Amplifying Touch Using 3D ZnO Tetrapods for Tactile and Haptic Intelligence

In the era of virtual and augmented reality, the quest for wearable tactile sensors that can relay and resolve physical interactions akin to the human sensory receptors and provide haptic feedback are becoming increasingly important. Inclusion of pressure sensors in soft and textured forms can also help bionic devices, and aid positively in diagnostics and rehabilitation of gait movement and plantar fasciitis in geriatric patients[1].Their multifunctional role is often suited to double up as energy-harvesters- capable of converting external kinetic energy into electrical energy via microstructural changes [2].<br/>In this work, we present piezoelectric properties of a composite film of Polyvinylidene fluoride (PVDF) and 3D Zinc oxide tetrapods (ZnT). Zinc oxides are emerging as ideal materials for piezoelectric applications due to their superior piezoelectric properties, flexibility, and stability. PVDF stands out for its flexibility and biocompatibility. By integrating these materials, we created tactile sensors that are not only highly sensitive but also serve as energy harvestor, making them suitable for self-powered wearable sensing applications[3]. Electrical characterization of these composite devices shows the piezoelectric voltage produced increases as a function of ZnT loading. Their operational stability, reliability and effectiveness in monitoring different types of physical interactions including whole body weight bearing and detection of foot movement are examined. These advancements could pave the way for the integration of flexible, highly sensitive, and self-powered pressure sensors into future healthcare, haptic feedback systems, and robotic technologies[4].<br/><br/>Literature<br/><br/>[1] A.L. Hatton, M.D. Chatfield, E.M. Gane, J.N. Maharaj, T. Cattagni, J. Burns, J. Paton, K. Rome, G. Kerr, The effects of wearing textured versus smooth shoe insoles for 4-weeks in people with diabetic peripheral neuropathy: a randomised controlled trial, Disability and Rehabilitation 1-11.<br/>[2] A. Cafarelli, A. Marino, L. Vannozzi, J. Puigmartí-Luis, S. Pané, G. Ciofani, L. Ricotti, Piezoelectric Nanomaterials Activated by Ultrasound: The Pathway from Discovery to Future Clinical Adoption, ACS Nano 15(7) (2021) 11066-11086.<br/>[3] M. Kielar, T. Hamid, L. Wu, F. Windels, P. Sah, A.K. Pandey, Organic Optoelectronic Diodes as Tactile Sensors for Soft-Touch Applications, ACS Appl Mater Interfaces 11(24) (2019) 21775-21783.<br/>[4] J.V. Vaghasiya, C.C. Mayorga-Martinez, M. Pumera, Wearable sensors for telehealth based on emerging materials and nanoarchitectonics, npj Flexible Electronics 7(1) (2023) 26.