Drive motor options

[Daniel]

Well my reason for switching to brushless was a bit more unusual. I took Huntsman to RoboGames 2012 and during it's second fight agaist Last Rites it had all 4 motors fail due to popped out brushes and shattered magnets. Then at our Nationals in 2012 my Vendetta failed in the finals for simalar reasons. So I chucked a wobbly at the world of complex brushed motors and went brought the brushless setup. I wanted cheaper motors that are made with less parts and smaller magnets, and therefore less likely to have mechanical failures from shock.

I chose the because NTM 42-30 750kv because on 4-cell they should hit 10800rpm. With a 10:1 reduction and 100mm wheels that is a calculated 5.65m/s. Under load it's probably half that and would therefore take 1.7 seconds to drive across our 4.8m wide arena which was simalar to my previous robot. I do all my calculations in m/s because we only drive a few meters before hiting the other side of the arena, in a few seconds, so miles or kilometers per hour isn't relatable. So 10mph sounds slow, but 2 seconds across an arena sounds decent, and it's actually the same thing.

[Liftoff]

If I had to build my own gearbox, would it be ok to use helical gears? Main reason I'd consider them is space, I could use narrower helical gears having the same contact area a wider spur gear would. But not too sure about the extra forces generated by those gears..... any one who built their own boxes used helicals, or knows of some reasons not to use them?