IoT-Based Wireless System for Gait Kinetics Monitoring in Multi-Device Therapeutic Interventions

Abstract

This study presents an IoT-based gait analysis system employing insole pressure sensors to assess gait kinetics. The system integrates piezoresistive sensors within a left foot insole, with data acquisition managed using an ESP32 board that communicates via Wi-Fi through an MQTT IoT framework. In this initial protocol study, we conducted a comparative analysis using the Zeno system, supported by PKMAS as the gold standard, to explore the correlation and agreement of data obtained from the insole system. Four volunteers (two males and two females, aged 24-28, without gait disorders) participated by walking along a 10 m Zeno system path, equipped with pressure sensors, while wearing the insole system. Vertical ground reaction force (vGRF) data were collected over four gait cycles. The preliminary results indicated a strong positive correlation (r = 0.87) between the insole and the reference system measurements. A Bland-Altman analysis further demonstrated a mean difference of approximately (0.011) between the two systems, suggesting a minimal yet significant bias. These findings suggest that piezoresistive sensors may offer a promising and cost-effective solution for gait disorder assessment and monitoring. However, operational factors such as high temperatures and sensor placement within the footwear can introduce noise or unwanted signal activation. The communication framework proved functional and reliable during this protocol, with plans for future expansion to multi-device applications. It is important to note that additional validation studies with larger sample sizes are required to confirm the system's reliability and robustness for clinical and research applications.

Keywords: Internet of Things; MQTT protocol; biomechanical sensors; gait analysis; smart insoles.

Figure 1

General components of the system. (a) Insole film sensor, (b) EVA lining, (c) prototype in use, (d) 8-wire Ethernet RJ-45 to FPC adapter, (e) electric diagram. Source: Authors.

Figure 2

Proposed communication structure. Source: authors.

Figure 3

Diagram for MQTT data request. Source: authors.

Figure 4

Representation of device configuration screens. (a) Set booting mode, (b) access point, (c) screen device configuration. Source: authors.

Figure 5

Experimental setup abstract. Source: authors.

Figure 6

Pearson’s correlation plots between the insole and Zeno systems. Source: authors.

Figure 7

Bland–Altman plots. Source: authors.

Figure 8

Mean and standard deviation of vertical ground reaction forces during four gait cycles with all volunteers (ID 1, ID 2, ID 3, ID 4), comparing the Insole and Zeno systems. Source: Authors.