An in-wheel motor is a system in which a drive motor is mounted inside a wheel along with a braking device, and the motor inside the wheel directly drives the wheel. An SR motor drive in replace of the conventional PM motor drive for in-wheel motor system has been proposed and analyzed. Two different types of converters were selected and their feasibility in terms of different current control schemes was analyzed and validated through dynamic simulation using PSIM software.

A retractable bollard system has been used for the traffic control and protection of important facilities such as electric power plants, airports and government buildings etc. The power source of the driving unit of the conventional protective bollard system is on hydraulic or pneumatic system which has several disadvantages compared to an electric driven unit. In this research, an electric driven unit for an automatic retractable bollard is designed and developed to replace the conventional hydraulic and pneumatic driven type. For the reliability test of the developed electric driven unit, a field test has been successfully done. A case study was conducted to develop a defensive retractive bollard which the target performance is 9sec. and 7sec. on its raising and descending operation speed respectively with 750mm in stroke. The required time limit was fully satisfied as the time measured from the experiment were 7.5sec and 5.5sec for each operation. The developed unit also passed 364,000 cycles of operation without any serious malfunctions at the load test proving its reliability. The design theory and process of an electric driven unit of the automatic retractable bollard presented in this article is believed to be very useful contribution and design tool in advancing the physical security industry.

To overcome recent emission regulation, various hybrid systems are being developed. In the E-4WD(electric four wheel drive) system, the engine and transmission drive the front wheel, electric motor and single reduction gear drive the rear wheel. As the gear ratio of the reduction gear set determines the electric motor's operating point, the gear ratio is important to enhancement efficiency of hybrid system. This study is to analyze motor reduction gear ratio's influence on E-4WD hybrid system for optimized efficiency and driving performance. Fuel economy, operating point of power source and hybrid mode are analyzed using simulation developed with dynamic programming method.

Engine power of industrial vehicle is used to control the driving load, steering load and operating load. In other words, one power source need to transmit part of power through several power transmission paths. To achieve this performance, we consider a gear box which have one input shaft and several output shaft. In this study, the performance of gear box is analyzed to find out the reliable test process in dynamometer. With test results, the validity of study is verified.

This paper presents new type magnetostrictive optical systems. The suggested wireless optical systems are developed by using two types of magnetostrictive thin film actuators. The first is a seesaw type wireless-controlled compact optical switch, and another is a comb type TbDyFeNi thin film actuator by silicon micromachining techniques with DC magnetron sputtering. In the seesaw type, TbDyFe films are selectively deposited on the micromachined switch matrix. For the optical switching operation, switch is arranged in a 1×2 array (mirror size of 5mm × 800μm × 50μm) and has different length from the supporting point. Mirrors are also actuated by externally applied magnetic fields up to 0.5T. In the comb type, the effect of Ni content on the magneto-mechanical properties of the Tb0.24Dy0.76Fe2 system is investigated with the effect of deposited film thickness of TbDyFeNi on silicon substrate for wireless microactuator. As results, magneto-mechanical characteristics are investigated. using magnetization and deflected angle variation

Flexible Driving System(FDS)는 제조업(주로 자동차 생산공장 및 전자제품 생산공장, 식품공장 등) 생산공장에서 사용되는 무인 자동화 운반설비를 말한다. 지금으로부터 200년전 James Ford가 개발했던 공장자동화의 역사는 산업혁명을 거치면서 발전을 거듭하였으며 최근에는 작업자의 안전 및 돌발적 사고로 인한 생산성 급감이 생산공장에서는 중요한 이슈로 떠오르고 있으며, 이를 보완하기 위한 기존 시스템의 운반설비 시스템에 더욱 스마트한 기능을 더한 자동화설비에 대한 필요성이 증대되었다. 이를 위해 먼저 현재 생산중인 제어부 전차반의 크기를 기존 대비 30 % 정도 compact하게 재설계하여 소형화함으로써 종래의 기어방식의 컨베이어 시스템의 대용으로 사용되며, 향후 전문화 될 경우 Electrical Moving System(EMS)가 널리 사용되게 될 전망이다.

본 연구는 수산 폐기물인 굴패각을 공조시스템의 수분 흡착제로 사용하기 위한 가능성을 실험을 통해 살펴본 기초적인 연구이다. 연구의 주된 목적은 굴패각의 제습성능과 열전소자의 냉각효과를 파악하는 것이며 본 연구를 통해 굴패각은 공조시스템 내에서 사용가능한 수분 흡착제로서의 성능을 충분히 가지고 있으며, 또한 냉각효과를 통해 흡착성능을 크게 향상시킬 수 있다는 것을 알았다. 본 시스템은 신재생에너지인 태양광을 이용하기 때문에 시스템의 구동에 필요한 다른 전원은 필요 없어 환경적으로도 매우 바람직한 연구이다.

Ground source heat pumps are clean, energy-efficient and environment-friendly systems. Although the initial cost of ground source heat pump system is higher than that of air source heat pump, it is now widely accepted as an economical system since the installation cost can be returned within an short period of time due to its high efficiency. In the present study, performances of ground source compound hybrid heat pump system applied to a resort building are simulated. The system design and operation process appropriate for the surrounding circumstance guarantee the high benefit of the heat pump system applied to a resort building. If among several renewable energy sources, ground, river, sea, waste water source are chosen as available alternative energies are combined, COP of the system can be increased largely and hybrid heat pump system can reduced the fuel cost.

섬유기계산업은 생산성의 극대화를 위해 고속/정밀화를 추구하고 있으며 수요자의 요구에 따라 높은 내구성과 안정성, 신뢰성을 가진 기계를 요구하고 있다 본 연구에서는 워터제트직기를 대상으로 실제 운전 시 구동계에 토크센서를 부착하여 모듈별로 직기에 영향을 미치는 부하량을 측정 및 분석하였다 또한, 워터제트직기에 대한 동역학적 해석을 수행한 결과와 비교함으로서 섬유기계의 구동계에 대한 토크와 진동에 대한 계측 및 분석기술을 개발하고, 내구성과 안정성이 뛰어난 고부가가치의 섬유기계 개발에 대한 기초자료를 제시하였다.

Mechanical systems using tendon-driven actuators have been widely used for bionic robot arms because not only the tendon based actuating system enables the design of robot arm to be very efficient, but also the system is very similar to the mechanism of the human body’s operation. The tendon-driven actuator, however, has a drawback caused by the friction force of the sheath. Controlling the system without considering the friction force between the sheath and the tendon could result in a failure to achieve the desired dynamic behaviors. In this study, a mathematical model was introduced to determine the friction force that is changed according to the geometrical pathway of the tendon-sheath, and the model parameters for the friction model were estimated by analyzing the data obtained from dedicated tests designed for evaluating the friction forces. Based on the results, it is possible to appropriately predict the friction force by using the information on the pathway of the tendon.

The backdrivable servovalve is a desirable component for force and interaction control of hydraulic actuation systems because it provides direct force generation mechanical impedance reduction by its own inherent backdrivability. However, high parametric uncertainty and friction effects inside the hydraulic actuation system significantly degrade its advantage. To solve this problem, this letter presents a disturbance-adaptive robust internal-loop compensator (DA-RIC) to generate ideal interactive control performance from the backdrivable-servovalve-based system. The proposed control combines a robust internal-loop compensator structure (RIC) with an explicit disturbance estimator designed for asymptotic disturbance tracking, such that the controlled system provide stable and ideal dynamic behavior for impedance control, while completely compensating the disturbance effects. With the aid of a backdrivable servovalve, we show that the proposed control structure can be implemented based on a simplified nominal model, and the controller enables implementation without accurate knowledge of the target system parameters and disturbances. The performance and properties of the proposed controller are verified by simulation and experiments.