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Pololu dual motor controller + Tamiya 70168

I bought a Tamiya 70168 twin gearbox and Tamiya wheels and hooked them up to my Pololu micro dual serial motor controller.  They don't even budge.  I hooked up GM-10 motors and they work as they should.  I changed motor power to 9v instead of 6v, motor 0 turned for a second and stopped.  Again the GM-10 motors ran fine.  If I apply power direct to Tamiya from battery, either 6v (4 @ AA) or 9v (9v cell), it turns as you would expect.  All of this was done with no load on Tamiya, the wheels were not even touching the ground.  I used freshly charged batteries.

 Any ideas?  I'm stumped.  Would a 0.1 uF capacitor across the motor leads help?

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Hy,

I find the solutions very interesting about controlling servos with pololu. I found many stuff about this in the pololu forum but am not able to register there. So i've tried to search for different forums to talk about pololu.

Does anybody here know how to connect the pololu uSSC to the arduino USB Port to get the Code of Nate (krazemonkey at pololuforum) to work?

 Are there some initialisation-routines missing in the code Nate posted? I think I am only too stupid to get it work. The LED already blinks ....

LINK to Pololu Forum - concernig Problem

Thanks a lot

Andy

In general, the more capacitors you have, the better the noise suppression.  The Tamiya motors are quite noisy electrically, so just one cap across the leads might not be sufficient depending on the sensitivity of your electronics and how isolated their power supply is from your motors.  For the greatest noise suppression, you can solder one cap across the leads and one cap from each lead to the case (for a total of three capacitors).

Dealing with motor noise

- Ben

Thanks Ben!

Another option when using the Tamiya gearboxes is to replace their FA-130 motors with replacement Solarbotics motors (RM3), which operate at higher voltages, draw much less current, and are much less noisy electrically.  The RM3s are the same size as the FA-130s, so it's easy to swap one for the other, and the RM3's can be driven by the Pololu micro dual serial motor controller.

http://www.pololu.com/catalog/product/604

 

- Ben

http://www.pololu.com

 

Hey, that's a great tip. I'll stick a few in my cart to include in my next order, thanks.

Dan

And they say you can run the RM3 with the Micro Dual Serial Motor Controller.

"The RM3 motors are not as electrically noisy and draw much less current than the FA-130 motors used in many of the Tamiya gearboxes. The two motors are the same size, so if you would like to use our Micro Dual Serial Motor Controller, Orangutan Robot Controller, or Baby Orangutan Robot Controller with the Tamiya gearboxes, you can simply replace the original Tamiya motors with the RM3 and you’ll be set! (Tamiya gearboxes that work with the RM3 include the popular 70168 Double Gearbox and 70097 Twin-Motor Gearbox.)"

 

Of course, I saw that after I spent $32 on a low voltage motor controller.  I could have had 8 replacement sets of motors for that amount.  :(

my tamiya dual gearbox cannot even manage to move my bot with 3 AA @ 1.2V each. i have to use at least 4 (and btw my bot is light too)

Hmm. What gear ratio did you assemble it with? I used C for mine, and it does just fine, and my bot isn't the lightest :) If you used A or B, I could see it having trouble -- I haven't tried those, but Frits says they're too weak.

Dan

C ratio for mine too... i don't get why... are you using 1.2v (that's rechargeable) batteries like i am?

What are you using as your motor driver?  Some drivers have large drops between the input voltage and output voltage.  For example, the L298 can have a maximum total drop of 3.2 V at 1 A.  Have you checked to see what your driver's output voltage is when you drive your motors with three cells?

 - Ben