def - the Italian musical expressive marking meaning relaxed.
- jaw tension measuring tool for singers
Rilassato is a wearable tool for measuring jaw tension during performance and practice of singers. Misplaced tension is one of the biggest factors affecting healthy sound production, endurance, and delivery potential in vocalists.
The program takes in the information from the jaw muscle sensors and visually displays degrees of tension as the singer is producing sound in real time. The user is presented with three panels, the two lower ones (red and green) intensifying in color and brightness as one tenses up (red) or relaxes (green). A larger, aesthetic, panel fades two video files based on the tension value from the sensors. In addition, a webcam allows the singer to observe themselves, as if looking in a mirror.
The program records a live session and saves it as a playable video file, where a singer could later review (examining both audio and video) when and where tension was most present in their singing.
From a technical perspective, Rilassato is a desktop application. For tension signal, the Masseter muscle was chosen for sensor placement, as it is one of the most responsive to tension in this context. Data flow is first collected in OpenViBE (a software platform dedicated to designing, testing and using brain-computer interfaces) and sent to a Max/Jitter patch that filters and scales the incoming OSC signal. There, the signal is applied to the video panels and that information is then fed to the Syphon Recorder (OS X application for recording live video from any Syphon-enabled app), which records the visual contents of the program's video, as well as built-in microphone audio, to generate the .mov file. As the tool is a prototype, steps are needing to be taken to improve on the ease of sensor placement, as currently a singer tapes the sensors to their right Masseter muscle.