FeatherW help/parts

Hi Jon,
I don't know if you have sorted your weapon yet, but Gary makes a very good suggestion. If you wanted to use a screw thread, you could consider a car jack. About the easist and cheepest thing to get hold of and it has suitable thread type (and obvious rated to reasonable forces [for a feather anyway]). I used one for the original Tiberius (heavyweight). Only down side is you only want to use the threaded bar in tension, whereas linacs are ok in either so it depend if this fits with your your design.
Working out the 'ideal' axial force of a screw thread should be fairly straight forward.
U'll need to know the pitch of the thread (usually roughly 3mm) and input torque to the threaded bar.

good luck
Sam

ah thats good to know about the bat, something i know very little about to be honest =). I was thinking I would need two packs, but I imagine the two new bats supplied with the drills, broken down would give a 36v pack, wouldn't need that much would I? (apologies if these are simple stupid questions =)
lol love the circuit diagram =P

To sam, yeah i was looking at using a jack, was playing around earlier today at uni with some threaded bar and a N test gauge got a 44N pull of a 18v drill before it started spinning in the chuck, was told 'under pain of death do not damage the chuck' by our tech guy =). Copying the idea on a smaller scale or getting a small jack would defiantly provide more than enough force.

Hopefully however I think the search for an Actuator is over. should know by tomorrow which is great!

Would anyone happen to know the width of the robo challenge wheels was looking on google but could only find dia. Also if anyone is selling a set of 100mm let me know will be very happy to take them of your hands =)

Sounds like a pretty mundane piece but was wondering if there are any caster ball makes/types that people would recommend?

Cheers
Jon

hi, the blue wheels are 30mm diameter i beleive :)

Yeah.....they're more like 30mm wide :crazy: :)
That's for the 100mm diameter wheels anyway, and I believe the 75mm ones are around 23-25mm wide

oops! meant to say width :crazy: thanks jamie

Yeah I figured it was just a typo :)

Quote:

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Sounds like a pretty mundane piece but was wondering if there are any caster ball makes/types that people would recommend?

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Hi Jon. To be honest, I'd recommend going for none. With castors, unless they're pretty industrial (therefore heavy) they won't really survive robot combat and will likely get damaged beyond useability (did I just make that word up? :shock: ). Ball transfers units are a more robust alternative but they can get clogged up with bits of crud from the arena, or dirt and gravel (if you test/run your robot outside) which results in them becoming much rougher and, generally, crap.

I've always found that a simple skid pad or two, fitted near the leading edge and made from a piece of low-friction plastic or similar, does a sufficient job and is easy to mount and replace if damaged. Cost is almost zero, just requiring a small offcut of material and a bolt or two to hold it on.

You get to this in uni? Man, the nearest I got was a remote control power switch...

Anyway. Advice:
Print out all the rules- you'll refer to them a fair bit.
Skim through the Rio bot tutorial. Good advice if a little long winded

As for the controller, surely you'd get the similar amount of marks if you just explained WHY you chose not to attempt to building your speed controllers (with the knowledge of how it works) compared to spending the building something that will just blow up and take money with it. It's not the best engineering decision I grant you but it is the best project management decision you could make. If possible, have a quick chat with Ian - he can't make your decisions for you but even his evasive efforts should tell you where the marks lie.

I'll keep reading- good luck!