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On this robot, the team decided to try adding some LED strips to the robot.   Our idea was to use them for decoration, and possibly robot software status, and driver assistance.

===== Design =====

We used our digikey voucher for these:

https://www.digikey.com/product-detail/en/sparkfun-electronics/COM-12021/1568-1153-ND/5673739

These strips are flexible circuit boards, containing multiple LED
(Light Emitting Diode) components about an inch apart.  Each package
contains red, green, and blue LED chips.  The ends of the strip have
four terminals:

	common anode (+ terminals)
	red cathodes (-)
	green cathodes (-)
	blue cathodes (-)

To light these up, one first connects the positive side of a 12v power
supply to the common anode terminal.  Then, to light it up green,
connect the terminal for green to the - side of the 12v power.
Lighting up combinations of red, green, and blue together result in 7
different colors.

To control these from the roborio, we tried to use this chip and board:
   https://www.sparkfun.com/products/14451
   http://www.sparkfun.com/datasheets/Robotics/TB6612FNG.pdf

Although it says its meant to drive 2 motors, it drives both sides of
each motor, so it actually has *four* drive circuits that can be used
almost independently.  We used one each for red, green, and blue (and one
spare).

Connections are:
	TB6612 vcc: +5v
	TB6612 PWM : +5v
	TB6612 standby: +5v
    	TB6612 AIN1: red control input
    	TB6612 AOUT1: red LED drive output
    	TB6612 AIN2: green control input
    	TB6612 AOUT2: green LED drive output
    	TB6612 BIN1: blue control input
    	TB6612 BOUT1: blue LED drive output

We wired up the sparkfun board onto a larger piece of proto-board, and
included a scrap of the LED strip, so that we can test things without
hooking up all of the LED strips on the robot.

Control inputs come from the roborio, or another source of a 5-volt
control signal.  We wire these with the white wires of three cut-down
"PWM" cables.

+ 5 volts to run the control logic in the TB6612 comes from the red
wire of one of the PWM cables.

+12v to power the LEDs comes into the little assembly on its own
terminal strip. we wire this to a 5A breaker on the power distribution
panel (PDP).

===== Debug =====

The LED strips never worked on the robot, although the individual strips and the controller
tested fine before installation.
There were reports of smoke.

We'd like to try debugging these after the fact, to see what we might learn.