When considering resource saving and environmental safety in automobile, electric drive technology is one of the solution for it. Electric axle drive with torque vectoring (eAxle), which is being developed by Schaeffler, is modular system with traction system, transmission and electromechanical torque vectoring (TV). It is possible to operate torque vectoring independently of traction torque due to the fact that traction torque and torque vectoring torque, which are generated by traction motor and torque vectoring motor, is transmitted to both axle via planetary gear differential. In case of conventional differential which is used bevel gear set, torque vectoring motor have to be rotated with differential gear set when torque vectoring torque is applied to pinion gear of the differential. And the system consists of coaxial traction motor and planetary differential make high power density system. eAxle is effective not only resource or CO_2 saving by electric dive but also improvement for vehicle dynamics by the torque vectoring system.

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In the process of hypoid gear manufacturing, we normally check the tooth bearing ,patterns in order to confirm their final qualities. But sometimes insufficient bearing patterms worry us by various reasons. This paper tells that we could reduce such defects considerably by manufacuturing the hypoid gear sets in complete pairs through all processes.

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Lubricants can contribute to save energy by adjusting viscosity and friction characteristics. In generally, it is attained by decreasing the viscosity. However, thoughtless decreasing viscosity can lead to machine troubles, such as seizure or wear, by the shortage of oil film strength. Therefore, lubricants are requested to improve extreme pressure performance and reduce friction. Energy-saving hydraulic fluid which we developed shows low friction coefficient. Therefore, it can reduce more electricity consumption than marketing oil in vane pump bench tester. In actual equipment, it shows 7% of energy-saving effect. Energy-saving gear oil shows high extreme pressure performance and high fatigue life. It can extend the machine life. In actual equipment, it shows 10% of energy-saving effect in same viscosity grade, and shows 19% of energy-saving effect in lower one viscosity grade.

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In this lecture, we discuss characteristics of cm-scale dynamics, i.e., insect world dynamics, which is not strongly affected by gravity and introduce mobile robots with abilities based on such scale effect. While a volume force such as gravity and a surface force such as air resistance and friction are proportional to the length cubed and the length squared, respectively, a muscle force is proportional to the section area. Therefore, tiny insects decrease own weight exponentially and increase the surface force and muscle force relatively. This is why they fly without difficulty, accelerate largely, turn sharply, and cling on a vertical wall easily. The butterfly-style flapping robot with the wing span of 10cm and the weight of 0.5g which was developed based on this design principle, i.e., scale effect, realized flapping frequency of 10Hz and take off of 10G. Moreover, the legged robot with the body length of 5.5cm and the weight of 9g ran at velocity of 11 body-length/s on the ground and 5 body-length/s on the water and the claw-type robot with the body length of 8cm and the weight of 13g climbed up and down a vertical wall.

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The swimming motions of animals are quite interesting and useful from the viewpoint of science and engineering. Three dolphin-like robots and a swimming humanoid which were developed by the author's group were introduced in this paper. The dolphin-like robots of Type 1 and Type 2 were developed in order to investigate the performance of the steady straight swimming. Type 1 had one air motor to actuate the caudal fm and one passive joint at the root of the fin. The total length of the robot was 1.75m. The maximum swimming speed of 1.15m/s and the maximum propulsive efficiency of 65% were achieved. Type 2 had the similar structure with Type 1 although the main joint was actuated by an electric motor whose maximum power was 7.4kW. The maximum swimming speed of 1.9m/s was achieved. Type 3 was developed in order to investigate the performance of the maneuverability. A loop-the-loop motion and three-dimensional motion in the water were realized. The swimming humanoid was developed for research of human swimming. It had 20 motors inside and the body size was half of an actual competitive swimmer. The swimming motion in a circulating water tank and the free swimming in a swimming pool were realized, respectively.

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A robot control system requires a feedback controller and reference motion pattern. However, because of the phase lag of the closed loop system, the generated motion does not coincide to the reference pattern. Moreover, the reference pattern has time-constraint. Because of these reasons, the robustness of the motion will be low. On the other hand, the autonomous controlled system based on an orbit attractor overcomes these problems, however, it requires a realizable motion pattern that satisfies dynamical consistency. In this report, we introduce a motion transformation method to obtain the realizable motion pattern. The relationships between joint angles, angular velocities and accelerations are represented by a product of a matrix, and the motion capture data is transformed to the robot motion.

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An analogous relationship exists between the kinematic structures of proteins and robotic mechanisms. Using this analogy, we attempt to understand the motions of proteins from the perspective of robot kinematics. As a part of this study, we show a method for predicting the internal motions of proteins using data from the Protein Data Bank. The protein model used in this method is simple; it comprises main chains and linear springs between the alpha carbons. The main chains are considered to be robot manipulators that control the positions of the alpha carbons or the distances between them, where the dihedral angles on the main chains correspond to the joint angles of robot manipulators. We apply forces in static equilibrium to the model, evaluate the deformation caused by them, and decompose motions into modes according to structural compliances. Despite being a simple model, the results are almost consistent with the measured internal motions.

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Unlike typical high precision machines assembled from prescreened parts that have been produced from appropriate materials through the most suitable manufacturing processes, most MEMS (micro electro mechanical systems) devices do not have such luxury due to the limited options in materials and processes available from the standard semiconductor fabrication technologies. In the field of MEMS design, it sometimes urges us to put more than one functions into a single component or layer, by considering the best use of the material properties and processes. In this paper, we use two examples of our MEMS application devices in micro optics and radio frequency to introduce such integrated design concept behind the developed microstructures.

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This paper introduces driven methods for curled-up type electrostatic micro actuator made of thin film metallic glasses. One of the methods achieves analog motion over the full range of its stroke without closed loop control system. The device consists of a curled-up moving electrode that delivers large deflection in the out-of-plane direction and a taper-shaped base electrode. A prototype device achieves analog motion for 70% by rectangular AC voltage from 0V to 400V. Another method removes remnant charge that can cause a moving electrode to "stick" to its insulator and demonstrates the effectiveness of the method experimentally. The method is applicable to many types of MEMS because it does not require any change to the actuator fabrication process, structure, dimensions or materials. The only modification is to the waveform of the applied voltage.

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Many types of electrostatic microactuators have been reported. However, these actuators generally generate small force and low power. We proposed the novel driving principle of the microactuator that makes electrostatic energy/force collaborate with the elastic energy/force, and the actuator driven by the principle was named Energy Conversion-type Micro Actuator powered by Collaboration of Electrostatic and Elastic energies/forces, and EC-Macbee for short. This driving principle can be realized by using non-linear spring and the non-linearity makes the microactuator highly effective. Therefore, the design of the non-linear spring is very important. A few type of the non-linear spring was designed by using the FEM analysis. Mechanical performance of the micro actuator was also evaluated. Initial generated force of microactuator with one type of non-linear spring is about 1000 times higher than that with linear spring. The effort to fabricate novel microactuators having non-linear spring is carried out for confirming the novel driving principle and evaluating the performance of them.

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Because of the progress of Internet and search engine represented by Google, the value of idea is increasing instead of the value of knowledge. MindMap is a famous and useful method to support imagination and association. However, to make the MindMap by oneself causes the partial knowledge and idea. From this viewpoint, we have proposed the idea generation support system by using the shared knowledge made by the colleagues who have same background and Google suggest. To examine the effectiveness of shared knowledge and Google suggest on the idea generation, we performed a couple of experiments. As a result, the performance by using the proposed system with shared knowledge was superior than others, and also the subjects tend to prefer the proposed system with shared knowledge.

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In face-to-face conversation, embodied rhythms between speech and body movements such as nodding are mutually synchronized between talkers. This synchrony is called entrainment in communication, and it allows sharing of embodiment in human interaction, which plays an important role in human interaction and communication. With a focus on embodied entrainment, we have developed the embodied communication system for mind connection (E-COSMIC) by applying the entrainment mechanism of embodied rhythms of nodding and body movements to robots and CG characters in verbal communication. E-COSMIC comprises an embodied virtual communication system for human interaction analysis by synthesis and a speech-driven embodied interaction system for supporting essential human interaction and communication based on the analysis. A human-entrained embodied interaction and communication technology for an advanced media society is introduced through some applications for empathy by embodied entrainment.

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GaN-based power devices have been expected to overcome the performance limit of conventional Si-based devices and enable highly efficient power switching systems. Technical issues have been mostly solved for the commercialization so far and the remaining tasks are to find more suitable applications and extract the full potential of the superior material properties. In this paper, we present state-of-the-art GaN-based power devices on cost-effective Si substrates and their applications to power switching systems. Novel Gate Injection Transistors (GITs) with normally-off operation enable highly efficient operations of isolated DC-DC converters in power supplies. The above results demonstrate very promising potentials of GaN based power switching transistors.

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Thermal design was performed for the power source of mobile electronic devices based on micro solid oxide fuel cells (micro-SOFC). To operate this power source in the devices, it was necessary to archive thermally self-sustaining and low surface temperature to prevent harmful damage to other electronics. One-dimensional thermal analysis revealed that high thermal insulator which prevented thermal radiative conduction and vacuum insulator could archive the requirements. The thermal insulation package based on vacuum insulator was designed and evaluated by FEM simulation. The result suggested that thermal conduction through the support was significant and the design should be modified to prevent thermal conduction and reduce the surface temperature.

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In order to realize high added value energy conversion system, miniature fuel cell with biomass-derived hydrogen system was discussed. Biomass-derived fuel is widely thought as the most favorable energy source. However, the high cost for producing fuel with utilizable form is a big problem. Therefore, a novel energy conversion system, in which the cost of fuel is negligible and some advantages are expected, is desired. Energy source for portable electronics devices with renewable energy can be a good candidate, and we launched this new miniature fuel cell project. Preliminary power generation was demonstrated with biomass-derived hydrogen. Voltage boost from 0.5V to 3.3V was also realized with an in-house power conditioner.

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First, the author personally looks back to the recent research and development of micro energy sources. Research in this field has started with micro fuel cells and micro engines in the late 1990s. 10 years before, the micro fuel cells were expected to partially replace batteries in laptop computers, mobile phones etc., but finally they could not compete with the batteries, which also improved considerably in this decade. After the micro fuel cells and micro engines, energy harvesters are now correcting much attention as "eternal" energy sources of wireless network sensors, which will be useful for energy saving and infrastructure health monitoring. The author describes a key point for successful development of energy harvesters, and finally expresses personal expectation and encouragement to the challenges of micro energy sources to exiting batteries.

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For many years, motion analysis has played a very important role in the medical and sports fields. However, conventional motion analysis method needs large space and has many restrictions . Therefore, in medical fields, the conventional method is limited to laboratory research and can't be used in everyday applications. These problems can be resolved by using wearable sensor systems. Lately, many researches have been done on wearable sensors. Therefore, by using wearable sensors, motion analysis will helps many patients efficient recovery. On the other hand Numerical simulation using multibody dynamic analysis for human body helps to understand what is going on. Recently analysis method has become to be very powerful to understand complex phenomena and demonstrate what kind of rehabilitation is most effective. In the fields of sports training, measurement system and analysis method is considered to play similar role as in medical fields. In the near future, combination of wearable sensors and multibody dynamic analysis will plays much more important role.

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This paper introduces the wearable motion sensor system for motion analysis and the application to sport fields of this sensor system. We have developed the measurement system installing the inertial and magnetic field sensors as the wearable motion sensor system, and we have mainly applied to the motion analysis of snow sports. The wearable motion sensor can simply measure the motion by attaching to the equipment and body segments. The inertial sensor measures the angular velocity and the acceleration. Furthermore, the 3D posture can be estimated by applying the sensor fusion, and the inverse dynamics analysis and the velocity estimation can be used by combining the force sensors and the GPS receiver. The performance of motion sensor and the measurement method are progressing on a daily basis. Therefore, the wearable motion sensor system will be much further applied to the motion analysis in sports and other fields.

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The purpose of this study was to investigate how non-muscular internal forces coordinate the golf swing movement. To this end, energy based motion analysis was introduced. We elucidate how energy produced by muscles is delivered to the club, through the synergistic action of non-muscular forces. This indicates an internal force transfers the energy among segments. This works as an energy pipeline among the adjacent segments, although it does not affect the entire energy.

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The purpose of this study is to introduce the contribution of the joint torques of human to the generation of parameters of human movements. The equation of motion for multi-segment model is obtained from the combination of 1) the equations of motion for individual segments, 2) the equations for constraint condition in which adjacent segments are connected by joint, and 3) the geometric equations for constraint axes of joints such as inversion/eversion axes of the elbow and knee joints. The contribution of the joint torques to the parameters is derived from the dynamic equation. The contribution consists of three parts, such as, total joint torque term, motion dependent term, and gravitational term. The total joint torque term can be, furthermore, divided into each joint axial torque term. The motion dependent term makes significant role for generating end-point speed of linked segment systems, particularly, in high-speed swing motion, such as, tennis serve, baseball pitching and batting motions. The motion dependent term is mainly caused by linear and angular velocities of the segments. Since these velocities are the results of joint torque and external joint force inputs into the system, we have proposed a converting algorithm of the motion dependent term into joint torque terms, external joint force term, and gravity term according to a recurrent equation with respect to the generalized velocity vector of the discrete time system.

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This paper describes a human gait simulation system with a precise neuro-musculo-skeletal model. The neuro-musculo-skeletal model incorporates 14 rigid bodies, 19 degrees of freedom, 60 muscular models, 16 pairs of the neural oscillators, and other neuronal systems. The proposed simulation system is computed based on forward dynamics, and takes not only kinematic data but also in vivo dynamic data such as energy consumption information into consideration, so that the resultant locomotion patterns are natural and valid from a biomechanical point of view. By changing the search parameters and the evaluative criteria of the numerical search method, various locomotive patterns such as normal gait, pathological gait, and running can be synthesized. The model can also realize stable walking patterns against a mechanical disturbance. This capability creates a novel application of human gait simulation systems, such as rehabilitation tool design and consultation for physically handicapped people.

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In an evidence-based rehabilitation context, establishment of a new ankle-foot orthosis (AFO) design method is required to make each user obtain a mechanically appropriate AFO which fits to the individual physical condition. In this article, we constructed a three dimensional neuro-musculo-skeletal model for walking simulation of a person with hemiplegia and generated gait patterns with or without AFO. Circumductive motion of the affected lower limb was observed at without-AFO condition, however the maximum magnitude of the compensatory movements were significantly reduced at AFO wearing conditions. Among four stiffness conditions of AFO, which caused different plantar flexion stiffness around ankle joint, energy consumption rate did not indicate significant differences, while the external rotation angle immediate after heel contact increased with gain in the plantar flexion stiffness of AFO. This result indicates the possibility to infer effects of AFO characteristics to wearers' gait prior to clinical trials.

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Application of large-scale parallel computational fluid dynamics to industrial problems is discussed, with its focus on vehicle aerodynamics. Issues to realize the industrial CFD using high-performance computing environment are mentioned in the context of mesh generation and the peak performance of application software. Capability and limitations of both unstructured and structured grids are demonstrated by considering the complicated and deficient CAD geometry data used in real product development process and the near future computer architecture. Finally it is discussed that how such HPC-CFD helps to realize innovative industrial processes.

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A future issue of CFD studies applied to the simulation of flows with additional complex physics is briefly addressed. We name this field Multi-physics CFD. A number of unresolved multi-physics problems have been founded in industrial problems, e.g. condensation, cavitation, erosion, and icing in turbomachineiy. Current status of two in-house codes developed by our group: Numerical Turbine(NT) and Supercritical-fluids Simulator(SFS) are briefly introduced to explain how multi-physics CFD can solve such complex flow problems in industrial applications.

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Computational Fluid Dynamics (CFD) is very powerful and effective. However, in order to master CFD effectively, specialized knowledge and technique and long computing time and high cost are still necessary. On the other hand, detailed and large-scale computing models are not always necessary in engineering. In most cases, analytical results are required not in detailed but in a short of term, therefore simplified CFD method is expected in engineering. In this paper, expecting for development of simplified CFD method, existing engineering problems about CFD of some steel making plant and process are presented.

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We have examined the plastic deformation behavior of Mg_<12>ZnY phase having the so-called "chemical and structural modulations synchronized long-period stacking ordered (LPSO) structure". As one of the characteristic features of the deformation behavior of the synchronized LPSO phase, formation of deformation kink bands is frequently observed in deformation under the condition that the operation of basal slip is prohibited. The deformation behavior accompanied by the formation of deformation kink in synchronized LPSO phase was examined by comparing the behavior in the hcp-Zn single crystal. Deformation behavior of the directionally solidified LPSO phase crystals was examined by dynamical observation using digital microscope and SEM-EBSD analysis. The characteristic features of the deformation kink band in the LPSO phase and Zn single crystal showed many similarities, but some differences were also confirmed.

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Micro-sized specimens were prepared from an LPSO phase of a directionally solidified Mg-Zn-Y alloy and the tensile properties of the LPSO phase were examined by using the micro-mechanical characterization technique. A directionally solidified Mg_<85>Zn_6Y_9 alloy with an LPSO phase was fabricated by using the Bridgman method. Micro-tensile specimens with a gauge section size of 20×20×50μm^3 (hereafter, DS specimens) were prepared from the directionally solidified alloy by focused ion beam (FIB) machining. The tensile direction was set to be approximately 45° from the c-axis of the LPSO phase, that is, the slip plane of the LPSO phase. Further, after applying a compressive load to the directionally solidified alloy to introduce kink bands into the LPSO phase, we prepared similar micro-tensile specimens from the kink band region (hereafter, kinked specimens). The yield stress of the DS specimen without the kink bands was 28 MPa; the specimen work-hardened moderately and then fractured after reaching the maximum stress of 51 MPa. After the tensile test, slip bands corresponding to the basal slip of the LPSO phase, were observed on the specimen surface. On the other hand, the yield strength of the kinked specimen was 65 MPa; this specimen work-hardened rapidly before reaching the maximum stress of 82 MPa. However, the plastic elongation was considerably small, and the specimen exhibited a brittle fracture. The surface observation of the kinked specimen indicated that the slip was suppressed by the kink band, thereby, causing inhomogeneous deformation.

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By using our multi-phase-field and finite element dynamic recrystallization (MPFFE-DRX) model, where a multi-phase-field dynamic recrystallization (MPF-DRX) model to simulate the DRX microstructure evolution and large deformation elastic-plastic finite element (FE) method using J2 flow theory to evaluate macroscopic mechanical behavior are coupled, we performed nonuniform compression simulations of a cylinder with LPSO type alloy.

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The "Washlet G"(Toilet Seat with Shower Unit), which is authorized by the "Mechanical Engineering Heritage" of the Japan Sciety of Mechanical Engineers, is said to have revolutionized Japanese toilet environment and custom. However, its success was indivisible from the diffusion of seat-type toilet bowls (so called "western type toilet bowls"), and the diffusion of flush toilets. This paper presents the history of development of Japanese flush toilet. First, efforts for domestic production of the western style toilet bowl are introduced. Next, the change of the Japanese flush toilet products and growth to the manufacturer of the World's standard product are described. Finally, the present situation on the toilet including the Washlet and their future are mentioned.

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Since ventricular assist devices became smaller and more durable in this decade, patients can go out of hospital and return to jobs. To promote research and development (R&D) and to accelerate the approval review processes of medical devices the METI published in 2007 the R&D Guidance for artificial hearts, and the MHLW published in 2008 a Notification by Director regarding the evaluation criteria for artificial hearts. Then two kinds of implantable ventricular assist devices were approved in 2010 and simultaneously the doctor/facility qualification system was initiated by the academia. The role of academia has been recognized through these approval process.

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Clinical application number of ventricular assist devices (VAD) started to arise from around the year 2005 after very long period having not more than 100 cases per year and finally there are more than 5000 cases per year in these days with rapid growth rate. So the VAD market is now recognized as one of most promising medical device market. Two Japanese companies have successfully launched their VADs in Japan on Apr 2011, but they have struggled in the highly competitive global VAD market because the market is divided between two US companies, Thoratec and HeartWare. In this paper technical points that made them successful is presented using related patent applications and future technology development trend in VAD is discussed.

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The main role of cardiopulmonary bypass system is working life support device during open heart operation. Oxygenator which is a component part of cardiopulmonary bypass system adds O_2 to blood and removes CO_2. The type of oxygenator which is used most often today is hollow fiber membrane oxygenator which transfers O_2 and CO_2 through micro porous membrane. The design concepts of oxygenator are a low priming volume and a small foreign substance contact surface. The design of oxygenator is carried out by selecting a gas exchange membrane and structure, determining the specification which depends on the company's product concept. JMS original design which has circular pathway was developed based on the concept of "simplification of the blood pathway".

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Cardiovascular disease as cardiac infarction is referred to as one of the three major adult diseases, and the number of the patients is increased with each passing year. Now the method of stent placement, which is numerously used for treatment of the ischemia disease, was put to practical use about twenty years ago, alleviated physical and economic strains, and was uplifting quality of life. However, the market of Japan shows an excess of imports as in the case of other medical devices, and the manufacturing technology of small and medium-sized enterprises in Japan are not working well. Since its establishment in 2003, our company has been developing and commercializing the stents made in Japan, and reported below.

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Circulatory assist devices are essential medical equipment for the serious heart failure patients. In order to develop new devices, it is necessary to carry out hemocompatibility evaluation testing, such as hemolysis or antithrombogenic testing. Those testing in vitro are important evaluation method, followed by animal experiment in order to make clear the mechanical characteristics of the devices, concerning the hemocompatibility based on the shear stress generated in the device. Especially for antithrombogenic testing, the blood coagulability is critical for the thrombus formation for the improvement of the in vitro testing. We have tried to elucidate the relationship between the blood coagulability and the degree of shear stress, regarding to thrombosis using a rheometer. On the other hand, we focused on the absolute evaluation of the hemolytic testing, using microcapsule suspension as a standard test solustion. We succeeded absolute hemolytic testing of four types of commercial centrifugal blood pumps.

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Traffic accidents causing pedestrians fatalities accounted for 37% of all traffic accidents in 2011. Especially, elderly pedestrians have been very often involved in traffic accidents (67%), for which countermeasures have to be taken. In order to investigate situations under which elderly pedestrians crossing roads could be involved in traffic accidents, experiments to measure the timing of when elderly pedestrians judged to cross roads while a vehicle was moving to approach them, were conducted in the daytime, evening and nighttime. It was analyzed how an elderly pedestrian's judgment to cross a road could be affected by the variety of a vehicle velocity or a distance between a pedestrian and a moving vehicle. When pedestrians tried to cross the road from the right hand side, the distances judged by the elderly were shorter than those by the younger at higher vehicle travel speeds (40 km/h or more) at daytime. On the other hand, the pedestrians tried to cross the road from the right hand side, the distances judged by the elderly tended to become similar to those by the younger at higher vehicle travel speeds at nighttime under the condition of the high beam. Thus, we could see the effectiveness of vehicle head lamps for elderly pedestrians to recognize an approaching vehicle and judge to cross the road.

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Metal Additive Manufacturing Technology is coming into practical use gradually. We, as a member of ALPROT, which stands for Advanced Laser and Process Technology Research Association, developed a new Selective Laser Melting platform with a high-vacuum process chamber in collaboration with AIST (National Institute of Advanced Industrial Science and Technology). In this report, the trend of Metal Additive Manufacturing in the world and the development status of the Selective Laser Melting platform are mainly introduced.

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The Laser sintering & high speed milling hybrid machine (LUMEX) has been manufactured and sold by Matsuura Machinery Corp. since 2004. To develop this unique one machine one process manufacturing technology, we would devote our effort to its usage for other functional parts and the know-how of the laser sintering & high speed milling hybrid process, as well as continuing to develop the quality of the medical implants.

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In order to realize a high accuracy space structure system, shape and vibration controls using smart structures are studied. Two prototypes of smart reflectors were developed and investigated. One was a long smart beam system equipped with Macro Fiber Composites (MFCs) and the other was a smart reconfigurable reflector equipped with smart actuators. The smart actuator was designed for the smart reconfigurable reflector and it consisted of a piezoelectric stack actuator and a displacement magnification mechanism. Experiments of the shape and vibration controls of the long smart beam were carried out and their performance were investigated. The performance of the smart actuator was also investigated through numerical simulations and experiments. The results are reported in this paper.

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It has been proven that fiber-optic refractive-index sensors can be used for monitoring cure process of thermosetting resin. In the present paper, process monitoring of GFRP was conducted by embedded refractive-index sensors. The sensors were embedded in 0° and 90° directions of unidirectional GFRP laminates and in resin of prepregs in order to investigate effect of reinforcing fibers on refractive index of resin. The laminates were manufactured at 140℃ and pressure of 0.5 MPa by a hot-press molding device. The experimental results showed that the effect of reinforcing fibers had remained small until cure process finished, however thermal residual stress caused by reinforcements affected refractive index of prepreg at cooling. Therefore, it was found that cure index of FRP prepregs could be measured by refractive-index sensors. In addition, it appeared that the refractive-index sensors were available to monitor air voids in resin qualitatively during molding.

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The present study investigated crack visualization in metallic structures using time-domain reflectometry (TDR) with a two-dimensional (2D) microstrip line (MSL). The inspected structures acted as the ground layer of the MSL, and a film sensor comprising dielectrics and a microstrip conductor was stuck on the surface of the inspected structures. 2D inspection was enabled by covering the inspected structure surface with the microstrip conductor to compensate for the lack of information in the transverse direction. Crack visualization experiments were conducted using the proposed TDR with 2D MSL for different crack lengths and positions. The experimental results demonstrated that crack propagation could be clearly visualized.

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