Cushion pressure sensors
Cushion Pressure Sensors were developed as a part of the UHCI project with the aim to explore the idea of textiles switches in the form of pressure sensors, and using these to control different electronic devices. The electronic circuits are integrated directly into the structure of the fabric, either by weaving or knitting.
The woven pressure sensor is structured as a matrix and consists of two woven layers of parallel conductive lines, where one is placed perpendicularly on top of the other one. When a pressure occurs at a point were two conductive lines cross, it acts like an electrical switch. Each line is connected to a pin on the Arduino Microcontroller and the grid allows the exact pressure point to be identified.
In the knitted version the pressure sensor is made possible by using tuck stitches technique to create a three dimensional surface, with two conductive layers separated by isolated sides. When you press/sit on one of the points where the conductive threads overlap, the electrical circuit is closed and electricity (low voltage) flows through the fabric. By using two different kinds of conductive threads, one highly conductive made of copper and one silver plated with resistive qualities, we can get different resistive values and thereby also determine the position of the contact. All the pressure sensor areas are connected to the Analog inputs of an Arduino. They can be programmed together or individually according to the chosen scenario.
The Cushion Pressure Sensors were exhibited in CeBIT 2014, in Hannover, as a part of a smart-home context.
Two layers for the Matrix.
Exhibition at CeBIT 2014.