We introduced the IR sensor in the last chapter, where we discussed its ability to measure the position of an infrared beacon. The Omnilander will use the IR sensor's two other functions. In addition to tracking a beacon, the IR sensor can act as a proximity sensor to measure distance (similar to the US sensor), and it can read the commands sent by the EV3 remote control. The Omnilander uses proximity sensor mode in its autonomous program and receiver mode for the RC program.