Swimming is fun, but drowning, most certainly, is not. The makers of SenTAG know this, and have developed a system that monitors swimmers' depth and motion, alerting them, with a series of alarms and LEDs, if they might be in danger. The set-up, which is designed mostly for public swimming holes, consists of radio/ultrasound transmitters (worn around swimmers' wrists) and a base station that alerts rescue personnel if someone isn't responding to the alarm. No building modification is required for installation, meaning there won't be any wires running through or around the water and operating cost is kept relatively low. The most exciting part for us, though, is that the whole rescue process is now one step closer to being completely electronic. Eventually, the SenTAG could be used to signal a Strider robot
, which could drag the victim back to land where the CPR bot
could be applied. But, don't worry lifeguards, that day is still a long way off.