reading one of his science magazines when he got a call from a company who puts together
various interactive systems for museums around the country. They were given the
challenge by their client to design a musical chair game for small children at a museum in
a big city.
experimented with various pressure switches and strain gages to detect when a child was
sitting in the chair but they couldn’t seem to find anything that worked consistently.
Could Wily help? Wily listened to the companies requirements and thought that a
capacitance method would work. After gathering some more information he agreed to
take on the project.
The company already had the
computerized system all designed and tested. They only needed Wily’s help with the
child’s fanny detection. The sensor needed to detect when small children where seated in
small wood chairs.
The first thing Wily did was attach
some aluminum foil strips to the bottom of a hard wood chair as shown below. This
formed a two capacitor plates. The capacitance between the two metal plates on the
bottom of the chair should increase when the child was seated.