SmartMat puts the Internet of Things underfoot
By Darren Quick
March 28, 2014
We've got smart doorbells, smart locks and smart door handles, so why not a smart doormat? Dr. Andrew Clark has created just such a device called, surprisingly enough, the SmartMat. Designed to be placed under a regular doormat, the SmartMat acts as a pressure sensor and features Wi-Fi connectivity to allow actions to be triggered when someone steps on it.
Measuring 18 x 27 in (46 x 69 cm), the SmartMat is made from a pressure-sensitive plastic film sandwiched between two conductive polymer film layers, which are in turn contained within a heat-sealed weatherproof outer protective layer. These are coupled with a Wi-Fi-enabled Electric Imp micro controller that collects and processes the SmartMat data and allows the mat to connect to a home network.
Once connected to the a home network, data collected by the mat is sent to a cloud-based server that can perform actions, such as sending email or text alerts based on certain conditions. Via a web browser interface on a mobile device or computer, users are able to configure different combinations of triggers and actions.
Unlike most conventional floor sensors that function like an electrical switch – that is, either on when any pressure is applied or off in the absence of pressure – the SmartMat is able to detect the amount of pressure being applied and calculate the approximate weight of who or what is on the mat and for how long. This allows different actions to be triggered by different people, pets or objects – provided they have different weights.
Clark gives various examples of potential uses for the SmartMat, including sending a text when a pet is sitting on the mat waiting to be let in or out or a package has been left at the door, and sending a tweet whenever the mat is triggered to provide a time-stamped log of activity. The mat's Wi-Fi connectivity also allows users to set it up to control other Wi-Fi-enabled home devices, such as lightbulbs and IP webcams. With the optional Wi-Fi enabled powerstrip, the mat can also be set to turn any household electronic device running off mains power on or off.
When powered by a 9 V battery, the SmartMat should be able to remain connected to the Wi-Fi network and continuously transmit data for around three days, but a power saving mode that puts the mat to sleep after 60 seconds of not sensing any weight will extend battery life considerably – according to Clark, over 100 days when the SmartMat has weight on it for an average of 15 minutes a day.
The downside of this is that there is a delay of three to five seconds as the mat reconnects to the Wi-Fi network after being reactivated. However, the mat can also be connected to mains power via an included AC adapter for long-term or permanent placement.
The SmartMat is currently the subject of a Kickstarter campaign, with US$75 the minimum pledge required to reserve a unit. Delivery is estimated for June, 2014, if the campaign reaches the $15,000 goal.
Clark details the SmartMat in the following pitch video.