aero design! While I'm not confident in some of the aerodynamic details, I love the concept - a no-concessions-to-practicality design, with the rear passenger appearing to actually straddle the driver bobsled style. If it were a known-good team fielding this car - like, say, Stanford or Twente - it would be at the top of my list list.
But this is from a team that was founded in 2005 or so, and has only competed (relatively unsuccessfully) in 2 major races - the 2006 World Solar Rally in Taiwan, and the 2011 World Solar Challenge. They initially designed Persian Gazelle III for WSC 2013, but pulled out about a month before the event with no explanation. Although the pictures of the car seem to match the renderings from the spring of 2013 reasonably closely, no actual photos of this car existed until two weeks ago, so I suspect it was only completed quite recently.
The team hasn't raced in four years, and as a university team, they've probably had quite a lot of turnover since then. I suspect this will be a major learning experience for the team, rather than a tour de force. If I have to be realistic, they'll probably finish the course but be at the very back of the pack.
Who knows, maybe they will surprise me!
In our Cruiser Part 1 post earlier in the week, we noted that the very low solar/grid energy ratio was disappointing to some teams, and the dearth of information around how practicality would be judged made it extremely difficult to engineer a winning car - there was simply too much guesswork involved. WSC has partially addressed both of these issues in 2015.
For starters, WSC has changed the scoring equation for the Cruisers. The cars will be scored the same way in the same four categories, although the balance is different - Energy is now 15% (down from 18.87%), elapsed time is 70% (up from 56.60%), person-km is 5% (down from 5.66%), and practicality is 10% (down from 18.87%). That last change is particularly welcome.
In addition to making the practicality portion a much smaller part of the overall score, they've also somewhat addressed the lack of information about the practicality judging itself. The regulations give examples of what the judges may be looking for, so at least the judging isn't a complete black hole this year. The officials only make one definitive statement in the regs: "A Cruiser Class Solar EV that has been granted an unconditional Road Registration (street legal) in the team's home country will be highly regarded" (bold for emphasis).
The practicality regs also note "Entrants will be invited to brief the judges on their design philosophy, which may include the desire to focus their design effort on a particular market segment" and that one of the things that judges may find desirable is "suitability for declared purpose". So spinning a good story for the judges will play a factor. The wise-ass in me would be really tempted to state "our design philosophy was to design a car to be the fastest at the world solar challenge" and then brush off all other practicality concerns as "not in line with our design philosophy", but that might not get very far with the judges...
If you're interested in reading the precise language of the Cruiser scoring rules, check regulation 4.3 in the 2015 regs. Practicality scoring is 4.3.2.4.
They've also reduced the number of grid-charging locations from three down to one - the Cruiser teams will only be able to suck juice off the wall at Alice Springs. This means that, for most cars, the majority of their energy will come out of their solar arrays, rather than off the grid. On the other hand, since the energy usage portion of the overall score is down slightly (and elapsed time is MUCH more important), I don't think there's a winning strategy anymore than involves doing the race on pure solar power (not that any teams tried that in 2013). I almost guarantee EVERY single car is going to take that wall charge in Alice Springs.
These changes make me happier than I was in 2013, but they haven't fixed a more fundamental issue: array sizing. The Cruiser cars wouldn't need the huge batteries or the grid charging option if they were simply able to collect more solar power. Two seat solar cars have been competitive in the past - the '96 Honda Dream was a back-to-back two seater, and it won WSC outright! More recently, the two-seat ISF6000 cars (2001(?) to 2005) competed directly with the single seat ISF5000 class cars. They were allowed to be 6m long and 2m wide; 33% larger than the 5m long and 1.8m wide single seat cars, and had correspondingly larger solar arrays. Given this extra array, the two seaters were competitive with the single seat cars, even with the same sized (or very similar sized) battery packs.
Nowadays the single seat cars have shrunk to 4.5m long, and for some reason WSC is holding the Cruiser class to the same size and array limits as the single seat cars - despite the fact that they're far heavier and less aerodynamic. I really wish the Cruiser class would be given more array area (and more space to put the array on) instead of just piling the batteries in and letting them charge off the grid; it would sure make for a better solar car event. Maybe WSC doesn't think that's compatible with their stated philosophy for the Cruiser Class "...to encourage solar cars designed for practicality and acceptance in a given market segment", but I don't see a conflict.
Anyway, onto the cars. Twelve teams have entered the Cruiser Class this year, which isn't a huge step up from the eleven that entered in 2013 (Only eight actually made it to the event). We've already talked about all of the teams a little bit in our introductory post, but here are our favorites (in order), and why:
Kogakuin
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| (image source) |
And when we look at Owl, everything about it looks highly professional. It appears that they are being very strongly supported and sponsored - see how their car is extremely heavily featured in this video that Bridgestone put out. The fit and finish on the car appears exemplary, even on that curvy array.
 |
| (image source) |
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| DAT TUNNEL (image source) |
Every solar car instinct I have screams "this is the car to beat" and the rough numbers I've been running appear to back up that gut feeling - I honestly expect them to run away with the event. It'll be a much tighter race between some of the cars below, though.
Bochum
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| SunRiser (image source) |
This should be a higher performance car than their entry two years ago. Sure, it's a little heavier than SunCruiser (360kg vs 340kg, if you believe the datasheets that solar car teams put out), but it looks way more aerodynamic. It's longer, lower, sleeker, and only seats two (rather than three). While the rear end still cuts off vertically to provide a flat spot to mount the license plate, it's *only* sized to fit the license plate, unlike the big flat back that was on SunCruiser. I appreciate the attempt to increase the performance of the car at WSC while simultaneously increasing the practicality - this article claims the car has a backup warning system, power locks, and heated seats! (However, I'm not sure how pitman arm steering demonstrates "everyday practicality")
They're going to be hurt by that GaAs array, though - it's nice to not have to deal with finding places for 6sqm of solar cells *and* big windows for multiple occupants on a car with 8.1sqm of planview area, but their car will generate significantly less solar power than some of the other cars.
It's not going to be the fastest car down the course, but I expect Bochum to do quite well.
UNSW
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| Sweet Koenigsegg doors and new headlights on eVe for 2015 (image source) |
Hopefully they've used the last two years to iron out all the bugs. Sometimes I'm a little leery of teams bringing back cars from previous events - you'd think with all of the extra time to train and polish up the car's systems they'd do quite well, but time and again I've seen teams returning with old cars do extremely poorly - there's just some sort of spark missing when there's not all of the constant pressure to get the car done.
I don't think that has happened to UNSW, though. The team has been running around and keeping pretty busy with eVe, which I think is a good sign. Last summer, they took the array off and used the car to set some sort of complicated fastest-electric-car-over-a-500km-distance-without-recharging world record. In order to achieve that, they strapped on a fancy extended tail to fix some of the bad aero on the blunt back of the car, which sadly I believe is too long for them to use at WSC. They've also made some pretty serious upgrades to the headlights and doors.
Unfortunately, since they're bringing an old car, they're stuck with some of the fundamental design decisions made last time - emphasizing styling over aerodynamics and array performance. I still laugh every time I see those 3-cell modules on the fenders. Hopefully they at least get some sweet style points from the practicality judges.
Eindhoven
In 2013, the scoring equation was such that a 4-seat solar bus could conceivably win head-to-head against an efficient 2-seat car. Eindhoven chose the slightly-riskier-but-more-media-friendly design, and it paid off when all of the 2-seat cars encountered major problems on the race. Sometimes, car design ends up having nothing to do with it... and it all comes down to team preparation, training, and pre-race practice and debugging.
This year, Stella Lux has some visible aerodynamic improvements over 2013's Stella. The windshield is visibly more raked and pointed, and the car is slightly narrower - although the array is still full width, protruding to either side. And then there's the tunnel where the battery was in the previous car. However, with the scoring equation changes and only one charging location this year, I do not believe the Stella Lux will have enough performance to be a major contender for the overall win. It's simply too heavy and not slippery enough.
(slight aside: My coworker views Stella Lux's tunnel with deep suspicion. "With that sort of length-to-width aspect ratio, at those Reynolds Numbers, it's an entropy generator")
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| Stella Lux (image source) |
(slight aside: My coworker views Stella Lux's tunnel with deep suspicion. "With that sort of length-to-width aspect ratio, at those Reynolds Numbers, it's an entropy generator")
Minnesota
Prior to WSC 2013, I thought Minnesota had the best chance of winning the Cruiser Class. Daedalus looked like it was a very careful blend of high performance with minimal practical features (but not ignoring them outright). They were definitely the team that most boldly poked the black box of the practicality judging. Unfortunately, they were crippled by malfunctioning custom motors, and the team was in frantically-repairing-while-limping mode for the entirety of the race, so we never got to see the car really stretch its legs.
Given the team's design philosophy at the last WSC, and how the scoring rules changed this year to emphasize speed and simultaneously de-emphasize practicality, I assumed we'd see a more refined version of Daedalus - or maybe an even more radical design. But their new car Eos looks like a major shift towards the practicality end of the spectrum, which is a very puzzling decision to me given the scoring changes.
Assuming they plan to take this car to the American Solar Challenge, a minor wrinkle in their design is the ASC side-impact regs - which require at least 15cm of clearance between the edge of the car and the driver. This could explain the awkward shape on the side of the car, but overall the whole car just looks... not great. Eos looks visibly rough around the edges in the photos, and I really doubt it will do all that much better than Daedalus's crippled performance two years ago.
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| (image source) |
Assuming they plan to take this car to the American Solar Challenge, a minor wrinkle in their design is the ASC side-impact regs - which require at least 15cm of clearance between the edge of the car and the driver. This could explain the awkward shape on the side of the car, but overall the whole car just looks... not great. Eos looks visibly rough around the edges in the photos, and I really doubt it will do all that much better than Daedalus's crippled performance two years ago.
Persian Gazelle
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| Persian Gazelle III render from March 2013 (image source) |
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| Persian Gazelle III in mid September of 2015 (image source) |
The team hasn't raced in four years, and as a university team, they've probably had quite a lot of turnover since then. I suspect this will be a major learning experience for the team, rather than a tour de force. If I have to be realistic, they'll probably finish the course but be at the very back of the pack.
Who knows, maybe they will surprise me!
Lodz
This is a new team with a new car. The car doesn't look particularly aerodynamic, but looks respectably well built, and I hope that it'll at least finish the race. It's a surprisingly small car - note they've had to put a fairly large panel of cells on the dash.
The Rest
I don't have too much to say about the rest (SunSpec, ITS, IVE, Istanbul, Ardingly). They're all teams that are either brand new or haven't performed well in the past - I don't believe any of them have actually ever completed WSC. None of the cars really stand out to me as particularly noteworthy, it's been a long week, and I've typed way too much here already.
SunSpec was probably the best looking car of the bunch but not sure how they'll do after the fire - they posted this image to Facebook almost a week ago, but haven't been heard from since. EDIT Sept 9th: SunSpec is back in action.
Ardingly's little Lotus 7 based car is cute, and they should be very proud if they even start WSC - that's a major accomplishment for a high school team.
SunSpec was probably the best looking car of the bunch but not sure how they'll do after the fire - they posted this image to Facebook almost a week ago, but haven't been heard from since. EDIT Sept 9th: SunSpec is back in action.
Ardingly's little Lotus 7 based car is cute, and they should be very proud if they even start WSC - that's a major accomplishment for a high school team.
Strategy and Predictions: Speeds, People, Energy.
Speed: I expect Eindhoven will probably average a little above 60kph, while Bochum and UNSW will likely average slightly less than 70kph - Bochum likely with a slight edge over UNSW. Ultra aerodynamic cars like Kogakuin *should* theoretically be able to edge above 80kph average speed; legitimately running with the top Challenger teams (remember, even though they're heavier and have more aero drag, the Cruisers have about 50% more total energy available!).
People: I'm going to reverse my previous position here - I think it's probably better to carry the 2nd person around. This is one of those cases where other teams' activities affecting your own score comes into play - if another team carries two people, it's definitely worth it to match them so that you don't lose points, even though it weighs you down some. Even with the revised scoring equation this year, I think the points lost by going fractionally slower are offset the points that aren't lost due to fewer people.
Energy: Like I said far, far above: given how important elapsed time is in the score this year, I can't imagine that anyone will skip the opportunity to top of the pack off the grid in Alice Springs - unless they're specifically trying to make a point of doing the race only on solar.
Practicality: Kind of a crapshoot again, but at least we have some data to go on from last year. Eindhoven and Bochum scored in the upper 80% ranges, several teams scored just above 70%, Minnesota's high performance/low practicality car managed to score a 69.3%, and only KUAS scored lower, with a 50.3%. However, given how small of a part practicality is in the score this year, it may not matter at all. If Bochum scored a 90% in practicality, Kogakuin could edge faster by only 5kph or so, and would only need 50% or higher in practicality to win.
Practicality: Kind of a crapshoot again, but at least we have some data to go on from last year. Eindhoven and Bochum scored in the upper 80% ranges, several teams scored just above 70%, Minnesota's high performance/low practicality car managed to score a 69.3%, and only KUAS scored lower, with a 50.3%. However, given how small of a part practicality is in the score this year, it may not matter at all. If Bochum scored a 90% in practicality, Kogakuin could edge faster by only 5kph or so, and would only need 50% or higher in practicality to win.
Wrapup
Ok, I've typed a hell of a lot of words here. TL;DR, Kogakuin is by far my favorite to win, Bochum and UNSW will probably duke it out for 2nd. Beyond that is murkier, but Eindhoven is probably a good bet for 4th.
Best of luck to all of the teams!
Best of luck to all of the teams!
Friday, September 25, 2015
Bridgestone Sponsorship at WSC
Nigel Stephens pointed out this page to me, which details Bridgestone's sponsorship of the entries into WSC this year. There's a nice little writeup on each of the teams they're sponsoring, and links to all of their social media - I've updated all of the links on my team pages (somehow I'd missed every single one of the youtube accounts for the Japanese teams).
Of note, it looks like Bridgestone is giving a whole bunch of teams their new Ecopia solar car tire. As far as I know, Kogakuin was the only team using the new Ecopia at WSC in 2013, but it looks like up to 19 teams are going to be using them this year. Notably missing from the list of sponsored teams are all of the Dutch teams and all of the American teams - which shuts all of Tokai's major competitors out from getting the new tires.
The 14" Bridgestone Ecopia EP80 was a staple of the solar car racing world for years, but it's a slick tire and therefor hasn't been allowed at WSC since 2007 - for 2009 onward, WSC has required a minimum tread depth. Dunlop also never updated their SolarMax tire to comply with those regs, so teams have basically been stuck with Michelin Radial X at the past three WSC events if they want to be competitive - and they're very hard to acquire. Schwalbe's WSC-compliant version of the Energizer S was introduced in 2011(?), but it just doesn't seem to have been able to meet the performance of the Radial X.
The solar car world really needs another source of competitive tires, and I wonder if that Ecopia can perform. It'll be interesting to see if they give Tokai (and MegaLux) an edge over Michigan, Nuon, Stanford, and Twente in the Challenger class - and Kogakuin, UNSW, and Lodz an edge over the rest of the Cruiser class.
If anyone can find a datasheet with a Crr value for the new Ecopia, I would be very interested to see it!
Other notable things off the Bridgestone page:
Of note, it looks like Bridgestone is giving a whole bunch of teams their new Ecopia solar car tire. As far as I know, Kogakuin was the only team using the new Ecopia at WSC in 2013, but it looks like up to 19 teams are going to be using them this year. Notably missing from the list of sponsored teams are all of the Dutch teams and all of the American teams - which shuts all of Tokai's major competitors out from getting the new tires.
The 14" Bridgestone Ecopia EP80 was a staple of the solar car racing world for years, but it's a slick tire and therefor hasn't been allowed at WSC since 2007 - for 2009 onward, WSC has required a minimum tread depth. Dunlop also never updated their SolarMax tire to comply with those regs, so teams have basically been stuck with Michelin Radial X at the past three WSC events if they want to be competitive - and they're very hard to acquire. Schwalbe's WSC-compliant version of the Energizer S was introduced in 2011(?), but it just doesn't seem to have been able to meet the performance of the Radial X.
The solar car world really needs another source of competitive tires, and I wonder if that Ecopia can perform. It'll be interesting to see if they give Tokai (and MegaLux) an edge over Michigan, Nuon, Stanford, and Twente in the Challenger class - and Kogakuin, UNSW, and Lodz an edge over the rest of the Cruiser class.
If anyone can find a datasheet with a Crr value for the new Ecopia, I would be very interested to see it!
Other notable things off the Bridgestone page:
- In the Asia-Pacific tab, at the bottom - the first photos I've seen of Beijing's car!
- Still no photo of RVCE's car
- Only a rendering of Intikallpa IV, next to a picture of Intikallpa III.
Tuesday, September 22, 2015
Cruiser Class Part 1: Background, and 2013 Reflections
Today, we're going to take a deep dive into the Cruiser Class, starting with a look back at 2013.
In addition to the Challenger class, the little single-seat race cars we all know and love, WSC announced a second class for 2013 - the Cruiser class. For the public perspective, the big news was that these cars would have more than a single seat (reg 2.25 specified "two or more seats", but interestingly, did not specify a maximum number of occupants). For the teams, however, the big news was that the way the winner would be determined was radically different.
With very few exceptions, solar car events are *races* - the fastest car to complete a fixed distance wins (a small number of events - mostly on closed course tracks - are over a fixed length of time, and the car that goes the furthest wins). The Cruiser class, however, would be scored on several aspects of performance, of which speed was only one portion. The four categories were:
Many other design competitions use a computed score to determine a winner (The competitions in the SAE Collegiate Design Series spring to mind, as does the Solar Decathlon), but the rules and regulations always very clearly spell out precisely how the competitions will be judged and scored. In comparison, literally only giving a single sentence description of a factor worth 18.87% of a team's score - "Practicality will be judged by an Expert Panel" - was a sick joke.
Prior to the race, I did some rough performance calculations anyway, and decided to just ignore practicality altogether. After running through some sims, it became pretty clear that the highest performance designs would be aerodynamic two-seaters of some sort. The winning race strategy would be to drive with two people in the car at all times - the balance between scoring for person-km and elapsed time made the extra weight worth it - and to only use the middle charging location in Alice Springs. A maximum efficiency, no passengers, no-grid-charging run was plausible as a winning strategy, but allowed little to no margin for error, and using all three charging locations would cost more points than would be gained by shorter elapsed time. 3-seaters and more would simply be too un-aerodynamic to keep up without charging at all three charging locations, and the penalty for increased energy usage would more than negate the extra points in person-km. I figured (guessed) that the delta in practicality between +3-seaters and 2-seaters would not be big enough to make up for the performance difference.
Ultimately, eleven teams entered the Cruiser Class in 2013, and eight competed.
First, let's look at one of the teams that didn't make it to WSC:
The University of Tehran first competed at the World Solar Rally in Taiwan in 2006, and brought Persian Gazelle II to WSC in 2011, finishing 31st out of 37 with about a third of the course completed. The team was constructing Persian Gazelle III to compete in the Cruiser class at WSC 2013.
The car appeared to be a highly-aerodynamic two seat car, with the occupants seated in-line. The driver bubble was so short that I assumed the rear passenger would be straddling the driver, bobsled style. This is almost exactly how I would design an upright-seating two seat solar car if practicality were not a concern. It's also how I would expect a team to design a car if they wanted to also be competitive at events that did not have a two-seat class.
In any event, the renderings that they posted to Facebook in March were the last we saw of them. They withdrew from the event without public explanation about a month before the event.
The team has since finished the car, and entered it into the WSC 2015 Cruiser class. I'm very excited to see the car in Australia.
Here are the teams that actually showed up in 2013:
Solar Team Eindhoven was a brand new team hailing from the Netherlands, the same country as Nuon and Twente. They were clearly shooting for maximizing practicality - they brought a 4-seat car named Stella, with a reasonably complete looking interior. The long upward-opening doors were a little janky, though - definitely awkward to get in and out of, especially the front seats.
The large flat top meant they were the only(?) Cruiser team to be able to fit a full 6sqm of cells onto the top surface of the car. They charged by rolling the car up onto ramps and popping up the rear hatch to normalize further.
The University of Calgary entered their two-seat Schulich Delta into the Cruiser Class. Notably, they placed some solar cells on the sides of the car, rather than carrying an auxiliary array inside the car.
In addition to the Challenger class, the little single-seat race cars we all know and love, WSC announced a second class for 2013 - the Cruiser class. For the public perspective, the big news was that these cars would have more than a single seat (reg 2.25 specified "two or more seats", but interestingly, did not specify a maximum number of occupants). For the teams, however, the big news was that the way the winner would be determined was radically different.
With very few exceptions, solar car events are *races* - the fastest car to complete a fixed distance wins (a small number of events - mostly on closed course tracks - are over a fixed length of time, and the car that goes the furthest wins). The Cruiser class, however, would be scored on several aspects of performance, of which speed was only one portion. The four categories were:
- Energy usage. In addition to 3x as large batteries as the Challenger class (up to 66kg of LiPo), Cruiser teams were able to charge off the grid at three locations - Tennant Creek, Alice Springs, and Coober Pedy. Each time the teams connected their cars to the grid, it would be assumed they had taken a full battery's worth of charge - WSC did not actually measure how much energy was taken off the grid.
- Elapsed time. (Hopefully self explanatory)
- Person-kilometers. The number of people in the solar car for each leg multiplied by the distance of each leg. Person-km only count for seats that are continuously occupied between control points.
- Practicality. The only information given was "will be judged by an Expert Panel" and this category was otherwise a complete black box.
- 18.87% for energy usage
- 56.60% for elapsed time
- 5.66% for person-km
- 18.87% for practicality
To determine a team's score in each category, their performance would be normalized relative to the highest performing team in that category - so a team's score partly relied on the actions of *other* teams, certainly an interesting wrinkle. Folks who are interested in reading the precise wording of the scoring rules should look at reg 6.95 from the 2013 WSC regulations.
When teams were discussing which class they wanted to design for, a few common objections to the Cruisers came up again and again. For starters, the size of the battery - and particularly the grid charging portion - didn't sit very well with some teams. If a team used the largest battery allowed and charged at all three grid charge locations, well over half of their energy (perhaps even over 2/3rds) would have come off the grid. That doesn't make for much of a solar car race.
The other common (and larger) complaint was the "practicality" portion of the score. It was such a large percent of the score, and teams were given absolutely no information about what WSC was looking for or how it would be judged. Given that most design features to enhance "practicality" would compromise the performance of the car, in order to win, it would be crucial to get the proper balance of performance and practicality. But there simply was not enough information given to make even the most basic design decisions. Unless you had a skilled telepath on your team, every design tradeoff would be a wild stab in the dark. Several teams were not willing to risk a 18 months their of time, effort, and money based on blind guesses about what the judges would want to see.
The other common (and larger) complaint was the "practicality" portion of the score. It was such a large percent of the score, and teams were given absolutely no information about what WSC was looking for or how it would be judged. Given that most design features to enhance "practicality" would compromise the performance of the car, in order to win, it would be crucial to get the proper balance of performance and practicality. But there simply was not enough information given to make even the most basic design decisions. Unless you had a skilled telepath on your team, every design tradeoff would be a wild stab in the dark. Several teams were not willing to risk a 18 months their of time, effort, and money based on blind guesses about what the judges would want to see.
Many other design competitions use a computed score to determine a winner (The competitions in the SAE Collegiate Design Series spring to mind, as does the Solar Decathlon), but the rules and regulations always very clearly spell out precisely how the competitions will be judged and scored. In comparison, literally only giving a single sentence description of a factor worth 18.87% of a team's score - "Practicality will be judged by an Expert Panel" - was a sick joke.
Prior to the race, I did some rough performance calculations anyway, and decided to just ignore practicality altogether. After running through some sims, it became pretty clear that the highest performance designs would be aerodynamic two-seaters of some sort. The winning race strategy would be to drive with two people in the car at all times - the balance between scoring for person-km and elapsed time made the extra weight worth it - and to only use the middle charging location in Alice Springs. A maximum efficiency, no passengers, no-grid-charging run was plausible as a winning strategy, but allowed little to no margin for error, and using all three charging locations would cost more points than would be gained by shorter elapsed time. 3-seaters and more would simply be too un-aerodynamic to keep up without charging at all three charging locations, and the penalty for increased energy usage would more than negate the extra points in person-km. I figured (guessed) that the delta in practicality between +3-seaters and 2-seaters would not be big enough to make up for the performance difference.
Ultimately, eleven teams entered the Cruiser Class in 2013, and eight competed.
First, let's look at one of the teams that didn't make it to WSC:
University of Tehran
 |
| PGIII render from March 2013 (image source) |
The car appeared to be a highly-aerodynamic two seat car, with the occupants seated in-line. The driver bubble was so short that I assumed the rear passenger would be straddling the driver, bobsled style. This is almost exactly how I would design an upright-seating two seat solar car if practicality were not a concern. It's also how I would expect a team to design a car if they wanted to also be competitive at events that did not have a two-seat class.
In any event, the renderings that they posted to Facebook in March were the last we saw of them. They withdrew from the event without public explanation about a month before the event.
The team has since finished the car, and entered it into the WSC 2015 Cruiser class. I'm very excited to see the car in Australia.
Here are the teams that actually showed up in 2013:
Bochum
 |
| PowerCore SunCruiser (image source) |
Bochum had been building practical-appearing solar cars for several years, culminating in the two-seat SolarWorld GT at WSC in 2011, despite the fact that no two-seat class existed at the time. In 2013, they brought PowerCore SunCruiser, a 3-seat car. The driver was front and center, with passengers behind and to either side.
Like many of the past Bochum cars, it had a 3sqm gallium-arsenide (GaAs) solar array. Given that silicon solar cell efficiency is creeping up to 25%, and GaAs cells top out around 30%, most teams go with the 6sqm silicon arrays. But on a multi-seat car, a smaller GaAs array allows much more flexibility with big windshields, doors, and curvier surfaces. Many Cruiser teams that went with silicon arrays were not able to get the full 6sqm on the exterior of the car, and had to pack some of the array onto auxiliary panels - packed inside the car while driving, and only utilized while statically charging.
It was quite a small car - only about 4.2m long and 1.6m wide.
Solar Team Eindhoven
 |
| Stella (image source) |
The large flat top meant they were the only(?) Cruiser team to be able to fit a full 6sqm of cells onto the top surface of the car. They charged by rolling the car up onto ramps and popping up the rear hatch to normalize further.
UNSW
 |
| eVe (image source) |
UNSW's teasers prior to the event claimed they were building a "solar supercar", and the car certainly looked the part - if I had to pick a single one of these to show off in my driveway, this would be it. Their sporty side-by-side two-seater, eVe, utilized a tunnel underneath the car to reduce the aerodynamic drag. This is the sort of shape of car I was expecting most teams would bring - one that looks kind of like a normal car, with fancy aero on the underbody. However, UNSW compromised the performance of the car too much in the name of style for me to take it very seriously. Those fender flairs with the little 3-cell modules on the top of each were hilarious. The panel closest to the camera in this photo is all cells that were carried inside the car while driving; they probably could have put half of those cells on the top of the car if they'd made the fenders flush with the array, rather than protruding.
University of Minnesota
 |
| Daedalus (image source) |
The University of Minnesota came back to WSC for the first time since 1999 with a very aerodynamic appearing two-seat Cruiser car called Daedalus. The two occupants were very cozy, and the seats were accessed by sliding the whole hatch forward. They were unable to fit the full array on the exterior of the car, and utilized two small auxiliary arrays in the morning and evening.
This car looked like it struck a very good balance between maximizing performance while slightly hedging bets against the practicality judging.
University of Calgary
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| Schulich Delta (image source) |
TAFE SA Solar Spirit
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| Solar Spirit (image source) |
The team from Technical and Further Education South Australia brought their car Solar Spirit. It was a two seat car, with the driver compartment accessed through a forward tilting hatch. The team had previously raced this car at WSC 2011, only completing 801km of the course.
Goko Industrial High School
 |
| Kaiton II (image source) |
The team from Goko entered their car Kaiton II. Looking back at photos, I honestly can't recall wether it was a two seat or four seat car. Ton Boon has kindly pointed out that it was a two seat car.
Kaohsiung University of Applied Sciences
 |
| Apollo VII (image source) |
The team from Taiwan brought Apollo VII, one of the strangest looking cars in the event. A lot of us were sure the rendering that was posted to their team profile page had to be a joke, but the car looked exactly like the render. When they crossed the line at the end of the race, the big wide wing was gone and I'm not sure what happened to it.
Summary
Out of the eight cars that competed, there was a single four-seat car, a single three-seat car, and six two-seat cars. Only two of the cars appeared to emphasize aerodynamics in any major way - most were very high frontal area "solar bus" or "normal passenger car" style vehicles. It's clear that most teams that did enter the event had decided to emphasize practicality over performance, rather than design to win the scoring equation.
Results
Only four teams in the 2013 Cruiser class managed to finish the race: Eindhoven, Bochum, UNSW, and Minnesota. Final results for those four teams were as follows:
It's hard to draw too many conclusions about the various car designs due to the small sample size, and extenuating circumstances that affected each team. Minnesota was crippled by malfunctioning motors and barely managed to finish the race at all (sacrificing many power FETs in their motor controllers in the process). UNSW's car was finished at the last moment and had host of minor electrical bugs and other issues. Notably, the passenger door would not latch, so they had to tape the door shut. It is expressly against the rules to tape an occupant exit hatch shut, so they were not allowed to put a person in the passenger seat. They had to drive with only a single person in the car for the entire race.
Interestingly, the practicality scoring was fairly tight. Eindhoven scored the highest with 88.3%, and Minnesota scored the lowest of the finishers with 69.3% (KUAS was the only team to score lower, with 50.3%). But remember, scores are normalized relative to the highest scoring team in that category! So Eindhoven effectively got 100% for the category, and Minnesota scored 78.5% relative to Eindhoven. This is not a huge spread, considering the visibly apparent differences in the practicality of their two cars! Reports that I read said that the "expert panel" consisted of several journalists for car magazines, among others. Jeroen reported that the appeared to be judging the cars on cargo space, the number of seats, and parallel parking, among other things.
Knowing what we now know about how the practicality scoring went down, let's speculate a bit. Playing with the numbers, it looks like if the more aerodynamic cars - Daedalus and eVe - had worked properly, one of them probably could have won it. If either car had worked right, they *should* have been able to only use one of the three charging locations - which would have put a huge damper on the score of Stella and SunCruiser. To win using one charging location and two people in the car at all times, they would have had to average about 70kph - a little slower than Bochum, but a little faster than Team Arrow, the 7th place Challenger team. Given that they would have had 6x the amount of energy charged off the grid than Arrow did, that certainly should have been achievable for slippery two-seaters.
Ultimately, the 2013 Cruiser Class came down to team and car preparation more than it came down to the design of the cars. We'll see what lessons the teams, new and old, learned when they compete this year.
For 2015, the Cruiser Class is largely the same, although WSC has slightly addressed the two major pain point that we discussed earlier in this post. They have reduced the external grid charging locations to only one, in Alice Springs; this means at least half of a team's energy will have to come from the solar array. The cars will be scored in the same four categories, although the balance is different - Energy is now 15% (down from 18.87%), elapsed time is 70% (up from 56.60%), person-km is 5% (down from 5.66%), and practicality is 10% (down from 18.87%). They've also come to their senses and clarified practicality at least a little in the rules - although they don't commit to anything, they mention that the judges may be looking for "...ease of access and egress, ease of operation, reliability, versatility, style, suitability for declared purpose...". They outright state that being registered as a street legal vehicle in the team's home country will be "highly regarded".
We'll discuss the 2015 Cruiser field in depth in another post.
- Eindhoven: 1st place, 97.5% overall
- Elapsed Time: 40 hours, 14 minutes
- Person-km: 9093 km, avg 3.01 people in the car
- External Energy Usage: 64.0 kWh
- Practicality: 88.3%
- Bochum: 2nd place, 93.95% overall
- Elapsed Time: 41 hours, 38 minutes
- Person-km: 6484 km, avg 2.15 people in the car
- External Energy Usage: 63.5 kWh
- Practicality: 87.0%
- UNSW: 3rd place. 92.18% overall
- Elapsed Time: 38 hours, 35 minutes
- Person-km: 3022 km, avg 1 person in the car
- External Energy Usage: 64.0 kWh
- Practicality: 70.7%
- Minnesota: 4th place, 79.18% overall
- Elapsed Time: 51 hours, 41 minutes
- Person-km: 5454 km, avg 1.8 people in the car
- External Energy Usage: 64.0 kWh
- Practicality: 69.3%
It's hard to draw too many conclusions about the various car designs due to the small sample size, and extenuating circumstances that affected each team. Minnesota was crippled by malfunctioning motors and barely managed to finish the race at all (sacrificing many power FETs in their motor controllers in the process). UNSW's car was finished at the last moment and had host of minor electrical bugs and other issues. Notably, the passenger door would not latch, so they had to tape the door shut. It is expressly against the rules to tape an occupant exit hatch shut, so they were not allowed to put a person in the passenger seat. They had to drive with only a single person in the car for the entire race.
Interestingly, the practicality scoring was fairly tight. Eindhoven scored the highest with 88.3%, and Minnesota scored the lowest of the finishers with 69.3% (KUAS was the only team to score lower, with 50.3%). But remember, scores are normalized relative to the highest scoring team in that category! So Eindhoven effectively got 100% for the category, and Minnesota scored 78.5% relative to Eindhoven. This is not a huge spread, considering the visibly apparent differences in the practicality of their two cars! Reports that I read said that the "expert panel" consisted of several journalists for car magazines, among others. Jeroen reported that the appeared to be judging the cars on cargo space, the number of seats, and parallel parking, among other things.
Knowing what we now know about how the practicality scoring went down, let's speculate a bit. Playing with the numbers, it looks like if the more aerodynamic cars - Daedalus and eVe - had worked properly, one of them probably could have won it. If either car had worked right, they *should* have been able to only use one of the three charging locations - which would have put a huge damper on the score of Stella and SunCruiser. To win using one charging location and two people in the car at all times, they would have had to average about 70kph - a little slower than Bochum, but a little faster than Team Arrow, the 7th place Challenger team. Given that they would have had 6x the amount of energy charged off the grid than Arrow did, that certainly should have been achievable for slippery two-seaters.
Ultimately, the 2013 Cruiser Class came down to team and car preparation more than it came down to the design of the cars. We'll see what lessons the teams, new and old, learned when they compete this year.
For 2015, the Cruiser Class is largely the same, although WSC has slightly addressed the two major pain point that we discussed earlier in this post. They have reduced the external grid charging locations to only one, in Alice Springs; this means at least half of a team's energy will have to come from the solar array. The cars will be scored in the same four categories, although the balance is different - Energy is now 15% (down from 18.87%), elapsed time is 70% (up from 56.60%), person-km is 5% (down from 5.66%), and practicality is 10% (down from 18.87%). They've also come to their senses and clarified practicality at least a little in the rules - although they don't commit to anything, they mention that the judges may be looking for "...ease of access and egress, ease of operation, reliability, versatility, style, suitability for declared purpose...". They outright state that being registered as a street legal vehicle in the team's home country will be "highly regarded".
We'll discuss the 2015 Cruiser field in depth in another post.
PI Solar Car Team Withdraws from WSC 2015
PI Solar Car Team announced today via Facebook that they were withdrawing from the World Solar Challenge this year. They performed extremely well at the inaugural Abu Dhabi Solar Challenge earlier this year, finishing 2nd place to the University of Michigan in a nail-bitingly-close race. The team is citing a lack of experience with the logistics involved in an overseas race as their reason for withdrawing - they missed some key shipping deadlines.
We are sorry to hear this, and wish them the best of luck in the future.
The start of the race is about a month away, and this is typically around the time when teams that won't make it to the race begin to officially withdraw.
We are sorry to hear this, and wish them the best of luck in the future.
The start of the race is about a month away, and this is typically around the time when teams that won't make it to the race begin to officially withdraw.
Monday, September 21, 2015
WSC 2015 Updates: Monday Sept 21
The University of Michigan posted a brief overview of the WSC contenders. Scientific Gems made a whole bunch of good posts this week, go and check them out. Zero-to-Darwin, a Japanese website for solar car and eco-car competition coverage, has posted a pre-race report on WSC 2015.
As always, we welcome tips if we've missed anything.
Still no social media or new about this team. Nigel Stephens pointed out that WSC has updated their team profile page with a rendering of an asymmetric catamaran. A render was all that was available of their car prior to WSC 2013 as well, and the car that showed up to that event appeared exactly as rendered.
The team has posted more photos of their new car to their website and instagram. Particularly interesting is this photo showing off the seating position. Definitely tight in the back for the passenger...
As always, we welcome tips if we've missed anything.
Challenger Class
2: University of Michigan
Michigan is down in Adelaide preparing for the race. They recently showed off their car at a WSC press event, along with Stanford and the University of Adelaide.
Nuon has had a busy week. They've done some sightseeing and had a beach BBQ with Punch, Twente, and Eindhoven. They had some minor hiccups getting Nuna8 out of Australian customs/quarantine but were ultimately able to take possession of the car.
4: Antakari Solar Team
No updates from this team on the car - still unsure if the car has shipped or not. Best wishes to all of them, their friends, and families after the recent earthquake in their home country.
No updates this week; car is assumed to still be in transit.
7: MIT Solar Electric Vehicle Team
The team made a blog post about shipping the car out (which happened over a month ago). Their shipping tracker shows their container ship entering the port of Melbourne.
8: Punch Powertrain Solar Team
The team posted a new blog and vlog this week, describing their arrival in Darwin. The car has arrive and is set up in a workspace at Darwin High School, and the team had a beach BBQ with Nuon, Twente, and Eindhoven.
10: Tokai University Solar Car Team
No updates this week.
12: Cambridge University Eco Racing
Cambridge has been doing daily updates on their blog, which is great. Notably, the car has arrived at their shop. They're also welding in new roll bars. While I'm always in favor of safety, deciding that you need to go back and weld in new roll cages at this late of a stage is not exactly confidence inspiring... It's possible that the car is less complete that in appears from the exterior.
13: WSU Solar Car Project
WSU has posted a few team member bios up on their blog.14: UKZN Solar Car
No major updates this week, assuming the car is still in transit.
15: Team Solaris
16: Stanford Solar Car Project
Stanford made a post describing their road testing earlier this summer and their arrival in Australia. They've been spotted hanging out with Michigan and the University of Adelaide.
17: NWU Solar Car
No updates since the car landed in AU last week.
18: EcoPhoton Solar Team
No updates since last week.
21: Solar Team Twente
22: Siam Technology College
No updates since shipping the car last week.
23: MegaLux GAMF
MegaLux's car arrived by air freight in Singapore, and will complete the journey to Darwin via ship.
25: Goko High School Solar Car Team
No updates in the past week.
26: Durham University Solar Car
No updates in the past week.
27: RVCE Solar Car Team
The team is still posting sponsor thank-you messages to Facebook, but I have yet to see a photo of the car or any news about shipping. It appears the domain name for their website has been allowed to expire.
30: Team Arrow
Arrow has been posting team bios to their Facebook. They're also doing some road testing and practicing emergency roadside drills with the car.
32: Principia Solar Car
No updates in the past week.
36: Anadolu Solar Team
The team made a quick "29 days to race" post, but otherwise no updates.
46: JU Solar Team
Nothing to report since they shipped the car out.
47: Nagoya Institute of Technology Solar Car Team
No updates in the past week.
51: KIT Solar Car Project
No major updates this week.
77: Blue Sky Solar Racing
80: Beijing Institute of Technology
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| A rendering of Bejing's 2015 Sun Shuttle (image source) |
82: Kookmin University Solar Car Team
No updates after the car shipped last week.
Cruiser Class
11: Hochschule Bochum SolarCar Projekt
The team posted about traveling from Sydney to Darwin earlier this week. A second wave of team members was traveling to Darwin over the weekend. The team has also published a live GPS tracker of their location.
24: Istanbul Technical University Solar Car Team
No updates - still no word on if the car has shipped.
28: SunSpec
SunSpec posted an interesting teaser on Facebook - it sounds like they're attempting to rebuild in time for the race after the fire last month. Although the 20th has come and gone and they don't seem to have showed anything off, SunSpec commented on their own post: "...thanks to all staff in Admiralty who help us to rush out a new body within such extremely tight schedule." It's good to see a team that's not willing to give up. Best of luck, don't give up, and we hope to see you at WSC!
31: ITS Solar Car Racing Team
The team has posted a behind the scenes video showing some of the steps of constructing the car, as well as an unveiling video. A local new station also posted a video. It looks like they did a fairly extensive test drive while the car was between paint jobs.
33: IVE Solar Car
35: University of Minnesota Solar Vehicle Project
The first wave of team members arrived safely in Adelaide. They reported that they were going to pick up their car from the shipping company two days ago, but haven't posted any updates since then. Not sure if that's a bad sign or not?
38: Persian Gazelle Solar Car
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| (image source) |
40: Solar Team Eindhoven
Eindhoven chilled at a beach BBQ with Nuon, Twente, and Punch. They've posted a new vlog. They've also had a bit of media coverage.
43: Ardingly Solar Car
It's been a busy week for Ardingly. They drove the car around for a little bit, made it into the local news, and are reportedly shipping the car out tomorrow!
45: KGHM Lodz Solar Team
Lodz shipped the car late last week. The also posted a few more news stories to their YouTube page from back when they unveiled the car.
75: UNSW Sunswift
No major updates this week.
88: Kogakuin University Solar Vehicle Project
Kogakuin announced that they will depart for Australia in the middle of next week. They've also been in the news a little.
Adventure Class
6: PI Solar Car
No updates this week.
20: Houston Solar Race Team
34: Liberty Christian Solar Car Team
No updates this week - not a big surprise. The car is in transit, and the team isn't due to arrive for two and a half weeks.
42: TAFE SA Solar Spirit
No updates this week.
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