Roboclaw motor controller investigation

Moderator Edit:

This thread was split, the original thread is in the Market Place.

I found a supplier for JRK 12v12 at a much better price than on their website. Are they knockoffs? I don't know.

I'd be willing to order a demo batch and send a few out to a couple senior members to get opinions and feedback.


Let me know.

- David

Hi! Could you please share the link? I would like to check the price as I'm looking for trying 24v model if any.
Yours
Mat

I presume you are looking for the 24V12 or the 24V23?

Here is the link for the Pololu product.
http://www.pololu.com/product/1379

I will check and see if I can get that one as well.

- David

I think the Problem with the 24v12 is the amperage, 12A3 vs 30A continous from the 12v12

Its just a motor controller with no feedback, good for speed control , but no good for simulator motor control.
The 12v12 with feedback is the reason its a higher cost. It has feedback built in. This one does not.

Thanks @bsft
Yes, you have to look for "controller that can be used with feedback for closed-loop position control"

In 24V, it would be the RobotClaw serie from Pololu:
RoboClaw 2x15A Motor Controller with USB (V4) 90$
http://www.pololu.com/product/2392

• Simple bidirectional control of two brushed DC motors
• 6 V to 34 V operating supply range
• 15 A maximum continuous current
  
• Dual feedback inputs for PID closed-loop control : position control with analog encoders or potentiometers
• USB serial interface (virtual COM port)

@DigitalCrypto : I'm not sure to understand: you have found a dealer of used boards?

@RacingMat the JRK 12v12's are reported as original new unused items.

As reported above there is not a 24v version with feedback.

I will place an order for samples on tomorrow.

Might have to try one, good find @RacingMat
I emailed Pololu and asked if this might be a 12v12 alternative in 24v. I await an answer

the jrks are legendary

Thanks as I definetly want to try in 24V ;-)

This all sounds good @RacingMat ! But can you tell us how to use the RoboClaw to get position control please? And what would the code look like to control it? I’ve tried to get a grip on it but it really doesn’t make sence to me how to make this to work with motion simulators. Thanks.

I thought we have already been down this path! http://www.xsimulator.net/community/threads/pololu-roboclaw-2x60a-motor-controller-with-usb.5320/

@BlazinH : This board has many interfacing modes: maybe it's tricky , maybe it's simple...
I would be interested if we can interface it in a straigh way like JRK (as it seems it has PID inside)
I'm waiting for @bsft feedback before digging more



Yes in the other post there's a link to a library available for interfacing with Arduino
http://downloads.orionrobotics.com/downloads/datasheets/motor_controller_robo_claw_R0402.pdf

Here are other examples from Robotshop.com
http://www.robotshop.com/content/ZIP/arduino-library-and-examples-b0098.zip

@RacingMat , I have not gotten a clear answer on this yet. I emailed pololu , but they just referred me to a link on the orion website.
As my knowledge of such devices is limited, I have to say I cannot answer this question anymore.
You are welcome to email pololu yourself if need be.

This is the answer I got from Pololu

"Hello, David.

Thank you for your compliments and interest in our products. The
RoboClaw 2x15A can supply brushed DC motors with voltages up to 34V, and
it features closed loop PID control, so it seems like it might work as a
higher voltage jrk replacement. The V4 versions of the RoboClaw do have
a USB interface that lets you do position and speed control by changing
PID parameters, and it looks like you can control the motors directly
through the same interface. So, I don't think an external
microcontroller is needed to control it. However, we do not manufacture
the RoboClaw, so its interface and configuration will be different than
the jrk's. You can learn more about using the RoboClaw by reading its
user's manual, which you can find under the Resources tab of its product
page:

http://www.pololu.com/product/2392/resources

Under that same tab, you can also find a link to download the software
for configuring and controlling the RoboClaw.


By the way, it sounds like you were using the jrk as part of a
simulator. If you are currently using some simulator software to
communicate with your jrk, I recommend checking with the manufacturer,
Orion Robotics, directly to see if it will work for controlling the
RoboClaw:

http://www.orionrobotics.com/Contact-Us_ep_71-1.html

If someone else can make sense of this, please do. I am too dumb to understand these things.

That looks good!
It's worth further investigation
Thansk @bsft

I'll keep you informed

Another note they are encoder driven for feedback, pots are not supported.
They do look rather tricky to setup. Using an Ard would defeat the purpose of using them.
Goodluck.
@BlazinH these are a new version the old one could not be driven directly from USB and had some major bugs.

Interesting, many of the interface details in the manual are very similar to the sabertooth 2x60. I suspect one of the products was made to be compatible with the other at least at the interface level - can't comment on the driver itself.

Sabertooth Simple Serial matches Roboclaw Standard Serial, the packet serial modes appear the same for both, both have an RC and Analogue mode. Roboclaw has the added feature of USB though.

Not sure they are really suited to sim requirements.

Hi
For questions about the Roboclaw you can try www.basicmicro.com
They have a special place fore the Roboclaw @ there forum for jears.