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IBC controlling 2-3 Magnum 550's per channel.


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dcrobotics



Joined: 06 Oct 2010
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IBC controlling 2-3 Magnum 550's per channel.

Can the IBC ESC handle 2-3 magnum 550 motors (like those sold at Motion Dynamics) per channel? If not IFI Victors be the way to go. This is for a featherweight robot.

Post Sun Sep 25, 2011 3:01 am 
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bytraper



Joined: 31 Oct 2005
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No... the motors are too current hungry. If they stalled you'd have a fried controller.

Post Sun Sep 25, 2011 7:48 am 
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seanet1310



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2-3 550 size motors per side. This robot is going to have a fair bit of weight in the drive train.

And no the IBC is not suitable for 2-3 550's per side. You may get away with two 550's per side if you add cooling and heatsinks however I WOULD NOT RECOMMEND IT. IBC in rare occasions die when single 550's or similar enter full stall.

If you plan to push a ESC very hard (running 3 motors off one side) then Victors are the way to go and have been proven to handle everything well. Just do the cable tie mod (see wiki) and maybe look at nicks epoxy mod although I do not know of anyone else needing it.
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Post Sun Sep 25, 2011 9:15 am 
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dcrobotics



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Thanks for the advice. This forum is very helpful. I figured 3 of the Magnum 550's per side might be overkill. I thought it would be faster and easier than a belt or chain set up. But fast and easy always ends up failing, so do you think just 1 550 magnum per side at 14.4 volts or maybe 18 volts will be enough speed for a featherweight ram/lifter with 4 and 1/2 inch wheels? The other drives I was considering was a pair of Powerdrive DeWalts? Are they better than the 550 Magnums or overkill again? Sorry for so many questions, but you guys really know your stuff and since this is my first robot, I figured I ask first before committing to anything . Calculators and online drive simulators are cool, but you guys have real world combat experience, so I would like your opinions.

Post Sun Sep 25, 2011 12:06 pm 
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marto
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I am not even sure you can buy an IBC anymore....

Victors are proven but expensive and large.

Don has used the TZ85as in a 4WD bot and he was still driving around despite one jammed gearbox and ESCs did't fail.

You could easily run 3x550s off any of these without load however this completely changes when you are pushing heavy loads, your gearbox jams or your motor fries. In these cases the current handling of the ESC becomes important.

Steve
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Post Sun Sep 25, 2011 2:10 pm 
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Spockie-Tech
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AFAIK Jason still wholesales IBC's to the Robot Market Place, so you can probably get them through there.. Im not certain though, I have only chatted with him briefly in the last few months and havent asked.

We never setup an easy to use Australian Retail Outlet/Website because the volume of sales in Australia was (and probably still is) Tiny comapared with overseas.

20 Million people in Oz, a fairly small percentage of builders since we never had mainstream TV coverage. 300 million people in the US alone, along with all their international customers and a fairly strong following with the mainstream media/sponsorship etc.. It was just never worth it.

I think he sold about 1 Australia Controller for every 50 or more overseas, which is why they are/were harder to get here than overseas. You had to email him or me, arrange postage/payment etc..

The lack of current limiting is probably its biggest lack these days, you need to be an intelligent user to get the most out of them without blowing them up..

I think Gary and I put hundreds of fights on them without a single failure, but it seemed people with dodgy wiring, crap batteries, no connectors, or little electrical knowledge were always blowing them up and obviously needed a more "user-friendly (or should that be idiot proof ? Wink type of controller rather than the "simple and powerful but needs skill to use properly" design philosophy.

I dont think theres *still* anything comparable in terms of open-source, repairable, integrated (2drive+weapon+mixer), comapact and reasonably powerful.. but they are a 10 year old design now.. Smile
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Post Sun Sep 25, 2011 3:11 pm 
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dcrobotics



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Thanks to all of you for your help.

Post Mon Sep 26, 2011 1:15 pm 
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Glen
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MMMM well experience dictates it would probably be on a knife edge, every 4 motor featherweight in this country with an IBC has blown it so far (singularity, all the different KO's, other tims first wedge), the only one i can recall that has worked was the very first KO that had really low traction wheels as a kind of artificial current limit. That many motors is beyond its capacity if you want to make a bulletproof robot.

I cant recommend the Robot power sidewinder either. When it works, it works fantastic and the control is really amazing. BUT i've had two blow up. One was a manufacturing fault where a screw holding the heatsink temp sensor fell out and shorted the board and the other was an unexplained explosion basically. Kinda left with bitter feelings towards that controller considering its phenomenal cost (>$500), the UK guys have had a history of problems with them too.

IFI 883-885s though, not the smoothest control, the casings are weak as anything and they provide no other features aside from driving the motor, but seriously they are THE most reliable controller to date and i too would have no probs recommending them for what you want to do Smile

Steves big brushless converted ESCs might be worth a look too. Not particularly battle tested so far but they are much cheaper then anything else and early results look pretty promising. You could probably use one controller per motor and still save some money over a brand name controller.

And the drives themselves, i'm looking at some magnums at the moment, they look pretty good and with the cost of drills going back up for whatever reason maybe not such a bad choice. Dewalts however will crap all over them and any other feather drive.

BUT everything is a compromise. They are heavy and physically large (1kg + per side vs 500g for a drill), they draw a TON of current. 2.2ah of battery capacity will just get you by for a fight and they need a beefy controller. But that being said they are super reliable. Cobra went FIVE YEARS on the same set of drives. i ended up replacing the brushes and bearings because they wore out from use. I cant recall that ever happening in any other robot ever Laughing

If you can afford them and you dont plan on having a weapon, then dewalts too get my thumbs up Smile

Anyway theres some thoughts for you to digest lol, best of luck Smile
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Post Mon Sep 26, 2011 1:41 pm 
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Spockie-Tech
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quote:
Originally posted by Glen:
every 4 motor featherweight in this country with an IBC has blown it so far (singularity, all the different KO's, other tims first wedge), the only one i can recall that has worked was the very first KO that had really low traction wheels as a kind of artificial current limit.


The Stainless Steel Rat ran for years with a 4WD Drill Setup on an IBC without a problem..

It did have limited-traction Red Wheels and Gary added external heatsinking and a small CPU Fan to help cool it though. So, it can be done, but it is pushing it to the edge Smile
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Post Mon Sep 26, 2011 9:58 pm 
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dcrobotics



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Glen do you mean I should run four ESCheap85 if I run 4 motors (Either Dewalts or Magnum 550s)?

Post Tue Sep 27, 2011 2:54 am 
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