Ingenious cat squirter takes the top honours

By SIMON COLLINS

A device designed to scare cats off the garden has won 12-year-old Ryan Agate first prize at an awards ceremony organised by the Royal Society of New Zealand.

The 'Scare-D-Cat' device uses a burglar alarm sensor and car windscreen-wiper pump to spray water on cats that come near it.

Ryan, from Remuera Intermediate, will receive the award alongside Auckland University Professor Peter Schwerdtfeger, who has won the Royal Society's Hector Medal, and three other eminent scientists who have won silver and bronze medals: Professor Michael Davison, Associate Professor Scott Baker and Dr Ross Beever.

Ryan's device was top in the inaugural Tectrix Technology Awards for technology students in years 7 to 10 (forms 1 to 4). Technology is a new curriculum subject that includes food technology, biotechnology, materials science and electronics.

His prize includes electronics equipment and a handheld computer organiser.

Ryan, who runs a dog-walking business from his family's Orakei home, said the idea for the device came from his grandfather's problems with cats digging up his garden.

"He really likes the garden. He comes out the next day and there is all this stuff on the footpath."

Ryan got a 12-volt passive infra-red (PIR) sensor from an electrician friend of his father, and linked it up by an electronic circuit board to the pump.

As well as squirting water at anything that passes, the electronic system turns on a light and counts the incidents.

When he made the first version, the pump stayed on too long and emptied all the water in one go. He had to get a different PIR sensor, and raised the spraying jet above the water level so that it worked only when the pump was on.

"I had water pumps everywhere. We were playing with them in the bath and got hair caught up in them," he said. He had to put filters over the pumps to keep them clear.

All these preparations still made for a fairly indiscriminate device. The infra-red sensor picked up any warm object.

"It picks up humans and dogs," Ryan said.

"I did it on my dad. That was cool."

The deputy principal of his school, Remuera Intermediate, became an unintentional victim when she took a close interest.

"I was explaining it to her, but she didn't hear me properly and went up to it. It sprayed her leg," Ryan said.

The technology teacher at his school, Mary Mason, said there were about 40 entries from 11 schools in the inaugural Tectrix competition.