OPTICAL SENSORS IN DEVICES AND SYSTEMS FOR FUNCTIONAL MONITORING

Анотація

In the conditions of the long-term russian aggression against Ukraine, the number of people with disabilities among the military and civilians is rapidly increasing. This creates a critical need for innovative, objective methods for monitoring the rehabilitation process. A key indicator of functional mobility is gait, whose parameters allow the diagnosis of the consequences of musculoskeletal injuries, amputations, and neuromuscular diseases. Traditional methods are often subjective or too expensive, prompting the search for new technological solutions that leverage optical sensors.

The purpose of the work is to study and systematize existing scientific developments on the use of optical sensors in monitoring gait parameters of people with disabilities.

Results. It is studied that gait analysis is considered as a comprehensive study of functional mobility, which plays a key role in the assessment of physical rehabilitation, diagnosis of disorders, and decision-making regarding further rehabilitation interventions. Two main categories of optical systems are analyzed: marker-based, which have ultra-high accuracy (error<1mm), but are limited to laboratory conditions; and marker-free, based on computer vision, which allow for analysis in the natural environment. Particular attention is paid to fiber-optic technologies, in particular sensors based on Bragg gratings and Fabry-Perot interferometers. It is proven that fiber-optic sensors are the most promising for wearable monitoring devices, since they provide non-invasiveness, lack of physical contact, resistance to electromagnetic interference, and high biocompatibility, implementing real-time monitoring.

Conclusions. The use of optical sensors in devices and control systems fundamentally changes the approach to monitoring rehabilitation effects, providing permanent and high-precision monitoring without limiting the mobility of people with disabilities. The use of optical sensors in devices and control systems provides permanent control without limiting motor activity and wireless data transmission. Miniaturization of devices makes them portable and convenient for long-term wear. High accuracy of measurements of kinematic and kinetic parameters is critical for diagnosing disorders and making decisions about further rehabilitation. Prospects for further research into the use of new materials, such as liquid crystal light guides in optical sensors, to create even more adaptive control systems.

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