If you have spent any time in front of a television, late at night, at any point in the last few decades of the 20th century, you can very likely sing the jingle for The Clapper, a sound-activated electrical switch. Maybe you even had one. Or maybe you have one still. It turns out that The Clapper—used to control the electrical power to any device plugged into it when it detects a user clapping—is still on the market. In fact, it’s currently ranked number four among Amazon’s best-selling home-automation devices.
However, The Clapper recently got a new competitor: the Knocki. Instead of responding to sounds, the Knocki uses an accelerometer to detect vibrations, transmitted via a person knocking on a wall or countertop near the device. A single knock awakens the unit, which then listens for one of several preset patterns that the user sets up via the Knocki app for iOS and Android smartphones and tablets, or at the Knocki website. An algorithm running on the device’s microcontroller interprets the knocking pattern before triggering the command to which it was matched when the user initiated the device. “Vibrations that are irregular won’t trigger Knocki to do anything,” says Jake Boshernitzan, a co-founder of Texas-based Swan Solutions, Knocki’s creator. “So you don’t have to worry about a heavy truck hitting a pot hole in the street or kids banging on the kitchen table.”

A user who tends to misplace her mobile phone inside the house, for instance, might set up a Knocki unit to trigger an audio alarm on her phone whenever she knocks once to awaken the device and then three times, quickly, on the wall or countertop. The Knocki can reliably detect a knock within 6 feet through wood or drywall, Boshernitzan says, but denser materials, such as granite or marble, have a shorter range. Or perhaps a consummate bachelor would establish a signal—one knock, pause, three more—to trigger his smartphone to order a pizza via a restaurant app. The algorithm ensures that random vibrations, such as a passing heavy truck or a slamming door, will not trigger the Knocki, Boshernitzan explains.
Knocki comes with a few pre-set functions, and users can employ application programming interfaces (APIs) through the Knocki website or mobile app to enable the device to control some smart-home products made by Wemo, Insteon and Philips Hue. According to Boshernitzan, Knocki users will also be able to set up custom functions by using If This Then That software.
The device runs on AA batteries, with an expected year of life under regular use. It communicates via a Wi-Fi connection, meaning that a user need not rely on a smartphone to set up or program a Knocki. Instead, a Knocki owner can do this via the Web browser running on his laptop or tablet PC.
Knocki also offers a mobile phone app that can be used to connect with and program the device. The mobile app employs Wi-Fi to connect to the Knocki unit and a cellular network connection to set or change functions or link to APIs on the server. The app is also required to perform functions specific to a mobile device, such as making a smartphone sound an alarm if its user knocks in a set pattern associated with finding a misplaced phone.
The $59 Knocki, which is now available for pre-order (with expected delivery in the first quarter of next year), is a long way from the smart-home product that Boshernitzan and his partner, Ohad Nezer, set out to make three years ago. When they founded Swan Solutions, their sights were set on creating a sort of Fitbit for the bed, but with added functionality.
By integrating sensors directly into bedding textiles, they envisioned a system that would be able to track a user’s movements and sleep patterns, and then upload them to some sort of app that would allow her to track the quantity and quality of her sleeping hours. In addition, they foresaw a means of turning those textiles into a user interface, with which the slumbering party could utilize hand gestures to “write” commands on the sheets. So a potential application would be as follows: Wake up and swipe your hand in a set pattern across the bed sheets, and the connected coffee maker in the kitchen starts brewing.
Swan Solutions has filed a patent that describes how such a system would work, as well as another describing the Knocki system. The pair decided to move forward with the Knocki concept after conducting a focus group. “The response was phenomenal,” Boshernitzan reports. Then, he says, after looking into The Clapper and learning that it’s still a viable product, the pair were shocked. “It gave us a good hunch that we’d do well with the Knocki.”
“We think we’ll still do the textile application, down the road,” Boshernitzan says. “We have some IP [intellectual property], and we might be licensing the technology in the medical space as a way for patients in nursing homes to call for a staff person.” The concept would use a capacitive sensor pad integrated into the bed. “It would replace call buttons that are now used,” he explains, “but which tend to fall off the bed.”