Textbooks and common sense still have to be rewritten in MEMS areas, because knowledge is not matured in micro/nano science. Examples are presented in wet etching of silicon and fracture of silicon microstructures. It is argued that interdisciplinary research collaboration is quite effective and essential for solving such problems.

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In the past decades, the application of microelectronic technology to the fabrication of mechanical devices stimulated emerging research in micro/nano sensors and actuators. The versatility of semiconductor materials and the miniaturization of VLSI patterning techniques promise new systems with better capabilities and improved performance-to-cost ratio over those of conventionally machined devices. This talk will discuss MEMS/NEMS technologies and it applications to information devices, such as the design, fabrication and testing of MEMS/NEMS force and strain sensors to monitor disk/head contacts. Specifically, a micro pressure sensor and a pitch and roll motion sensor have been designed, fabricated and tested for possibly applications in the field of information devices.

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Rotating magnetic data storage systems are providing solutions in a growing digital world, facing expanding challenges in satisfying end-user needs. Various critical customer attributes are explored and how HDD mechanical technology is evolving to meet these needs.

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This paper discusses the need for multi-layered support for assuring active safety of transport systems. It also argues that a machine-initiated trading of authority may be indispensable even in the framework of human-centered automation.

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The measurement of electromagnetic fields, using SQUID magnetometer, generated by activation of the human brain and application to the interface technology of the human adaptive mechatoronics (HAM) system are introduced.

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This paper provides a new warning method for increasing drivers' sensitivity for recognizing hazardous factors in the driving environment. The method is based on a subliminal effect. The results of many experiments performed with six subjects show that the response time for detecting a flashing mark tended to decrease when a subliminal mark was shown in advance. This paper also proposes a scenario for implementing this method in real vehicles.

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We have conducted basic experiments for applying acoustic information to engineering problems. We asked the subjects to execute lifting while listening to the sounds, and we measured resultant lifting-force. We focused on an artificial sound as acoustic information aiming to expand the range of magnitude of lifting-force that is exerted by human. Especially, we attempt to clarify the acoustical features that artificial sound should have for making lifting-force much smaller. We indicated that lifting-force was made small in case of artificial sound as same as in case of onomatopoeia.

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Sensor shoes for measuring foot pressure distribution were developed and the analysis method to discriminate the user's movement from the foot pressure distribution was examined. Seven actions such as running and walking stairs could be respectively discriminated from 10 feature quantities extracted from 3 sensors by linear discriminant analysis and from six discriminant functions using feature quantities extracted from five sensors by canonical discriminant analysis. The evaluation results showed the high accuracy of behavior recognition.

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This paper addresses a new cooperation technique for multi-agent systems. This technique is based on human social behavior. Multiple robot cooperation has a potential to flexible and adaptable to environment and task variations. In this paper, the personality of each agent is controlled autonomously by interaction among agents. We especially focus on human behavior imitating other persons who work well. We implement an egoistic parameter and an altruistic parameter as personality to the agents. By the combination of these parameters, the personality is decided. Each agent updates these parameters automatically every constant time to improve performance of the whole system.

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Tripod parallel mechanism has three fixed length links and achieves six-degree-of freedom (6-DOF) motion with the coordinated motion of three links. In this paper, a tripod parallel mechanism developed by us is shown. And then, the vector analysis and the derivation of position of bottom end part of link for the attitude of platform are presented. Finally, the numerical simulation of our analysis and experiments are presented.

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Most natural phenomena are explained by complex systems science. Since tactile sensing is dominated by the nonlinear contact problem between object and finger surfaces and is recognized in nonlinear brain systems, it is closely related to complex systems science as well. We consider two phenomena caused by complex systems related to tactile sensing: Stochastic Resonance (SR) and tactile illusions. Elucidation of these mechanisms provides important hints to develop robotic tactile sensors and tactile displays. Since tactile sensing is performed by contact and brain activity, both mechanical analysis and neuron simulations are required to elucidate the complex systems phenomena in tactile sensing. In this paper, we outline our continuing project and neuron simulations using a Hodgkin-Huxley model.

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This paper studies an algorithm to judge moving and stopping status of distribution equipment from continuous vibration measurement. The key for this algorithm is a decision of threshold level, which differs according to the distribution equipment. For this end, supervised machine learning, which decides the proper threshold using the result of PHS location measurement as a training data is employed and fundamental effectiveness of algorithm is confirmed.

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Focusing on the PHS positioning service used in physical distribution of logistics, a positioning error offset method for improving positioning accuracy is invented. The PHS system has a defect that the measurement errors are large ranging from several ten meters to several hundred meters caused by the fluctuation of radio waves by buildings around the terminal. In this research, an error offset method is developed which learns patterns of positioning results (latitude and longitude) containing errors and the highest signal strength at major logistic points in advance, and matches them with the new data measured at actual distribution processes according to Mahalanobis distance. Then the matching resolution is reduced to 1/40 of the conventional error offset method.

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This paper describes the development of lever type Vickers hardness standard machine according to the requirements of ISO6507-3 by NIMT (National Institute of Metrology Thailand). According to ISO6507-3, the standard machine must pass both direct verification and indirect verification. The direct verification requires checking four parameters: test force, testing cycle, indenter shape, and diagonal measuring device. The most difficult parameter to control is the testing cycle. In testing cycle verification, there are three parameters concerned: approach velocity of the indenter shall be 50 μm/s. to 1 mm/s, the duration of application of the test force shall be 13 s to 15 s, and time for application of the test force shall be 6 s to 8 s. The uncertainty of time shall be within ±0.5 s of each parameter. After the machine was modified, the testing cycle of machine can be automatically and precisely controlled by PC with well-designed interface software. The behavior of testing cycle of NIMT Vickers hardness standard machine was detected by using force sensing element and displacement sensor. We can successfully control the approach velocity in 5 μm/s resolutions, the duration of application of the test force and time for application of the test force in 0.1 s resolutions with ±0.5 s uncertainty of measurement.

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Since the relationship between applied voltage and displacement, which is caused by the voltage, shows a hysteresis loop in the bimorph piezoelectric element, we produce a control system for a piezoelectric actuator based on a multi-layer artificial neural network including feedback connections to compensate the hysteresis. After learning the hysteresis loops including the minor loops, the neural network simulates these hysteresis phenomena with very high accuracy. A series of verification tests was performed on a parallel type two-dimensional actuator composed of two bimorph piezoelectric elements and two small links connected by three joints. The network provided a voltage history for several sizes of circular trajectories in two-dimensional space.

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One of the processes for having products with better quality is agricultural pest control. One typical way is wrapping a medical band around the tree. Robots can take this responsibility without any problem. A two-wheeled balancing robot was chosen for this project. Robot's structure is one of the important factors to design a two-wheeled balancing robot. Two different ways, for balancing the robot, are considered, which are: using the DC motors or sliding the weight across the robot's base. For keeping the robot's balance rapidly a quick response is required from microcontroller.

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There are kinds of flexible objects in house, for example, papers, rubbers, clothes are the typical objects. Therefore, a home service robot is needed to operate such flexible objects. However, to operate these objects has not established because these objects have characteristics that are different from each material and variable its form. In this paper, a modeling technique with Neural Network to predict behavior of flexible objects are proposed. Finally, the validity is verified by some experiments.

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This paper addresses the zutonomous-decentralized cooperation converyance algorithm to improve the task efficiency by selecting a leader from other robots autonomously. This algorithm aims at coexistence of two exclusive features. One is the effectiveness that is a typical advantage of centralized control systems. The other is the adaptability and robustness to the environment which are advantages of autonomous-decentralized systems. From the several experimental results, the algorithm can improve the task efficiency in the cooperative conveyance task even including human operated agent. Finally, judgement indexes with interaction in order to select the leader is discussed.

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We have developed an external skeleton type body motion measuring device which enables us to measure the motion of upper-limbs 7 flexibility. And, we have also developed a software system, which can give a real-time displaying of the human body model image into a virtual space: the body motion was displayed using each joint angle calculated from the measured data. We constructed a system which has a function of motion instruction in virtual environment using above explained equipment.

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The proposed research project is to develop an on-line tester machine for evaluating the image quality of a camera lens that is used in a lens module in a cell phone. This tester is not only suitable for conventional solid lens, but also applicable to the developing tunable liquid crystal lens by using the conoscopy approach to measure focus length and its quality. On the other hand, the approach using a commercial inspection chart along with a automatic feeding machine is also adopted for a quick estimate on the focusing quality that is primarily based on Modulation Transfer Function (MTF). In addition to the MTF, the proposed tester aims to has other functions of measuring Effect Focal Length (EFL), Back Focal Length (BFL), Field of View(FOV), Field curvature, Distortion, Astigmatism, Lateral/Axial Color, the distribution of index of refraction and phase retardation pattern. The constructed tester is capable of measuring varied optical performance indices for the next-generation tunable lens.

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We are currently developing a Guide-Dog Robot for visually-handicapped person. In our concept, the robot should have a movable platform, human-machine interface and capability of avoiding obstacles. For leading them safely, the robot is required to detect their position correctly. At the same time, it is required to detect a direction that people are walking. In this paper, the algorithm for a human-machine interface to lead the people is proposed. Getting the position data of a person as follower into account would be considered by this algorithm. To realize such an intelligent leading, we propose the new algorithm that a robot detects the center of corridor and foot of the follower simultaneously with a laser range finder (LRF). Also, the prototype robot is verified that it can lead a person successfully and safely.

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This paper proposes a final-state control method in which the feedfowared input is generated by a sampled-data polynomial. The required memory size is drastically reduced because it only requires to store the coefficients of the polynomial. The effectiveness of the proposed method is evaluated by HDD benchmark problem.

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Improvement of positioning control is more important for development of hard disk drive (HDD). Therefore, high speed and high precision movement of the 0magnetic head positioning of HDD is currently being intensively investigated. One of positioning movement stages of the head from a current position to a target track is called seek control. In this research, a feedforward input design which provides fast movement of the head without excitation of vibrations is applied for the short span seek. In order to achieve this purpose, we apply the feedforward control based on NME (Nil Mode Exciting) profiler and input shaping, which was proposed by Nakamura for the high-speed switching maneuver of satellite "ASTRO-G" not to excite vibration. We evaluated control performances of the proposed method by using the benchmark problem.

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In this paper, novel solutions are provided for designing the disturbance filter where is significant plant dynamics within the bandwidth of the filter. The filter zero is designed appropriately so that the root loci originating from both the filter poles and the lightly damped plant poles go to the stable region under certain low gain condition. The stability margin especially the gain margin is dramatically increased. The resulting closed-loop systems can provide large gain attenuation at the resonance frequency, and thus have more disturbance rejection capability.

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This article proposes a controller optimization for given disturbances, i.e., fluttering NRRO, RRO, sensor noise, and torque disturbance. This run-out oriented controller design is based on a response surface method and provides an optimal controller that minimizes positioning error due to the disturbances. The proposed method is not only for controller tuning but also gives us a cue to seek a direction about which disturbance we should prioritize to be reduced from a viewpoint of system integration.

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To achieve 10 Terabit/in^2 magnetic recording density, the bit aspect ratio (BAR) is estimated to be ≤ 4 indicating track density of 1.6 to 3.2 MTPI. This is going to place tremendous challenges to servo-mechanical. In this paper, a projection of the required servo sampling rate and bandwidth to achieve 1.6 MTPI is conducted. A method using the preamble field of the data channel is proposed to detect the position error as well as the timing information to increase the sampling rate without increasing overhead. Dual stage control design with a conventional VCM actuator and slider-based MEMs actuator is also preformed to achieve 9 kHz servo bandwidth.

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Improving storage density by means of an enhanced servo system typically requires the reduction of variance of the Position Error Signal (PES). The variance of the PES is determined by both period and non-repeatable disturbances for which the characteristics are often not known a-priori during the servo algorithm design. Moreover, the servo control algorithm is often limited to a standard Proportional, Integral and Derivative (PID) controller as more complicated algorithms are viewed to be less robust. In this document it is shown how a standard (PID) servo control algorithm can be augmented with an additional feedback loop that can be tuned automatically by estimating the actual disturbance spectra seen in the PES. Adaptation to the disturbance spectra is done in lieu of possible model uncertainties in the servo actuator, guaranteeing stability robustness. As such, the control algorithm provides a Robust Estimation and Adaptive Controller Tuning (REACT) to disturbance spectra to minimize PES variance in high performance servo systems in data storage applications.

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Achieving higher tape densities requires a significant reduction in the position-error-signal (PES). The current state-of-the-art for controlling lateral tape motion is a well-tuned proportional-integral-derivative (PID) controller with notches and a large integrator for tracking. This controller is robust to changes in servo dynamics between drives and has desirable tracking properties. Even with these qualities, this controller does not meet the requirements for the next generation of devices. For the next generation of drives to function, the servo system and controller must reduce the 3-sigma value of the PES significantly while preserving the tracking and robustness characteristics of the current controllers. In this paper, we seek to improve upon the current PID-based control design by designing a high performance add-on controller to target lateral tape motion (LTM).

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There is a problem of the fish adhering to the metal grids of grill strongly during grilling the fish. We suggested the evaluation method for the measuring of adhesion force between grilled fish protein and metal before. In order to avoid adhering grilled fish to metal grids, we suggested two kinds of metal grids of grill which were micro-patterned not to adhere the fish. We considered that these micro-patterned metal grids of grills and fish soup decreased adhesion area. And these patterns were radial and circular for each rod axial. Furthermore in order to avoid the invasion of the fish soup, we introduced an ultra-hydrophobic DLC (UH-DLC) coating on both radial and circular for each rod micro-patterned metal grids of grills because the fish soup are included about 90% water. By using the micro-patterned metal grids coated with the UH-DLC, the fish soup did not enter to the grooves. Also we decreased the adhesion force between the micro-patterned metal rod (length of 30 mm) with the UH-DLC and heated fish soup drastically. Furthermore we made micro-patterned grids of grill (length of 188 mm) with the UH-DLC, and actually grilled a fish with it and measured its adhesion force with a push-pull gage. The adhesion force of radial-patterned grids of grill with SH-DLC coating was 40% lower than that of no-patterned grids of grill.

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Carbon Nitride (CNx) coating has been attracted materials as well tribological property, especially low friction coefficient. Recently, the authors have reported the mechanism of superlow friction as running-in process. During the friction between CNx coating and a Si_3N_4 ball in N2 gas, nitrogen atoms desorbed from the CNx coating surface by cyclic friction in nitrogen gas, structural reformation of topmost surface to low shearing strength was taken place, simultaneously. From the view point of nitrogen desorption from CNx coating, it was assumed that ultraviolet ray could break C-N single bond when the ray intensity exceeded C-N single bonding energy. In this study, we hypothesized that ultraviolet ray irradiation could make the CNx coating topmost surface graphitic without friction in N_2 gas. We carried out preparing the CNx coating irradiated ultraviolet ray as 254, 312, and 365 nm wave length, because the C-N single bond is 305 kJ/mol and the other ultraviolet rays are 469, 382, and 327 kJ/mol. Then these specimens were tested in N_2 gas to compare frictional property of with and without ultraviolet ray irradiation. CNx coating was synthesized with Ion beam assisted deposition method as 100 nm thickness on Si(100) substrate. Ar ion beam irradiated to carbon target, sputtered carbon was deposited on the substrate and nitrogen ion beam was irradiated to the specimen, simultaneously. Friction tests were done with ball-on-disk type frictional tester which was set in vacuum chamber and the test conditions were that normal load was 0.1 N, sliding speed was approx. 0.04 m/s, and counter material was Si_3N_4 ball with 8 mm diameter. Before the friction test, the vacuum chamber was evacuated to approx. 0.1 Pa, then nitrogen gas was filled into the chamber approx. atmospheric pressure. All specimens did not exhibit superlow friction coefficient at the initial of friction test, however, the coatings which were irradiated exhibited superlow friction phenomena after several friction cycles. We defined that the running-in period was friction coefficient which became lower than 0.05. All irradiated specimens exhibited shorter running-in period than as-deposit CNx. The average of initial several cycle frictions of as-deposit CNx exhibited 0.04, on the other hand, in the case of 312 nm ultraviolet ray irradiated CNx exhibited 0.01 or lower average friction coefficient. These results indicated that ultraviolet ray could break the C-N single bond, these broken bonds were restructured to C=C double bond, and nitrogen atoms desorbed from the coating as the cause of restructuring to N_2 molecule. The effect of ultraviolet ray irradiation on destruction of CNx was assumed as ultraviolet ray irradiation period. Some early studies of ultraviolet ray irradiation to DLC were reported that carbonaceous network included in DLC was completely destructed with long period ultraviolet ray irradiation. According to the destruction of these networks, we investigated the effect of long period ultraviolet ray irradiation on. Thus, the friction coefficient had not been superlow (such as 0.01 or lower), and it often exhibited high value such as 0.2 or more. The structural changing of CNx coating's topmost surface was important dominant to decide friction coefficient, and it was clear that ultraviolet ray irradiation period should be controlled to obtain superlow friction. The ultraviolet ray irradiation was conventional method compare with changing the coating condition, and it could exhibit shorter running-in period than as-deposit CNx coating.

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The tribological properties of patterned surfaces were investigated under lubricated conditions. Micropatterns were fabricated on a Si surface using a combination of photolithography and plasma etching. NiFe-film with a 150 nm thickness was then deposited on the patterned Si surface. We prepared four kinds of patterned surfaces: dimple, grating, bump and mesh patterns. The dimensions of the patterns were: size 30 to 40 μm and depth 10 to 12 μm. Friction tests were carried out using a pin-on-plate tribometer. The results showed that the friction coefficients of the two reverse patterns showed very similar tendencies and that circular patterns had a lower friction coefficient than did the rectangular patterns at a high bearing characteristic number. The surface geometry of the Si surface did not affect the friction coefficients at a low bearing characteristic number.

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