Effect of shot peening on the fatigue limit of high tensile strength steel containing a crack on stress concentration zone was investigated. A pre-crack was introduced, subsequently shot peening was introduced. And the bending fatigue tests were carried out. Obtained results were as followings; (1) the fatigue limit of specimens containing a crack of 0.2 and 0.3mm in depth are improved up to around tow times value. (2) In case of shot-peened specimens with a crack of 0.2 mm in depth, fracture occurred from outside the pre-crack moreover they recovered the fatigue limits up to that of specimens with no crack. (3) A safety crack size of shot-peened specimen could be estimated by calculation of stress intensity factor of pre-crack.

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High-temperature plants, such as nuclear and thermal power plants are used under severe conditions. High temperature plants are susceptible to micro-cracks in its structure. This is because there is the effect of cyclic fatigue and creep fatigue. To prevent serious accidents, including small defects in the structure, we predicted the destruction, we must use safely. In particular, the evaluation of fatigue crack development is important. And, it is desirable to develop a more accurate assessment method. In this study, fatigue tests conducted for SUS304 which is often used in high temperature plant. Then observe the behavior of crack development, we examined the relationship between crack growth rate and the elastic-plastic fracture mechanics parameter, J-integral. In addition, the model plate with central crack, the J-integral analysis was performed by the virtual crack extension method.

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In order to investigate effects of texture and humidity on fatigue properties of Al alloy under ultrasonic loading, fatigue tests were carried out using plain specimens cut out from two kinds of age-hardened Al alloys 2017-T4, extruded and drawn bars, in relative humidity of 25% and 85%. The extruded Al alloy had a marked texture of a (111) plane, but a specified orientation was not observed in the drawn Al alloy. The retardation of a crack growth yielded at the surface length below about 1 mm in low humidity of both alloys. Although the crack growth was accelerated in the early growth process by high humidity, there was no or little influence of humidity on the growth rate of a crack over the above retarded length in both alloys. After the retardation of the crack growth, most of fracture surfaces were covered with many slip planes and voids in the extruded alloy and many flat facets in the drawn one, and striations being a main fracture mechanism under rotating bending fatigue of the conventional frequency were very limited.

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This paper describes a development of ultrasonic monitoring technique applied for through thickness fatigue cracks neighboring fillet weld parts. A combination of transmitted wave measurement and reflected wave measurement was found to be useful in quantitative detection of the fatigue crack.In case of 100mm separation between transmitting probe and receiving probe,our method obtains 40mm as an effective area for the quantitative detection.In other hand, small sized cracks bring about an underestimation of the cracks under small stress.Therefore, it is important for a timing optimization of data acquisition by a synchronization with ship movement.

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Recently, the growing demand for light weight technology has been key issue because reducing CO2 emission has become a global challenge work. Magnesium alloys that are lighter than aluminum alloys have a specific gravity of 1.8, which is 2/3 of aluminum alloys. In recent several years, although production of magnesium has risen dramatically, production of magnesium alloy sheet remains still at a very low level. Utilizing cold roll forming for forming wrought magnesium alloys has the advantage of extending markets of magnesium alloys, also cold roll forming of the magnesium alloys has possibilities to manufacture structure materials such as pipes and V sections, C-channels. In the present study, magnesium alloy AZ31 as well as SPCC (cold rolled steel) have been cold roll formed. A desired shape of the product is a pipe with 14mm diameters. A 3D FEM analysis has been conducted to clalify the forming characteristics of AZ31 wrought magnesium alloy. The details of springback mechanism has been analysed in tames of bending strain.

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This study was aimed for investigating of manufacturing high aluminum content Mg alloys using a horizontal twin roll caster. Recently, weight saving has been key issues for lighter transport equipments asa well as electronic component parts. As aalternative materials to aluminum alloys, developing magnesium alloy with higher strength has been expected. Normally high Aluminum content Mg alloy has poor ductility and is difficult to be rolled because of its high strengthl. However, twin roll casting process is sutable for manufacturing wrought Mg alloys because materials can be cast directly from molten metal. In this study, manufacturing of high aluminum content magnesium alloy sheet using the roll casting process has been carried out. Effects of manufacturing parameter, such as roll velocity, pouring temperature and roll gap, on casting was investigated. A microscopic observation of the crystals of cross section of as cast strip as well as rolled strip was conducted.

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The Zn-2mass%Al alloy installed in a tubular mold of different inner diameters (the specimen diameter) was solidified from the substrate in the temperature gradient. With decreasing specimen diameter, the transition from the planar growth to the columnar growth occurred in the shorter period during furnace cooling. However, when the specimen diameter decreased to 0.1mm, there were two transition periods: the early transition and the delayed transition. It was thought that the smaller specimen diameter restricted the perturbation behavior of the interface to change the stability condition of the interface, and caused the split of the transition period.

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This study leads to some findings from novel formulae for path interval determination and a geometrical analysis of machined surface features in 5-axis milling. Because of space constraint, we only describe the former topic in this paper. In tool path generation, path interval determination is usually performed using the formulae derived from the geometrical relationship between a path interval and a scallop height. However, the formulae have not necessarily been provided for commonly-used cutting tools in every milling. It also seems that there still remains much to be studied on the microscopic topography generated in 5-axis milling. The dual insufficiencies gave authors a clear direction to this study. For path interval determination, the novel expressions for filleted end milling were formulated with the reference to those of other milling tools.

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The automatic welding is widely used for the production of machines and assembly of constructions. It will increase the efficiency of a welding process, productivity and quality of welded joints, if the ability of welding robot and sensors which can monitor the welding process increases. However, there are two problems that the arc welding process is unstable welding and spatters occur in MAG welding and they disturb the vision sensing of welding process. A purpose of this research is construction of a system which is possible to obtain sound welding of joints in the automatic MAG welding. This system monitors the welding area by CCD camera and the images are processed. Then the system detects welding wire and welding line position, and controls the welding robot to realize the automatic seam-tracking. The new image processing algorithm was constructed to eliminate the bad influence of spatters on a welding image and increase the successful percentage of the welding line detection and the welding wire detection.

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The welding control system was used for automatic Tungsten Inert Gas (TIG) welding of horizontally fixed pipe and the effectiveness of this system was experimentally-demonstrated. In this system, a vision sensor for monitoring the molten pool, welding speed controller and neural networking were adopted. The vision sensor consists of a CCD camera and an Omni-directional mirror which is set in the pipe, and captures the inner image of the molten pool during welding process. Then, the optimum welding speed which depends on the width of molten pool was calculated. However, in butt welding of aluminum pipes, melt down often occurs due to arc current inclining to one side of a pipe and high-intensity light of arc current from the butt joint prevents image processing. In order to avoid these problems, a new welding method and an image processing algorithm were developed. Finally, the effectiveness of these systems was experimentally-demonstrated.

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In order to realize the automation of TIG arc welding for thin steel plates, oscillation phenomenon of molten pool was modeled as surface phenomenon of fluid. Based on this oscillation model, the penetration control system was constructed. This system estimates the back bead width using Maruo's formula, and controls the back bead width by PID control. In this system the welding velocity was used as control value. However, welding velocity is an influential factor of the molten pool's shape. Accordingly, if the system uses the welding velocity as control value, it is necessary to monitor the molten pool. Then this system measures natural frequencies and shapes of the molten pool using hybrid sensor system which consists of a vision and an oscillation sensor. It enables the system to estimate and control the back bead width accurately.

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6Al-4V Titanium alloy and 5052 Aluminum alloy sheets were butt welded by using a pulsed YAG laser welding machine. Authers already reported that the joint strength decrease with decreasing plate thickness of fusion zone due to a underfill and burn-through. This report examined that the end of A5052 plate make to L-shape in order to prevent underfill and burn-through. Effect of welding conditions on the pulsed YAG laser on weld ability was investigated concerning the bead appearance, macrostructures, EDX line analysis of fusion zone and mechanical properties.

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TIG welding process is often used to join thin metal plates because of the stability of arc compared with the other arc welding processes. However, the temperature of the tungsten electrode of the TIG welding torch increases and oxidation occurs during welding process. Therefore, the electrode tip is consumed considerably, and the arc stability tends to decrease with welding time. Accordingly, it is important to administrate the electrode tip condition in order to keep the welding process stable. On the contrary, the laser beam has extraordinary stability and directivity because of the nature of the light beam. Therefore, stabilization and control of the unstable TIG arc by the laser beam has been tried. In this study, the control of the arc behavior in welding of thin metal plates using the hybrid welding process combining TIG arc and YAG laser with relatively low power.

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Solid protrusion of 6061 aluminum alloy was formed to SPCC steel sheet by friction welding process, and microstructures and mechanical properties of protrusion were investigated. The protrusion formation was possible in wide range of friction pressure under the rotational speed 750rpm and 1000rpm. The microstructures of welding interface was not observed an intermetallic compound. And it showed fine structure than that of the base metal. The maximum tensile lord of protrusion showed 1300N, and the maximum tensile shear lord of protrusion showed 1600N.

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Recently, die-casting is widely used in many industries. In these cases, molten alloy conditions influence on mechanical properties of final product. We purpose to observe aluminum solidification by ultrasonic measurement. In this study, we reported between relationship temperature and longitudinal wave velocity of aluminum by simulation and experiment. If the temperature of aluminum is raised, wave velocity is down by simulation. We obtain different condition of molten aluminum by inclined cooling plate process. It is difficult to measure process of solidify by ultrasonic in experiment. Therefore, it is measured wave velocity and temperature part of experimental instrument. Aluminum solidification is estimated indirectly.

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Recently, the devices have been progress miniaturization and ultra thin in kinds of fields, especially microelectronic devices and information storage media. Therefore, the measurement of near-surface is very difficult. However, their characteristics are very important in engineering. In this study, influence of phase transformation on mechanical properties of single crystal silicon is investigated.

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The effect of grain boundary microstructure such as grain boundary connectivity and spatial distribution of the grain boundaries on propagation path in sulfur-doped nickel was investigated to reveal the utility of grain boundary engineering for control of fracture resistance to impurity segregation-induced embrittlement in polycrystalline materials. Crack predominantly propagated along high energy random boundaries. Thus, the deflection of crack propagation path strongly depended on the connectivity of random boundaries associated with grain size and shape. Crack propagation rate was found to decrease and branching of cracks occurred when the front of crack reached to low-E coincidence site lattice boundaries.

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Fullerenes are allotropes of carbon with a spherical structure. Fullerene as an additive it is possible to increase the performance of the material. And recently, the devices have been progress miniaturization and ultra thin in kinds of fields, especially microelectronic devices and information storage media. Therefore, the fullerene films are going to be used in the semiconductor. This study investigated the mechanical properties such as hardness and wettability of fullerene films.

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Recently, plastic products are used on various fields because its insulation properties, decorative properties and moldability are better. Generally, plastic products are formed by molding process using die so accuracy of molded is affected by shape of die. This study target examining relationship between deformation of die and molding defect by observing initiation process of molding defect on molding process using visualized die. This paper reported result of observing initiation process of flash and measuring pressure of parting surface of dies and flash size on molding experiment. As a result of experiment, it was came out that flash occur at low pressure region on parting surface, and flash is decrease since enlarging clamping force.

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In performing dynamic fracture experiments of solids, explosives are typically used as energy sources. However, nowadays blasting in urban areas cannot be simply performed. In this study, we conduct laboratory fracture experiments that make use of Q-switch Nd:YAG laser pulses as energy sources. Laser pulses can be handled more safely than explosives. We compare typical crack extension patterns in acrylic sheets that are generated by laser pulses with those produced by ignition of explosives. Both "crush zone" in the vicinity of an energy source and radial cracks, normally observed in blast-generated fractures, can be identified in laser pulse-induced fracture patterns.

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This paper provides characteristics of damage patterns each direction on single crystal silicon wafers by a scratch test. Relationship between normal indent load and scratch force was measured on the major planes of single crystal silicon using scratch test under room temperature condition. Scratching tracks of the surface of single crystal silicon after the scratching tests under very small loading forces were observed. It appears that relationship between normal indent load and scratch force correlates the critical load of damages of silicon. Characteristics of damage pattern on single crystal silicon wafers were clarified based on both scratch curves and observations of the damage patterns.

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New hybrid surface reinforcement consisting of crack healing and low energy electron beam irradiation has been proposed for structural ceramics. Crack healing was found to make surface cracks be innocuous. Low-energy electron beam irradiation was found to significantly harden the treated subsurface layer, which includes the matrix layer near the surface as well as the partly or fully covered silica layer formed by the crack healing. Moreover, it was found not to break the improved fracture strength due to crack healing. And the results suggest that the functionally graded ceramics with large gradient of hardness were successfully fabricated by the hybrid surface reinforcement.

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Short crack fatigue growth was studied using a method of plastic replication on specimens of rail steel that were subjected to fully reversed fatigue loading at ambient temperature. Crack lengths were measured from replicas using an optical microscope from which the growth rate could be calculated. Based on the growth data and adopting the Hobson model, a crack growth equation has been derived in an attempt to describe the physically small crack growth behavior. The equation for the crack growth is presented for the form: (da)/(dN)=Ca_s+D where a_s is the surface length of the crack, N the number of cycles, C the function of the total strain range and D is a constant. By obtaining short crack growth data for different stress levels, a quantitative expression of the equation was obtained.

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The effect of Laves phase embrittlement on the fatigue behavior in type 347 austenitic stainless steel was investigated. When this material is exposed to the temperature range of 700-900℃, the precipitation of the Laves phase occurs, resulting in the embrittlement of the material which is known as the Laves phase embrittlement. Rotary bending fatigue tests have been conducted in laboratory air and in 3%NaCl solution using a niobium-containing austenitic stainless steel, type 347 aged at 700, 800 or 900℃. In laboratory air, the fatigue strengths of 700℃ aged specimens were increased due to the fine Laves phase precipitation in y-phase. Whereas the fatigue strengths of 900℃ aged specimens decreased, which could be attributed to the precipitation of large Laves phases. In 3%NaCl solution, the fatigue strengths of 700℃ aged specimens were lower than those in laboratory air. It is considered that the sensitization took place during the heat treatment, where chromium-depleted zones were formed along grain boundaries.

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Since numerical analyses under elevated temperature usually depend on a constitutive equation of creep, it is necessary to derive a high-precision equation. Creep properties on deformation can be normally obtained using constant load creep machines, but constant stress creep tests are more suitable to acquire high-precision creep data. Conventional uniaxial creep specimens have ridges attached on both sides of gauge length. However, even if the constant stress creep testing machines are used, these ridges prevent area reduction around them, and cause unequal deformation in the gauge part. Authors have proposed cutting slits into the ridge to release the specimen from the circumferential constraint by extensometer ridges. In this study, taking into account a realistic analytic condition, the authors carried out elastic-plastic creep Finite Element (FE) analyses to investigate the performance of uniform deformation. Subsequently, a series of interrupted constant stress creep, tests using SUS304 steel were conducted to examine the effect of introducing slits. The analytical and the experimental results showed that the introduction of these slits into the ridges would affect the deformation during creep, but not improve the uniformity of deformation along the gauge part.

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High chromiun ferritic heat-resistant steels are used for boiler components in ultra-super critical thermal power plants operated over 600℃. In the welded joints of these steels, Type-IV cracks initiate in the fine-grained heat affected zone (FGHAZ) under long-term operations, and cause the degradation of the creep strength. Therefore it is important to predict creep crack growth (CCG) behavior and its fracture life for the safety and reliability assessment of these plants. In this paper, CCG tests were performed at 600℃ employing compact tension (CT) specimens machined from a P91 steel including the weldment. Experimental and analytical test results indicate that creep crack growth rates of P91 weldment could be characterized by C* integral which was independent of test condition.

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The aim of this work is to examine processes of nucleation and development of creep voids under multi-axial stresses. Type-IV creep damage formed in a fine-grained heat effected zone (HAZ) resulted in the degradation of the creep strength of structural components. The stress condition in the fine grained HAZ is usually under multi-axial stress state because the HAZ is bound by the base and the weld metals. In this study, some interrupted creep tests were performed employing circumferentially notched bar specimens of P91 steel to examine the relation between nucleation/development of creep voids and multi-axial stress states. The number of creep voids were counted using SEM photographs. Experimental results showed that creep voids were formed in notch root inclined from the loading axis by about 35 degrees. Elastic creep FE analyses were performed to calculate the change of triaxial factor λ in the notch root during creep. The triaxial factorλand the distribution of voids exhibited the similar trend.

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Nickel-based superalloys are widely used as the heat-resistant materials in various engineering fields. Therefore, it is very important to clarify the viscoelastic properties of these materials because they are often used under elevated temperatures. The final object of this study is to clarify the viscoelastic constitutive relation of Inconel 718 which is one of the most popular nickel-based superalloys. As the preliminary research for this final object, the internal friction (logarithmic decrement) has been measured by the inverted torsion pendulum method with changing the atmospheric temperature. Prior to the measurement, three types of specimens with different grain sizes were prepared by changing the annealing temperature. As the results, it has been clarified that the logarithmic decrement of the large grain size superalloy is smaller than that of the small grain size superalloy and that in some cases, the logarithmic decrement takes a peak value at the atmospheric temperature of approximately 820-850K.

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The amount of the carbon fiber reinforced plastic (CFRJP) increases in the structure use of the civilian passenger aircraft. But the light weight metals are still widely used in the aircraft structure. So the joint of the CFRP and light weight metals are required. Currently, the most major and practical joint method for CFRP and metals is the rivet fastening. Conventional rivet fasteners' materials for the aerospace use are aluminum alloys and titanium alloys. When the CFRP is fastened to the metals by rivets, the galvanic corrosion is of concern, because the CFRP contains the carbon fiber which has the electric conductivity. In this research, to examine the possibility of galvanic corrosion at the CFRP/metal rivet joint, the polarization potential was measured for the pure titanium and the CFRP in the 5wt%NaCl aqueous solution. The polarization potential was recorded for 24 hours. But the current was almost none. The passive layer of the titanium is considered to prevent the corrosion in the NaCl aqueous solution.

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Tetraodontidae have swimming instantaneous force to escape from enemy and can swim for several directions Therefore, their external shapes are thought of as it is better shape for omnidirectional pressure capacity This paper investigates the relation between its eternal shape and compression property by biaxial compression test During the experiments, biaxial loads and loading-axis displacements of six specimens which were cut out of model by moulding were measured In addition, their biaxial strains were obtained by 2D image correlation method As a result, each specimen has particular value of these factors These results are thought to connect to function of part of Tetraodontidae

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Although the epidural anesthesia is essential for less invasive surgery, medical accidents of the epidural puncture happened From former study with the porcine spines, author proposed the reason for the epidural puncture that the ligamentum flavum deform during the epidural needle insertion. In order to check if the human ligamentum flavum deform during the epidural needle insertion actually, Young's modulus of the ligamentum flavum was measured as a fundamental bio-mechanical property. Six porcine spines from a slaughter house were employed. Cross sectional area was measured with an X-ray CT image. Tensile tests toward horizontal and perpendicular direction were done. Stress-strain diagram for 16 specimens exhibited nonlinear slope. Young's modulus was obtained as the slope where the strain was more than 0.5 Averaged Young's modulus was 0.3 MPa for both horizontal and perpendicular directions. Fundamental data could be measured for a finite element analysis.

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The foot joint has the great mechanisms One of the significant parts of this mechanism was arch structure However, the function of it has been remain unclear In this paper, we compared the foot arch structures of normal and flat foot by the photoelasticity method We measured the change of the height We also analyzed the influence of this change on the tendon using 3-dimensional stress freezing method. In first experiment, we compared them using skeletal model, which is known to be a fundamental stress model on the foot joint Next, m order to compare the results by the skeletal model, we made an experiment using reconstructed skeletal muscle and tendon model. According to these experiments, we estimated a stress distribution map of foot This difference between normal and flat foot was decrease m the reconstructed skeletal muscle and tendon model

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In this study, a combination of the three-dimensional finite element method and freezing photoelastic stress analysis was performed on several types of artificial hip stem. Similarly, we analyzed how well fixed As a result, different shape of the stem shows the different stress distribution around the hip jomt in the skeleton, found that there is room for improvement m the shape of the stem material

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Though the badminton can not be called the major sports, they are the sports which hold considerable players population However, m comparison with the tennis racket, the paper which studied the badminton racket is few, and it is not very much studied and has not been announced The research was carried out for the purpose of in this study, it does experimental modal analysis on the badminton racket, and examining the vibration characteristics In this paper, we studied what causes it, the difference of vibration characteristics of the 3 rackets

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Recently, the FRP bats begin to be focused But, FRP bats have a problem with a strong numbness In this paper, the causes of numbness in FRP bats were attempted to be clear by performing experimental model analysis First, the modal parameters of FRP bats were identified with experimental modal analysis Next, to investigate the modal parameter in supporting condition by human's hands, experimental modal analysis was performed Then, the study and its results were shown In the real shot of professional person, questionnaires were done about numbness Next, center of impact were measured and calculated Finally, FEM model was created and calculated

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In the shamisen, Japanese traditional instrument, there is a mechanism to put out the peculiar tone that is called "SAWARI" This mechanism is the feature one in musical instruments in the world However, there are still a lot of uncertain points of the mechanism In this research, it aims to support it to clarify the feature of the shamisen sound, and to emit the shamisen sound assumed to be an ideal As the method, the sound of shamisen is recorded and frequency analysis of "SAWARI" is conducted, and it experiments modal analysis of shamisen's body and skin Further, body's cavernous resonance is recoreded and analyzes using FEM

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This study deals with the movement of ultraviolet (UV) curable resm illuminated at UV ray The movement is observed as particle trajectory patterns obtained using a particle tracking velocimetry technique The specimens consist of glass plates, acrylic plates, vinyl tape and UV curing resin m liquid form with acrylic powder. The specimens are illuminated with UV rays downwards from the upper side of the specimens, and the images of the resin in curing process are captured at a constant time interval using a digital camera Results indicate that the movement of UV curable resin in curing process is affected by the stiffness of the bottom of molds.

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Recently, a new container for liquid of food products, which consists of a case made of a sheet of plastic and a liquid-packing bag with a pouring lip made of a plastic film has been developed The improvement of the resistance of the new container to drop impact is desired because the resistance is not adequately To improve the resistance, it is important to investigate the liquid behavior in liquid-packaging bags In this study, the liquid behavior m liquid-filled plastic film bags with a pouring lip subjected to drop impact is observed using a high speed camera, and the liquid behavior is investigated Results indicated that the bags with a pouring lip have characteristic liquid behavior at the upper part of the bags.

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A method for unwrapping the principal-stress directions from color photoelastic fringes obtained in a semicircular polariscope, which is composed of a plane polariscope with a quarter wave plate, is developed Four phase-shifted photoelastic fringe images are acquired using the polariscope, and used to obtain the wrapped principal-stress direction using a phase-shifting technique. The unwrapping technique is based on a largest region of the correct principal-stress directions, which is obtained using an intersection operation between the extended ranges of the computed principal-stress directions The ability of the method is investigated with computationally simulated color photoelastic fringes of a circular disk and a ring subjected to a concentrated load. Results show that the method is effective for determining the unwrapped

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In this study, the analysis of stress distribution generated to the automobile hub by the cornering force caused when turning had done for discuss optimum structure The experiment used the model of automobile hub made with epoxy resin, the assumption parts of the bearing and brake plate and increased load to the automobile hub by using the assumption parts of the bearing The analysis method was the photoelasticity It was became clear by the analysis that the stress concentration by the cornering force became remarkable at the fillet R neighborhood in the boss root, the bolt hole, and the contact department with the brake plate It is thought that optimum automobile hub can be made by discussing structure of the three points when designing

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A liquid-packaging bag with a simple pouring lip made of flexible plastic film is capable of delaymg the discoloration and decay of liquid food products. It was inferred that this function is due to the prevention of the invasion of air and microorganisms from the pouring lip into the bag. However, the reason air and microorganisms could not enter the bag remains to be determined. In this study, as a fundamental study for discussmg the above reason, the tip of pouring lips after pouring water is observed using a digital camera. Results indicate that the gap thickness of the tip decreases with time after pouring, and become a constant

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The effect of the cross sectional shape of correcting wires on the movement of molars of a lower jaw dentition subjected to distal loads from an implant anchor is investigated usmg a digital image correlation technique A sample consists of a lower jaw, teeth, periodontal membranes, a correcting wire, brackets, and an implant anchor. The circular and rectangular shapes as the cross section of correcting wires are used A force of 5.88 N is applied to the wire near the brackets bonded on the first and second premolars The direction of the force from the horizontal is set to 10°, 20°and 30°.Results indicate that the movement of the molars depends on the cross sectional shape of the wire.

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There are increasing number of adult patients who present at orthodontic clinics. Unlike young patients, many adult patients tend to have lower alveolar height due to the aging and periodontitis. For appropriate orthodontic tooth movement for these patients, it is important to clarify the relationship between the alveolar bone height and the center of resistance in teeth. In the present study, the three-dimensional finite element model which had various alveolar bone height of the maxillary central incisor was created, and the location of the center of resistance was examined. The results showed that the center of resistance sifted to the apical side in the long axis of the incisor according to the decrease in the alveolar bone height.

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Our dual-arm mobile manipulator consists of two manipulators mounted atop a wheeled mobile platform with a stereo camera The original form of the mobile manipulator was built in our laboratory If a target object is placed beyond the motion range of the manipulator itself, the look-ahead control scheme will be evoked and automatically generate motion of the mobile platform such that the whole robot system will make an approach to the object until the arm comes close enough to the object With this proposed coordination scheme, visual sensing of the object and resulting approaching motion of the manipulator and the platform are integrated in a natural way This report presents preliminary results of the recognition performance of a stereo camera and the dual-arm mobile manipulator with simulation and experimental results of the new robot system.

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Purpose of this study is to explore a stable walking of quadruped robot based on sensory information, especially data from an accelerometer mounted on the robot. In order to improve smoothness and stability in walking under various ground conditions, acceleration signals of the robot's body are measured and analyzed AIBO ERS7 is adopted as a test bed of the experiment With a limited computational capability provided by AIBO, we aims at achieving computationally viable, yet efficient method for the stable walking of quadruped robot

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This paper presents a navigation strategy of a wheeled mobile robot in an outdoor obstructed environment A laser ranger finder and GPS sensor are equipped on the mobile robot in order to perform sensor-based navigation without any a prion knowledge about its environment. Look-ahead control is adopted to steer the mobile robot In addition to the obstacle avoidance scheme, a way-point navigation system is implemented and then evaluated on an odometiy-based approach and GPS-based approach for a tracking performance. We participated m a robot competition called Tsukuba Challenge 2011 to verify the proposed approach Also, we adopted Kalman filtering to establish and integrate sensor information

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