IIIT-H makes low-cost flexible sensors to aid in physiotherapy

To restore physical strength in stroke victims or arthritis patients experience muscle weakness, to restore physical exercise such as repetitive movements of the hands in moving an object from one point to another. Different types of exercises are usually prescribed. Researchers at the International Institute of Information Technology-Hyderabad (IIIT-H) PATRIoT Lab have come up with a new-age, low-cost pressure sensor to analyze and identify such activity.

Developing thin, bendable and stretchable circuits for flexible electronics or ‘smart’ applications is one of the fortifications of this group. “In this case, apart from the specific smart properties of the sensor, we also want to cover a large area and try to map the pressure distribution over the entire area,” says Aftab Hussain, principal investigator.

Their use of canvas for essential physical rehabilitation exercises was a sensory mat with designated areas to hold weights. With conductive foam as the main component, this low-cost paper-based 4X4 pressure sensor matrix was fabricated with a layer of paper on each of the top and bottom, sandwiching the copper electrodes.

Each time the foam is pressurized by a patient, there is a decrease in resistance with the application of pressure that can be detected through an external circuit. “We see that if the value of resistance has changed and if it is, we try to explain how much pressure is applied and where it is,” Mr. Hussain explains.

The researchers trained machine learning models to find the load conditions for various resistances. “Neural networks not only help determine if the load was placed in the correct position, but it can also learn from a person’s time-to-time responses,” says Anees Fatma, ‘a low-cost study . ‘Pressure sensor matrix for monitoring activity in stroke patients using artificial intelligence’, which was published in the IEEE Sensor Journal.

The new device has the ability to schedule a physiotherapy session. Mr. Hussain says, “In addition to tracking patients’ progress in terms of accuracy where they are carrying the load, the person can also monitor the time it takes to load, so that we can achieve both load speed and accuracy Can do. “

The product, which uses a very thin-film manufacturing technology, currently costs less than 1,000 1,000, with the team in the process of further reducing costs. “We are investigating whether conductor foam that made sensor pixels possible can be made through synthetic organic chemistry. This will further reduce costs, to better conform the properties of foam to our applications and make them more reliable, ”he adds.