karaloop P2.0
The karaloop P2.0 uses potentiometers and switches to capture voluntary movements of the face.
Unlike the karaloop P1.0, the karaloop P2.0 integrates headset and control box in a single wearable unit.
The karaloop P2.0 incorporates a headset band that houses a rechargeable built-in battery and the Bluefruit nRF52 Feather board which is automatically recognized via BLE as a human-interface device (HID) by any PC, iOS or Android device. The headset further integrates three mechanical contact probes that detect voluntary movements of the face: a switch-based probe that captures forehead movements, and two potentiometric probes that capture orofacial movements bilaterally. Several headset probe holders allow the adjustment of the mechanical contact probes to fit different face contours. Its modular design further facilitates the easy replacement of probes and the rapid testing of new probe designs.
The karaloop P2.0 is the less mature prototype in this repository (TRL 3) and requires substantive firmware, hardware design and evaluation work.
By using the Bluefruit nRF52 Feather board, the karaloop P2.0 is Arduino compatible. But this requires first installing the Adafruit Bluefruit nRF52 BSP (Board Support Package) and test it. Check Adafruit's Arduino Support Setup for details. Once installed, it is possible to flash sketches using the Arduino IDE.
The karaloop P2.0 firmware sketch reads the signals from the switch and potentiometric probes and translate them into HID mouse commands which are sent via BLE to any device. The sketch is available for download here.
Electronic and mechanical design source files are available for download here.
The karaloop P2.0 assembly guide is available for download here.
This wiki documentation work is licensed under a Creative Commons Attribution 4.0 International License.
