Over and Under or around the sides

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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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new car name = spot

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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OK, I've just got back from the circuit. It was our first race of the season today the Corporate Challenge.

We were using it as a shakedown really blow out some cobwebs and learn as much about the chassis as possible so old body etc.

We started relatively low down, placing is done on a first come first served basis on entry. So we were 34th, steadily we climbed throughout the race to about 7th then after the first stint (2hrs) the second driver hoped in, about three laps in to their stint a car nudged the back of us, spun us around threw the car on to the grass causing it to roll over 2-1/2 times.

The driver was unhurt just a bit frustrated, we were on target to beat our previous 4hr mileage record by approx. 20miles with an under geared car that is still awaiting it's new body.

To be honest, the whole incident has left me feeling a little disillusioned and I'm not sure what our next step will be. I know this sort of thing happens in F1 every race but when you do it all out of your own pocket it becomes a very different story.

Only time shall tell....
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jon-mullen
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Joined: 10 Sep 2008, 02:56
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Re: Over and Under or around the sides

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Glad your driver's ok, but that really blows. I get 'a bit frustrated' just driving around on the street, I'm pretty sure I'd start swinging if somebody wrecked me in a car I'd built from scratch. :evil:
Loud idiot in red since 2010
United States Grand Prix Club, because there's more to racing than NASCAR

BreezyRacer
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Joined: 04 Nov 2006, 00:31

Re: Over and Under or around the sides

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So let me see .. you passed 27 cars in 2 hours. I would be quite happy with that aspect of things. As for the nudge, spin, and flips, were there an apology or penalties enacted? The roll overs do make you consider all the work you're putting into the new body. Maybe it doesn't have to be so nice ..

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flynfrog
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Re: Over and Under or around the sides

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what was the damage total?

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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I've finally managed to pop back home to assess the damage.

4 buckled wheels,

written off body - but as you all know we were working on one ;)

wrecked roll bar, but, I'd rather it do it's job and be visibly unusable than appearing fine but actually being unfit for purpose, this way there is no choice but to change it.

SO that's the latest sit-rep I'll try and keep you all up to date!

[EDIT]

Here's a quick bit of video to give you an idea of just how fast we were going

http://www.youtube.com/watch#!v=bZuL0Nuut34
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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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greenpower dude reloaded wrote:I've finally managed to pop back home to assess the damage.

4 buckled wheels,

written off body - but as you all know we were working on one ;)

wrecked roll bar, but, I'd rather it do it's job and be visibly unusable than appearing fine but actually being unfit for purpose, this way there is no choice but to change it.

SO that's the latest sit-rep I'll try and keep you all up to date!

[EDIT]

Here's a quick bit of video to give you an idea of just how fast we were going

http://www.youtube.com/watch#!v=bZuL0Nuut34
best of luck mate.

tok-tokkie
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Re: Over and Under or around the sides

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This has been a very interesting saga. Being a true saga it has its low & high points. Best wishes for the recovery & a high point looms ahead I suspect.

BreezyRacer
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Joined: 04 Nov 2006, 00:31

Re: Over and Under or around the sides

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Is that video in real time? It looks pretty fast . much faster than I thought it would .. looks good!

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
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Re: Over and Under or around the sides

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Yeah, it is actually real time, it is a really quite quick vehicle. It was going a couple of MPH faster when it rolled.. The batteries were fine to have lasted at least another 15-30mins I would have thought and so we were running considerably under power and on target to place about 6th agaisnt everybody else that was running at 100% power.

We use the Corporate Challenge as a test session really where as virtually everybody else is "balls to the wall" going for it.

The new body should roughly halve the drag still so we should be really fast then!
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BreezyRacer
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Joined: 04 Nov 2006, 00:31

Re: Over and Under or around the sides

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greenpower dude reloaded wrote:Yeah, it is actually real time, it is a really quite quick vehicle. It was going a couple of MPH faster when it rolled.. The batteries were fine to have lasted at least another 15-30mins I would have thought and so we were running considerably under power and on target to place about 6th agaisnt everybody else that was running at 100% power.

We use the Corporate Challenge as a test session really where as virtually everybody else is "balls to the wall" going for it.

The new body should roughly halve the drag still so we should be really fast then!
With that much speed are you having to slow for corners at all? Are you braking on a typical lap? Can you "draft" other vehicles for more speed (I mean does it show an improvement to draft)

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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There is typically no braking at all unless you're pitting. You do come off the power a bit momentarily through the chicane.

Josh, had been drafting a couple of cars very closely, he was probably about 500mm behind the LOLA assisted vehicle for a while. He caused them to push too hard and run out of battery hehe..
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BreezyRacer
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Re: Over and Under or around the sides

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This might be getting into a bit of proprietary info but do you get more overall energy out of a battery thru constant, level discharge, or by pulsating the discharge, or do you guys even think/test about that? .. or maybe no comment?

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flynfrog
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Joined: 23 Mar 2006, 22:31

Re: Over and Under or around the sides

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I cant speak for GPDR but in solar racing it was usually better to drive a constant speed rather than a constant power. I know this doesn't exactly answer your question. But in general you want the min amount of power to drive a certain speed. The motor controller does this by the length of pulses for each phase.

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greenpower dude reloaded
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Joined: 29 Dec 2005, 20:03
Location: Portsmouth, UK

Re: Over and Under or around the sides

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We run at a constant current, or very close to probably +/- 1 or 2 amps. I'm currently working on my own datalogger to try and monitor power usage a bit better.

You are right Flyn with the nature of an electric motor it's much better to run at constant speed (i.e. change up a gear to go uphill :D) but when on track we quickly get to the point where that all levels out.

We don't however have a speed controller.

Being essentially just 2 sometimes three people that contribute towards the car in different ways I never really get much chance to test anything like that, but we've got a few bits and peices we're looking in to. 8)
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