We knew that we wanted to boots to light up and make a robotic clanking sound while walking. I figured the easiest way to trigger this effect was to use a distance sensor on the underside of the boot- in this case the Sharp GP2D120XJ00F IR sensor. The sensor reads the distance from the boot to the ground and then a threshold value is set in the code so when the value exceeds the threshold the sensor tells the Arduino to turn on the light and activate the sound. Simple!
A cavity was carved out of the bottom of the boot with a Dremel tool and the sensor was mounted in place. A hole was drilled through for the sensor wires as well as the wires for the high power Luxeon LED. The wires for these were bundled together and a connector was soldered on so they could be easily disconnected from the wires that ran down through the legs of the suit. Only one sensor is needed to trigger the Arduino so the sensor was mounted in the right boot since Greg begins walking with his right foot first.