mobile-sensing

FaceListener transforms the commodity headphone into an acoustic sensing device, which captures the face skin deformations caused by fa-cial muscle movements with different facial expressions. To ensure the recognition accuracy, FaceListener leverages the knowledge distillation technique to learn the subtle correlation between face skin deformation and the acoustic signal changes.

We present a new technique to mimic an active sonar system with the smartphone’s built-in microphone and speaker, and use this sonar system to evaluate muscle fatigue from the muscle’s surface characteristics that can be measured from the transmitted acoustic signal.

We present MagHacker, a new sensing system that realizes such eavesdropping attack over commodity mobile devices, which monitor and analyze the magnetic field being produced by the stylus pen’s internal magnet. It divides the continuous magnetometer readings into small segments that represent individual letters, and then translates these readings into writing trajectories for letter recognition.

The first work that allows commodity smartphones to be used as a portable spirometer and provide accuracy lung function test results on par with clinical-grade spirometers. This is a collaborative work with the Children’s Hospital of Pittsburgh, and could also potentially contribute to in-home evaluation of COVID-19 risks by allowing convenient out-of-clinic lung function evaluation.

Device-free acoustic motion tracking allows a commodity mobile device to precisely track the human user’s motion, without applying any extra hardware tracker on the human body. We present a new system that ensures precise motion tracking over large targets by correctly interpreting the reflected acoustic signal and extracting the phase from the signal.