Inkjet Printed Pressure Sensing Platform for Postural Imbalance Monitoring

• Published in: IEEE transactions on instrumentation and measurement Vol. 64; no. 10; pp. 2813 - 2820
• Main Authors: Cruz, Silvia, Dias, Daniel, Viana, Julio C., Rocha, Luis A.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-10-2015; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitance; Capacitive sensors; Dielectrics; Electrodes; flexible pressure mapping system (FPMS); Flexible printed circuit board (PCB); Ink; inkjet printing; PEDOT:PSS; Printed circuit boards; Sensors; Substrates; inkjet printing; Flexible printed circuit board (PCB); flexible pressure mapping system (FPMS); PEDOT:PSS
• ISSN: 0018-9456; 1557-9662
• DOI: 10.1109/TIM.2015.2433611

In this paper, a low-cost printed pressure sensing platform is presented. The sensing platform consists of a flexible printed circuit board manufactured using conventional technology (defining the electrical connections and the capacitors dimensions) together with two flexible polymeric membranes made from a thermoplastic elastomer (TPU) printed with conductive ink Poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) for definition of the electrodes. A capacitance-to-digital converter is used to measure the capacitance of the sensors, and a graphical interface in MATLAB allows real-time visualization of data. A prototype sensing platform was designed, fabricated, and tested. The capacitive sensors show a sensitivity of 50 fF/kPa in the region of operation, a noise of 1.2 fF/\surd Hz, and a stability of better than 1.5% full scale. The proposed pressure sensor platform has the potential to integrate multiple sensing parameters for ubiquitous environment monitoring.