The light module is basically the Simple Bots light sensor in a rugged directional casing with two convenient wires protruding. By adjusting the size of the iris (clear opening), you are able to make the module as responsive to ambient light as you would like. By splicing this in series with your motor circuit you can make your bot light-responsive.
Step 1: Go Get Stuff
You will need:
- 1" clear paint cup
- Simple light switch
- Any standard NPN transistor (for example, a 2N2222)
- 1" shrink tube
- 22 awg solid core wire
Step 2: Cover
Drill a 1/8" hole in the cover of the paint cup.
Remove the cover, pass the wire through, and tie a knot to prevent is from being pulled back through.
Step 3: Attach the Light Sensor
Attach the light sensor to the wire on the underside of the lid.
When you solder the wire, try to connect both the light sensor and knot as closely together as possible.
The longer leg from the light sensor should get soldered to the red wire.
The shorter leg should get soldered to the short wire.
Once soldered, trim away any excess wire and component leads.
Step 4: Glue
Position the light sensor on the underside of the lid such that the photo transistor is pointing perpendicularly outwards.
Glue it in place with a hot glue gun. Be careful not to get any hot glue on your fingers.
Step 5: Cover
Slide the shrink tube over the body of the paint cup and trim it so that there is no excess slack sticking off the end.
Quickly shrink it firmly into place with a heat gun.
Step 6: Case Closed
Place the lid back onto the cup to complete the module.