Integrating sensors into assistive devices

In this project case, we built demonstrators and explored sensors that can be applied in assistive devices. Concrete applications include measuring ground reaction force under a crutch, pressure distribution in transfer slings, wheelchair cushions, and seating or lying orthoses, as well as pressure measurement in a shoe insole or scoliosis brace.

We built a demonstrator and investigated angle measurement systems that can be used to measure joint angles in, for example, knee braces and ankle-foot orthoses, as well as to measure joint angles in individuals with spasticity.

In this project case, demonstrators were built to detect movement, but also to monitor changes in pressure, temperature, and humidity. These parameters are important in pressure ulcer management. Pressure ulcer management means preventing bedsores, but also, for example, avoiding wounds at pressure points on the foot (diabetic foot).

This project case explores sensor systems that could be applied in items such as lifting slings, shoes for diabetics, and posture-correcting suits. It also looked into new developments in sensors that measure shear forces, as these—alongside temperature, pressure, and humidity—provide another important indication for the development of pressure ulcers.

In this project case, a radar sensor was developed that can detect heart rate and breathing without physical contact. This sensor is linked to a care alert system, allowing patients and residents to be monitored contactlessly—for example, when standing at a standing table or when sitting/lying in a seating/lying orthosis.

The time an assistive device is worn by the patient provides an indication of therapy adherence. This wear time can be determined by recording, for example, temperature or pressure patterns using sensors integrated into the device (such as a knee brace, scoliosis corset, AFO, insole, or orthopedic shoe). Within this project case, we investigated commercially available sensors and built demonstrators that allow wear time to be fed back in various ways to the treating physician/therapist, provider, or patient.

Through Jessa Hospital and ReumaNet.be, we conducted a survey among users of orthoses and orthopedic shoes. We explored barriers and facilitating factors related to the use of their assistive devices. We also asked about their attitudes toward integrating sensors into these devices. The results of this survey were presented at the 10th Dutch Bio-Medical Engineering Conference. You can download the scientific poster here.