Novel Coplanar Capacitive Force Sensor for Biomedical Applications: A Preliminary Study
Nowadays the world of sensors is gaining a primary importance in the electronics field, thanks to the boom of the smartphones and IoT market. Capacitive sensors are widely involved in the most of applications, from the biomedical to the gaming industry, and they can sense a wide variety of physical quantities. In this work we focused on force sensing capacitive sensors, trying to mix two of the most in-fashion markets, sensors and polymers. Polymers industry is constantly growing and, by the constant synthesis of new bio-based molecules, it will quickly enter the most of the technology markets. We made a soft capacitive force sensor, by inserting a coplanar capacitor in a polymeric wafer structure. The involved technology is derived from the touch-sensing technique, usually involved in appliances’ user interfaces. This sensor is easy to make and cheap, and it was tested with a force of 1 N. It is waterproof and non-sensitive to moisture variation in the outer environment. It shown a sensitivity of 172 fF/N, with a resolution of 80 mN. As it is only a preliminary study, more investigations are needed in order to obtain a deeper characterization versus different environment conditions and with higher force stimuli. It will be also relevant to evaluate the behavior of the sensor by using different polymers.
KeywordsForce sensor Coplanar capacitive sensor Biomedical
- 2.Dai, Y., Abiri, A., Liu, S., Paydar, O., Sohn, H., Dutson, E.P., Grundfest, W.S., Candler, R.N.: Grasper integrated tri-axial force sensor system for robotic minimally invasive surgery. In: Proceedings of the 19th Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBS, pp. 3936–3939 (2017)Google Scholar
- 5.Kim, J., Kwak, Y.H., Kim, W., Park, K., Pak, J.J., Kim, K.: Flexible force sensor based input device for gesture recognition applicable to augmented and virtual realities. In: 2017 14th International Conference on Ubiquitous Robots and Ambient Intelligence, pp. 271–273 (2017)Google Scholar
- 6.Zhuo, B., Chen, S., Guo, X.: Micro structuring polydimethylsiloxane elastomer film with 3D printed mold for low cost and high sensitivity flexible capacitive pressure sensor. In: 2017 IEEE Electron Devices Technology and Manufacturing Conference EDTM 2017—Proceedings, vol. 8, pp. 148–149 (2017)Google Scholar
- 10.Walker, G.: Touch sensing. In: Interactive Displays: Natural Human-Interface Technologies, pp. 27–105 (2014)Google Scholar