Fiest [beetleweight]

[craig_colliass]

Re: Fiest [beetleweight]

Just tried out the axe mechanism seems to work OK, will put a video on the Gabriel build diary tomorrow if I have time.

[ewan]

Re: Fiest [beetleweight]

It works! Had to make up a new clutch part but it's working brilliantly (and very noisily) now. Will make video this evening

[ewan]

Re: Fiest [beetleweight]

Current set-up:





And here's the video

http://www.youtube.com/watch?v=rSLz4u3ybk4

You'll notice the first time I brake the clutch doesn't engage - this sometimes happens when the flywheel is going slower and doesn't have enough inertia to un-jam from the bottom of the threaded shaft. When going faster it usually separates fine, but I've only tested the thing up to 30% throttle (slightly worried bits will break if it's going too fast.. and as you can see it vibrates like mad). The motor has enough torque to re-screw the flywheel down the shaft after a release (it does this twice in the video). On the final release the cable pulled free from the clutch mountings (just a couple of M3 bolts):



It's not a big issue, I'll find a harder-wearing way of mounting it in future.

All in all I'm happy with the concept. Once it's in a fully-laden chassis (complete set-up weight is currently 700g, with lots of material to remove) it should hopefully move around a bit less although I don't doubt it will jump even higher with a weighted axe-head attached (and at higher flywheel speeds..). Still need to work out a re-cocking mechanism for the axe (possibly a spring).

[gizz]

Re: Fiest [beetleweight]

Looks like it packs quite a punch! Will be interesting to se the damage once the axe head is fitted

[PJ-27]

Re: Fiest [beetleweight]

Looks awesome! Are you hoping to put this in a Beetle?

[ewan]

Re: Fiest [beetleweight]

Yeah, or rather the frame you can see will be the start of the beetle frame. Undecided yet whether to go for car steering (think original Killerhurtz) or 4WD though

[jonny]

Re: Fiest [beetleweight]

i'd go for 4wd with much less grippy wheels at the back (think 360)

[ewan]

Re: Fiest [beetleweight]

Started on the final chassis for the machine, pictured by the test-frame for reference-



Bulkheads are 8mm polycarbonate, motors are these http://www.pololu.com/catalog/product/1597, tires are these http://www.robotmarketplace.com/product ... i-3MM.html
Overall length as pictured is 230mm, final width will be around 100mm

[harry hills]

Re: Fiest [beetleweight]

wow, looking good. you sure those motors will be man enough?

[ewan]

Re: Fiest [beetleweight]

If they work as specified then yep. Importantly they fit more easily than the car steering I'd initially planned and are possibly lighter