JRK 12v12 versus other pololu boards

[Inside]

Question!

Why does everyone use JRK 12v12s? Is it because they have the easy serial/usb interface for sending control data?

Something like http://www.pololu.com/catalog/product/760 can do 36V15 for about 60% of the cost. It seems like the only thing you'd need is a microcontroller running a PID controller to send the data. Is that the only reason why more people don't use it?

[floriske]

The JRK12V12 is a controller with feedback and driver in one unit. All you have to do is plug it in, connect psu motor and feedback potmeter, setup the software and you are ready to go.

The 36V15 is just a driver and you would still need a controller with feedback (tronic AMC for instance) to make it work. Next to that it's rated for 36V instead of 12V or 24V (the most common voltages for motors used on diy sims).

[motiondave]

Yes, and tronic and Bobbuilt and other members, are looking at other controllers as well as his to add h-bridges onto.
For the time being, there are very good 12v motors available and the JRK will run 14v at 30 amps continuous.

We would all like higher voltage option, but until a controller is PROPERLY sorted..the JRK is it.
Controller, feedback, h-bridge all set to go.

[sirnoname]

As far I can see the arduino board plus a H-Bridge is the most attractive solution.
There are two different firmware versions fom different authors that are working with X-Sim compatibility mode (USO).
The price is near the half and the H-Bridges can support more power. Also if one H Bridge is failing you can exchange them.

[floriske]

As far I can see the arduino board plus a H-Bridge is the most attractive solution.
There are two different firmware versions fom different authors that are working with X-Sim compatibility mode (USO).
The price is near the half and the H-Bridges can support more power. Also if one H Bridge is failing you can exchange them.

Prizewise it is a lot more attractive indeed, but more difficult to setup and the firmwares aren't thouroughly tested and abandoned or no longer being developed.

[tronicgr]

The cost of a burned JRK12v12 also matters...

Its easier to replace a cheap burned motor driver than almost the whole controller-driver pair. Until pololu decides to release JRK12v12 in two pieces you are limited for just 12v motors and big hole on the budget in case its burned.

Do you need even cheaper solution? You can avoid using any pololu product and go for the following:
2x Arduino Nano v3
1x High Current Dual Motor Driver Module Board with Heat Sink

You can control then 2 motors (up to 24V) for less than the price of 1 Pololu Jrk12v12. Of course you need to program the arduinos... but hey... worth a try if you are up to it.

Thanos

[Inside]

I don't mind doing the bit of extra programming or doing the feedback control myself -- I'm trying to save as much cost as possible.

Oh wow, I've never even heard of the $12 arduino. Buying one ASAP. PS: why two? Looks like each one has 6PWM outputs.

And thanks for the link for the H-bridge! That looks hella beefy. I wonder if there is a 36V version.

The reason why I was going for the 36V H-bridge is because a friend of mine is willing to give (?) me 2 36V dc motors (w/ 30lb-ft stall torque -- about 40Nm) -- http://www.mpja.com/download/14386md.pdf. I haven't really seen any cheap (<$100) motors out there that have the same torque for that price so that's why I was looking at going with these motors -- unless you've got some links for those too?

[tronicgr]

You can work the 36v motors fine on 24v... It won't slow them that much... I power my 24v motor with 12v and it still provides lots of torque.

Looking at the datasheet you provided, I see that it doesn't have permanent magnets, but electromagnets field that needs power against the armature... Cool! That could be used as 4Pole servo motor (BLDC) as well!

If you buy that h-bridge on the link, contact the seller first and tell him "Thanos from x-sim told me about it" to see if you can get a discount. I got mine for $40 (USD)


Thanos

[Inside]

Yeah, but there's like a 33% loss of torque, no? o;

[tronicgr]

The loss is not so much. For start its pretty good.

Then If you need more torque, you may change the motor driver to a 48v BLDC one and have it kick ass..