Alot of stuff to fit in a small space.

Hi. Im on with getting everything sorted for my bot Hooligan that i have entered into the Huddersfield event. I only have a small amount of space inside the robot(Inside dimensions: 467 wide X 275 long X 50mm high). I have to fit 4 drill motors with the 75mm wheels attatched, 2 electronize speed controllers, Radio gear and a battery plus all the wiring. is there anything i should try avoid putting really close together? its made so that everything will only just fit inside, whats the closest you would risk putting speed controllers to the motors? and whats the closest you would risk putting battery to the motors? i have an ok sized space for radio gear.

Batteries can go as close to motors as you want. There is about 4cm between my motors and batteies and it has always worked fine. Speedos, again, in my bot, fairly close, but its enclosed in a box thats coated in an EMF-reducing material. I would avoid putting the RX close to the motors if you can help it, but if youre running a spektrum it matters not-a-jot. The motors cause interferance to the RX, not the speedos, so they can go fairly close.

My small FW is 280 long, 355 wide and 83 high, and if my bot was a different shape I could fit those parts in, but it would be tight :) Do you have a picture of what your bot will look like?

Yeah like Dave says, suppress your motors with capacitors accross the terminals and you should be ok. The main problem you will have is that others dont suppress motors, ie people on 2.4ghz dont suffer the same effects so they dont bother.

DB5 has motors speedo and batteries in a space no more than 220x150x80mm should be fine.

ill get a pic. havent got a clue about this suppressing motors thing. sounds good tho :p .
cheers.

Basically take a small capacitor, around the 1 nanafarad level (if I remember correct) and connect it across the two motor terminals. Generally soldering works best with drill motors.

Doing this reduces the sparking that you get when the motor initially starts up or changes direction quickly. This sparking can cause a lot of interference if you are running a 40 meg set, not such a problem with 2.4Gig.

Like these?
http://cgi.ebay.co.uk/50-x-1nF-0-001uF-Ceramic-Disc-Capacitors_W0QQitemZ250164170659QQcmdZViewItem?_tr ksid=p3286.m20.l1116http://cgi.ebay.co.uk/50-x-1nF-0-001...QitemZ25016417 0659QQcmdZViewItem?_trksid=p3286.m20.l1116

Yes.. theyre the sort of thing you want ... 10nf might be better.

There is a page on this site about interference prevention.
http://www.fightingrobots.co.uk/documents/emi.pdfhttp://www.fightingrobots.co.uk/documents/emi.pdf

http://cgi.ebay.co.uk/50-x-10nF-0-01uF-Ceramic-Disc-Capacitors_W0QQitemZ260276003015QQcmdZViewItem?_tr ksid=p3286.m20.l1116http://cgi.ebay.co.uk/50-x-10nF-0-01...3286.m20.l1116
Do i have to open my motors up and attatch it inside or can it be attatched to the terminals that stick out from the bottom of the motor?
and whats this EMF reducing material? is it the same as aluminum EMI shield tape you can get for guitars?

Cheers for the help guys. btw if its an internal capacitor is there a chance the motors could already have one in? i got them from ewan gimson robotics shop about a year ago.

(Message edited by xtreme on August 24, 2008)

Capacitors go on the outside, between the terminals. As for the coating, Im not sure what it is, I got it off an engineering buddy of mine

Cheers fella

The EMF shielding material can be anything that conducts electricity. Even an ali/zink pain spray.

Its based on the fact that a Faraday cage is EMF nihilating.
And a Faraday cage....
http://en.wikipedia.org/wiki/Faraday_cagehttp://en.wikipedia.org/wiki/Faraday_cage