Would these motors work well?

[Chris230291]

Hi. new here. im planning on building an ant. i have a bunch of these motors (pics + spec below). this will be a first attempt at building an ant and i wanted to know how these compare to what people are using currently? are these a higher or lower spec? also could someone recommend a speed controller based on the spec sheet?

[attachment=0:3j0otjyx]Motor.jpg[/attachment:3j0otjyx]

Thanks for any help in advance!
Chris

PS sorry for the image size... forum wont let me load the actual size

[joey_picus]

Hiya, welcome to the forum!

Most antweights use motors that are smaller than those - 12mm Sanyo-type gearmotors from Solarbotics and Pololu - or a few robots are still on modified R/C servos. The weight of those motors (30g) could be prohibitive though, and the current draw limits what components you can use as of all the currently used controllers only the Scorpion Mini or Sabertooth 2x5A would handle that current safely, and your batteries would have to be able to provide the current as well. (also some of them are rated at 12v and above)

If you could use them with some good tyres and get within the 4 cube/150g limit though you'd have something quite powerful on your hands

P.S: I'd advise you to check the antweight forums as well, as quite a lot of ant builders frequent those and not the FRA boards (the ant events being run outside of the FRA's jurisdiction): http://www.robotwars101.org/phpBB/index.php is the place to go ^^

[Chris230291]

Awesome cheers dude. there the controllers i was eying up. anyone know how to go about building my own speed controller? had a play and to get everything in the 4 inch cube is hard (because of the weight limit) and because i want it to work both ways up. but i wont let it have me, i'll figure something out. cheers for the help and i'll take a look at 101 forums.

Chris

[joey_picus]

No probs, happy to help.

Building your own speed controllers is a topic for people far more advanced than myself I'm afraid :P it's fraught with strange electrical niggles and the need for expert knowledge (Peter Waller has built - and sells - his own controllers for his ants but he's a retired electronics engineer and winner of more trophies than any sane human being I know). In a pinch you can try using the controller boards from large standard size servos as speed controllers, with the pot either fixed or replaced with resistors, but most people use Sabertooths, Scorpion Minis, SOZBOTS boards or Peter's controllers.

Getting in the weight limit and cube is all part of the challenge in ants :P look at a few pictures on RW101 and elsewhere (http://www.antweight.co.uk/ is a good site for ant pics) to get an idea of what can be done in the limit.

[Chris230291]

cool cheers dude. looked a little on the internet about what speed controllers do and how. my old man is going to speak with his mates at work for me about making my own. he works in electronics, they make sensors and controllers for industry so might and probably will sort it for me... fingers crossed!
i looked at others and noticed they all seem to use much smaller motors than what i have (coincidentally off an upgraded machine at my dads workplace) . What makes my idea even harder is getting 4 wheel drive (via belt), whilst still making a works both ways up one. if that makes sense. im pretty sure im going to need custom electronics, but im going to look into those servo controllers that you mentioned. will they be up to the job?

Cheers
Chris

[joey_picus]

I think a Sabertooth controller will run them comfortably actually, can't see why you'd need custom electronics unless you're using encoders or want to do something else electronically advanced...the starting current for the highest draw ones is just over 3A and the Sabertooth will handle 5A comfortably on both channels.

Servo boards may work, they may not work, the main issue with them is that servos - as I've found out - are very poorly specified so you don't know the limits until you've tested them to breaking point :P

[Chris230291]

all off the shelf controllers are the wrong shape/too big with the space im left with after a good strong 4 wheel drive system. iv only drawn out shapes with the dimensions of parts ive found on the internet. iv given a few mill here and there so maybe it will go in, i dont know so i guess i should buy the bits and go from there and maybe simplify.

[razerdave]

With my 4wd antweight Baby Hell, I use 2 x Banebots 3A controllers that are sandwiched close together, they are probably the most compact controllers you can get.

[archie2000]

4wd, were in competition now