www.robowars.org

RoboWars Australia Forum Index -> Technical Chat

Electromagnetic interference dampaners
Goto page Previous  1, 2

Post new topic   Reply to topic
  Author    Thread
Totaly_Recycled
Experienced Roboteer


Joined: 15 Jun 2004
Posts: 1346


 Reply with quote  

Yep i like to use the 3 cap system as well (when i can get them,)..some sites advise not to conect the caps to the motor body ... so there is also a lot of contraversy about how to conect caps for noise supresion

Post Mon May 30, 2005 9:54 am 
 View user's profile Send private message
timmeh
Experienced Roboteer


Joined: 20 Jul 2004
Posts: 2523
Location: Victoria


 Reply with quote  

quote:
Originally posted by Spockie-Tech:
I thought you were on 36.430 ? Didnt you have a clash with George ?

Anyway, I've put you down as 36.470 which is clear of any Vic's, but looks like Jeff Johnson (Giant Robo) in NSW is using, so if hes still using that (Jeff ?) then be aware when competing interstate..


I have both but george allso uses 36.430 so i switched to 36.470 unless i come up against giant robot then ill put the 36.430 back in.
_________________
Tim Team Reaper.

Post Mon May 30, 2005 12:11 pm 
 View user's profile Send private message Send e-mail
Spockie-Tech
Site Admin


Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia


 Reply with quote  

quote:
Originally posted by kkeerroo:
One thing that was missed about placing the capacitors across the motor brushes is to also solder two more caps, one from each motor terminal, to the case of the motor.


I do that on my own motors, but apparently there are some differing opinions on whether its a good idea or not - some say its better with the single cap, some say its better with three, and some have said that 3 *is* better than 1, but not by much, so its not worth the effort unless you are really having trouble and have tried everything else. In any case, explaining how to solder capacitors in a delta configuration (and making sure you dont inadvertertently ground the brushes if you arent careful with insualting the cap leads) was a lot harder than just saying "solder a cap across the brushes" without a digram so I skipped it.. Wink


quote:
I've seen this stuff explained on heaps of web-sites. Doesn't anyone read this stuff or am I the only one interested in rf noise suppresion. Confused )


Well, I'm personally interested (up to a point), but from what I've seen so far, I think most people's interest is probably limited to "how can I improve my radio range ?" and their attempts to visualise an invisible energy that often appears to operate by no apparent logic are probably naturally limited unless they happen to be an radio/electronics enthusiast as well as a bot builder..

I agree, The radio stuff has mostly all been said before on other sites, but thats true of nearly all the common problem solutions in robotic combat, but since new people are always getting involved and may not have done the research those who have been doing it for longer have, if you're feeling chatty, most people dont mind explaining it again to newcomers..
Smile
_________________
Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Post Thu Jun 02, 2005 1:51 am 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Glen
Experienced Roboteer


Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect


 Reply with quote  

i read that the reason the 3 caps arent reccommended is when your using metal mountings to hold the motors down. i guess its plasusible seeing as though your basically attaching the motor leads to the metal chassis (by using metal mounts). not sure if it would have any effect though and i cant see what advantage it could have over say one cap myself..
_________________
www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Post Thu Jun 02, 2005 4:50 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Glen
Experienced Roboteer


Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect


 Reply with quote  

couldnt find that interference thread so ill say it here...

finding a solid aerial/antenna thing for the reciever is really annoying me now, and i just had a thought. could i just get a spare telescopic 29mhz transmitter aerial and screw that onto the robot? logic would say that it should work fine..

do you think it would?
_________________
www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Post Fri Jun 03, 2005 9:53 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Spockie-Tech
Site Admin


Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia


 Reply with quote  

Radio has nothing to do with logic from what I can tell.. Razz

In all honesty, it probably has, but I dont understand it all that well, so it seems like a black art to me..

As far as your telescopic antenna goes (assuming you mean the sort commonly used on cars aerials), electrically, it should work as well as an equivalent length of wire would, but I wouldnt expect the sleeve-join spots to stand up under any sort of impact.

Even driving the bot into something solid at a reasonable speed would probably be enough to snap the cheaper thin-wall variety.

Piano-wire, or Mig-welding wire, or some other thin, flexible and tough piece of wire would probably be a better option.
_________________
Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Post Fri Jun 03, 2005 10:02 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Glen
Experienced Roboteer


Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect


 Reply with quote  

i was thinking of exactly the same type that comes with your normal robot radio transmitter. i was planning on just mounting it horizontally with some standoffs. that way its a metal perfect length antennae that i can just replace.

but i just read a little item on the RFL forum minutes ago that ive started doing just now on cobras old body. what the guy did was to isolate the hammer arm with rubber standoffs then used the hammer arm itself as a radio ground plane or some such and gets awesome range... will be an interesting experiment to try tho
_________________
www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Post Fri Jun 03, 2005 10:08 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Spockie-Tech
Site Admin


Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia


 Reply with quote  

Supporting it at multiple points with stand-offs would probably work.. I assumed when you said telescopic that the telescoped-end would be hanging loose..

I like the "use a stuctural part of the bot as an antenna" idea, although there probably arent too many designs (other than a thwack-bot) where it would be feasible to electrically isolate a big enough piece of bot to perform as an antenna.. especially at 29Mhz with its long wave-length.

You might get some problems when the other bot contacts your exposed metal arm/aerial and effectively becomes "part of" your aerial. Unless you wrap the whole thing in heat-shrink..Laughing
_________________
Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Post Fri Jun 03, 2005 10:16 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
Knightrous
Site Admin


Joined: 15 Jun 2004
Posts: 8511
Location: NSW


 Reply with quote  

Biggest problem I've had with aerials is when other peoples get entangled in my weapon! You know who you are Evil or Very Mad
_________________
https://www.halfdonethings.com/

Post Sat Jun 04, 2005 8:15 pm 
 View user's profile Send private message
Totaly_Recycled
Experienced Roboteer


Joined: 15 Jun 2004
Posts: 1346


 Reply with quote  

Rubber isnt a good choice of insulator for an aerial The high carbon content can make it act as a conductor to high frequancy radiowaves.

Post Sat Jun 04, 2005 8:31 pm 
 View user's profile Send private message
Glen
Experienced Roboteer


Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect


 Reply with quote  

question, i cant open up my weapon motor and i dont know whether it has suppression coils and the like inside..

is it going to make any difference if i solder on a cap across the motor wires close after the leave the case or should i just assume it has suppression coils built in and leave it?
_________________
www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Post Wed Jun 08, 2005 6:34 pm 
 View user's profile Send private message Send e-mail Visit poster's website MSN Messenger
timmeh
Experienced Roboteer


Joined: 20 Jul 2004
Posts: 2523
Location: Victoria


 Reply with quote  

I dont think an extra cm of wire away from the brushes would make all the diff but i might be surprised when brett comes on and ses E+^)/=no it wont work Laughing
_________________
Tim Team Reaper.

Post Wed Jun 08, 2005 6:39 pm 
 View user's profile Send private message Send e-mail
Totaly_Recycled
Experienced Roboteer


Joined: 15 Jun 2004
Posts: 1346


 Reply with quote  

just put the caps on as close to the motor as posible Very Happy

Post Wed Jun 08, 2005 10:39 pm 
 View user's profile Send private message
Valen
Experienced Roboteer


Joined: 07 Jul 2004
Posts: 4436
Location: Sydney


 Reply with quote  

as a rule
more caps wont hurt

(till the legs start becoming radiators, or short to the case etc)

btw anybody got a tutotial page on modding the mini-EV's they have a case > ground connection it seems.
dosent bother us now but it will in plan-F
_________________
Mechanical engineers build weapons, civil engineers build targets

Post Thu Jun 09, 2005 1:28 am 
 View user's profile Send private message Visit poster's website AIM Address Yahoo Messenger MSN Messenger ICQ Number
  Display posts from previous:      

Forum Jump:
Jump to:  

Post new topic   Reply to topic
Page 2 of 2

Goto page Previous  1, 2

Forum Rules:
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

 

Last Thread | Next Thread  >
Powered by phpBB: © 2001 phpBB Group
millenniumFalcon Template By Vereor.