Digital printing technologies—including inkjet printing, aerosol jet printing, and electrohydrodynamic jet printing—have emerged as promising strategies for next-generation electronic devices. However, the weak adhesion between printed electrodes and substrates can lead to electrode delamination, thereby compromising device reliability and lifetime. In this study, a dielectric interlayer was introduced to improve the adhesion of silver (Ag) mesh electrodes on glass, polyethersulfone film, and polyimide film substrates. The optimized electrode on PES film achieved an optical transmittance of 83% at 550 nm and line resistance of 0.3 Ω, confirming its suitability as a transparent electrode. The incorporation of the interlayer also enhanced the adhesion and mechanical flexibility across all substrates. Moreover, the printed electrodes exhibited uniform surface heating under an applied bias (≤DC 3 V), and their feasibility as low-power flexible transparent heaters was experimentally demonstrated. These findings present a simple and effective printing strategy for fabricating robust and multifunctional electrodes, offering enormous potential for the realization of future flexible and transparent electronic systems.
31 May 2022 in Journal of Institute of Control, Robotics and Systems
Recently, the research on marine IoT (Internet of Things) has been diversified. The demand for marine robots capable of responding to advanced missions has been increasing. However, it is difficult to objectively evaluate the performance of marine robots. This is mainly because several problems hinder this evaluation, such as high-weight and large-scale marine robots, uncertainty in marine environmental conditions, and performance evaluation costs. Thus, KIOST(Korea Institute of Ocean Science and Technology) is building the Jang Yeongsil as a ship that can professionally conduct field tests and evaluations at sea. Additionally, they are conducting research activities to evaluate the objective performance of marine robots. Therefore, in this paper, performance evaluation trends of land/marine robots are analyzed, and evaluation items for test evaluation of marine robots are presented based on this analysis. Using depth keeping, the results were verified through a third-party witness verification. The third-party witness test results demonstrate the test procedure’s reasonableness.
30 June 2022 in Journal of Institute of Control, Robotics and Systems
Recently, research and development on underwater cities have emerged. Hence, research equipment to investigate the characteristics of the seabed is also diversifying. Existing underwater ground survey equipment faces the problem where a large system, high cost, and available ships are limited. Therefore, the FFCPT (Free-Fall Cone Penetration Test) is emerging as a realistic alternative. KIOST in Korea is developing an FFCPT, intending to have a depth of 200m or more and a weight of less than 100㎏. When operating the FFCPT, heavy-load work such as loading on a ship, moving, dropping, and extruding from the seabed is required. It is essential to perform work according to the standard operating procedure (SOP) in consideration of safety. However, there are no studies on SOPs for an FFCPT. Therefore, in this paper, an SOP for an FFCPT was proposed. The result of the total resistance test of the seabed demonstrates the effectiveness of the proposed SOP. Furthermore, we could generalize our work using an FFCPT based on the proposed SOP.
30 June 2020 in Journal of Ocean Engineering and Technology