Nature-inspired rollable electronics

Abstract

Inspired by the rolling mechanism of the proboscis of a butterfly, rollable electronics that can be rolled and unrolled to a great extent on demand are developed. Generally, electronic devices that are attached to various surfaces to acquire biosignals require mechanical flexibility and sufficient adhesive force. The rollable platform provides sufficient force that grips onto the entire target surface without destroying the target organ. To prove the versatility of our device not only in gripping and detecting biosignals from micro objects but also in performing a variety of functions, thin-film electronics including a heater, strain sensor and temperature sensor are constructed on the rollable platform, and it is confirmed that all the electronics operate normally in the rolled and unrolled states without breakdown. Then, micro bio-objects are gripped by using the rollable platform, and their tiny motions are successfully detected with the sensor on the platform. Furthermore, the detection of the pulse wave signals of swine under diverse experimental conditions is successfully conducted by rolling up the rollable system around the blood vessel of the swine, the result of which proves the feasibility of a rollable platform as a biomedical device.

Vital signal sensing and manipulation of a microscale organ with a multifunctional soft gripper

“…To measure accurate signals from the artery system, the soft gripper has to make conformal contact with the artificial blood vessel and remain fixed (Fig. 4D) ( 28 ). The inner fluid pressure (IFP) of the artificial human artery system could be measured through the crack-based strain sensor (Fig.…”

Materials and Devices for Stretchable Electronic Nerve Interfaces

“…A major design choice is the encapsulation material of the PNI. 73 The encapsulation or support can dominate the PNIs mechanical properties and is commonly made either of a thick layer of silicone [74][75][76][77][78] , or polyimide [79][80][81][82][83][84][85][86] and parylene-C [87][88][89][90][91][92][93][94][95][96] in case of thin film devices. Based on this principle, there are three basic device designs employed for PNIs depicted in Figure 10: extraneural, intraneural and regenerative.…”

A Pressure-Insensitive Self-Attachable Flexible Strain Sensor with Bioinspired Adhesive and Active CNT Layers

“…With an increase in the CNT coating dose, the adhesion strength of the ECM rapidly decreased and reached almost "zero". By contrast, SCM maintained its strong adhesion strength while the sheet resistance significantly decreased from ~10 7 to ~10 4 Ω sq −1 , when the coating dose of the MWCNT layer was increased (Figure S2a). Based on the measured sheet resistance and thickness of the MWCNT layer as a function of the coating dose of the MWCNT, we evaluated the conductivity (calculated by 1/sheet resistance × 1/thickness) of the MWCNT layer.…”

“…Recently, flexible tactile sensors that can transform mechanical stimuli into electrical or optical signals have been actively developed as a key component of emerging human-robot interactive systems [1,2], wearable electronics [3][4][5], healthcare devices [6,7], and prosthetics [8,9]. For the successful application of flexible mechanical sensors in these innovative systems, they should have high sensitivity over a specific detection range on diverse planar and even nonplanar target objects [3,7,10].…”

“…Recently, flexible tactile sensors that can transform mechanical stimuli into electrical or optical signals have been actively developed as a key component of emerging human-robot interactive systems [1,2], wearable electronics [3][4][5], healthcare devices [6,7], and prosthetics [8,9]. For the successful application of flexible mechanical sensors in these innovative systems, they should have high sensitivity over a specific detection range on diverse planar and even nonplanar target objects [3,7,10]. To achieve this requirement, low-dimensional nanomaterials such as carbon nanotubes (CNTs) [11,12], nanowires [13][14][15][16], nanoparticles [17][18][19], and graphene [20][21][22] have been utilized as active sensing components of flexible sensors based on different transduction modes of capacitance [22], piezoelectricity [16], piezoresistivity [23], and triboelectricity [12,24], owing to their excellent mechanical, electrical, and optical properties.…”