Mechanical speed controllers (from drills).

[Ellis]

Drills must have a Speed Controller of sorts... Surely, a robust servo pushing the button would be a much cheaper route than buying an ESC?

I know that moving parts inside the robot should be kept to a minimum, but, for someone with a very low budget?

This would mean a drill would give you a motor, gearbox, battery pack AND a speed controller...

Would this be feasible?

Ellis

[joey_picus]

Most cheap drills have a simple one way FET controller if my knowledge is correct, this is electronic (so no moving parts other than the trigger) but a) only goes one way - the reversing switch on the drill actually swaps the polarity of the motor around! - and b) isn't designed to handle a stalled drill motor for more than a very short space of time, so using it in a robot would probably result in magic smoke/magic stalling/magically losing the fight.

I don't know of any drills with 'true' mechanical controllers, if they do exist they may be worth looking into but to be honest for all the trouble of rigging up a system with drill triggers and servos, you really are better off (in my opinion) getting some proper speed controllers that you can reuse when you move on to bigger motors (you'll have to get them anyway if you intend on building non drill motored feathers, so it actually saves you money in that regard)

Unfortunately this robot building lark is somewhat expensive (not as expensive as the travel costs though...£150 for a return to Reading is probably reasonable but doesn't seem like it to me :P)

[muchalucha]

unless you start spending silly amounts of money on a drill , jsut to hack for a bot. The speed controller sare eather switches (so on off) or are extremely underpowered and one way . You would actually need 2 servos as youd need one to push the trigger ad one to reverse the polarity using the switch thing. This would require a micro controller to control the 2 servos from one channel and after all of that , it wouldnt work very well either. esc's are getting so cheap , unless you really go some , its gona be cheaper to et a dedicated esc . nt to mention a lot better for your robot.

[team_orr]

if you wanna go low tech go down to maplin (ur inspain arnt you, arse :P well you can get the maplin website i guess?) and get some dpdt switches (double pole double throw) and rig up a system with some servos

i seem to be saying that alot tonight :P

[Ellis]

Yes, I'm in Spain. And I don't have that low of a budget, I was just wondering if it was possible.

(by the way, the delivery to Spain from Maplins is quite cheap anyway)