Buckling Behavior Analysis of Kirigami Structure Under Tension.

Flexible electronic technology has attracted great interest, where rigid and brittle semiconductor materials can withstand large deformation. In order to improve the stretchability of devices, many novel structures have been designed, such as the classical "wavy" structure, the island-bridge structure, and origami structures that achieve stretchability through creases. However, the stretchability of these structures is still not large enough.

Adaptive Time-Frequency Segment Optimization for Motor Imagery Classification.

Motor imagery (MI)-based brain-computer interface (BCI) has emerged as a crucial method for rehabilitating stroke patients. However, the variability in the time-frequency distribution of MI-electroencephalography (EEG) among individuals limits the generalizability of algorithms that rely on non-customized time-frequency segments. In this study, we propose a novel method for optimizing time-frequency segments of MI-EEG using the sparrow search algorithm (SSA).

Stretchable piezoelectric energy harvesters and self-powered sensors for wearable and implantable devices.

Wearable and implantable bio-integrated electronics have started to gain momentum because of their essential role in improving the quality of life for various patients and healthy individuals. However, their continuous operation is often limited by traditional battery technologies with a limited lifespan, creating a significant challenge for their development. Thus, it is highly desirable to harvest biomechanical energies from human motion for self-powered bio-integrated functional devices.

Transfer Printing and its Applications in Flexible Electronic Devices.

Flexible electronic systems have received increasing attention in the past few decades because of their wide-ranging applications that include the flexible display, eyelike digital camera, skin electronics, and intelligent surgical gloves, among many other health monitoring devices. As one of the most widely used technologies to integrate rigid functional devices with elastomeric substrates for the manufacturing of flexible electronic devices, transfer printing technology has been extensively studied. Though primarily relying on reversible interfacial adhesion, a variety of advanced transfer printing methods have been proposed and demonstrated.

In situ full-field measurement of surface oxidation on Ni-based alloy using high temperature scanning probe microscopy.

We use in situ scanning probe microscopy (SPM) to investigate the high temperature oxidation of Ni-based single crystal alloys at the micro-/nanoscale. SiO micro-pillar arrays were pre-fabricated on the alloy surface as markers before the oxidation experiment. The SPM measurement of the oxidized surface in the vicinity of SiO micro-pillars was conducted real time at temperatures from 300 °C to 800 °C.

Elastomer surfaces with directionally dependent adhesion strength and their use in transfer printing with continuous roll-to-roll applications.

In this paper we present mechanics and materials aspects of elastomeric stamps that have angled features of relief on their surfaces, designed to enable control of adhesion strength by peeling direction, in a way that can be exploited in schemes for deterministic assembly by transfer printing. Detailed mechanics models capture the essential physics of interface adhesion in this system. Experiments with cylindrical stamps that have this design demonstrate their potential for use in a continuous, roller mode of operation.