• Design & Manufacturing
• /
• 제9권3호
• /
• pp.19-23
• /
• 2015

Non-pneumatic wheels have been widely used instead of general tube type wheels beause of many reasons, for example, wheel size, price restriction, heavy-duty problem and so on. Almost small size wheels or casters were non-pneumatic type but structural stability was not certified. This paper presents a double structured non-pneumatic wheel, called "smart caster", which consisted with inner and outer wheels connected by chips, and finite element analysis processes were conducted in order to determine important dwsign factors before actual design for mass production. For structural analysis ABAQUS was used under various boundary conditions with incrementally varied loads until 2,000N. Then structural staility was evaluated according to varied loads below ultimate stress. Generally stresses were concentrated at the lower parts of the wheel, and especially contact parts between wheel and ground. In addition, maximum stress appeared at contact parts between the wheel lower part and chips.

• Design & Manufacturing
• /
• 제12권3호
• /
• pp.48-54
• /
• 2018

This paper presents a numerical study for the development of a low-noise low-vibration industrial wheel for non-pneumatic wheel to significantly reduce vibration and noise. For this, design, injection molding and performance testing were performed. Various geometric shapes and materials were taken into account. For numerical analysis, ANSYS, LS-Dyna, and ABAQUS were used to predict the behavior of the wheel under different loadings based on various design changes. Based on this, 4 prototypes were fabricated by changing the design of wheels and molds, and various vibration and noise tests were carried out. A vibration tester was developed and tested to perform the vibration noise test considering durability. A prototype and test of the final wheel was performed. In the case of the vibration test, the vibration levels were 81.16dB and 80.66dB, which were below the target 90dB. Noise levels were 53.20 dB and 52.55 dB below the target 65dB. In the case of the impact resistance test, it was confirmed that there was no change in appearance after impact. The product weight was measured to be 174g compared to the target of 190g.

• Journal of Platform Technology
• /
• 제11권6호
• /
• pp.34-46
• /
• 2023

자동차 타이어의 휠과 트레드 사이에 탄성중합체 또는 다각형의 스포크를 채우는 방식으로 제작하는 비공기압 타이어는 자동차 관련 학계 및 항공우주 업계의 중요한 연구 주제가 되고 있다. 본 연구에서는 생성형 적대 신경망을 기반으로 비공기압 타이어 디자인을 생성하는 시스템 개발했다. 특히 비공기압 타이어의 종류와 사용 환경, 제작 방식, 공기압 타이어와의 차이점 그리고 스포크 디자인에 따른 하중 전달의 변화 등 디자인에 영향을 미칠만한 변수들에 대한 조사를 실시했다. 이 연구는 OpenCV를 통해 다양한 스포크 형태의 이미지를 만들고, projected GANs에 학습시켜 비공기압 타이어 디자인에 사용될 스포크를 생성했다. 디자인된 비공기압 타이어는 사용 가능 및 불가능으로 레이블링하고, 이를 Vision Transformer 이미지 분류 AI 모델에 학습시켜 분류하도록 하였다. 최종적으로 분류 모델의 평가를 통해 0에 가까운 loss의 수렴, 99%의 정확도를 확인했다. 차후 도형 및 스포크 이미지와 알고리즘을 이용한 디자인이 아닌, 완전 자동화 시스템의 개발과 더 나아가 3D의 물리적 해석 없이 사용 가능한 디자인을 생성하는 것을 목표로 한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제51권12호
• /
• pp.659-663
• /
• 2002

The brake systems of high-speed train are to be equipped with three different brake systems, such as regenerative brake with regenerative feedback in driving car, a pneumatic disc brake, and non-contact linear eddy-current brake(ECB). The regenerative brake and the pneumatic disc brake are acting on the wheels. Their achievable braking force depends on the adhesive coefficient, which is influenced by the weather condition and speed, between the wheel and The linear eddy current brake gets an economical solution in the high-speed train because of the independence of the adhesive coefficient, no maintenance needed. and the good control characteristics. The braking force and the normal force of ECB for korean high-speed train are analysed by the 2D FEM(Finite Element Method). Finally the normal force is compared with the experiential values to verify the analysis.