Skip to main content

DIY backyard security system turns on the sprinklers when it sees a trespassing cat

el gato android ransomware cat
Flickr/Jarjav CC
What’s the best way to stop cats from pooping in your garden? Depending on who you ask, answers might include ultrasonic cat repellents, chicken wire, or the use of certain plants to protect your lawn from feline defecation.

For Nvidia Systems Software Engineer Robert Bond, however, there was only ever one possible solution: training a deep learning neural network to turn on his garden sprinklers whenever it recognized a cat in his front yard.

Recommended Videos

“I mounted a camera on the garage that looks out over the garden,” Bond tells Digital Trends. “The camera is set to send images to an [Nvidia Jetson TX1] whenever something changes. The [TX1] then uses deep learning to decide whether the thing that moved is a cat or something else. If it’s a cat then it activates the sprinkler system.”

catsprinkler1
Image used with permission by copyright holder

Bond says that he started training his neural network with a data set of around 1.2 million pictures gathered from the internet. These included plenty of pictures of cats, but most of them turned out to be cutesy close-ups portraits, rather than the kind of pictures he was looking for. “It was almost worthless for what I needed to do, because I was hunting for pictures of cats slinking around in my bushes,” he explains.

Please enable Javascript to view this content

Bond notes that at this point his neural network was only successfully classifying around 30 percent of the cats that came into his garden. He decided to modify the neural network’s training examples by adding pictures he had taken himself. Recognition scores immediately jumped to around 90 percent.

catsprinkler2
Image used with permission by copyright holder

The system hasn’t been perfect, however. For one thing, during the training process shadows were regularly classified as cats because they represented dark shapes moving across Bond’s lawn. Even Bond wasn’t immune from being classified as a feline. “I went to mow my lawn and the system somehow decided that the combination of me and my lawnmower counted as a cat,” he says. “I wound up getting pretty thoroughly sprayed.”

But for the most part the deep learning network has been a resounding success — and Robert Bond’s garden is now virtually cat free.

It’s simple when you know how, right?

Luke Dormehl
Former Digital Trends Contributor
I'm a UK-based tech writer covering Cool Tech at Digital Trends. I've also written for Fast Company, Wired, the Guardian…
Hyundai Ioniq 5 sets world record for greatest altitude change
hyundai ioniq 5 world record altitude change mk02 detail kv

When the Guinness World Records (GWR) book was launched in 1955, the idea was to compile facts and figures that could finally settle often endless arguments in the U.K.’s many pubs.

It quickly evolved into a yearly compilation of world records, big and small, including last year's largest grilled cheese sandwich in the world.

Read more
Global EV sales expected to rise 30% in 2025, S&P Global says
ev sales up 30 percent 2025 byd sealion 7 1stbanner l

While trade wars, tariffs, and wavering subsidies are very much in the cards for the auto industry in 2025, global sales of electric vehicles (EVs) are still expected to rise substantially next year, according to S&P Global Mobility.

"2025 is shaping up to be ultra-challenging for the auto industry, as key regional demand factors limit demand potential and the new U.S. administration adds fresh uncertainty from day one," says Colin Couchman, executive director of global light vehicle forecasting for S&P Global Mobility.

Read more
Faraday Future could unveil lowest-priced EV yet at CES 2025
Faraday Future FF 91

Given existing tariffs and what’s in store from the Trump administration, you’d be forgiven for thinking the global race toward lower electric vehicle (EV) prices will not reach U.S. shores in 2025.

After all, Chinese manufacturers, who sell the least expensive EVs globally, have shelved plans to enter the U.S. market after 100% tariffs were imposed on China-made EVs in September.

Read more