Step 3c : Construct the Controller
Notes and Modifications:
Skip the parts about testing the controller board. Just plug in your battery into the Roboduino. Plugging in the servos are extremely easy. Just plug in the servo header into Pin 5 and 6, the ones marked PWM. Plug the servo header in with the yellow part of the header facing towards the center of the board.
Also if you haven't yet done this(you were instructed to do this in Step 1 of the tutorial, follow the part that details choosing the proper resistor value for the photoresistor. Then just plug in the photoresistors analog pins to Analog Pin 0 and Pin 1.
Here is that part, I copied and pasted it here for your convenience
Now you must make two photoresistor sensors. Go to the photoresistor tutorial and
follow the detailed instructions. I used a 1.5kohm resistor for R with the middle
sized photoresistors in the RadioShack kit, but your situation might be different so you might
want to recalculate your R value.
professional method and makes your sensor more modular (can be scrapped for future robots).
The disadvantage to it is that the crimping tool can be a little expensive.
You dont need to do the crimping method described to make this sensor, but its a better method.