View Full Version : [Question(s)] Motor control

12-20-2008, 09:33 PM

I'm still new in the motor control section because I have never made a rover yet.

I was looking at the SAber tooth 2X10 amp motor driver or the 2X25 amp one that I could use on more projects for a longer period. Looks O.K. for what I want to build, plenty enough of power dilivering to the motors. I want to be able to use the motor controller from a microcontroller, or from my computer. This is what I understood until now:

1 - Computer : I will connect a 8/8/8 phigets to my computers giving me 8 digital outputs. I assume I can control the motors using serial or packetized serial (both of which I will have to learn how to do with, but I guess I can learn with your help :veryhappy: ). Can I use the SSC-32 connected to my computer to control the motors? If so, Which programs can I make, any examples, how do I connect with the serial commands?

2 - Microcontroller : I can still probably use serial, but I can also use R/C right? Not directly, but If my microcontroller is connected to the SSC-32 lets say, the SSC-32 can diliver on the microcontollers command the R/C signal to control the motors. The SSC-32 can also control other servos at the same time.

I probably need more information before making a informed choice, so if anyone can point me to infromation or help explain me how all this works with code examples, taht would be great!

Thanks to all of you,

Happy holidays!


12-20-2008, 10:14 PM
The key here is to make sure of what waveforms you want to generate: the Sabertooth you mention can do Analog, RC, or Serial data input.

Your PC probably has a serial port (maybe not if it is a laptop - but then you could get a USB->Serial such as the FTDI breakout boards that Sparkfun sells) . IMPORTANT: the serial port voltages are NOT 5V tolerant - you need a level-converter such as the MAX232 or similar to not destroy your Sabertooth.

Your micro should have at least 1 serial port, hopefully more. Your micro should also be capable of PWM which can be used to generate analog voltages. Additionally, if you configure your PWM correctly you can generate RC output. Note that if you are using something like a Basic stamp, you don't have PWM, because you don't have a real microcontroller.

The SSC32 converts serial data into RC output. EDIT: Thus, the SSC32 can be used to interface either the PC or the Micro to the sabertooth, while also giving you lots of extra servo (RC) ports. This can be important, because serial ports are always limited in number.

Phidgets 8/8/8 cannot drive motors. The digital outputs cannot generate PWM. Basically, you already have a half-dozen ways to drive your sabertooth without a phidgets though...

Thus, you have many options...


12-21-2008, 12:21 AM
I'll just add a note that I control my Sabertooth all the time with the SSC32, as well as with the Axon and Arduino, in RC (PWM) mode.