Brakes & Tyres

Brakes. They're one of the most important parts of any vehicle, although brakes waste energy they're vital for safety (they also let us go down really big hills without crashing). For this reason the cost of the brakes is not included in the limited cost of $1200 that we have for the competition. This weekend we completed fitting two caliper brakes to the back wheel, not a simple exercise at all. The bicycle frame that we fitted to mount our back wheel is designed for a larger wheel than the one that we are using, because of this the brake mount does not line up! You may have noticed that the seat stays on the bicycle frame are made of Carbon Fibre. It may be light and strong but it's not good for welding brake mounts onto! Mounting the brakes required some clever plates bolted onto the frame.

 We chose to use caliper breaks because they are easier to mount and require less adjustment than V-brakes or disc brakes. Vehicles in the eV challenge require two brakes, during scrutineering the brakes are tested to see that they provide adequate braking force.

Final adjustments

New tyres!

 Finally the new tyres arrived, we chose these tyres for their low rolling resistance, an important factor in making the car as efficient as possible.

Oscar

And Now It Can Do Turns!

Steering is a critical component of an EV. Not just for the obvious reason of turning around corners, but because it can effect your efficiency substantially. Get one piece out of line and your wheels can "scrub" when turning, giving the car a bad rolling resistance and thus making the car work harder. Which is why designing and constructing the steering gave us many headaches from brow frowning and head scratching. But it is now complete (pretty well) and so we braved the rain to take it for another spin.

The car is now fitted out with some fine steering devices

Focus

REEEOOOooowwww

Return Of The Rope Tire!

Last year our car used plain old billy cart steering, and even though it could cleverly lean the vehicle into turns, it still felt a bit agricultural. So this year we have decided to use ackerman steering (the type of steering all road cars use). This makes it harder as there are much more angles to consider, many distances to calculate, a lot of levers to account for and these strange things called rose joints. The reason why we have chosen to use this steering system is because its very efficient, if you get it right. So far all is looking well and with a bit of "trimming" she should turn true.

The steering layout with a lightweight ply-wood steering wheel

Taking the car out for a spin with a fully operating steering system certainly was a lot more satisfying and we can now see the car really taking shape. Although we have not reached speeds of more than walking pace, we can suddenly feel the potential.

Guy gettin some gnarly speed!

okay, so we didn't go quite as fast as this looks, but some crafty camera work helps

Next step - to focus on the drive train. Motors and gearboxes, should be simple?

Oscar

Rolling For The First Time

On saturday we welded on the front wheel hubs which are made from two old bike bottom brackets and cranks. The car was rolling for the first time! But we had a problem; three wheels and only two tyres! Our solution? We used rope instead of a tyre of course! (and two F clamps for steering)

Wheel hubs made from bicycle bottom bracket

Oscar- Check out that rope tyre

This guy's enjoying himself

Some Interesing Pictures

Here is an assortment of pictures from the 2009 and 2010 event aswell as some of where this years car is at.

Last years car

2009 event

Starting grid 2010

Who's the Best

Oscar getting some welding done

Latest picture of this years car

 Oscars video of testing at Mathews netball centre 2010

Our thanks go to Frank Thomas for lending us his MIG welder, cheers Frank!
We also acknowledge SKM engineering as our sponsor.

Guy