Development and Assessment of Highly Sensitive, Economically Viable, and Environmentally Sustainable Fabric-Based Flexible Capacitive Pressure Sensors

Subrata Pandey; Soumitra Kumar Mandal

doi:10.51173/jt.v7i1.2626

Authors

Subrata Pandey National Institute of Technical Teachers, Training and Research, Kolkata, India
Soumitra Kumar Mandal National Institute of Technical Teachers, Training and Research, Kolkata, India

DOI:

https://doi.org/10.51173/jt.v7i1.2626

Keywords:

Capacitive Pressure Sensor, Flexible Pressure Sensor, Polyurethane, Silver Metalized Fabric, Robot Skin

Abstract

Flexible capacitive pressure sensors offer unparalleled benefits—malleability, stability, simplicity, low power consumption, and minimal sensitivity to temperature fluctuations. Yet, their expensive materials, complex, and environmentally detrimental manufacturing processes impede their widespread adoption. This study unveils a cost-effective, simple, and environmentally sustainable method to fabricate highly sensitive flexible capacitive pressure sensors that outperform costly sensors manufactured using unsustainable materials. By sandwiching a flexible polyurethane (PU) sheet between two silver-metallized fabrics (SMF) and securing them with polyethylene adhesive tape (PAT), we have eliminated the need for expensive and specialized equipment and methods. Crafting sensors of varying dimensions is now as simple as cutting fabric and PU sheets with everyday tools. The key to the sensor's performance lies in the exceptional deformability of the PU layer under applied pressure, resulting in an impressive sensitivity of 0.377358 kPa⁻¹.This surpasses the sensitivity of existing non-eco-friendly and expensive sensors reported in the literature. Additionally, the sensor exhibits excellent pressure resolution and high repeatability. Our sensor accurately detects intricate human movements like palm bends and taps, showcasing its potential across diverse applications—from robotic skins to smart wearables and seamless human-computer interactions. With a production cost as low as 0.34 USD per sensor —significantly lower than the costs of sensors reported in the literature—this study signals a significant advancement in flexible sensor technology, combining affordability, simplicity and sustainability with exceptional performance.

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Author Biographies

Subrata Pandey, National Institute of Technical Teachers, Training and Research, Kolkata, India

Subrata Pandey received his B.Tech in Electrical Engineering from Birbhum Institute of Engineering and Technology, West Bengal, India, in 2014 and his M.Tech in Mechatronics Engineering from National Institute of Technical Teachers’ Training and Research, Kolkata, West Bengal, India, in 2023, both of which are under the Maulana Abul Kalam Azad University of Technology, West Bengal. He served as a Teaching Associate in the Department of Electrical Engineering at Seacom Skills University, West Bengal, India, from 2018 to 2022. He served as a Project Associate in the Department of Underwater Robotics and Autonomous Systems Group at the Council of Scientific & Industrial Research-CMERI, Durgapur, West Bengal, India for more than one year from 2023 to 2024. Currently, he is pursuing his PhD from the National Institute of Technology, Durgapur. His research interests encompass flexible sensors, bioinspired robotics, control systems and the application of bioinspired optimization methods.

Soumitra Kumar Mandal, National Institute of Technical Teachers, Training and Research, Kolkata, India

Soumitra Kumar Mandal obtained a BE (Electrical Engineering) from Bengal Engineering College, Shibpur, Calcutta University, and an MTech (Electrical Engineering) with specialisation in Power Electronics from Institute of Technology, Banaras Hindu University, Varanasi. Thereafter, he obtained a PhD degree from Punjab University, Chandigarh. He started his career as a lecturer of electrical engineering at SSGM College of Engineering, Shegaon. Later he joined Punjab Engineering College, Chandigarh, as a lecturer, and served there from March 1999 to January 2004. In February 2004, he joined National Institute of Technical Teachers’ Training and Research, Kolkata, and is presently Associate Professor of Electrical Engineering at this institute. Prof. Mandal is also a life member of ISTE and a member of IE. Throughout his academic career, he has published twenty research papers in national and international journals and presented many papers in national and international conferences. His research interests are in the field of computer-controlled drives, microprocessor-and-microcontroller-based system design, embedded system design and neuro-fuzzy computing.

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