A study on the optimization method for a multi-body system using the response surface analysis

An optimization method, which minimizes the characteristic value of a system using response surface analysis, is presented. Plackett-Burman design is used as a screening method. Using the response surface analysis, second order recursive model function is estimated as an objective function. To verify the reliability of the model function, an F-test based on the analysis of variances table is used. Lastly, the sequential quadratic-programming method is used to find the value of design parameters. By applying the preceding procedure to a multi-body dynamic model, the optimization process presented in this study is verified. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Sung Pil Jung received a B.S. degree in Mechanical Engineering from Ajou University in 2006. Currently he is a Ph.D candidate at Ajou University in Suwon, Korea. Mr. Jung’s research interests are in the area of multi-body & structural dynamics, optimization and computer aided engineering. Tae Won Park received a B.S. degree in Mechanical Engineering from Seoul University. He then went on to receive his M.S. and Ph.D. degrees from the University of Iowa. Dr. Park is currently a Professor at the School of Mechanical Engineering at Ajou University in Suwon, Korea.     

Optimization of the industrial guide-way vehicle to improve the running stability

This paper presents an optimization of the industrial guide-way vehicle that aims to improve running stability at increased speeds. A guide-way vehicle was used to transfer products in various manufacturing industries. Using Design Of Experiment(D.O.E.), the design prototype was optimized. The improved design prototype and its design parameters were obtained by a case study determined by the engineering discussion. The computational model for the optimization was validated by correlation with the test results. Through this procedure, the optimization method presented in this paper has been proven to be effective. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Kab-Jin Jun received a B.S. degree in Mechanical Engineering from Ajou University in 2005. He is currently a Ph.D candidate at Ajou University in Suwon, Korea. His research interests are in the area of optimization, vehicle dynamics. Tae Won Park received a B.S. degree in Mechanical Engineering from Seoul University. He then went on to receive his M.S. and Ph.D. degrees from the University of Iowa. Dr. Park is currently a Professor at the School of Mechanical Engineering at Ajou University in Suwon, Korea. Sung Pil Jung is currently a Ph.D candidate at Ajou University in Suwon, Korea. Mr. Jung’s research interests are in the area of multi-body & structural dynamics, optimization and computer aided engineering.     

The articulated vehicle dynamic analysis using the AWS (All Wheel Steering) ECU (Electronic Control Unit) test

An AWS (all-wheel-steering) system is applied to the articulated vehicle to satisfy the required steering performance. AWS ECU (electronic control unit) controls the hydraulic actuator according to vehicle driving environment, such as driver steering angle, articulating angle, and vehicle velocity. In this paper, the test platform devloped for the AWS ECU black box test in an HIL( hardware in the loop) environment is explained. Using the developed test platform, the control algorithm of the AWS ECU can be evaluated under the virtual driving condition of the articulated vehicle. Also, the maneuver of the vehicle is investigated by using the developed AWS ECU test. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Sooho Lee received a B.S. degree in Mechanical Engineering from Ajou University in 2003. He then went on to receive his M.S. degree from Ajou University in 2005. Mr. Lee is currently a Ph.D student in the School of Mechanical Engineering at Ajou University in Suwon, Korea. His research interests are in the area of dynamics, vehicle dynamics, control and HILS ( hardware in the loop simulation).     

三维大变形梁系统的动力学建模与仿真*

对三维大变形柔性梁系统的动力学建模和仿真进行了研究。采用绝对节点坐标法描述柔性体的大变形和大位移运动,并由此建立三维大变形柔性梁系统的动力学模型。在此动力学模型基础上,编制动力学仿真软件,实现了对三维大变形柔性梁系统的动力学仿真。给出了两个动力学仿真算例。第一个对柔性单摆自由下落进行了动力学仿真,并与现有文献结果相比较,验证了模型的正确性。第二个对空间柔性双摆的自由下落过程进行了动力学仿真,并将模型计算的结果与使用ADAMS软件计算的结果进行比较。研究结果表明,ADAMS在计算大变形物体动力学时具有局限性,而所得的模型能够有效地对三维大变形柔性梁系统的动力学进行仿真解决这类动力学问题。     

Measurement and correlation of high frequency behaviors of a very flexible beam undergoing large deformation

A correlation method of high frequency behaviors of a very flexible beam undergoing large displacement is presented. The suggested method based on the experimental modal analysis leads to more accurate correlation results because it directly uses the modal parameters of each mode achieved from experiment. First, the modal testing and the parameter identification method are suggested for flexible multibody dynamics. Due to the flexibility of a very thin beam, traditional testing methods such as impact hammer or contact type accelerometer are not working well. The suggested measurement with high speed camera, even though the test beam is very flexible, is working well. Using measurements with a high speed camera, modal properties until the 5th mode are measured. And After measuring each damping ratio until the 5th mode, a generic damping model is constructed using inverse modal transformation technique. It’s very interesting that the modal transformation technique can be also applied even in the ANCF simulation which uses the global displacement and finite slope as the nodal coordinates. The results of experiment and simulation are compared until the 5th mode frequency, respectively, by using ANCF forced vibration analysis. Through comparison between numerical simulation and experiment, this study showed that the proposed generic damping matrix, modal testing and parameter identification method is very proper in flexible multibody dynamic problems undergoing large deformation.     

Recursive Newton–Euler formulation for flexible dynamic manufacturing analysis of open-loop robotic systems

The main objective of this paper is to develop a recursive formulation for the flexible dynamic manufacturing analysis of open-loop robotic systems. The nonlinear generalized Newton–Euler equations are used for flexible bodies that undergo large translational and rotational displacements. These equations are formulated in terms of a set of time invariant scalars, vectors and matrices that depend on the spatial coordinates as well as the assumed displacement fields. These time invariant quantities represent the dynamic manufacturing couplings between the rigid body motion and elastic deformation. This formulation applies recursive procedures with the generalized Newton–Euler equations for flexible bodies to obtain a large, loosely coupled system equation describing motion in flexible manufacturing systems. The techniques used to solve the system equations can be implemented in any computer system. The algorithms presented in this investigation are illustrated using cylindrical joints for open-loop robotic systems, which can be easily extended to revolute, slider and rigid joints. The recursive Newton–Euler formulation developed in this paper is demonstrated with a robotic system using cylindrical mechanical joints.     

A study on the dynamic performance of the 200km/h Korean tilting train by means of roller rig test

The dynamic performances of newly developed railway vehicles should be carefully verified step by step, from computer simulation through the laboratory-based roller rig test to the main line trial running test. The laboratory-based roller rig test is an effective and safe way to evaluate the dynamic characteristics such as high speed, ride comfort and dynamic behaviors. This experimental research was performed to evaluate the dynamic performances of the 200 km/h Korean tilting train, ‘Hanvit200’, by means of a full scale roller rig test. The newly developed tilting mechanism and stabilizer were included in the tilting bogie to satisfy both the conflicting requirements of higher stability and higher curving performance. This paper shows the roller rig test results and the effectiveness of tilting bogie design. Included are the roller rig test results of various kinds of conditions such as tare and fully laden load case, normal and failed case of important bogie components, linear and non-linear critical speed. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Nam-Po Kim received a B.S. degree in Mechanical Engineering from Ajou University in 1985. He then went on to receive his M.S. and Ph.D. degrees from Ajou University in 1992 and 2008, respectively. Dr. Kim is currently a principal researcher at the department of vehicle dynamics and propulsion system at Korea Rail Road Research Institute in Uiwang, Korea. His research interests are in the area of railway vehicle dynamics, active control of running gear for railway vehicle and vehicle system engineering.     

Recursive newton-euler formulation for flexible dynamic manufacturing analysis of open-loop robotic systems

The main objective of this paper is to develop a recursive formulation for the flexible dynamic manufacturing analysis of open-loop robotic systems. The nonlinear generalized Newton-Euler equations are used for flexible bodies that undergo large translational and rotational displacements. These equations are formulated in terms of a set of time invariant scalars, vectors and matrices that depend on the spatial coordinates as well as the assumed displacement fields. These time invariant quantities represent the dynamic manufacturing couplings between the rigid body motion and elastic deformation. This formulation applies recursive procedures with the generalized Newton-Euler equations for flexible bodies to obtain a large, loosely coupled system equation describing motion in flexible manufacturing systems. The techniques used to solve the system equations can be implemented in any computer system. The algorithms presented in this investigation are illustrated using cylindrical joints for open-loop robotic systems, which can be easily extended to revolute, slider and rigid joints. The recursive Newton-Euler formulation developed in this paper is demonstrated with a robotic system using cylindrical mechanical joints.     

A New Flexible Multibody Dynamics Analysis Methodology of Deployable Structures with Scissor-Like Elements

There are vast constraint equations in conventional dynamics analysis of deployable structures,which lead to differential-algebraic equations(DAEs) solved hard.To reduce the difficulty of solving and the amount of equations,a new flexible multibody dynamics analysis methodology of deployable structures with scissor-like elements(SLEs) is presented.Firstly,a precise model of a flexible bar of SLE is established by the higher order shear deformable beam element based on the absolute nodal coordinate formulation(ANCF),and the master/slave freedom method is used to obtain the dynamics equations of SLEs without constraint equations.Secondly,according to features of deployable structures,the specification matrix method(SMM) is proposed to eliminate the constraint equations among SLEs in the frame of ANCF.With this method,the inner and the boundary nodal coordinates of element characteristic matrices can be separated simply and efficiently,especially on condition that there are vast nodal coordinates.So the element characteristic matrices can be added end to end circularly.Thus,the dynamic model of deployable structure reduces dimension and can be assembled without any constraint equation.Next,a new iteration procedure for the generalized-a algorithm is presented to solve the ordinary differential equations(ODEs) of deployable structure.Finally,the proposed methodology is used to analyze the flexible multi-body dynamics of a planar linear array deployable structure based on three scissor-like elements.The simulation results show that flexibility has a significant influence on the deployment motion of the deployable structure.The proposed methodology indeed reduce the difficulty of solving and the amount of equations by eliminating redundant degrees of freedom and the constraint equations in scissor-like elements and among scissor-like elements.     

计及二阶效应的大位移柔性梁杆系统动力学分析

结合小变形条件下梁杆单元精确有限元方法和大位移随动坐标法,建立了计及二阶效应的大位移运动柔性梁单元的动力学方程.首先从小变形结构入手,建立考虑二阶效应的柔性梁压弯力学模型,推导出二阶理论条件下平面压弯梁的精确有限元方程,进而获取二阶理论条件下梁单元精确刚度阵.运用大位移随动坐标法建立大位移几何非线性弹性梁杆单元平衡方程,使用柔性多体动力学的相对描述方法推导大位移梁单元在局部坐标系下的动力学方程.通过结点位移、速度和加速度在随动坐标系与整体坐标系间的相互关系得到梁单元在整体坐标系下的包含二阶效应的动力学方程.对某型港口起重机臂架系统的变幅工况进行了计及二阶效应的弹性动力分析.     

Numerical simulation of fluid-structure interaction of a moving flexible foil

The hybrid Cartesian/immersed boundary method is applied to fluid-structure interaction of a moving flexible foil. A new algorithm is suggested to classify immersed boundary nodes based on edges crossing a boundary. Velocity vectors are reconstructed at the immersed boundary nodes by using the interpolation along a local normal line to the boundary. For eliminating pressure reconstruction, the hybrid staggered/non-staggered grid method is adapted. The deformation of an elastic body is modeled based on dynamic thin-plate theory. To validate the developed code first, free rotation of a foil in a channel flow is simulated and the computed angular motion is compared with other computational results. The code is then applied to the fluid-structure interaction of a moving flexible foil which undergoes large deformation due to the fluid loading caused by horizontal sinusoidal motion. It has been shown that the moving flexible foil can generate much larger vertical force than the corresponding rigid foil and the vertical force can be attributed to the downward fluid jet due to the alternating tail deflection. This paper was recommended for publication in revised form by Associate Editor Haecheon Choi Sangmook Shin received his B.S. and M.S. degrees in Naval Architecture from Seoul National University, Korea in 1989 and 1991, respectively. He received his Ph.D. degree in Aerospace Engineering from Virginia Tech, USA in 2001. He is currently an Assistant Professor at Department of Naval Architecture and Marine Systems Engineering at Pukyong National University in Busan, Korea. His research interests include fluid-structure interaction, unstructured grid method, internal wave, and two-phase flow. Hyoung Tae Kim received the B.S. and M.S. degrees in Naval Architecture from Seoul National University in 1979 and 1981, respectively and the Ph.D. degree in Mechanical Engineering from University of Iowa, U.S.A. in 1989. Dr. Kim is currently a Professor at the Department of Naval Architecture & Ocean Engineering at Chungnam National University, Korea. His research interests are in the area of Ship Hydrodynamics, CFD calculations of turbulent flows around ships and propellers, and human-powered and solar boat design.     

滚动轴承刚柔多体接触动力学分析

以柔性多体动力学理论为基础,提出了以相对坐标描述刚柔多体接触滚动轴承的递推数值分析方法。以球轴承为例,研究了滚动轴承刚柔多体接触输出响应的动态特性。综合考虑滚动体与轴承内外圈滚道的时变接触刚度、柔性接触、摩擦、离心力等非线性因素,分析出转速、摩擦力和预紧力对滚动轴承的时变接触力和时变振动位移的影响。结果表明,以相对坐标描述刚柔多体接触滚动轴承的动力学模型,可以有效地解决滚动体与滚道间的时变接触振动响应和柔性接触等非线性接触动力学问题。     

大位移、变拓扑空间机构的动力分析

给出了一种大位移、变拓扑空间机构的动力分析方法。由物体相对坐标和有限元节点坐标描述系统的运动与变形，通过运动相容条件确定系统空间构形的连续性和唯一性，建立了变结构、刚柔多体系统动力学方程。并由算例表明了该方法的精度与效率     

Investigation of variations of lubricating oil diluted by post-injected fuel for the regeneration of CDPF and its effects on engine wear

The purpose of the present study was to investigate the effects of oil diluted by post-injected fuel for CDPF regeneration on engine wear and to find out the characteristic variation of diluted oil according to operating conditions. Experimental studies were made on a 2700 cc, 5 cylinder engine with an after-treatment system. Fuel content in oil increased according to the increase in the duration of post injection. A fuel dilution chart was made to predict the existing fuel content in used oil. The oil analysis method using this chart was validated through the comparison of the results analyzed by GC. The oil contamination by the post-injected fuel caused the quantity of blow-by gas and engine wear to increase and main gallery pressure to decrease. This paper was recommended for publication in revised form by Associate Editor Kyoung Doug Min Bong-Ha Song received a B.S. degree in Mechanical Engineering from Konkuk University in 1999. He received a M.S. degree from Yonsei University in 2002. He then went to Ajou University to get a Ph.D degree. Bong-Ha Song is currently a student at the School of Mechanical Engineering at Ajou University in Suwon, Korea. Yun-Ho Choi received a B.S. degree in Mechanical Engineering from Seoul National University in 1978. He then went on to receive his M.S. and Ph.D. degrees from Pennsylvania State University in 1984 and 1988, respectively. Dr. Choi is currently a professor at the Division of Mechanical Engineering at Ajou University in Suwon, Korea. Dr. Choi’s research interests are in the area of Computational Fluid Dynamics, Thermal Propulsion Systems Modeling and Two Phase Flows.     

Applications of fiber models based on discrete element method to string vibration

This study applies DE (discrete element) computational method to the dynamic problems of a vibrating string. The DE method was originally initiated to analyze granular materials and now it has expanded to model fabric dynamics which is of interest in a number of applications including those that manufacture or handle textiles, garments, and composite materials. Owing to the complex interactions between each discrete element, simple circular geometric rigid model has been used in the conventional DE method. However, in order to analyze the slender shape and flexibility of materials such as fabrics or strings, longer and flexible geometric models, named as fiber models, was developed. The fiber model treats a series of connected circular particles, and further can be classified as being either a RF (rigid fiber) or a CFF (completely flexible fiber) model. To check the feasibility of those models, dynamic problems were solved and it is found that the fiber models accurately simulate the dynamic and vibration behaviors of horizontally or vertically placed strings. This paper was recommended for publication in revised form by Associate Editor Hong Hee Yoo Junyoung Park received B.S. and M.S degrees in Mechanical Engineering from Kyungpook National University in 1996 and 1998, respectively. He then went on to receive his Ph.D. degree from Purdue University in 2003. Dr. Park is currently an assistant professor at the School of Mechanical Engineering at Kumoh National Institute of Technology in Gumi, Korea. Dr. Park’s research interests are in the area of nano technology, particle technology, and analysis of pedestrian flow. Namcheol Kang received B.S. and M.S degrees in Mechanical Engineering from KAIST and Seoul National University in 1992 and 1994, respectively. He then went on to receive his Ph.D. degree from Purdue University in 2004. Dr. Kang is currently an assistant professor at the School of Mechanical Engineering at Kyungpook National University in Daegu, Korea. Dr. Kang’s research interests are in the area of dynamics, vibration and stability of a multiscale mechanical system.     

Fatigue life prediction of a cable harness in an industrial robot using dynamic simulation

The cable which transfers the signal and power in an industrial robot has a problem of fatigue fracture like steel components. Since the cable is very flexible compared to other components of the system, it is difficult to estimate its motion numerically. Some studies have been done on a large deformation problem, especially in a cable, and a few attempts have been made to apply the absolute nodal coordinate formulation (ANCF), which can simulate a large deformation. Only researches about the fatigue life of structural cables or comparative studies of FEM and ANCF simulations can be found. This paper presents a method to simulate the behavior of the cable harness using the ANCF and to predict the fatigue life while computing the strain time history of the point of interest. Rigid body dynamics is applied for the robot system, while ANCF is used for the cable harness. The simulation is performed by using the dynamic analysis process. The material property of the cable is obtained by a test. A simplified model is prepared. With these data, the behavior of the cable is simulated and the fatigue life is predicted.     

Dynamic analysis of a PDP exhaust hole processing equipment considering glass substrate interaction

Exhaust hole drilling is one of the PDP (Plasma Display Panel) manufacturing processes to make about 1mm diameter holes for sucking out air in order to generate vacuum between two PDP glass substrates. In the drilling process, bigsized glasses about the size of a queen size bed are loaded, aligned, drilled, and unloaded, during which the dynamic interactions between glass and the handling equipment are very significant. To analyze exhaust hole drilling equipment dynamics, interaction with glass substrates that have somewhat different material properties from general glasses should be considered. The Young’s modulus and Poisson ratios of the substrates have been determined experimentally and verified via computation that simulates a well-known three-point bending test. Dynamic interaction of the glass with the handling equipment is modeled using a flexible glass and rigid body handling equipment models. The velocity profile by which the glasses are driven and the material properties of the handling equipment components contacting with the glasses are evaluated in view of the structural integrity of the glass and the operational efficiency of the equipment. The dynamic model is demonstrated to be an effective design tool for an exhaust hole drilling machine. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Tae Oh Tak received his B.S. and M.S degree in Mechanical Design and Production Engineering from the Seoul National University in Korea in 1982 and 1984, respectively. He obtained his Ph.D. degree from the University of Iowa, USA in 1990. He is currently a professor at the Department of Mechanical and Biomedical Engineering at the Kangwon National University in Chuncheon, Korea. His research interests are multibody dynamics and sensitivity analysis.     

Analysis and design study of LCD transfer robot using dynamic simulation and experiment

Recently, the size of raw glass has been greatly increased in the new generation Liquid Crystal Display (LCD) technology. To handle bigger and heavier glasses, it is necessary to develop a large scale LTR (LCD Transfer Robot) to support various complicated LCD fabrication processes. This adjustment will result in difficult design problems such as vibration, handling accuracy deterioration, and high stress due to heavier dynamic loads. In turn, these will result in inaccurate transfer motion and fatigue cracks. In this paper, the dynamic simulation technique is introduced to validate a baseline design and to propose new and improved designs for the best performance of heavy-scaled LCD transfer robots. The dynamic models and analysis results were verified by real experiments including strain measure test and motor power test. Using the verified simulation model, some dynamic situations such as the robot’s emergency stop and free fall situation, which were not impossible to test using the real proto robot, were analyzed and predicted using the simulation model. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Jong-Hwi Seo received a B.S. M.S. and Ph.D. degrees from Ajou University in 1998, 2000 and 2005, respectively. He is currently a senior engineer in Mechatronics and Manufacturing Technology Center of Samsung Electronics Co. His research interests are in the area of multibody dynamics, robotics and mechanism design. Jae Chul Hwang received a B.S., M.S., and Ph.D. degrees in mechanical engineering from Seoul National University, Korea, in 1996, 1998, and 2002, respectively. He is currently a senior engineer in Mechatronics and Manufacturing Technology Center of Samsung Electronics Co., Ltd. His research interests are in the area of kinematics and dynamics of serial and parallel kinematic robot. Yong-Won Choi received a M.S degree in Mechanical Engineering from Korea University in 1993. He has worked for Samsung Electronics, Ltd from 1993 and is currently a principle engineer at Robot Mechanism Part in Mechatronics and Manufacturing Technology Center of Samsung Electronics Co. He is interest in the area of robotics, control and mechanism design. Hong Jae Yim received B.S. and M.S degrees in mechanical engineering from Seoul National University, Korea, in 1979, and 1983, respectively. He received Ph.D degree from Univ. of Iowa, USA. He is currently a professor in School of Mechanical & Automotive Engineering, Kookmin University. His research interests are in the area of computer aided kinematics and dynamics of mechanical systems.     

Approximate velocity scale for primary and secondary dual-inlet side-dump flows

Effects of the bulk inlet velocity on the characteristics of dual-inlet side-dump flows are numerically investigated. Non-reacting subsonic turbulent flow is solved by a preconditioned Reynolds-averaged Navier-Stokes equation system with low-Reynolds number k − ɛ turbulence model. The numerical method is properly validated with measured velocity distributions in the head dome and the combustor. With substantial increase in the bulk inlet velocity, general profiles of essential primary and secondary flows normalized by the bulk inlet velocity are quantitatively invariant to the changes in the bulk inlet velocity. This paper was recommended for publication in revised form by Associate Editor Do Hyung Lee Seung-chai Jung received his B.S. degree in Mechanical Engineering from Yonsei University, Korea, in 2001. He then received his M.S. degree in Mechanical Engineering from Yonsei University, Korea, in 2005. Mr. Jung is currently a Ph. D. candidate at Yonsei University, where he is majoring in Mechanical Engineering. Mr. Jung’s research interests include propulsion system and particle-surface collision dynamics. Byung-Hoon Park received his B.S. degree in Mechanical Design and Production Engineering from Yonsei University in 2003. He is currently a Ph.D. candidate in Yonsei University in Seoul, Korea. His research interests include performance design of propulsion systems and nu-merical analysis of instability in multiphase turbulent reacting flow-fields. Hyun Ko received his B.S. degree in Aerospace Engineering from Chonbuk National University, Korea, in 1996. He then received his M.S. degree in Mechanical Design from Chonbuk National University, Korea, in 1998. In 2005, he obtained his Ph.D. degree from Yonsei University, where he majored in mechanical engineering. Dr. Ko is currently a Principal Research Engineer of the MicroFriend Co., Ltd. in Seoul, Korea. His research interests include propulsion related systems and computational fluid dynamics. Woong-sup Yoon received his B.S. degree in Mechanical Engineering from Yonsei University, Korea, in 1985. He then received his M.S. degree from University of Missouri-Rolla in 1989. In 1992, he obtained his Ph.D. degree from the University of Alabama in Huntsville, where he majored in mechanical and aerospace engineering. Dr. Yoon is currently a professor at the School of Mechanical Engineering at Yonsei University in Seoul, Korea. His research interests include propulsion system and particle-related environmental/ thermal engineering.     

Optimal operating points of PEM fuel cell model with RSM

The output power efficiency of the fuel cell system mainly depends on the required current, stack temperature, air excess ratio, hydrogen excess ratio, and inlet air humidity. Therefore, the operating conditions should be optimized to get maximum output power efficiency. In this paper, a dynamic model for the fuel cell stack was developed, which is comprised of a mass flow model, a gas diffusion layer model, a membrane hydration, and a stack voltage model. Experiments have been performed to calibrate the dynamic Polymer Electrolyte Membrane Fuel Cell (PEMFC) stack model. To achieve the maximum output power and the minimum use of hydrogen in a certain power condition, optimization was carried out using Response Surface Methodology (RSM) based on the proposed PEMFC stack model. Using the developed method, optimal operating conditions can be effectively selected in order to obtain minimum hydrogen consumption. This paper was recommended for publication in revised form by Associate Editor Tong Seop Kim Dong-Ji Xuan received his B.S. degree in Mechanical Engineering from Harbin Engineering University, China in 2000. He then received his M.S. degree in Mechanical Engineering from Chonnam National University, South Korea in 2006. Currently, he is a Ph.D. candidate of the Department of Mechanical Engineering, Chonnam National University, South Korea. His research interests include control and optimization of PEM fuel cell system, dynamics and control, and mechatronics. Zhen-Zhe Li received his B.S. degree in Mechanical Engineering from Yanbian University, China in 2002. He then received his M.S. degree in Aerospace Engineering from Konkuk University, South Korea in 2005 and his Ph.D. degree in Mechanical Engineering from Chonnam National University, South Korea in 2009. Dr. Li is currently a Researcher of the Department of Mechanical Engineering in Chonnam National University, South Korea. Dr. Li’s research interests include applied heat transfer, fluid mechanics, and optimal design of thermal and fluid systems. Jin-Wan Kim received his B.S. degree in Aerospace Engineering from Chosun University, South Korea in 1990. He then received his M.S. degree in Aerospace and Mechanical Engineering from Korea Aerospace University, South Korea in 2003 and his Ph.D degree in Mechanical Engineering from Chonnam National University, South Korea in 2008. He is currently a Post Doctor of the Department of Mechanical Engineering in Chonnam National University, South Korea. His research interests include control of hydraulic systems, dynamics and control, and mechatronics. Young-Bae Kim received his B.S. degree in Mechanical Design from Seoul National University, South Korea in 1980. He then received his M.S. degree in Mechanical Engineering from the Korean Advanced Institute of Science and Technology (KAIST), South Korea in 1982 and his Ph.D. degree in Mechanical Engineering from Texas A&M University, USA in 1990. Dr. Kim is currently a Professor of the School of Mechanical and Systems Engineering in Chonnam National University, South Korea. Dr. Kim’s research interests include mechatronics, dynamics and control, and fuel cell hybrid electric vehicle (FCHEV) systems.