thwackbot maths

[Danjr1]

Anybody know where i can get the formulas to go from motor rpm down to kinetic energy in such a robot?

thanks

dan

[Danjr1]

Re: thwackbot maths

If a 18v motor/ gearbox runs at 580rpm, would overvolting to 24v mean it runs at 33% more? Approx 770 rpm?

[Bodge Job]

Re: thwackbot maths

http://www.riobotz.com.br/en/tutorial.html I think that has something about thwackbots...

[craig_colliass]

Re: thwackbot maths

With regards the power thwackbots have,
I would say with Seraph which is probably one of the most successful thwackbots out there at the moment,
the trick is to have as much power transmitted to the arena as you can.
the total power for Seraph is 300 watts but the power is only part of the story if your robot is skidding all over the place this is energy lost to the weapon!
Hence big wheels and bike tyres, the leaver moment is increased, and so the mechanical advantage is better than smaller wheels.
The problem with thwackbots is the issue of accuracy, you can't always get the robot to throw over the sword were an opponent is,
the best way round this is to find a big bunch of them and hit what ever you can! this accuracy problem means that sometime you loose points in fights because control looks a little erratic!
Remember the important thing is to have fun, be inventive and keep improving your design.

[Danjr1]

Re: thwackbot maths

worked out that the thwackbot design i had would have 500j max so its not really worth it

[PJ-27]

Re: thwackbot maths

500j is still a decent amount, besides Thawckbots will never have the same destructive power as spinners or moveable power of Flippers.

Everyone makes spinners and flippers, try something different.

[Danjr1]

Re: thwackbot maths

this thwackbot idea is running through my head again. what do people reakon would be the most effective way of literally bolting some kind of axe (would be a modified mattock axe) with a fibreglass handle to a box? the other end would have a wedge on hinges

[Ellis]

Re: thwackbot maths

I'd probably do it something like this:


Be careful, you may injure yourself on my epic design skills! :wink:

[typhoon_driver]

Re: thwackbot maths

you need to work out the moment of inertia for the specific design to calculate the kinetic energy.

http://www.teamcosmos.com/ke/ke.shtml

Build a thwack bot using a bar that's offset from the center and then a single tooth at the outer radius.

This will give you a rough indication of what the kinetic energy would be for a given rpm. Bear in mind that the rpm of your body won't be the same as the rpm of your wheels. You need to work out the robots tangential velocity that your wheel rpm gives you and then work out the rpm that the bot will spin at.

[Danjr1]

Re: thwackbot maths

been watching youtube vids of thwackbots, think ill give it a miss! lol