Teacher Markus Opitz Saves His Voice with a Quick-Access Wearable for Common Phrases
Tired of telling your pupils to "sit down"? Let technology take the strain.
Artist, maker, and teacher Markus Opitz has grown tired, as many teachers have, of repeating himself over and over — so turned to technology for the solution, building a wearable audio player for throat-saving quick access to common phrases.
"I enjoy being a teacher. I like teaching children. But what I don't like is having to repeat certain things over and over again," Opitz explains of the inspiration behind the project. "Did you also have teachers whose sayings and phrases you kept track of? I don't want to become one of those weird teachers myself, so I make sure to vary my language. Nevertheless, some expressions do become repetitive. Can't this be automated? Yes, it can!"
Opitz' solution for the problem is a simple audio player, pre-programmed with common snippets accessible with a single button press. To make sure it's always on-hand — or, rather, on-arm — the hardware is housed in a 3D-printed chassis designed to be strapped to the user's forearm, with a series of buttons to access each sound clip for playback through an integrated speaker with potentiometer for volume control.
Inside the housing is a Seeed Studio ESP32-C3 microcontroller board connected to a DFRobot MP3 audio playback board. A simple amplifier is constructed from a BC547 transistor with a capacitor and resistor, and there's a 150mAh battery to keep all the electronics running.
"What at first glance seems like a nonsensical gadget," Opitz admits, "can be put to good use in the classroom and in sports. In addition, a connection to an external speaker could be established via Wi-Fi or Bluetooth (not included in this project)."
This isn't Optiz' first wearable project: back in October last year he showed off a compact wearable display based on Seeed's XIAO nRF52840 microcontroller board, designed to clip onto the user's existing glasses. Earlier that year he had been experimenting with a tiny camera designed to avoid "vampiric power draw" by only providing power to the hardware when the shutter button is held down.
The project is documented in full on Instructables, including source code, the 3D print files for the chassis, and a wiring diagram.