The aim of the project "High tech sensor technology for the challenge of demographic change in Saxony", which is based at the Professorship of Electrical Measurements and Sensor Technology (Prof. Dr. Olfa Kanoun) at Chemnitz University of Technology, was to develop sensor mats to support the treatment of pressure ulcers in patients with diabetes mellitus. A special novelty of this project is the embedding of carbon nanotubes (CNT) based sensors that can measure pressure with high precision. The use of CNTs for the production of pressure sensors is a unique selling point of "SenseCare" for the healthcare and medical sector.
With their embedded sensor technology, these sensor mats are able to detect changes in temperature, pressure and humidity when they come into contact with the human body. For this purpose, the project team produced ultra-thin sensors in the micrometer range. For comparison: human hair is between 30 and 120 micrometers thick. The research team developed the sensors on the basis of CNTs, which in turn are printed on polymer films. These sensors are suitable as aids in health care and for monitoring patients with certain health problems such as diabetes-related ulcers or non-healing wounds.
The operating principle of CNT-based pressure sensors is based on the measurable change in the electrical resistance of the sensor material when pressure, temperature and humidity change.
Two prototypes were developed for testing the sensors: a mat and a sole. The mat can be double-layered, i.e. it works on both sides and is capable of sensing temperature and humidity on one side and pressure on the other. The insole, on the other hand, can sense pressure at specific anatomical points, for example the ball of the foot and the heel. This data is measured in real time and can be displayed via a graphical user interface. This is of particular interest to diabetes mellitus patients. In the laboratory this is done on the desktop, but mobile use via an app is conceivable and feasible.
The sensor insole can be used with patients to detect increased pressure on the foot to prevent foot injuries. Experienced users ensure that the pressure is distributed evenly. Patients with diabetes mellitus receive feedback via the ultra-thin shoe sole to correct their gait. After miniaturisation, the sensor mat can be used in the care sector to prevent bed sores and pressure sores in bedridden senior citizens or patients.
The developments in sensor technology achieved in "SenseCare" have a lot of potential because demographic change and the increasing proportion of diabetes mellitus make user-friendly solutions a necessity in order to enable more treatment and quality of life for those affected, their relatives and caregivers. This technology can prevent further physical damage and relieve the burden on caregivers. With its extremely thin sensors, the developed sensor solution is cost-effective and durable, thus representing an advance over existing sensor systems.
At the leading trade fair for sensors and measuring systems "Sensor+Test" last year, the sensor mat was presented to a specialist audience and received very positive reactions from the participants.