Help Creating a "Diaper Shield"

Projects General Guidance
1

Hi all. I'm a newbie and looking to build a “basic” Arduino project. I came across this page (Arduino Playground - Ideas) and got immediately excited about the “Poo and Pee detector, with a Diaper Shield, for use on newborn newbies” as I have a six month old son. But I couldn’t find any tips on what components are needed, how to start it or how it even works. Can anyone help me get started?

2

But I couldn’t find any tips on what components are needed

A moisture sensor seems like a good starting point.

3

And maybe a methane detector? Are there any other noxious gasses in pooh and fart?

4

JimboZA:
And maybe a methane detector? Are there any other noxious gasses in pooh and fart?

Must be to account for all the variation in smells, colors, and textures. 8)

And I speak as a grandfather of two still in diapers, a new one on the way, and just one out of diapers.