Automatic tool changers(ATCs) store tools used in a machining center to its magazine and changes the tools automatically. Tools of machine centers are changed and then precisely equipped to spindle system by the ATC. Therefore, the stability and reliability of the ATC is very important. But, there is lack of development and evaluation on basic performance and vibration of the ATCs. So, in this study, a BT40 ATC test bench was developed to verify stability and reliability of BT40 ATCs.

Reliable results can’t be derived without the notion of measurement uncertainty. The reason is that the measured value includes a lot of uncertain factors. Finding the factor that affect the measurement of parameter is important for estimation of measurement uncertainty. In this paper, the evaluation of uncertainty analysis about positioning accuracy measurements of high precision feed mechanism is presented to evaluate the important factors of uncertainty.

Recently, a high speed spindle is an essential part of machine tools to satisfy latest demand of high precision product and machining of hard materials. But, there are many disadvantages such as heat generation of built-in-motor, bearing friction, noise, vibration and displacement because of the high speed. Many researches on spindle systems have been conducted for solving these problems. In this study, technical trend of machine tools spindle systems are analyzed with patent PSM, mapping and grouping. The analysis is carried out for the applied patent during January 2000 and December 2009 in Korea, Japan, EU and U.S.A. And development of the direction, strategy and promising technologies of the spindle system are suggested.

Laser assisted machining is the processing method that preheating brittle materials by laser heat source and cutting the soften area. This processing applied to various industries because it can be cutting difficult-to-cut materials. However, the laser assisted machining appeared the limitations of processing for equipped with the spindle. So, it assumed separate model that spindle and laser assisted machining. In feed, the calculation of changing the angle of the laser module according to preheat point and the shape of the feed is important and it tried easy calculating changing angle of 1-axis Manipulator in separate model. In 3 types feed shape, angle of 1-axis Manipulator was calculated when fixed and moved in the outside of spindle. In this study, suggest 2 types of methods for laser module when fixed and moved.

Feed drive systems are used to position the machine tool components carrying the cutting tool and workpiece to the desired location. Hence, their positioning accuracy and speed determine the quality and productivity of machine tools. In this paper, technical trend of machine tools feed drive systems are analyzed by patent mapping. And this paper suggested future development direction of feed drive systems. The analysis is carried out by using problem solution map (PSM) for the applied patent during January 2000 and December 2009 in Korea, Japan, EU and U.S.A.

Stroke patients should exercise for the rehabilitation of their fingers, because they can’t use their hand and fingers. The moving direction of thumb of five fingers is different that of four fingers (force finger, middle finger, ring finger, little finger). The thumb rehabilitation robot for rehabilitation exercise must be included a force control system, because robot can injure thumb by applying too much force. In this paper, the rectangular-type thumb rehabilitation robot was developed for stroke patient’s thumb rehabilitation exercise of the flexibility rehabilitation exercise. The characteristic test of the developed rectangular-type thumb rehabilitation robot was carried out with normal men in their twenties. As a result, it is thought that the robot can be used for the flexibility rehabilitation exercise of stroke patient’s thumb.

In this study, it is performed that the assessment of feasibility of developed material processing facilities using tele-operation manipulator system for the pyroprocessing. To evaluate the performance of developed facilities using tele-operation system, several performance indices are considered as remote visibility, remote reachability and remote manipulability. These are applied to RHEM (Remote Handling Evaluation Mock-up) and digital mock-up system respectively. Through this approaches, several requirements for the system improvement are deduced and preliminary inspection for real system application is fully performed. Additionally, assembly and disassembly tasks for the repair of remote handling system are also examined remotely in RHEM and evaluated those performances.

Fretting fatigue tests were conducted to investigate the effect of contact pressure on fretting fatigue behavior in aluminum alloy A7075-T6. Test results showed that when the contact pressure is so low that gross or partial slip occurs at the pad/specimen interface, fretting fatigue damage increases with the contact pressure. However, when the contact pressure is high enough to prevent slip at the interface, fretting fatigue damage decreases with the contact pressure. In order to understand how the contact pressure influence the fretting fatigue damage, finite element analyses were conducted and the analysis results were used to evaluate critical plane fretting fatigue damage parameters and their components. It is revealed that fretting fatigue damage estimated with the parameters exhibits the same variation as that in the tests. Moreover, the variation of fretting fatigue damage is closely related with that of the maximum normal stress on the critical plane rather than the strain amplitude on the critical plane.

In this paper, design optimization of C-frame of a precision drilling and autorivet machine has been performed. The machine, Autoriveter has been developed by Korea Aerospace Industry (KAI), For current autoriveter, it is hard to achieve high efficiency because of heavy weight of the machine. In this paper, we suggest new structure of the current C-frame, a part of autoriveter, by optimization. The result of the study can give much profit for mass-production of the machine.

A Gimbal structure system in observation reconnaissance aircraft is made up of camera module and stabilization drive device supporting camera module. During flight for image recording, the aircraft undergoes serious accelerations with wide frequencies due to several factors. Though base excitation of stabilization drive device induces vibration of camera module, it must get the stable and clean images. To achieve this aim, acceleration of camera module must be reduced. Hence, vibration isolators were installed to stabilization drive device. Considering isolators and bearings in the stabilization drive device, vibration characteristics of gimbal structure system were analyzed by finite element method. For three translational direction, acceleration transmissibility of camera module was calculated by harmonic responses analysis in the frequency range of 5 ~ 500 Hz. In addition to, sine-sweep experiment were performed to prove correctness of present analysis.

Processing of Scanning electron microscope imaging has been analyzed in both secondary electron (SE) imaging and backscattered electron (BSE) image. Because of unique characteristics of both secondary electron and backscattered electron image, mechanism of imaging process and image quality are quite different each other. For the sake of characterize imaging process, Monte Carlo simulation code have been developed. It simulates electron penetration and depth profile in certain material. In addition, secondary electron and backscattered electron generation process as well as their spatial distribution and energy characteristics can be simulated. Geometries that has fundamental feature have been imaged using the developed Monte Carlo code. Two, SE and BSE images generation process will be discussed. BSE imaging process can be readily used to discriminate in both material and geometry by simply changing position and direction of BSE detector. The developed MC code could be useful to design BSE detector and their position. Furthermore, surface reconstruction technique is possibly developed at the further research efforts. Basics of Monte Carlo simulation method will be discussed as well as characteristics of SE and BSE images.

In 3D integration package using TSV technology, bonding is the core technology for stacking and interconnecting the chips or wafers. During bonding process, however, warpage and high stress are introduced, and will lead to the misalignment problem between two chips being bonded and failure of the chips. In this paper, a finite element approach is used to predict the warpages and stresses during the bonding process. In particular, in-plane deformation which directly affects the bonding misalignment is closely analyzed. Three types of bonding technology, which are Sn-Ag solder bonding, Cu-Cu direct bonding and SiO2 direct bonding, are compared. Numerical analysis indicates that warpage and stress are accumulated and become larger for each bonding step. Inplane deformation is much larger than out-of-plane deformation during bonding process. Cu-Cu bonding shows the largest warpage, while SiO2 direct bonding shows the smallest warpage. For stress, Sn-Ag solder bonding shows the largest stress, while Cu-Cu bonding shows the smallest. The stress is mainly concentrated at the interface between the via hole and silicon chip or via hole and bonding area. Misalignment induced during Cu-Cu and Sn-Ag solder bonding is equal to or larger than the size of via diameter, therefore should be reduced by lowering bonding temperature and proper selection of package materials.

Recently porous polymer has widely been applied to packaging, heat isolation, and sound absorption in various fields from the electrics to the automobiles industry. A lot of micro porosities inside foamed polymer provide lower heat conduction and lighter weight than non-porous polymer, because they involve gas or air during foaming process. In this paper experimental approaches of the UV laser micro machining behavior for Expanded Polypropylene (EPP) foamed polymer materials, which have different expansion rates, were investigated. From these results, the ablation phenomena were finally observed that the ablation is depended upon stronger photochemical than photo-thermal effect. This study will also help us to understand interaction between UV laser beam and porous polymer.

The pharmacological therapies and whole body vibration as non-pharmacological therapies were known to have adverse side effects. Therefore, partial stimulation was suggested and its effects were evaluated. This study aimed to evaluate the site-specific effects of partial stimulator for treatment of osteoporosis induced by estrogen deficiency. Sixteen virginal Sprague-Dawley rats (12 weeks old) were divided into 2 groups(no stimulation, stimulation groups). All rats were ovariectomised to induce osteoporosis. After 3 weeks of operation, the right tibiae in rats of stimulation group (frequency: 10Hz, cycle: 1500, strain on bone surface: 2000με) were stimulated perpendicularly at right tibia by using partial stimulator for 6 weeks (3days/week). The right tibiae in rats were scanned, before stimulation (0 week) and at 6 weeks after stimulation by using invivo micro computed tomography. For investigation of changes in morphological characteristics, structural parameters were measured and calculated. At 6 weeks the morphological characteristics (relative value) in stimulation group were significantly enhanced than those in no stimulation group (p<0.05). In this study, we find that after 6 weeks of partial stimulation, the morphological characteristics of tibia trabecular bone were enhanced. Thus, we concluded that partial stimulation could be used to treat osteoporosis.

The structural and functional disorder of a detrusor induces a bladder hypertrophy and degenerates a bladder muscle gradually by preventing normal urination. Thus, the thickness of the bladder wall has been increased in proportion to the degree of bladder outlet obstruction. In this study, the mechanical characteristics of the detrusor is analyzed for the physical properties and the thickness changes of the bladder muscle using a mathematically analytic method. In order to obtain the mechanical property of the bladder muscle, the tensile test of porcine bladder tissue is performed because its property is similar to that of human. The result of tensile test is applied to the mathematically model as Mooney Rivlin coefficients which represent the hyperelastic material. The model of the bladder is defined as the spherical shape with the initial volume of 50ml. The principal stress and strain according to the thickness are analyzed. Also, computer simulations for three types of the material property for the model of the bladder are performed based on the fact that the stiffness of the bladder is weakened as the progress of the benign prostatic hyperplasia. As a result, the principal stress is 341kPa at the initial thickness of 2.2mm, and is 249kPa at 6.5mm. As the bladder wall thickness increases, the principal stress decreases. The principal stress and strain decrease as the stiffness of the bladder decreases under the same thinkness.