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With the increasing demand for self-adaptive electronics, stretchable and conformable sensors with high sensitivity, stretchability, and self-adhesive are significant intelligent devices. Here a novel tactile sensor is demonstrated that maintains conformal contact to the object for efficient movement monitoring. The device, which was composed of the "H" well-manicured thermoplastic elastomer (TPE), a rectangular polyvinylidene fluoride (PVDF) film coupled with a silver electrode and clamped into the copper-clad signal line ends, and a "U" shaped super-elastic silica gel layer, provided satisfactory performance. The device was investigated as a dynamic monitoring sensor due to its stretchable and conformal configuration. The mechanical stability and high sensitivity suggested that, when attached to the skin of participants, the sensor detected motion induced strain which was experimentally demonstrated. The results show that the novel biomimetic sensor is effective in monitoring human dynamics, with an accuracy exceeding than 98.3%. The stretchable and conformable sensor is low-cost and nontoxic with potential applications in clinical, conformal detection, and artificial intelligence. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) membranes is a new ferroelectric material exhibiting large piezoelectric properties and has desirable attention in biosensors and the healthcare field. A set of wearable belt was developed using PVDF films of 28 μm as sensitive element and conductive silver as the electrodes. The equipment was designed such that it can sense vibration which could be compatible to those produced by human sleep signal (SS) in a noninvasive way. The prototype of the wearable belt which has 1 × 24 parallel curved slender beams (CSBs) as sensing element using 28 μm thickness PVDF film was fabricated. The element is an assembly of layered media. The base of the sensitive element is a hyperelastic inferior arc polyhedron, on which a PVDF film with silver electrode patches, two 5 μm copper-clad signal interfaces attached to both sides of the PVDF film using conductive adhesive, and a protective surface layer of polyester film for insulation are stacked in sequence. The role of the polyhedron, copper surface end and parallel CSBs design to enhance detection signals, and the capability of the sensor to faithfully detect the SS were experimentally evaluated. Results showed that the new wearable belt (WB) has been manufactured to sense the SS including heartbeat rate (HR), respiration rate (RR) as well as postural signal (PS), and its sensitivity to external mechanical force or vibration is 1.5 times higher than that of a sheet sensitive structure device. All these experimental set-up proposed and developed by us showed the remarkable contribution of the sensitivity and repeatability (98.6%) in SS monitoring depending on signal characteristics such as frequency and amplitude. [ABSTRACT FROM AUTHOR]