How to Steer an Oven

So here's the plan....

I wanted to put together something simple, reliable and robust. I have looked into building my own motor drivers from plans on the internet, but that meant lots of design, ordering components, circuit layout, testing and loads of mess in the living room/Neil Lab.

Looking at commercial motor controllers for a separate robot project, I found this...

It is a Dimension Engineering  Sabertooth 2x10 regenerative dual motor driver

Here is a summary of the Specs...


Up to 18V in: 10A continuous, 15A peak per channel.
24V in: 8A continuous, 10A continuous with additional heatsinking/airflow, 15A peak per channel.


Synchronous regenerative drive
Ultra-sonic switching frequency
Thermal and overcurrent protection
Lithium protection mode 


Input modes: Analog, R/C, simplified serial, packetized serial
Input voltage: 6-24V nominal, 30V absolute max.

Looking at the product manual I came across this example of an analog input setup...

The two potentiometers in the picture are connected between the V+(5V) and Ground connections on the board and the center wiper of the pot is connected to the S1 or S2 analog input on the board.. In this configuration, when the pot is centered the input should show 2.5v and the motor on that channel is stopped. Between 0V and 2.5V is reverse and from 2.5V to 5V is forward. When I saw the picture above, I knew it could easily be converted to a Voltage Divide Photo-Bridge with two photodiodes....

So currently I have all the parts. I have been trying to come up with a mounting solution for the 'eyes' which has been giving me some problems. The eyes need to be easily adjustable do give the best sun tracking performance. My latest attempt using brass tubing was unsuccessful not to mention ugly, so in frustration, I turned to ebay for a more ready made solution...

USB LED Laptop Light

£1.75 Buy it Now price with free UK postage
We shall see if I can easily replace the LEDs with the photodiodes when they arrive...stay tuned