Looking for some high torque, ~200rpm, cheap motors

Since my project is so unusual I'm not sure if you guys can help.

I either need 2 large motors to rotate my platform via belts or (preferably) many small motors turning high traction mecanum wheels.

With a 150mm wheel on each I figure 140rpm (without load) will give me 90 degrees rotation per second, so about 200rpm is close enough.

Something like these : http://www.ebay.co.uk/itm/DC-24V-0-...al_Components_Supplies_ET&hash=item43cc1e98ce

Does anyone know of an online calculator that can work out the torque need to rotate a certain mass? All that stuff is in Autodesk Inventor but I would like my doubters to be able to put in their own figures too (and check my own work)...

12v boat winch motors would do it.
http://www.ebay.com.au/itm/12V-2000...tric-Winch-Marine-Boat-4WD-ATV-/400745955422?

I'm not sure how, it says line speed is "5.5Ft/min without Load" which is 1.67m a minute... this wraps around a 30mm drum, so I only calculate less than 9rpm...

I don't need *that* much torque, this could pull about 5 spheres with people in them.... I need to rotate them quite quickly.

Indeed! We've never seen such a motion platform here before! (quite)

As you wrote, it can be calculated in detail with Inventor.
Do the cross check manually on a piece of paper. When you can convince your doubters with that piece of paper, you've done your job right.

a large chain drive on the end would increase speed and reduce torque, not sure of a calcuation that would help.
Guys here have used Boat winch motors with success, @eaorobbie , @Pit .

The noise is relatively. Let me say, my rig is a bit loud, but the winches are not as loud as the projectors are. The projectors are loud, but not as loud the PSU's are. The PSUs are loud, but not as loud the speakers are. What I want to say: all noises together give me perfect mix and are quite similar to a race car. BTW: The winches are NOT the loudest part in my rig.

Apropos winches: my winches have a max speed of 3m/s and 23 U/min. Under normal working conditions and load they need up to 40A (peak). If the max. load should be needed, the current peak could raise up to 90A................................which blows any bridge. (750W max.).

http://www.teknic.com/model-info/CPM-MCVC-3441S-RLN/

You may not even need gearbox on your application...

Can you tell us what kind of Hbridge do you actually use?
Thks

I would be glad to, here you go:

http://www.xsimulator.net/community...cts-as-a-single-motor-driver-more-power.5482/

Monster Moto dual h-bridge as a single motor driver.

Still working! Winches have been moving almost too heavy at least, so the "limit" was my body over shaking like a hell.

I forgot it was your work (I remembered your post very well... and the thrill of experimentation!)

I will probably follow your track as I wanted to play with a winch motor and I have a motomonster sleeping...
Thanks!

Uh, why has my thread turned into a discussion of slow winch motors?

"a large chain drive on the end would increase speed and reduce torque"

I need 140-200 rpm motors, these winches only give 9... they're wrong for my project by a factor of 15.... for them to work I would need a TWO meter wheel driving my sphere... correction, I would need at least three 2 Meter mecanum wheels.

if I'm missing something let me know....

Because... lol


I already gave my legitimate suggestion... This motor has USB connection where you can adjust its torque,max rpm, acceleration ramp speeds... Its not a toy motor



You may not even need gearbox on your application... as the load is constant (contact with sphere).
It has the power of AC motors, but runs only on 75volts...

$388 per servo isn't cheap, 730 rpm is far too fast for my application too and x-sim doesn't work with servos, which I would really like to use...
This might be an option for a belt drive, but it's still far too expensive.

My best option so far remains the ebay motors I outlined, I can buy 25 of those for the same price as one teknic servo and get 21Nm versus the 13Nm...
More motors will probably be better for my application since I'm unsure how much traction I can get on the sphere per motor...

No worries, you can choose what ever is best for your application. You know better how much inertia of mass power you need.

You will still need hbridges and power supply's with huge capacitors for the small ebay motors... And a controller interface to drive them with PWM... arduino maybe?

Did I mention that the clearpath servomotors work with normal PWM signals from arduino? oups.. never mind... its already too expensive for you.

A lot of the big worm gear motors may have the torque required as the mass is balanced on a bearing surface as in the cg is always supported and does move far from it centres , so inertia of the mass may not be an issue.
But until you know the amount of torque that is required for fluid motion and to hold the mass at its extremes points , you can not even consider whether it will be 240v or DC driven.

Lets get back to the real question.
So anyone got an idea on how to calculate this ?
Myself I use inventor.

Actually, if the sphere is balanced and the center of gravity in the center of the sphere the holding torque will be neglible, the motors would never lift anything or need to hold it up, just rotate the sphere....

2 motors like these do not go well?
http://www.ebay.it/itm/351066992384?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

You can put 4 rubber wheels on both sides of the shaft, and six or affixed to a chain drive rollers as you showed in your 3D to turn your sim ball

I just replied to that thread... still hoping someone can some up with european supplier...

Ok, ho visto adesso, quindi per il tuo scopo vanno bene questi motori?
Ho ricontattato il venditore e gli ho chiesto se può applicare uno sconto ... ma la vedo dura ....


Ok, I have seen right now, so for your purposes are fine these engines?
I contacted the seller and asked him if I can apply a discount ... but I see it hard ....