• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.1569-1570
• /
• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.1253-1254
• /
• 2010

• International Journal of Railway
• /
• v.2 no.1
• /
• pp.8-17
• /
• 2009

The wheelset, its functions and position under the train is the prime safety-critical component. Whether in design, qualification, manufacturing or maintenance, the wheels and axles have been the focus of special attention at SNCF for over 25 years and the French Railways are actively involved in various Research and Development work towards interoperability between the railways, railway reliability and running safety.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.4
• /
• pp.93-99
• /
• 2019

A cross drilling/milling Unit is an important mechanical part which is widely used in many kinds of machining tool, and various gear trains with good accuracy and reliability features are widely used in power transmission systems. A study on a novel power transmission optimization method for driving gear trains in cross drilling/milling units is presented in this paper. A commercial program for gear system simulation, Romax Designer, was used in this research to intuitively observe the gear meshing and the load distribution conditions on the gear teeth. We obtained the optimal modification value through comparing the results of repeated experiments. For validation, optimized gears were fabricated and then measured with a precision tester.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.22 no.3
• /
• pp.364-371
• /
• 2013

Because of the increases in international oil prices and the level of global warming, the automotive industry has much interest in developing green cars with high fuel efficiencies. In addition, researchers in Korea are actively responding to high oil prices and $CO_2$ emission regulations in many ways. One example is, the multi-mode hybrid system, which is being studied to improve its performance. Because a multi-mode hybrid system is able to overcome the weaknesses of a system that uses simple planetary gears, excellent fuel efficiency and driving performances are the key features of the system. This paper analyzes the driving performance of the power-train system of GM-2MT70, which consists of one engine, two electric motors, one simple planetary gear, one double planetary gear, two clutches, and two brakes. The driving performance of the system's steady state is analyzed using performance modeling. The dynamic performance is analyzed using Matlab Simulink.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.15 no.6
• /
• pp.746-753
• /
• 2012

ROK military helicopters are frequently exposed to the hazard situations due to the characteristic of operation. Especially, helicopter accident may lead to critical damage of human and structure. Accordingly, pilots have to train the autorotation procedures and learn the skill to prevent hard landing. In this paper, the behavior of skid gear subject to the helicopter autorotation was conducted by using numerical method. The computer simulation approach by using finite element method was employed to accomplish this goal. Additionally, the behavior of skid gear was evaluated for the different landing conditions. In conclusion, the maximum stress concentration was occurred at the attached area of skid cross-tube to the fuselage. Also, it was revealed that the most proper attitude was level landing to prevent hard landing.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.4
• /
• pp.19-25
• /
• 2016

Using a actuator to which the motor and the gear is applied to the I-PD control method and a dual-loop system to carry out precise position control. I-PD control algorithm performs an operation to reduce the overshoot in the transient response. Accordingly, the actuator obtains a precise position tracking result. Also it utilizes two sensors and dual loops. It reduces the adverse effect on the precise position control that may occur by the end play of the gear train. In this paper, we uses the actuator model applying the BLDC motor and gear in order to determine the position tracking result by the dynamic characteristic change. It was verified by the simulation results.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.10
• /
• pp.4665-4671
• /
• 2013

Engine mounting system is the most responsible system for NVH performance of vehicle. The vibration at idle shake, road shake, Key ON/OFF, gear shift tuned by the engine mount position and stiffness. Previously described Engine mounting system theory investigated and summarized in this paper. Decoupling of the Power train rigid mode and Reducing the angle between Torque-Roll-Axis and Elastic-roll-Axis is starting point of optimization. Multi-optimization analysis was performed because of variety simulation case and FE-model. Eventually, Find the best mount location and the stiffness has improved the performance of the vehicle NVH.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.2
• /
• pp.50-56
• /
• 2007

Wire forming machine is widely used in industries to make a variety of wire products such as coil springs and links. Along with the rapid development of CNC technologies, the usage of wire forming machine varies from single-purpose machinery to universal CNC machinery. Rotating the wires while feeding them simultaneously, we can improve the performance of the machines with aspects of efficient tooling and complicated geometric forming. In this study, a new gear train is developed for the control of both feeding and rotating wires independently at the same time. The developed mechanism has many benefits as following, making more complicated geometric and precision products, easier tooling, and simpler programming.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.1
• /
• pp.66-72
• /
• 2005

The working tactor of this study, an agriculture machine, is consisted of 4 wheel driving system with gear trains and 4-type wheel steering system. Since technological regions for 4 wheel driving system and 4-type wheel steering system are some large, we divide on two studies on 4 wheel driving system and 4-type wheel steering system This study develops transmission and axle that are very important units for strong working operation because the power of tractor is largely affected by transmission and axle. Even if the development of the power train is some common technology, it is very complicated work and needs many experience know-hows. So, for new given specifications fitted to the working tractor, a kind of new agriculture machine, this study haws out processes that are development of assembly drawing and strength analysis through classical method and CAE software for all internal parts and housing cases.