Conformal manufacturing of soft deformable sensors on the curved surface

Abstract

Health monitoring of structures and people requires the integration of sensors and devices on various 3D curvilinear, hierarchically structured, and even dynamically changing surfaces. Therefore, it is highly desirable to explore conformal manufacturing techniques to fabricate and integrate soft deformable devices on complex 3D curvilinear surfaces. Although planar fabrication methods are not directly suitable to manufacture conformal devices on 3D curvilinear surfaces, they can be combined with stretchable structures and the use of transfer printing or assembly methods to enable the device integration on 3D surfaces. Combined with functional nanomaterials, various direct printing and writing methods have also been developed to fabricate conformal electronics on curved surfaces with intimate contact even over a large area. After a brief summary of the recent advancement of the recent conformal manufacturing techniques, we also discuss the challenges and potential opportunities for future development in this burgeoning field of conformal electronics on complex 3D surfaces.

Asymmetrically Enhanced Coplanar‐Electrode Electroluminescence for Information Encryption and Ultrahighly Stretchable Displays

“…[18] Through the design of new device formats and the introduction of functional materials, several features have been successfully implemented in the devices, including wearable display, [19] information encryption, [20] visualized sensing, [21] soft robots, [8] and motion tracking. [22] Combined with 3D freeform surfaces preparation methods, [23][24][25] the devices can be manufactured on the surface of any objects. These all indicate their immense potential for next-generation optoelectronics.…”

Developing the Nondevelopable: Creating Curved‐Surface Electronics from Nonstretchable Devices

“…Recent progress in this field has brought remarkable advances, leading to a variety of curved devices with unique applications in human-computer interaction, imaging, and environmental sensing. [17][18][19] Currently, deterministically patterned stretchable circuits (e.g., circuits employing an island-bridge structure or a local strain suppression layer) form the basis for the most complex, cutting-edge examples of nondevelopable electronics, including thin-film transistors, [20] ultrasonic transducers, [13] curved imagers, [14,21] and thermoelectric energy harvesters. [22] These devices integrate small chip devices, often made of high-performance electronic materials such as silicon or metal, with wavy or kirigamiinspired interconnects, ensuring that any tensile strain applied to the system is concentrated in the wiring instead of the chips.…”

Multiscale and hierarchical wrinkle enhanced graphene/Ecoflex sensors integrated with human-machine interfaces and cloud-platform

“…Flexible, stretchable and wearable strain sensors have received extensive attention recently because large strains can be applied on the flexible/bendable/stretchable or curved substrates. They effectively change complex mechanical deformations into electrical signals, promising for applications in human health-monitoring systems, wearable internet of things (WIoT), human–machine interaction and soft robotics, etc 1 – 5 . These stretchable/flexible/wearable strain sensors can withstand a much larger strain (up to 500 %) and significant deformation when compared with their rigid counterparts (normally with a strain smaller than 5%) 6 .…”