ARC Robotics: Big Dave's Little Brother

As several of you know, and some of you follow, ARC Robotics (Ali, Rob (that's me!) Chris) are building a heavyweight 'bot for Robot Wars, affectionately called Big Dave 3 - all of his progress is over on the ARC Robotics website, www.arc-robotics.org.uk. We've also decided to wander into the featherweight arena with our next build - Big Dave's Little Brother. We're hoping to do all of the 2018 Extreme Robots events.

This is going to be a slow, slow build - Big Dave and the rest of life is going to take priority unfortunately! This thread will be updated as and when I do the design, bits arrive, etc.

To this end, I've been sketching out the outline of our feather, along with compiling a parts list etc. Very much inspired by the beautiful Omega (http://www.fightingrobots.co.uk/thre...s-build-thread).

Wedge, meet drum.

Attachment 6404

The party piece is, of course, the big spinny death wheel at the front. We're planning to drive it with a TP4260 motor, the baby brother of what is in Big Dave, via a two groove 3V V Belt, 2:1 reduction. I've also got the choice of gearing down 5:1 with the use of a different motor winding and a custom machined pulley. But that adds cost - and a lot of it. The wheel itself will hopefully be in the 5500RPM range, with a tip speed of 122.5MPH. Aiming to break the 10KJ mark.

Drive is done via a 4:1 reduction via bevel gears to 4'' wheels. Leaning towards the Turnigy 5045/500Kv outrunners at the moment. Aiming for a 13MPH top speed, but I'm also tempted to gear down even lower to get a bit more pushing power. The wheels will be driven together with the help of some HTD5-15 belt.

Battery wise, I'm hoping that we can run all of these off of one of Big Dave's 5000MaH batteries.

Size is 500x400x100. (L,W,H)

Things I'm worried about: weight, pushing power and controllableness. (Is that a word?)

Critiques are most welcome - this is just a side project of a side project at the moment, so nothing is set in stone.