Double-post time; I just checked out the speedy-bl sie and the biggest controller is only 40 amps That's going to smoke in the first few secongs...
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

largest i found was 70 amps... i remember chris baron of sidewinder fame was making some insane brushless controller, but nothing came of it im sure theres some industrialised brushless controller out there.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

I'm pretty sure with the SpeedyBL you could combine more then one powerboard. Each powerboard is rated for 35Amp IIRC. The 70amp version runs two of these boards together, so I assume you can just solder together some more....
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https://www.halfdonethings.com/

How about this one ?

http://www.castlecreations.com/products/phoenix-125.html
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Chances are the build quality and performance would be pretty close to this one . . . http://www.castlecreations.com/products/phoenix_hv-110.html ie the one I got. I think I might just send it to them with a dirty letter and see what they say, I mean its only $90US to get it repaired compared to the $270 odd I paid for it . . .
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Jeff Ferrara
fb@ffej.net

ffej.net

i had an axial drive in mind.
make a metal disk, attach it to shaft, add rubber sheet to the face of the disk.
push rubber sheet (+ motor etc) onto simmilar doohickey on the wep drive shaft.

think of getting a spider and cutting it in half
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Mechanical engineers build weapons, civil engineers build targets

I'm bogged down in controller selection at the moment.
none of the low end MCU's do what i want to do in hardware it seems. And the only way around it is to go like a 750Mhz blackfin or something (still $4 for dual core 750Mhz cpu isnt too bad ;-> and it can run uClinux if you want ;->)

I need to look some more at the motor controll PIC's they may be able to do it, but without the flexibility i was looking for.
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Mechanical engineers build weapons, civil engineers build targets

I just did a quick low vs high tech weight comparison on the weapon drive system - it's a real shock !

OLD (as used in Jolt):

Short Mag motor...1,723g
18 Nicads.............1,620g
Relay.......................80g
total.................. 3.423g

New

1910 ORK motor....283g
6 LiMn cells...........709g
controller..............108g
total................ 1,100g

The comparison doesn't include any power transmission stuff like belts or gears, just the motor, controller and power source. Saving over 2.3Kg in a 13.6Kg bot is phenominal! If the high-tech stuff lasts as well (which I doubt) then the old "bigger gun vs thicker armour" equation has taken on a new twist. The question is whether a small motor and ESC can sustain the same power delivery as the larger and stornger old parts...
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

@ Jake: perhaps it's easiest to just hack up a mid-power comercial unit and put larger FETS on a heatsink? I was reading an R/C boating forum and the Hacker controllers with variable frequency drive and timing were well thought of. Think of the ESC as a pre-programmed ESC with driver attached
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

could work, if the drivers on the board are up to it and it wont bugger with their back EMF sensing drive thingies.

I think for robot wars we want a sensed driver, not a sensorless, because we spend most of our time starting up where the sensorless controllers dont work so good.
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Mechanical engineers build weapons, civil engineers build targets

If we got a controller with (say) 12 FETS on it, then we could replace them with 12 larger FETS having the most similar drive characteristics - sounds like it has a reasonable chance of working. Wiring up that many FETS would be a major pain without a PCB, what is the chance of making a proper board?

If modding a smaller controller is too hard, I can get a larger controller like the Jeti/Hacker 90 amp that can take more current than the battery can supply.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

The thing to remember with a proper board, a copper track on a PCB can only stand so much current. I'm building a 13.8V/20A Switchmode power regulator (yeah regulator not power supply, the controls are on the low voltage side, rather than the 240AC side) for my electronics major work, and i'm having to wire up all high current stuff off the board so i don't have arching or have tracks melt etc.

simple fix, if its surface mount just make the tracks wider and built them up with solder.

if you need any help with that knight let us know, sounds like a fun project
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

And keep them short as well as wide.

Resistance is a function of the cross-sectional area, the length and the materials resistivity.

If they're going to be long, they have to be fat, If you keep them short, they can be a lot smaller.. thats how the tiny little TO-220 legs on FETs handle 100 amp+ surges, cause they're only a few mm long. The motor wires have to be 20x the size as the fet legs, because they are much longer.

A light coating of silver-solder on the tracks will increase their current handling capacity much more than tin-lead solder as well if you really want to push it hard.
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

Thanks for all the tips! It's all theoretical for now - I still have to build the small version before getting into the bigger stuff. For people who simply have to have that giant Torcman motor, this Schulze controller might be the one to get:




Thirty large FETs, 160 amps and only 628 euros
It looks rather like what I described above; they have taken a smaller controller and added a whopper power board underneath.

@ Jake: I might need your urethane expertise to finish off the custom 3" wheels for the beetleweight - I can guarantee they will be the coolest looking beetleweight wheels on the planet .
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion