Making gadgets smarter

Most things, Waikato University electronics engineer Professor Jonathan Scott maintains, can be smarter. One of the gadgets he thinks could do with up-skilling is the common garden variety sprinkler.

“Depending on the model, you can buy one of these things for around 50 to 100 bucks. You screw it on to a tap in the garden and you just dial up how long you want it to water and how often. They’ve got a battery and will run for about a year.”

Professor Scott and engineering student Shabir Azizi have replaced the sprinkler’s original electronic board and replaced it with a new one. “And this other one is a bit smarter. It knows when the sun is up, what the temperature is, and adjusts the amount of water delivered to the plants on those variables. If you can measure light and temperature, you can make a fair estimate of how much water the plants are actually going to need.”

Shabir, as part of a Summer Scholarship project, took just over 10 weeks to produce a prototype but says the first three weeks were spent doing experiments.

“What really interested me about this project is that it involved irrigation systems and also programming micro-controllers,” he says.

Shabir works part-time at New Zealand Mushrooms, watering on the weekends. “I’ve always wanted to make an automatic watering system and when I saw this project I quickly applied for it.”

The plan now is to produce two sprinklers, says Professor Scott. “ We’ll build one that does exactly what it used to do, except it logs in its little memory how much water it has delivered. The other one will be fitted with brains, so it will change the period of time it waters, unbeknown to the user. In the last 10 years the electronic part of things has become so cheap, that you can throw in enough to put brains in there for not much more expense.”

Shabir says there were several challenges to be overcome. “First we had to make the circuit board the same size as the commercial one, so it fitted, but we needed to put a little more electronics into the same space, which wasn’t easy at all.”

Programming was the second-hardest task in the project, as it was his first time working at that level of programming. The experience has been all positive, he says.

“It’s really helped me put my study into practice, and I know that I want to keep on this path. In the future I’d like to be a PCB (printed circuit board) designer and programmer, and make some cool robots. I’ve always played around with electric toys and computers – taking them apart, putting them back together, so it’s an extension of that.”

The next step, says Professor Scott, is to produce two sprinklers and test them.

“Ideally we'll hand them over to a botanist to tell us how well they work. We hope the plants would grow equally well, but the interesting thing will be to find out how much water was used in each case. One might say it watered for 249 minutes, and hopefully the smarter one will have only watered for, say, 168 minutes.”

There are a few bugs to get out of the device, but Professor Scott says it shouldn’t take long to produce two sprinklers.

The idea isn’t new – there are smart sprinklers on the market but they are designed for farmers whose livelihood depends on producing a crop. “As a result, they are not very maintenance free. You’ve got to go out every day, and adjust the knobs.”

The sprinkler has another virtue – it would stop tanks being drained accidentally.

“It’s so easy to do, you put the sprinkler on, go off somewhere and forget about it. Then you rush out to find all the water has gone. I know,” he adds, “because I’ve done it.”