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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Transactions of the Korean Society of Mechanical Engineers A
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Journal DOI :
The Korean Society of Mechanical Engineers
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Volume & Issues
Volume 34, Issue 12 - Dec 2010
Volume 34, Issue 11 - Nov 2010
Volume 34, Issue 10 - Oct 2010
Volume 34, Issue 9 - Sep 2010
Volume 34, Issue 8 - Aug 2010
Volume 34, Issue 7 - Jul 2010
Volume 34, Issue 6 - Jun 2010
Volume 34, Issue 5 - May 2010
Volume 34, Issue 4 - Apr 2010
Volume 34, Issue 3 - Mar 2010
Volume 34, Issue 2 - Feb 2010
Volume 34, Issue 1 - Jan 2010
Selecting the target year
A Collaboration Method to Confine a Robot with Multiple Robots
Choi, Jun-Yong ; Kim, Dong-Hwan ; Lee, Gui-Hyung ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 953~964
DOI : 10.3795/KSME-A.2010.34.8.953
In this study, we proposed duty executions to confine a robot in a specific place with multiple robots. The proposed method involved the use of a role classifier for assigning labor roles, behavior selector for each robot, and a collaboration manager for handling complex situations. Further, we verified the validity of the proposed method by performing simulations to confine a robot in the specific location by using multiple robots.
Structure Optimization of a Nut for Prevention of Bolt Loosening
Cheong, Kwang-Yeil ; Park, Tae-Won ; Jung, Sung-Pil ; Chung, Won-Sun ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 965~970
DOI : 10.3795/KSME-A.2010.34.8.965
Bolts and nuts are widely used to fasten mechanical parts together in machines and structures. The primary role of a nut is to maintain the axial force of a bolt. In this paper, a new type of a lock nut that uses a spring is studied. To have a spring within a nut, a cocking process to narrow the top of the nut is adopted, but cracking occurred in the process. In this study, strain of an initial model is measured using the finite element analysis program, MSC/Marc. The occurrence of the crack was studied by comparing the maximum observed strain of a model with the maximum strain indicated by an accurate stress-strain diagram of 1020 steel. Then, the structure of the lock nut was optimized by response surface analysis to prevent cracking. The prototype of the lock nut was manufactured on the basis of the optimization result, and cracking did not occur.
Development of a Navigation Control Algorithm for Mobile Robots Using D
Search and Fuzzy Algorithm
Jung, Yun-Ha ; Park, Hyo-Woon ; Lee, Sang-Jin ; Won, Moon-Cheol ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 971~980
DOI : 10.3795/KSME-A.2010.34.8.971
In this paper, we present a navigation control algorithm for mobile robots that move in environments having static and moving obstacles. The algorithm includes a global and a local path-planning algorithm that uses
search algorithm, a fuzzy logic for determining the immediate level of danger due to collision, and a fuzzy logic for evaluating the required wheel velocities of the mobile robot. To apply the
search algorithm, the two-dimensional space that the robot moves in is decomposed into small rectangular cells. The algorithm is verified by performing simulations using the Python programming language as well as by using the dynamic equations for a two-wheeled mobile robot. The simulation results show that the algorithm can be used to move the robot successfully to reach the goal position, while avoiding moving and unknown static obstacles.
Characterization of Dynamic Deformation Behavior of Al 7075-T6 at High Temperature by Using SHPB Technique
Lee, Ouk-Sub ; Park, Jin-Su ; Choi, Hye-Bin ; Kim, Hong-Min ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 981~987
DOI : 10.3795/KSME-A.2010.34.8.981
The split Hopkinson pressure bar (SHPB) technique is extensively used to characterize material deformation behavior under high strain rate condition. In this study, the dynamic deformation behavior of aluminum 7075-T6 under a high strain rate and at a high temperature is investigated by using a modified SHPB set-up with the pulse shaper technique. The parameters used in the Johnson-Cook constitutive equation are determined by using the SHPB experimental results including the data on the effects of strain rate, temperature, strain hardening, and thermal softening of the material.
Statistical Space-Time Metamodels Based on Multiple Responses Approach for Time-Variant Dynamic Response of Structures
Lee, Jin-Min ; Lee, Tae-Hee ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 989~996
DOI : 10.3795/KSME-A.2010.34.8.989
Statistical regression and/or interpolation models have been used for data analysis and response prediction using the results of the physical experiments and/or computer simulations in structural engineering fields. These models have been employed during the last decade to develop a variety of design methodologies. However, these models only handled responses with respect to space variables such as size and shape of structures and cannot handle time-variant dynamic responses, i.e. response varying with time. In this research, statistical space-time metamodels based on multiple response approach that can handle responses with respect to both space variables and a time variable are proposed. Regression and interpolation models such as the response surface model (RSM) and kriging model were developed for handling time-variant dynamic responses of structural engineering. We evaluate the accuracies of the responses predicted by the two statistical space-time metamodels by comparing them with the responses obtained by the physical experiments and/or computer simulations.
Characteristic of Mechanical Clinching for Al5052 to High-Strength Steels
Lee, Chan-Joo ; Lee, Sang-Kon ; Lee, Seon-Bong ; Kim, Byung-Min ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 997~1006
DOI : 10.3795/KSME-A.2010.34.8.997
For manufacturing modern cars, so-called multi-materials, such as aluminum alloy with high-strength steels, are used. For obtaining such materials, a new joining method is required to achieve the multi-material design. Mechanical clinching is one of joining methods used to join the dissimilar materials. The objective of this study is to investigate the characteristics of mechanical clinching of Al5052 alloy to high-strength steels (SPFC440, 590, 780). Using FE-analysis and clinching experiment, the joinability of Al5052 alloy to high-strength steel is evaluated by geometrical shape of mechanical clinched joint, such as neck-thickness and undercut. Further, the joint strength is evaluated by performing a single-lap shear test. The upper high-strength steel SPFC780 was not clinched because of the necking of the upper sheet. The joint strength increased with increasing strength of the upper sheet. For the lower high-strength steel sheet, the joinability and joint strength decreased with increasing strength of the lower sheet.
Study on the Local Refinement in Spline Finite Element Method by Using Hierarchical B-spline
Hah, Zoo-Hwan ; Kim, Hyun-Jung ; Youn, Sung-Kie ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1007~1013
DOI : 10.3795/KSME-A.2010.34.8.1007
A new local refinement scheme for spline finite element method has been proposed; this scheme involves the use of hierarchical B-spline. NURBS has been widely used in CAD; however, the local refinement of NURBS is difficult due to its tensor-product property. In this study, we attempted to use hierarchical B-splines as local refinement strategy in spline FEM. The regions of high gradients are overlapped by hierarchically-created local meshes. Knot vectors and control points in local meshes are extracted from global meshes, and they are refined using specific schemes. Proper compatibility conditions are imposed between global and local meshes. The effectiveness of the proposed method is verified on the basis of numerical results. Further, it is shown that by using a proposed local refinement scheme, the accuracy of the solution can be improved and it could be higher than that of the solution of a conventional spline FEM with relatively lower degrees of freedom.
A Steel Ball Impact Damage Behavior of RS-SiC Ceramic Materials
Oh, Sang-Yeob ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1015~1021
DOI : 10.3795/KSME-A.2010.34.8.1015
In this study, the effect of the C/SiC composition ratio on the impact damage of a reaction sintered SiC (RS-SiC) plates was evaluated. An impact test was conducted by using an air gun. The impacter used was a steel ball with a diameter of 2 mm, and the impact velocities were 113, 122, and 180 m/s. The RS-SiC plates were
mm with different C/SiC composition ratios. The ring crack diameters damaged by a steel ball were determined using SEM images. It was observed that the maximum diameter increased with increasing impact velocity, and it rapidly changed with increasing C/SiC composition ratio because of the effect of residual Si and the variation flexural strength. Cone cracks were formed in the case of C/SiC composition ratios of 0.4~0.5, this indicated that the impact damage changed from a ring crack to a cone crack in this critical range of C/SiC composition ratios. The C/SiC composition ratio of 0.3 was determined to be the optimal ratio for the RS-SiC manufacturing process.
Design and Optimization of Intelligent Service Robot Suspension System Using Dynamic Model
Choi, Seong-Hoon ; Park, Tae-Won ; Lee, Soo-Ho ; Jung, Sung-Pil ; Jun, Kab-Jin ; Yun, Ji-Won ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1023~1028
DOI : 10.3795/KSME-A.2010.34.8.1023
Recently, an intelligent service robot is being developed for use in guiding and providing information to visitors about the building at public institutions. The intelligent robot has a sensor at the bottom to recognize its location. Four wheels, which are arranged in the form of a lozenge, support the robot. This robot cannot be operated on uneven ground because its driving parts are attached to its main body that contains the important internal components. Continuous impact with the ground can change the precise positions of the components and weaken the connection between each structural part. In this paper, the design of the suspension system for such a robot is described. The dynamic model of the robot is created, and the driving characteristics of the robot with the designed suspension system are simulated. Additionally, the suspension system is optimized to reduce the impact for the robot components.
A Study on the Measurement of Roundness Profile for Rotating Object Using Two Points in Succession Measuring Method
Lee, Min-Ki ; Lee, Eung-Suk ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1029~1034
DOI : 10.3795/KSME-A.2010.34.8.1029
In this paper, we present the roundness profile and run-out error measurement for a rotating shaft. The devices for measuring the roundness require a precision rotation table which is used as a reference to obtain the circular profile. Therefore, the roundness measuring system is expensive and requires precision manufacturing. The two-point method for succession measurement has been used to obtain a linear profile or used in straightness measurement using two displacement measuring devices. In this paper, the method is used for measuring the circular profile of a rotating shaft. A method to remove the vibration of the shaft, i.e., the run-out, is used, and the original circular profile is obtained from the measured raw data that excludes the run-out error of the rotating shaft. This method will be useful for obtaining the precise circular profile without using a precision reference circular artifact.
Boundary Element Analysis for Head-Related Transfer Function in the Case of Korean Adults
Lee, Doo-Ho ; Ahn, Tae-Soo ; Ki, Dong-Hwan ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1035~1044
DOI : 10.3795/KSME-A.2010.34.8.1035
Head-related transfer function (HRTF) is an acoustic transfer function from a sound source to the ear canal entrance position. HRTFs are very important information in the construction of virtual sound fields. HRTFs also vary for different individuals. In this study, characteristics of HRTF for an average Korean are investigated numerically by comparing with the HRTF for a standard Knowles Electronics Manikin for Acoustic Research (KEMAR). A boundary element (BE) model for an adult Korean is developed using the computerized tomography (CT) data in order to investigate the variation in HRTFs for different individuals. The boundary conditions of the BE model are identified by comparing the numerical results with the experimental results. The numerical model shows that accurate HRTFs can be calculated efficiently over full audible frequency range for individuals.
Development of Integrated Design System for Mechanical Rubber Components
Woo, Chang-Su ; Kim, Wan-Doo ; Kim, Young-Gil ; Shin, Wae-Gi ; Lee, Seong-Hoon ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1045~1050
DOI : 10.3795/KSME-A.2010.34.8.1045
Fatigue analysis and lifetime evaluation are very important in design procedure for assuring the safety and reliability of rubber components for mechanical systems. Till recently, the technology for the design, analysis, and evaluation of rubber products was required to manufacture rubber products with high quality, fidelity, and reliability. However, in the rubber-manufacturing companies in Korea, the processes of compound mixing, manufacturing of rubber products, and improvement of rubber properties are based on the trial-and-error method and experience. The objectives of this study are to establish methods for testing rubber materials, to develop a database of the properties of rubber materials, to evaluate the performance of rubber components, and to develop a system for predicting fatigue life. A method to predict fatigue-life of rubber components was proposed; in this method, the finite-element analysis and fatigue damage parameter as determined from a fatigue test are incorporated.
Combination of Different Numerical Methods for Efficient Thermal Stress Analysis of Casting Process
Kwak, Si-Young ; Lim, Chae-Ho ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1051~1057
DOI : 10.3795/KSME-A.2010.34.8.1051
This paper proposes a method that involves a combination of FDM and FEM for analyzing casting process. At present, many numerical analysis methods such as FDM, FEM, and BEM are used for solving engineering problems. For a given problem, a specific method that is suited to the problem is adopted; in general, FDM or FVM is favored for problems related to fluid flow or heat transfer, and FEM is adopted in stress analysis. However, there is an increasing need for using a combined method for complex and coupled phenomena analysis. Hence, we proposed a method in which FDM and FEM are coupled in three-dimensional space, and we applied this method to analyze casting process. In the proposed method, solidification and heat transfer was analyzed by using FDM. The field data such as temperature distribution were converted into a format suitable for FEM analysis that was used for calculating thermal stress distribution. Using the proposed method, we efficiently analyzed the analysis process from the viewpoints of work and time.
Prediction of Hydraulic Performance of a Scaled-Down Model of SMART Reactor Coolant Pump
Kwon, Sun-Guk ; Park, Jin-Seok ; Yu, Je-Yong ; Lee, Won-Jae ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1059~1065
DOI : 10.3795/KSME-A.2010.34.8.1059
An analysis was conducted to predict the hydraulic performance of a reactor coolant pump (RCP) of SMART at the off-design as well as design points. In order to reduce the analysis time efficiently, a single passage containing an impeller and a diffuser was considered as the computational domain. A stage scheme was used to perform a circumferential averaging of the flux on the impeller-diffuser interface. The pressure difference between the inlet and outlet of the pump was determined and was used to compute the head, efficiency, and break horse power (BHP) of a scaled-down model under conditions of steady-state incompressible flow. The predicted curves of the hydraulic performance of an RCP were similar to the typical characteristic curves of a conventional mixed-flow pump. The complex internal fluid flow of a pump, including the internal recirculation loss due to reverse flow, was observed at a low flow rate.
Static Fluid-Structure Coupled Analysis of Low-Pressure Final-Stage Turbine Blade
Kwon, Sun-Guk ; Lee, Young-Shin ; Bae, Yong-Chae ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1067~1074
DOI : 10.3795/KSME-A.2010.34.8.1067
In this study, a loosely coupled fluid-structure interaction (FSI) analysis was conducted for a low-pressure (LP) final-stage rotor blade. Preliminary FSI analyses of a
sweptback wing and a NASA Rotor 37 compressor blade were performed for verifying the boundary conditions. The results were compared with the established literatures for each model. The FSI analysis of the
sweptback wing was carried out under both stable and unstable conditions. The excessive deformation of the wing was observed within 0.05 s under the unstable condition which is higher than the divergence speed of a wing compared with the stable condition. On the basis of the results of a steady-state study, an unsteady state FSI analysis was conducted for a NASA Rotor 37. Different deformations were observed at trailing edge of the blade in the static FSI and dynamic FSI analysis. A 3D FE model of a LP rotor was generated from the span-wise section data. In order to develop a reasonable model, an impact test was performed and compared to the FE model. Using this FE model, the steady-state FSI analysis was performed successfully.
Bulk Shear-Wave Transduction Experiments Using Magnetostrictive Transducers with a Thin Fe-Co Alloy Patch
Park, Jae-Ha ; Cho, Seung-Hyun ; Ahn, Bong-Young ; Kwon, Hyu-Sang ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1075~1081
DOI : 10.3795/KSME-A.2010.34.8.1075
Recently, the results of many studies have clarified the successful performance of magnetostrictive transducers in which a ferromagnetic patch is used for the transduction of guided shear waves; this is because a thin ferromagnetic patch with strong magnetostriction is very useful for generating and detecting shear wave. This investigation deals with bulk shear wave transduction by means of magnetostriction; on the other hand, the existing studies have been focused on guided shear waves. A modular transducer was developed; this transducer comprised a coil, magnets, and a thin ferromagnetic patch that was made of Fe-Co alloy. Some experiments were conducted to verify the performance of the developed transducer. Radiation directivity pattern of the developed transducer was obtained, and a test to detect the damage on a side drill hole of a steel block specimen was carried out. From the results of these tests, the good performance of the transducer for nondestructive testing was verified on the basis of the signal-to-noise ratio and narrow beam directivity.
Analyses of Behaviors of a Shape-Memory-Alloy Torque Tube Actuator
Kim, Jun-Hyoung ; Kim, Cheol ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1083~1089
DOI : 10.3795/KSME-A.2010.34.8.1083
Shape memory alloys (SMAs) are smart materials. The unique characteristics of SMAs enable the production of large force and displacement. Hence, SMAs can be used in many applications such as in actuators and active structural acoustic controllers; the SMAs can also be used for dynamic tuning and shape control. A SMA torque tube actuator consisting of SMA tubes and superelastic springs is proposed, and the behaviors of the actuator are investigated. From the results of heat transfer analysis, it is proved that the SMA torque tube actuator with both resistive heating of SMA itself and a separate conventional heating rod in the tube core has good performance. The behavior of an actuator system was analyzed by performing a contact analysis, and the twisting motion was noticed when checking the actuation. 3D SMA nonlinear constitutive equations were formulated numerically and implemented by performing a nonlinear analysis by using Abaqus UMAT.
Deriving Reference Data for Alarm System in a Container Crane by Fluid-Structure Interaction Analysis
Han, Dong-Seop ; Han, Geun-Jo ; Kwak, Ki-Suk ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1091~1096
DOI : 10.3795/KSME-A.2010.34.8.1091
This study was conducted to provide reference data for designing an alarm system that can help prevent the overturning of a container crane under wind load. Two methods, namely, fluid-structure interaction (FSI) analysis and windtunnel test, were adopted in this investigation. To evaluate the effect of wind load on the stability of the crane, a 50-ton-class container crane that is widely used in container terminals was adopted as the analysis model and 19 values were considered as design parameters for wind direction. First, the wind-tunnel test for the reduced-scale container crane model was performed according to the wind direction by using an Eiffel type atmospheric boundary-layer wind tunnel. Next, the FSI analysis for the real-scale container crane was conducted using ANSYS and CFX. Then, the uplift force determined from the FSI analysis was compared with that determined from the wind-tunnel test. Finally, a formula to compensate for the difference between the results of the FSI analysis and the wind-tunnel test was proposed.
Two-Stage Design Optimization of an Automotive Fog Blank Cover for Enhancing Its Injection Molding Quality
Park, Chang-Hyun ; Ahn, Hee-Jae ; Choi, Dong-Hoon ; Pyo, Byung-Gi ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1097~1103
DOI : 10.3795/KSME-A.2010.34.8.1097
Injection pressure, an important factor in the filling procedure, should be minimized to enhance injection molding quality. In addition, warping deformation and weld lines, which are representative failures, should be avoided to enhance injection molding quality. To improve injection molding quality, the design procedure for an automotive fog blank cover is divided into two stages. In the first stage, we optimally obtain injection molding process variables that minimize injection pressure and warping deformation by using design of experiments, approximation and optimization techniques equipped in PIAnO (Process Integration, Automation and Optimization), a commercial PIDO (Process Integration and Design Optimization) tool. Then, we determine the thickness of the automotive fog blank cover that enables us to avoid generating weld lines. The design results we obtain in this study are found far better than those of the initial design, which demonstrates the effectiveness of our design method.
Dynamic Characteristics on the CRDM of SMART Reactor
Lee, Jang-Won ; Cho, Sang-Soon ; Kim, Dong-Ok ; Park, Jin-Seok ; Lee, Won-Jae ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1105~1111
DOI : 10.3795/KSME-A.2010.34.8.1105
The Korea Atomic Energy Research Institutes has been developing the SMART (System integrated Modular Advanced ReacTor), an environment-friendly nuclear reactor for the generation of electricity and to perform desalination. SMART reactors can be exposed to various external and internal loads caused by seismic and coolant flows. The CRDM(control rod drive mechanism), one of structures of the SMART, is a component which is adjusting inserting amount of a control rod, controlling output of reactor power and in an emergency situation, inserting a control rod to stop the reactor. The purpose of this research is performing the analysis of dynamic characteristic to ensure safety and integrity of structure of CRDM. This paper presents two FE-models, 3-D solid model and simplified Beam model of the CRDM in the coolant, and then compared the results of the dynamic characteristic about the two FE-models using a commercial Finite Element tool, ABAQUS CAE V6.8 and ANSYS V12. Beam 4 and beam 188 of simplified-model were also compared each other. And simplified model is updated for accuracy compare to 3-D solid.
Designing FMH Impact-Absorbing Structure by Using Subcomponent Collapse Simulation
Kim, Ji-Hun ; Jun, In-Ki ; Choi, Jae-Min ; Kim, Sung-Hun ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1113~1118
DOI : 10.3795/KSME-A.2010.34.8.1113
It is requested that the interior compartment of a passenger vehicle must be satisfied with the FMVSS201U regulation, FMH impact test. It is needed the design methodology to find the appropriate structure about the FMH impact. When designing the impact-absorbing structure for the FMH impact test, it is to be noted that the impact absorber must have different performance considering the stiffness of the vehicle as the impact position and approach angle of FMH. In this study, an efficient design methodology was developed by using subcomponent collapse simulation instead of conducting full-vehicle simulation, thereby reducing the time and resources spent. Further, this unit-model simulation helps optimize the impact absorbing structure.
Multistable Microactuators Functioning on the Basis of Electromagnetic Lorentz Force: Nonlinear Structural and Electrothermal Analyses
Han, Jeong-Sam ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1119~1127
DOI : 10.3795/KSME-A.2010.34.8.1119
In this paper, the design and nonlinear simulation of a multistable electromagnetic microactuator, which provides four stable equilibrium positions within its operating range, have been discussed. Quadstable actuator motion has been made possible by using both X- and Y-directional bistable structures with snapping curved beams. Two pairs of the curved beams are attached to an inner frame in both X- and Y-directions to realize independent bistable behavior in each direction. For the actuation of the actuator at the micrometer scale, an electromagnetic actuation method in which Lorentz force is taken into consideration was used. By using this method, micrometer-stroke quadstability in a plane parallel to a substrate was possible. The feasibility of designing an actuator that can realize quadstable motion by using the electromagnetic actuation method has been thoroughly clarified by performing nonlinear static and dynamic analyses and electrothermal coupled-field analysis of the multistable microactuator.
Vibration Characteristics and Topology Optimization of a Double Damper Lock-Up Clutch in a Torque Converter System
Kim, Kwang-Joong ; Kim, Cheol ;
Transactions of the Korean Society of Mechanical Engineers A, volume 34, issue 8, 2010, Pages 1129~1136
DOI : 10.3795/KSME-A.2010.34.8.1129
Damper springs in a drive-line absorb the impulsive torque generated when a lock-up clutch is connected directly, instead of via a fluid coupling. Design optimization and finite element analysis were performed to improve the shock- and vibration-absorption capacity of the lock-up clutch. For this purpose, a multi-body dynamics model was developed by including the main parts of a vehicle, such as an engine with a clutch, a transmission, drive shafts and wheels, and a whole mass of a vehicle. The spring constants were selected so that resonance of a system could be avoided. Damper springs were optimized on the basis of the spring constants, impulsive torques, compressed angles, spring counts, fatigue constraints, etc. Topology optimization was performed for three plates with the damper springs. The compliance was set up as an objective function, and volume fraction was fixed below 0.3. A new shape for the plates was proposed on the basis of the topology result.