New flexi force sensor integrated seat pan device with real-time biofeedback for instant poor posture alert among...

Poor posture of office workers (OWs) is needed to be self-corrected. This study aimed to develop a flexi force sensor integrated seat pan device (SPD) with real-time biofeedback for instant alerts about the poor posture of OWs and self-correction of it.

The device was constructed using a high-density polyurethane cushion, two flexi force sensors (FFS), an ESP32 microcontroller, passive electronics, and a liquid crystal display. All components are interfaced with custom-written Arduino software and linked to smartphones via the Blynk application. The SPD was tested with the gold standard Universal Testing Machine (UTM) for its linearity, repeatability, and test-retest reliability of load detection. The SPD was tested among three physiotherapists using simulated poor posture and proper seated posture (PSP) and further tested among 14 OWs whose body weight ranged from 40 to 90 kg.

With a linear regression of r = 0.99 for both FFS sensors, the voltage output of SPD rises steadily and linearly against the imposed compressive load, which spans from 0 to 90 kg. The upper and lower 95% limit of agreement for the SPD's voltage difference with the real mean of FFS 1 and FFS 2 were (4.72 mV and - 4.78 mV) and (4.32 mV and - 6.96 mV), respectively. With an ICC of 0.99, SPD's test-retest reliability revealed excellent reliability. SPD performance testing among 14 OWs found that it delivers an immediate alert whenever they adopt poor posture and aids in self-correction.

SPD alerts poor posture instantly among OWs.