Widely used in the field of biomechanics, pressure mapping has historically provided a visual representation of pressure distribution for the optimization of such products as wheelchair cushions and orthotics. Capacitive tactile sensors are opening the door for the development of a multitude of innovative new medical devices, however, by taking pressure mapping technology to the next level and quantifying the sense of touch.
Pressure mapping systems have proved to be handy tools for identifying pressure “hot spots” in cushion and support system applications as well as for conducting gait analysis. But the information provided by traditional pressure mapping systems has been limited and relatively subjective in terms of interpretation.
Pushing the boundaries of what has previously been achievable with the sense of touch, capacitive tactile sensors, on the other hand, yield quantitative data. Characterized by their precision, stability, and repeatability, these tactile sensor solutions elevate the concept of pressure mapping beyond just a visual representation of pressure distribution to provide actionable data. The ability to obtain such measurements and data, in turn, can enable the development of cutting-edge medical applications that promote early detection of cancer or that measure both blood pressure and pulse, for example.
As we noted in a previous blog post, capacitive tactile sensors are spurring the development of products for early cancer detection that capture the sense of touch to generate real-time, reproducible, objective data. The SureTouch visual mapping system for breast cancer detection and the ProUroScan system for prostate cancer detection both feature probes equipped with tactile sensor arrays that tap into the tactile nature and efficacy of breast self-exams and digital rectal exams, respectively. In each application, however, the sensors measure pressure changes in the target area and convert the data into a real-time, 3-D digital map of the anatomy. By referring to the sophisticated pressure map, clinicians are able to identify abnormalities in the tissue and assess the danger to the patient based on device estimates of the size, shape, hardness, and location of the lesion.
In addition to making their mark on early cancer detection, pressure mapping systems enhanced by the use of capacitive tactile sensing technology have allowed innovative designers to put a new spin on the age-old method of taking one’s pulse. Quantifying blood pressure measurement through pulse pressure measurement can be achieved by pressing a tactile sensor array in a watch-like device against the radial artery as if taking the pulse. The sensors then detect pressure signal changes, and the best sensor element is used to measure the pulse waveform. Digitization of this pressure change is subsequently presented as a pressure waveform, which can be analyzed to determine the hardness of an artery wall and the general health of a patient’s arteries.
Thanks to the incorporation of capacitive tactile sensors, pressure mapping systems have evolved from useful tools into life-saving technologies that improve patient care by quantifying the sense of touch.
