loading page

A Magnetic Field-Based Wearable Respiration Sensor for Real-Time Monitoring During Pulmonary Rehabilitation
  • +7
  • Ana Sofia Carmo ,
  • Inês Carvalho ,
  • Joana F. Pinto ,
  • Gonçalo Chambel ,
  • Ana Martins ,
  • Rute Roberto ,
  • Hugo Ferreira ,
  • Fátima Rodrigues ,
  • Ana Fred ,
  • Hugo Plácido da Silva
Ana Sofia Carmo
Instituto de Telecomunicações and Instituto Superior Técnico

Corresponding Author:[email protected]

Author Profile
Inês Carvalho
Author Profile
Joana F. Pinto
Author Profile
Gonçalo Chambel
Author Profile
Ana Martins
Author Profile
Rute Roberto
Author Profile
Hugo Ferreira
Author Profile
Fátima Rodrigues
Author Profile
Hugo Plácido da Silva
Author Profile


Objective: In the context of pulmonary rehabilitation exercise training, wearable real-time monitoring of respiratory patterns may represent a valuable tool in increasing accessibility to treatment, as well as expanding the opportunities of treatment automation and locomotor-respiratory coupling. This work explores Hall effect sensing, paired with a permanent magnet, embedded in a chest strap. Methods: Experimental evaluation was performed considering as reference the gold-standard of respiratory monitoring, an airflow transducer, and performance was compared to another wearable device with analogous usability but with a different working principle - a piezoelectric sensor, also embedded in a chest strap. A total of 16 healthy participants performed 15 different activities, representative of pulmonary rehabilitation exercises, simultaneously using the three devices. Evaluation was performed based on detection of flow reversal events, as well as fiducials detection latency. Results: The proposed sensor shows comparable performance to the piezoelectric sensor with a mean ratio, precision, and recall of 1.10, 0.89, and 0.98, respectively, against 1.35, 0.71, and 0.96 of the piezoelectric sensor, overall also presenting consistently smaller latencies. Conclusion: The characterization of the proposed sensor also shows adequate monitoring capabilities for exercises that do not rely heavily on torso mobility, but may present a limitation when it comes to activities such as torso rotations and side stretches. Significance: This work expands the applicability of Hall effect sensors, demonstrating their use in the context of real-time respiratory monitoring.