need help

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haz
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need help

Post by haz »

hi im new to antweights and have bought some servos and a radiolink 2.4ghz transmiter and i wondering what should i do so i don't break anything because im poor and i cant afford much :D
razerdave
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Post by razerdave »

Hey Haz

First off, welcome to the forum :)

Second, what servos did you get ? Modifying servos for 360 degree movement should be simple in all servos but its helpful to know which ones you're using.
haz
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Post by haz »

i got 3 sd200 servos are they any good
alasdair
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Post by alasdair »

I used to use SD200s on DisobidiANT. COMPLETE NIGHTMARE! Firstly, the new kind of SD200s dont have a guide on the internet. We had to work out how to do it ourselves. Then, they kept blowin up! I think there are 5 blown SD200s and one working in my bitz box at the mo. Go for gearmotors i say! :wink:
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Team Orr
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Post by Team Orr »

never had a problem with them myself....
"if it wasn't for Edison we'd be watching TV by candlelight"
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bitternboy
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Post by bitternboy »

Me neither, I think saying they blow up, and constantly at that is exaggerating. I've been using a pair since the beginning of my antweight hobby and I've never had a problem. Just out of interest, what voltage were you using them on Alasdair- that may explain them failing. To haz, all I can say is to stick with them and run them on 6v since they sacrifice a fair amount of speed for torque and are a bit of a pain at 4.8v. Hope this helps. :D
Jonathan Atkinson
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BeligerAnt
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Post by BeligerAnt »

Hi Haz and welcome!

The idea behind modifying servos for 360 degree rotation is the same, even if the exact method varies between servos and people.

The 3 things you need to do are:
1. Remove any mechanical stop that prevents the final gear of the servo from rotating 360 degrees. This may be on the gear or the case.
2. Disconnect the output gear from the feedback potentiometer ("pot'"). Sometimes this involves drilling out the gear, or some other method.
3. Fix the feedback pot' at its mid-point. This can be done by gluing the pot' or replacing it with 2 fixed resistors, depending on how handy you are with a soldering iron.

There are various mod guides around. If you can't find one that exactly decribes your servo, you should be able to piece together what you need to do from bits of each guide and some common sense. If you get really stuck, ask here - pictures help!

Before you start, connect the servos up to the receiver and battery, and check that the servos operate correctly. There's nothing worse than trying to modify a broken servo!

Use large wheels. Servos are not very fast, so bigger wheels will stop your 'bot from being too snail-like. Aim for 70mm+ diameter.

Hope this helps. Take it slowly and carefully, check everything, and you should be OK.
Good luck!
Gary, Team BeligerAnt
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Team Orr
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Post by Team Orr »

bitternboy wrote:Me neither, I think saying they blow up, and constantly at that is exaggerating. I've been using a pair since the beginning of my antweight hobby and I've never had a problem. Just out of interest, what voltage were you using them on Alasdair- that may explain them failing.
+1

@ haz: iv been running a pair of sd200's in valliant since the begining, an iv never had them fail yet (well...unless you count the time my dad sat on it...and i dont :p) so stick with them, get a robot together and come to some events, once your there you will pick it up pretty quick :)
"if it wasn't for Edison we'd be watching TV by candlelight"
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bobblebot
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Post by bobblebot »

SD200s have been running in Bobblebot for the last 7 years, no problems with reliability here.
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peterwaller
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Post by peterwaller »

Welcome to the board Haz. As you can see by the number of replies new people are always welcome into antweights. The only advice I would add is to try and get to one of the less formal events first where you can talk to the other roboteers and check out the other robots. You don't give any indication where you are from but next month there are events at Aylesbury 9th May and Reading 26th May. Even if you don't have a working robot yet you would gain a lot of information and I am sure someone will let you have a drive.
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