A few queries

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Rhys
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Post by Rhys »

4 inches cubed of helium wouldn't produce enough lift would it? Someone correct me if i'm wrong, but I reckon you'd need about ten times as much. There's always Hydrogen, but thats way too dangerous for ants.
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Post by Remote-Controlled Dave »

Well, I did fink about that, I'm not smart enough to work it out. But when I asked if there was a minimum weight limit on ants, I was told "no", so you could find out how much lift you could get from a 4" cube's worth of helium then base ur ant on that weight.
But I have no idea what I'm talking about, so. lol. Just a concept.
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Simon Windisch
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Post by Simon Windisch »

An antweight cube is nearly exactly 1 dm3 volume

A mole of gas occupies 22.4 dm3

So an antweigh cube holds 0.045 moles of gas

Air weighs 28 g/mole so a cube of air weights 1.26g

Helium weighs 4 g/mole so a cube of helium weighs 0.18g

So a cube of helium (assuming no space is taken up by the robot or the containing balloon etc) will give 1.08g of lift, so if you can build an antweight weighing 1.08g you're flying! That's if I've got my maths right.

Alternatively you could keep the helium in a canister and fill a much larger balloon after the bout starts, and hopefully ascend before being attacked.

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Post by Raizor »

Not entirely true their simon.

1mole of gas occupies 22.4L at S.t.p. (standard temperature and pressure)
However we rarely see S.t.p.
At Room temperature and standard pressure you see 24L for one mole.

So lets assume that pressure is constant (which it is not immediately making the calculation invalid but here goes)

Since air has a mass of 28g/mole. A cube of Air has a mass of: 1.17g
SInce hydrogen has a mass of 4g/mole. A cube of helium has a mass of 0.17g

So making the same assumptions as simon you can lift 1g at standard pressure and room temperature.

Hydrogen is far more dangerous but could theoretically lift a whopping 1.13g :D
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Post by Andrew_Hibberd »

wihtout doing the maths to lift an 150g ant you would need about 120 4'' cubes of gas a little OTT, but if it were possible how would it work. It can't be imbolised and it would bounce of the walls :lol: . Just imagine a disc hanging from the bottom of a huge bag of tin foil :o
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Simon Windisch
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Post by Simon Windisch »

Well who would win on style control damage and aggression (assuming that's what the judges decide on)?

Floating at the top of the arena has lots of style, but I suspect no aggression or control. Neither robot would damage each other so perhaps the ground based robot would win just by showing its control and aggression to be superior; i.e by driving well and by using its weapon.

But I think we've proved that it's impossible to get enough lift with hydrogen to fly an antweight. Perhaps it's time to go back to the hovercraft idea?

Simon
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Post by Remote-Controlled Dave »

Wow, what have I started? :-?
Just to cap then, in theory it wouldnt work, unless you fill it from an external canister upon "activate".
Thats that covered.
Hovercraft then!
Or my other idea could set off some debate - an antweight snake? Articulating tube? Any thoughts on that one?
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Post by Bigshot team capt »

I personally wanna try the hovercraft idea. Only problem would be if u got flipped....
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Post by Remote-Controlled Dave »

Another quick querie: I now have a full body spinner that spins for defensive purposes only, not for attack. Would it still be banned from non-spinner combat? Cause if so I'll make it interchangable. Ta.
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Post by Simon Windisch »

We have non-spinner combat for two reasons... firstly so that we can have battles early in the day and not get damaged, secondly so that we can battle without a battlebox. I don't know about offensive/defensive but would you say you could fight without causing much damage and that your robot is safe without a battlebox?

Simon
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