Moisture Sensor Wireless Moisture Sensor for G-Tube Feedings, by Zachary Zillmann Mentor: Bill Zillmann My science fair project this year was to develop a wireless moisture detector using simple electronics, modular electrical components, and programmable microcontrollers. The detector would alarm if baby formula was detected from a leaking G-tube during a feeding. I wanted to make this device in response to my sister who was on a feeding tube when she was a baby. The problem is the feeding tube can disconnect during night feedings and feed the crib instead of the baby. I wanted to come up with something that would notify the parents if this occurred. My research has shown that that there is no such device available. I went through the Stamps In Class™ "What Is A MicroController" during the summer and soon realized the detector would be a great project to do with BASIC Stamp® module and the Board of Education® carrier board. All I had to do was add a few of the Parallax modules. I etched a simple circuit board with a zig-zag pattern for the sensor that shorts when it's wet. A voltage divider was used to input the signal into the microcontroller (BASIC Stamp module): 0 volts for the "dry" state and 1.5 volts for the "wet" state. Through the testing of various resistor values within the voltage divider I was able to set the sensor sensitivity. Then I programmed the microcontroller (Basic Stamp module) using PBASIC software to monitor the sensor input, alarm, and transmit a signal when the sensor got wet. I programmed a second Stamp to receive the signal, alarm, and display a text message. RF Modules from Parallax were used to provide a wireless communication. The text message was displayed on a 2X16 serial LCD also from Parallax. I won 1st place in Junior Engineering at the Denver Regional Science and Engineering Fair. Which earned me $20 dollars and I was nominated to participate in the Discovery Channels Young Scientist Challenge. I then went on to the state competition were I won A special award from the Rocky Mountain Inventors and Entrepreneurs that came $50 dollars and a 1 year membership to their organization. I also won 2nd place in the Junior Engineering division which came with $75, a medal, and a certificate.