The previous post recounted Illini Solar Car’s journey from Melbourne, Victoria to Darwin, Northern Territory. Once in Darwin, Argo underwent pre-race inspections, know as scrutineering, and preparations for the race. The team was in Darwin from September 28th until the beginning of the race on October 8th.

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After obtaining our garage space in the Hidden Valley Motorsports Complex, we went to work assessing the damages on Argo and making small fixes in order to prepare the car for some track runs. The electrical team was plagued with battery management issues that took a few days to work through, with extra parts from Stanford's team, but after that the car was running and we went straight to the track as soon as we could. On October 2nd we joined all of the other American teams at a barbecue hosted by Michigan Solar Car. The other teams at the track were very generous and helped us out when they could, so we felt welcomed into the solar car community.

Work in Garage

October 3rd was mostly track testing at Hidden Valley. We reached top speeds of 75 km/h and both drivers got used to handling the car around the track as well as the figure-8 course. Then we spent some time preparing Argo to pass static scrutineering which took place the following two days.

Argo departed for static scrutineering a little after noon in Darwin on October 4th. The first round took the entire afternoon but we only had a few minor issues to fix in order to return and be re-scrutineered the next day. On the way out of the convention center where they held scrutineering, our trailer got a flat, but thankfully NIT solar was there to lend us their jack.

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We returned to static scrutineering the next day after making the minor adjustments, and our electrical system and batteries passed inspection! We were relieved to be closer to moving on.

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The morning of October 6th we got the last needed green dot to clear static scrutineering! Later that day we also finished the figure-8 part of dynamic scrutineering with a blazing time of 13.82 seconds. That’s 4.18s less than the requirement and was the fastest time run of any team there! Needless to say we were pretty excited.

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For dynamic scrutineering on October 7th, Argo was required to pass hot lap, slalom, and brake tests along with the previous figure-8. The warm-up for the hot lap went smoothly, but during the timed run around the track, connection issues stalled the car. Fortunately, the driver was able to reset it and drove the rest of dynamics with one out of two motors running. We easily passed slalom and brake tests and received our special 50th anniversary World Solar Challenge license plate.

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Finally, on the morning of October 8th, we joined 37 other teams from all over the world to begin the drive 3000km down Stuart Highway. Scrutineering had tested our strengths and weaknesses as a team and we felt ready to start the challenge.

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*You can view more pictures on our Flickr album. Follow us on Facebook or Twitter to get more updates from us! 
The Bridgestone World Solar Challenge 2017 ended around 3 weeks ago. It was the first race our team has ever participated in. We were very fortunate to have very supportive sponsors who made this possible. With this post (and more subsequent posts to come), we hope to give everyone a glimpse of what it took to bring Argo 9670 miles across the ocean from USA to Australia and 1860 miles across the Australian outback.

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Part of the team arrived in Australia on the 20th of September, 6 days before the garages at the Hidden Valley Motorsports Complex became available for all teams.

Due to various reasons (the main one being the lack of time to look for a logistic company who could ship Argo to Australia within a month and charge a reasonable cost), we had decided to ship Argo and a pallet of our stuff to Melbourne. A company would then help us to clear everything through the customs and bring them to a storage space nearby.

We had expected Argo to be sitting at the storage space waiting for us prior to our arrival, but of course, nothing in the real world goes according to plan.

Fortunately, after some phone calls we managed to have some quarantine officers inspect the crate and pallet 2 days later on the 22nd of September and (surprisingly) we passed the inspection smoothly!

The first look at Argo nearly gave us a heart attack.

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Argo was damaged during the transit. Some bolts on the suspension assembly were broken and one of the ratchet straps holding down Argo was nearly broken. We did some further inspection on Argo but did not find any other visible damages.

We had to make a decision: to switch out one of the worn out suspension parts (would have taken half a day - it was on a Friday afternoon so that meant having to wait until the next Monday before we can do anything), or to just replace the broken bolts and strap Argo on a trailer anyway and head for Darwin.

We took a leap of faith and decided to just replace the broken bolts and trailer Argo to Darwin. Losing 3 days would mean not having enough time in the Hidden Valley to prepare Argo for scrutineering and the race.

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On the next morning we packed everything and started the long drive towards Darwin.

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(We clearly overestimated our packing skills.)

We naively thought that cling wrap and some tapes were enough to protect Argo throughout the journey to Darwin. The wind in Melbourne had proven us wrong. (It was even windier than Chicago!)

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10 minutes into the journey, after making multiple wrong turns and having some radio communication issues with other vehicles in our convoy, we pulled over in a residential area and added some tarps over Argo.

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We had to stop countless time on that day (and on the subsequent days) to re-strap the tarp due to the wind.

On the third day we finally made it to the outback. It was less windy there, and we passed by the Minnesota solar vehicle team! They were test driving their solar car across the outback. It was very exciting for us to see a solar car there for the first time!

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With the A/C at full blast we were still sweating in the car. It was 42C, or 107.6F out there!

As we exited the Southern Australia territory we also had to dispose of all fresh fruit and vegetable in a quarantine bin to help keep fruit flies out of SA.

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The speed limit increased from 110km/h to 130km/h as we entered the Northern Territory!

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On the 28th of September, which was two days after our scheduled arrival, we arrived in the Hidden Valley Motorsports Complex and were greeted by many other friendly teams!

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Each team could choose to have either a permanent garage space or a temporary space in a tent - we almost wanted to pick the latter and work at our Airbnb but chose the former in the end. Glad that we made that choice because we had a great time interacting with all other teams also in the complex!

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That concludes our arduous journey from Melbourne to Darwin! The trip was actually really helpful for a zero-experience team like us. We got to experience what it's like travelling in a convoy, passing a roadtrain, camping by the side of the road, not showering for multiple days, etc. We also got to learn about the various defects of our radio equipment which had later caused a ton of issues during the race.


*You can view more pictures on our Flickr album. Follow us on Facebook or Twitter to get more updates from us! 

Meet Argo, Illini Solar Car's first vehicle! Three years in the making, Argo is also the first solar vehicle from a University of Illinois team since the Photon Torpedo in 1997.

Argo's body design is catamaran style - a design which has become the traditional solar electric vehicle shape. It features a five fairing design: four for the wheels and one for the driver in the center.

Argo's structure is a semi-monocoque design, which means that the carbon fiber body and the carbon fiber sandwich panel chassis are structural parts of the vehicle. The only metal parts on the vehicle are the roll cage and suspension arms. This significantly reduces the weight of the vehicle.

Argo is a front wheel drive vehicle with the 16" tires on carbon fiber rims being driven by in-wheel electric motors. The on-board lithium-ion battery pack can hold over 5 kilowatt hours of energy, which the 6 square meter silicon cell solar array charges. Additionally, regenerative braking allows the vehicle to regain energy while slowing down.

Bringing Argo from the North Quad to the Bardeen Quad
Team members at the University of Illinois built nearly every part of Argo. This includes the solar array, which we fabricated in the Electrical and Computer Engineering Building's Clean Room and Open Lab facilities. In addition to the facilities provided by the ECE Department and the Engineering Design Council, the completion of Argo would not have been possible without the generous support of all our sponsors!

The next stop for Argo is the 2017 Bridgestone World Solar Challenge in Australia. The vehicle left the University of Illinois on Wednesday and will arrive mid-September ahead of the October challenge.

After the World Solar Challenge a slightly modified Argo will compete at the 2018 American Solar Challenge. Look for more posts soon about the creation of Argo and its journey to Australia!

Argo on the North Quad

This September and October our team will be heading to Australia for the World Solar Challenge. This is our first time participating in a race and we are very excited to meet other teams and drive through the Australian outback!

Thanks to the help of Renee from the UMNSVP team, we managed to sort out the logistics of getting the car to Australia even though we didn't have much time left.



This was two nights before Argo was brought onto campus from our workspace. We were doing a pre-flight test, which involved testing the functionality of the lights.


In the afternoon before the car was shipped out, we loaded the car onto a trailer to bring it from our workspace to campus, as the ECE Department had very generously agreed to let us use their loading dock.
Thank you Bruce for helping us to move the car!


Unloading the car from the trailer at ECEB involved a spare tire and some muscles. The ramp was too steep and the ground clearance of the car was too small so we couldn't just roll the car down.


While figuring out how to make the tight turn into the loading dock, it started to rain. We were being paranoid about water leaking into the car, although the mechanical team leader repeatedly assured us that the car would be fine. (We checked the car afterwards and it was indeed fine!)



We (and the car) were taking a shelter in a narrow walkway outside ECEB while part of the team figured out how to move the car to the loading dock. We had thought of putting the car on dollies but it just slid off the dollies. We ended up having to remove a post and sacrifice some bushes in order to bring the car in.


Roughly an hour later, the car was finally sitting at the loading dock.

Thank you to Scott and crew from machine shop for helping us to move the car and staff from the business office for your support. We couldn't have done this without you!


Before packing Argo into the crate, we drove it around campus.


Here's a video of Argo on the Bardeen Quad!


Argo looked so beautiful under the evening sun!


Crossing Springfield Ave.


After taking loads of pictures, we brought the car back to the loading dock once again, although it was much easier with new dollies that we'd just bought.


We spent all night on the loading dock to pack numerous supplies and the car into a pallet and a crate. That included cleaning every bit of sand/soil/dirt from the car so that it won't get steam cleaned while passing through the Australian customs - we heard that they are very strict about this!


Putting the car onto the crate


This was almost everything we packed to Australia!


We then wrapped the car...


...and built the first wall of the crate...


...and the second wall...


...then the third wall...


...and the last wall.


Last glimpse of the car before seeing it again in over a month!


The huge crate sitting in the loading dock.


This was how the pallet looked after it was wrapped.


Scott from the machine shop helped us again to forklift everything into a 53' dry van. Thank you Scott!


Argo finally departed! Thank you Clint and everyone in the receiving office for helping us!
Special thanks also to one of our newest sponsors - Ameren Illinois - for helping to fund shipping and other race costs!


Ending this post with a picture of our team and Argo on the North Quad.

Thank you again for everyone who has helped out, we can't wait for the #BWSC!

One of the largest sub-teams we have at Illini Solar Car is our Solar Team. Our Solar Team is responsible for the fabrication, testing, and mounting of the the vehicle solar array.

The solar array team is made-up of students from several engineering majors with Materials Science and Engineering having the largest representation.  These students are currently hard at work fabricating each of the 20 modules that will be put together to form the array.

The array is primarily put together in the ECE Building Clean Room with encapsulation taking place in the ECE Open Lab. Read below for a more detailed look into this process!

The Process of Creating a Solar Module:

There are four main components that go into creating a solar array:
  • Top Film 
  • EVA Film
  • Solar Cells
  • Back Sheet
Thank you to Isovoltaic for donating EVA and back-sheet and to Sunpower for giving us a discount on Solar Cells!

The process starts in the Clean Room in the ECE Building.

Each solar module is put together on a large stainless steel sheet. This sheet is first polished and then cleaned with Acetone and IPA (Isopropyl Alcohol). 

After the metal sheet is cleaned, top-sheet and EVA are cut, cleaned, and placed on the stainless steel with top sheet on the bottom (the array is assembled upside down).

The top film is the clear outer polymer layer which acts as a shield from the outside world. Most commercial solar arrays utilize thick glass or plastic sheets as this outer layer. Solar vehicles, on the other hand, utilize top sheet to reduce weight and allow the needed flexibility for mounting the cells on the slightly curved vehicle bodies. 

Underneath the top sheet is the EVA film. EVA is ethylene vinyl acetate - a copolymer material. Upon encapsulation the EVA melts and essentially laminates the individual solar cells. This protects the solar cells from dirt, humidity, and other contaminants. Additionally, EVA helps to absorb shocks from objects that may hit the solar array (such as a rock kicked up by a leading vehicle).

Cutting the Top Film

Once the top film and EVA are cut, cleaned, and placed onto the stainless steel, each solar cells must be cleaned. Each cell is rinsed with acetone, IPA, and deionzied water and then dried with pressurized nitrogen gas. 

Washing Solar Cells in the Clean Room


Drying with nitrogen gas
Rinsing with deionized water
After the cells washed they are laid out correctly for that specific module. There are 20 modules on the car - many of which are unique in some way. Modules are different shapes and have connections at different places due to constraints at different locations on the car. This module is a 4 x 6 module with a simple internal routing (zig-zag from one end to the other). Other modules, however, may not be rectangular or may have complex or inconsistent routing to fit their connections to the car.

Placing the last cell of a 4 x 6 module

The module is next transferred to a different room within the clean room for soldering. Soldering is the most involved process of each module. Each cell has multiple connections to solder together. Additionally, the solderer must verify that cells are lined up correctly to ensure the module works as expected. Once the module is encapsulated nothing can be changed. One bad connection will render a module unusable on the vehicle. On a 4 x 6 module, like the one above, one bad connection will result in no output from 8 of the 24 cells.

Soldering in the Clean Room

The soldered cells are then arranged back onto the top film and EVA as before. The last piece is the back sheet. The back sheet protects the wiring and the backs of the cells when the module is mounted onto the car. It also acts as an insulator since the body is made of carbon fiber - a conductive material.

Now the module is fully assembled and it is transferred back to the ECE Open Lab where the module is encapsulated. The encapsulation process involves placing the module under heat and pressure. First, breather material is placed on top of the module and the module is sealed inside vacuum bagging. Then a pump is attached to increase the pressure to as close to 29.92 Hg (inches of Mercury) as possible. We are able to reach levels above 28 Hg. Lastly, plywood is clamped down on top of the vacuum bagging. Together these provide the pressure and ensure the module is encapsulated flatly.

Thank you to Airtech for donating the vacuum bagging materials!

The module is placed underneath the plywood while encapsulated
To heat the module, silicon heating pads are used. The heating pads are the red/orange pads underneath the stainless steel. The pads are incrementally increased to 135° C over the course of 30 minutes. The temperature is then left at 135° C for 60 minutes. The module is then left to cool (which can take a while). Once it reaches a temperature below 40° C, the vacuum and plywood are removed. Once cooled to room temperature, the vacuum bag and breather are removed and the module is complete!

Removing Breather Material

Flipping over the module

A completed 4x6 module!