• Journal of the Korean Society for Precision Engineering
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• v.32 no.1
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• pp.97-105
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• 2015

Recently, there have been many researches about applications of origami to mechanical engineering, which realizes a 30 sturcture by folding a 20 plane material. With this simple manufacturing process, origami was even adopted by some roboticists as a way to build an entirely new robot with benefits in terms of cost, weight, and structural simplicity In this paper, we propose a new type of a walking robot based on origami structure. Because all the components of the robot that generate gait motion are mechanically connected, it can actually walk fotward with only a single actuator. We also showed the similarity of gait trajectories between a kinematic analysis and the actual gait motion measured by video tracking. This result proved the possibility of designing an origami-based robot with the identical gait trajectory as we plan.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.642-646
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• 2016

A wearable antenna made using conductive tape on paper is presented in this paper. The proposed antenna is composed of a half-wavelength conducting dipole strip and a parasitic conducting strip on the A4 copy paper. The antenna is fed at the center of the dipole strip by an SMA connector. The configuration of the proposed antenna changes according to the origami method. Therefore the radiation patterns of the antenna vary according to whether or not the paper is folded. This approach solves the problem that the reception ratio of the signal decreases because of null points in the antenna radiation pattern. The reflection coefficient and the radiation pattern of the proposed antenna at 900 MHz are evaluated using an EM simulation and measurements. It was shown that the proposed paper antenna has reconfigurable characteristics at 900 MHz when utilizing the origami method.

• Elastomers and Composites
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• v.43 no.2
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• pp.63-71
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• 2008

Up to now, most of researches and practical applications of polymeric elastomers have been focused on rubber, a type of elastomeric materials. Therefore, it has been widely accepted that rubber industry is tire industry. In this review, we would like to illuminate new emerging technologies of elastomers. Among many examples, there are actuators which can transform their mechanical shapes with respect to the surrounding environments. Paper folding (so called "origami" in Japanese) technology can be another good example. Utilizing paper folding technology, three-dimensional (3D) architectures containing multi-functions can be constructed from programmed 2D structures. Elastomer microlens can also be fabricated using lithography technologies combined with chemical reactions.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.4
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• pp.213-220
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• 2023

This paper presents a model simulating the folding process and collision dynamics of "ddakji", a traditional Korean game played using paper tiles (which are also referred to as ddakji). The model uses two A4 sheets as the base materials for ddakji. The folding process involves a series of boundary conditions that transform the wing part of the paper structure into a twisted configuration. A rigid plate boundary condition is also adopted for squeezing, establishing the shape and stress state of the game-ready ddakji through dynamic relaxation analysis. The gaming process analysis involves a forced displacement of the striking ddakji to a predetermined collision position. Collision analysis then follows at a given speed, with the objective of overturning the struck ddakji--a winning condition. A genetic algorithm-based optimization analysis identifies the optimal collision conditions that result in the overturning of the struck ddakji. For efficiency, the collision analysis is divided into two stages, with the second stage carried out only if the first stage predicts a possible overturn. The fitness function for the genetic algorithm during the first stage is the direction cosine of the struck ddakji, whereas in the second stage, it is the inverse of the speed, thus targeting the lowest overall collision speed. Consequently, this analysis provides optimal collision conditions for various compression thicknesses.