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A new smart insole system that monitors how people walk in real time could help users improve posture and provide early warnings for conditions from plantar fasciitis to Parkinson’s disease. Constructed using 22 small pressure sensors, and fueled by small solar panels on the tops of shoes, the system offers real-time health tracking based on how a person walks, a biomechanical process that is as unique as a human fingerprint.
This complex personal health data can then be transmitted via Bluetooth to a smartphone for quick and detailed analysis, says Jinghua Li, co-author of the study and an assistant professor of materials science and engineering at The Ohio State University.
“Our bodies carry lots of useful information that we’re not even aware of,” Li says. “These statuses also change over time, so it’s our goal to use electronics to extract and decode those signals to encourage better self-health care checks.”
It’s estimated that at least seven percent of Americans suffer from ambulatory difficulties, activities that include walking, running or climbing stairs. While efforts to manufacture a wearable insole-based pressure system have risen in popularity in recent years, many previous prototypes were met with low energy limitations and unstable performances.
To overcome the challenges of their precursors, Li and Qi Wang, lead author of the study and current Ph.D. student at Ohio State, sought to ensure that their wearable is durable, has a high degree of precision when collecting and analyzing data, and can provide consistent and reliable power.
“Our device is innovative in terms of high resolution, spatial sensing, self-powering capability, and its ability to combine with machine learning algorithms,” Li says. “So, we feel like this research can go further based on the pioneering successes of this field.”
This team’s system is also made unique through its use of AI. Using an advanced machine learning model, the wearable can recognize eight different motion states, including static ones like sitting and standing, to more dynamic movements such as running and squatting.
A particularly notable aspect is the self-powered nature of the insole system. Unlike many wearables reliant on frequent charging or bulky batteries, the innovative embedding of solar cells into footwear harnesses renewable energy seamlessly throughout the day. The ensuing ecological and practical benefits are significant—users can rely on a maintenance-light device that minimizes environmental impact while delivering continuous functionality. This green energy approach is an essential milestone towards sustainable wearable electronics.
While the current iteration already offers robust performance, the research team anticipates several future enhancements. Expanding the dataset to encompass diverse populations is a crucial next step, as individual variations in gait and lifestyle profoundly affect sensor calibration and AI predictive accuracy. By training the machine-learning models on heterogeneous user groups, they aim to bolster generalizability and tailor the wearable’s algorithms to better serve global populations with varying biomechanics, fitness levels, and health statuses.
Researchers expect the technology will likely be available commercially within the next three to five years. The study was recently published in the journal Science Advances.
Sources: Ohio State University and Science Magazine