Let's Make Robots!

Mr Basic - drive train too stiff for motors to move...

I just picked up a Mr Basic kit from one of those free shipping Chinese stores. It's gone together OK, but the drive train is really stiff and the motors can't move it (even on 6xAA NiMH). Any tips?

Opinions on this cheap stepper option?

As well as working on my Arduino based "start here" robot with cheap geared DC motors, I've been planning out where I want to go next, and have been reading up on stepper motors. This seems like a cheap option for experimentation:

http://www.futurlec.com.au/Mini_SMCC.jsp

An informative controller card with a detachable, small, 7.5 degree stepper for just over ten dollars. A couple of these might make a more robust motor system for my starter 'bot. Anybody used these?

Another TI coupon offer

On the general principle of "you can't have too many toys":

http://e2e.ti.com/support/microcontrollers/tms320c2000_32-bit_real-time_mcus/f/173/p/87857/303727.aspx

Basically, $11 USD for a F28069 Piccolo controlSTICK. Normally $40. Be quick if you want one!

Providing 5v to Arduino and 3v to motors : battery and circuit options?

I have a couple of Dagu geared motors, which have this as a basic spec:

Suggested voltage: 3V DC
No Load Current: 125mA (max.170mA)

I want to control them from an Arduino. Can anyone provide some basic options for doing this? I have some parts that might help me assemble a circuit to do this, specifically: