Fit-Track: Edge-Intelligent Device-Free and Battery-Free Fitness Tracking

Abstract:

Nowadays, many people have difficulty accessing dedicated exercise facilities in the gymnasium. This could be due to hectic work schedules or constant travel. In such a scenario, a person will struggle to stick to an exercise routine to keep fit. Though people have adopted electronic devices for fitness tracking, such devices usually rely on batteries and must be worn in most cases to monitor fitness activities. Hence, we proposed the design of Fit-Track, a battery-free and wearable device-free fitness tracking system with edge intelligence. Fit-Track proposes using piezoresistive (PZR) sensors to track specific exercises (such as steps, pushups, and squats). The PZR sensors are interfaced with Arduino nano33 BLE sense for data processing and wireless transmission to a mobile phone. During the design of Fit-Track, we faced challenges of power supply, interference, and computation. Those challenges were addressed through adopting a multi-modal (solar and kinetic energy harvesting) power supply, attaching a PZR sensor to each foot, and developing algorithms (both intelligent and signal processing) based on the nature of the exercise carried out for tracking counts of the activity. Experiments on Fit-Track for the various exercises (steps, push-ups, and squats) with edge intelligence showed a minimum accuracy of 99 %.

• Periodical: Applied Mechanics and Materials (Volume 935)
• Pages: 131-142
• DOI: https://doi.org/10.4028/p-11HziX
• Online since: April 2026
• Authors: Samuel Dayo Adesola*, Abdurrahman Said, Usman Saleh Toro
• Keywords: Battery-Free, Edge Intelligence, Fitness Tracking, Piezoresistive Sensor, Wearable Device-Free

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