Rich will be wearing an Actiwatch, a wristwatch-like device that is a recording accelerometer. When Rich is moving, it records that movement on a computer chip built into the watch. When Rich is asleep, and his wrist stops moving, the chip records that also. Periodically, Rich will download the data to the onboard laptop, then emailed via satellite to Dr. Newman for analysis.
When Rich goes below for a nap, he scans the horizon for other vessels. At the average speed of Great American IV, if another ship came over the horizon just as Rich went below, they might converge in about 20 minutes. Thus if Rich aims for a 40 minute nap, the first half is safe, the second half is at risk. A helpful technology is the Active Echo Radar Transponder (AERT) that Rich has aboard the boat. The AERT will beep an alarm if the unit receives another vessel’s radar signal, and Rich will wake up and be able to take evasive action. The AERT unit helps again by sending a radar signal back to the other ship that will make Great American IV look like a big ship, so she will be noticed.
The idea behind the 40 minute nap is that it can work in sync with the natural sleep cycle. If Rich wakes up after 40 minutes he can go up on deck, look around to make sure that all is OK on deck, and then go back to sleep. By sleeping in 40-minute segments, Rich may be able to resume where he was in his sleep cycle, without having to start the cycle all over again. Thus, he can optimize the effect of his naps. The technique is called “cluster-napping”. Rich will be practicing cluster napping on this voyage.