These days everywhere you look there is a new smart version of the devices we use in our homes. In many cases, like smart lighting and thermostats, they can be very beneficial, helping us to curb our energy use while still staying comfortable. The smart home is in many ways is a more efficient home, but it also can solve other everyday problems that come down to human error like misplacing keys, forgetting to turn off the lights and, maybe one day, burning our food.
Shahir Rahman, a 15-year-old living in Oregon, started out trying find a solution to a small problem. His dad reheated his tea in the microwave every night and, many of those nights, his tea would boil over, making a mess and burning his fingers as he tried to handle the cup. Rahman wondered, would it be possible to build a microwave that heated things until they reached the just right temperature and not a second longer?
With the help of his father, an engineer at Intel, he set out to do just that and discovered that there was a lot to learn and a lot of other problems to be solved along the way.
Shahir determined that the device he built needed to be smart enough to know what it was cooking and to get that food to a set temperature, but also cheap enough that it could be replicated and manufactured for many people to use.
“If you look at current-day heating applications, there’s different kinds—for comfort, for warming the house, for cooking—but the cooking part hasn’t become smart,” said Shahir. “This was something that I wanted to change. I wanted to improve cooking, prevent burns and create better food."
He started by dissecting a used microwave and studying how it worked and how it directed heat to different spots inside. Most microwaves have a turn table because there are hot and cold spots within the appliance. Shahir realized that he could exploit that by figuring out how to target the heat to foods that needed to get hotter than others, like heating up mashed potatoes on a plate but not the side salad.
He also thought about how the texture and viscosity of food affects the optimal temperature. Low viscosity foods like soup should be hotter while thicker foods like rice or pasta should be cooler in order to be eaten right away. Using a temperature gun to measure homemade and restaurant meals, he started creating temperature profiles for a variety of foods.
Next, he started the engineering phase. He learned Python and advanced math concepts in order to write the necessary algorithms that would identify the food and calculate how long and how hot it would need to be warmed. Then, he sought the support of his parents' co-workers at Intel who gave him the tools and mentorship needed to move the project forward.
His invention now uses an infrared Panasonic thermopile array sensor, a low-cost, low-resolution sensor that can detect the food’s temperature without touching it, and the virtual food profiles that he programmed on a microchip that can calculate the ideal temperature and cook time. Time remaining and temperature can be monitored with the user's smartphone as the food cooks. A few tweaks to the circuitry is the final step, but Shahir hopes that in the future the microwave can also detect fires before they happen and will be able to identify the food without any input from the user.
In just a couple of years we may be able to buy a smart microwave that makes heating our food more efficient and safer and it's because a 15-year-old tinkerer wanted his dad to have a perfect cup of tea.