G'day again guys from Oz. Been watching with interest at some of the new car designs and thought I'd share a couple from my schools from our eV Challenge competition here on the west coast of Australia.
These are the two cars we raced in November last year. Compared to the Electrathon rules our cars are quite a bit shorter (in 2013 we were only allowed to be 2400mm/roughly 8ft long, in 2014 we can go to 2700mm or 9ft) and only have 432Wh (36V 12Ah for example) of battery capacity, although in our open class we can use LiPO. For this year we can run a 36V 16Ah LiPo however. Both cars are wooden monocoques and needed to be finished off but we ran out of time. #53 was unsurprisingly called Herbie!
Hope you like them! www.facebook.com/PerthElectricVehicleChallenge
Very cool looking cars. Almost like the stock cars or funny cars that are full sized gas cars raced in the US
Did they get sponsored by Nissan or just like the cars?
Do you guys run for a full hour on the smaller battery pack?
With the full body and the open front but closed rear does it have more air drag?
Is the frame all wood or is there a metal frame with wood for body and other supports?
Most of the cars in the NW race area are from 6 feet to 9 feet long. There are only a few that are longer, like the ones made by Dave Cloud. So even though the rules allow most of us make shorter cars.
In the US the roll-bars would need to be wider and probably more over the driver's head to be legal.
Thanks for sharing,
Mike
Glad you like them. The Nissan sponsorship was from a local dealer. They supplied us with a leaf plug in electric car as our safety/pace car as well which was cool.
Yes the battery pack does need to last the hour so obviously they run a bit slower over here than your cars - longest distance we've had on a road course (i.e. non-oval) is about 35km or 20 miles approx. This year with the bigger packs we should go quite a bit further and faster. We also require a minimum of 3 drivers over the hour, each doing roughly 20 minutes each, so distances are down anyway as we have to do at least 2 pitstops costing us time.
As you can see the wooden structure is 3/4" inch formers and longerons with a 1/8" marine ply body - a bit like a wooden kayak or the Mosquito bomber from WW2. We used steel for the rear subframe (which also doubled as the roll bar and supports) and the front axle.
Hopefully you can see from this photo that the high nose was simply used to direct air around the central keel which carried the driver's backside and the batteries. We designed the concept on similar lines to solar cars with their high bellypans to reduce the floor area close to the ground which would generate turbulence with the ground. However the central keel would still allow us to get the heavy items - diver, batteries, and the rear wheel/subframe/motor low in the chassis for good handling. Jury is out if it worked as we ran out of time to put a canopy on the car so the aerodynamics were compromised anyway.
We had 50mm clearance over the driver's helmet with the roll bar which was the minimum required. Hope fully that would be enough!
Out of interest what are your cars doing distance-wise on a road course Mike?
Hope this gives you a bit more info - check out some of the other cars at the facebook page.
Cheers
-- Edited by Clay on Wednesday 28th of May 2014 10:19:49 PM
This shot from 2012 with our 2013 #7 car unpainted might give a better idea about the underbody aero we've been tyring.
Obviously the open ****pit and exposed wheels do make a lot of the underbody work redundant however we think it has some potential. But it does make building the cars way more complicated compared to a flat floor car like our 2011 car below
That car was a basic 3/4' tube steel chassis with alloy panels pop riveted on.
