For those new to DIY projects that involve the use of power tools, knowing when a tool is being used in an unsafe manner is of utmost importance. For many, this can include employing the wrong drill bit for a given material, such as a concrete bit in a soft wood plank. This is why a team from the University of Ljubljana created the SafeDrill, which aims to quickly determine when misuse is occurring and notify the user.

The team’s prototype consists of a small 3D-printed enclosure that contains a Nano 33 BLE Sense while allowing a USB cable to attach for power at the front. Once attached to a cordless drill with a pair of zip ties, they captured 100 seconds of data for each of the nine different classes that include three drill bits combined with three types of materials. From here, they trained a model in the Edge Impulse Studio in order to recognize the material/bit combination.

The last part of the SafeDrill project was the mobile app. Built with the help of MIT App Inventor, the application receives data over Bluetooth® Low Energy from the Nano 33 BLE Sense and displays it to the user. For safe combinations, the text appears green whereas unsafe combinations show up in red.

To read more about SafeDrill, check out the team’s tutorial on Hackster.io.