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Pickering emulsions comprising liquid droplets stabilized by solid microparticles have gained much attention in the field of cosmetics, inks, and drug delivery systems. To ensure that microparticles in Pickering emulsions are localized at the surface of liquid droplets, ultrasonic spectroscopy analysis combined with scattering function theory was conducted in this study. Two specific cases were investigated: (1) silica particles and liquid droplets independently dispersed in liquid and (2) silica particles effectively localized at the surface of the droplets. It was found that the core-shell model was effective for analyzing nanoparticles anchored at the surface of oil droplets. Conversely, it was found that an effective shell comprised of solid particles was no longer observed as the particle size or the distance between solid particles increased. When a large solid particle was applied, the ultrasonic spectra resembled those of conventional surfactant-stabilized emulsions without solid stabilizers.

Researchers and industrials from various fields are looking for reliable manipulators in a liquid environment. In this paper a tool for flow vitalization using chemicals to check the flows around the manipulated as well as a configuration for micro-manipulation are presented. Our research is bio-engineering oriented since we aim at manipulating a bio-target; a cell. It is challenging since these targets can be damaged easily through direct contact and are highly deformable. The successful manipulation would make the observation, selection or alteration of such targets easier, leading to great improvement in the medical and pharmaceutical fields. This paper discuss the primary challenges we face to achieve our goals. As a first step in a bigger project a first prototype was built, tested and analyzed.

We have proposed a surrounding environmental recognition method using conical scanning distance measurement for mobile robots. The conical scanning method has a high robustness against ambient light noise and its calculation cost is low. This report describes the principle of this method and the two implementations. The first application is the quadrupedal wheeled robot. The robot can recognize a stair in sight, approach to it and climb. A second application is the indoor-outdoor wheeled mobile robot. The robot can recognize its position and obstacles on floor from information of a laser range finder and a 3D ToF camera. The validity of this method was confirmed by these robotic applications.

We introduce an internet based crossover robot remote control competition project that is an international cooperative program based in Japan, China, Thailand, and Taiwan. This competition is an important component of a long-term higher education reform project aiming to develop a practice based innovative educational methodology jointly promoted by the Ministry of Education, Culture, Sports, Science & Technology of Japan and the University of Electro-Communications. The competition project includes two subjects: the competition itself and the communication and cooperation between students in two countries. The basic mode of the competition is a locally controlled robot and a remotely controlled robot cooperate with each other to complete some tasks. As a unique feature of the project, the student–student communication and cooperation are increased through a specially designed team organization structure that each team consists of two groups from different universities in different countries and the team members are required to cooperate through the internet to complete the competition. The competition has been successfully held four times and the results show it greatly benefits the students, and is expected to promote the development of the practice based educational methodology in the near future.

A microsurface measurement system that is composed of the microrobot with the indenter and a vision based navigation system is proposed for investigating hardness and stiffness of such microparts. Here the tiny robot with the electromagnetic legs and the piezo elements incorporates with an electromagnetic driven microforce generator. This force generator can provide small forces up to 17 mN with 50 µN resolutions and push down the microindenter to the surface. The displacement of the indenter head can be also measured by the Linear Valuable Differential Transformer (LVDT) on machine. Thus, this mechanism can generate the small force and monitor the depth behaviour of the indenter during whole dwell time. Since the overall size of this mechanism is small enough to implement on the piezo-driven microrobot, the tiny robot with the microindenter is capable tomove precisely step by step with 1 µm per step so that the microindenter could be penetrated anywhere on the sample surface. With the help of an image processing technique, the vision based coordination system with the local close-up view and the overall global view has been developed to identify the locations of small robot and the indenter precisely within ±3 µm accuracy over the working range. In the experimental results, several results that the indentation load-depth characteristics of the unhealthy human tooth are measured automatically at the specified point are discussed.

This paper presents a design of linear gain slope equalizer for correcting the linear gain distortion. It is based on the Bernstein-Stancu polynomials, where the well-known and readily available approximated of the desired transfer function are applied. As it is known that the Bernstein-Stancu polynomials have the several advantages. For example, there is a flexible parameter as a that can be used to adjust the magnitude response for the best result. If the parameter a equals to zero, it becomes to the classical Bernstein polynomial. In addition, the phase response is linear. As the results, the proposed method is capable of designing linear gain slope equalizer which is also shown to be efficient performance without degrading its phase characteristics. The stability of the approximated of the transfer function can guarantee with Mihailov's criterion.

In this paper, we describe the development of an orthogonal microrobot for accurate microscopic operations. To conduct the microscopic operation, a simple locomotion mechanism composed of one piezoelectric actuator and two U-shaped electromagnets is proposed. The orthogonal microrobot can move precisely in one-axis with the manner of an inchworm. We use permanent magnets so that this robot can fix itself on a steel surface when no voltage is applied. To provide XY orthogonal positioning, we connect one microrobot to another microrobot orthogonally. To realize cell processing, we arrange the three two-axial orthogonal microrobots on an inverted microscope. We load a simple micropump on right and left robots to hold biological samples such as an egg cell and to inject reagent solutions into biological samples. Finally, we arrange another microrobot between the other two microrobots to position samples. The whole cell processing device is very small, so we can easily set up the whole device to microprocessing instruments. In experiments, orthogonal microrobots succeeded in holding an egg cell with a diameter of 100 μm and sticking the pipette with a diameter of 5 μm into the egg cell under a specific GUI control system with a visual feedback function.

Recently, data traffic for satellite communications is increasing rapidly, due to various new purposes besides the conventional voice phone and facsimile. For the reason, it is necessary to realize high frequency communications, which is to be assured by high accuracy of tracking control of an antenna. To meet the needs, this paper aims at the accuracy improvement of conventional ship mounted tracking antennas by introducing H-infinity control. In this paper, the basic characteristics of tracking antenna are investigated by experiments and the model of the antenna for controller design is established. Based on the model, an H-infinity controller is designed and implemented to the antenna. Experimental results show that the tracking accuracy can be improved to /spl plusmn/0.3 [deg], which is five times higher than that by the conventional controller.

A new kind of the rotary encoder based on the magneto-optical (MO) storage is proposed. Using the MO methods, a small high-precision high-response rotary encoder can be realized. High precision is achieved by a two-stage process in which the code disk is firstly written using the direct transfer recording, and then rewritten using the corrections based on the measured errors. The systems for writing to, reading from, and evaluating the MO encoder are developed, with the optimal MO encoder reading and writing parameters determined experimentally. A trial MO encoder with a resolution of 9000 pulses/revolutions is created directly from a reference encoder, delivering an accuracy of approximately 2.8 in. The maximum resolution and response frequencies achieved are 18000 p/r and 400 kHz. After the corrected transfer recording, accuracies of 1.3 in at a resolution of 2250 p/r and 1.7 in at 9000 p/r are achieved.

For Above Deck Equipment (ADE) on a ship, it is necessary to perform experimental modal analysis (EMA) by base excitation. Existing EMA tools are designed to perform curve-fitting on the frequency response function of displacement or acceleration at measuring point to an excitation force. However, in case of experiment by base excitation, transmissibility of acceleration, that is, the ratio of accelerations between measuring point and base is to be used for modal analysis. A method, which makes modal analysis for base excitation possible by performing curve-fitting on the transmissibility of acceleration using existing EMA tools, is proposed in this paper. First, the relation of transmissibility of acceleration using modal parameters in case of base excitation is derived. Based on the relation, a new method for modal analysis is given and its feasibility for one D. O. F. system is shown by numerical calculation. Finally, the method is applied to the modal analysis of an ADE, and its effectiveness is shown by comparing experimental results with simulation results using the modal parameters obtained by the method.

This paper proposes a suppression of tremor effects, fluctuations caused by a user’s hand, on a handheld micromanipulator by means of a robust hybrid control scheme. The proposed control scheme is a combination between an explicit model predictive control and a PID controller. The advantage of the PID controller is a robustness. It is suitable for handling the holding angle changes. The explicit model predictive control provides the excellent tracking performance. In addition, the robust hybrid control can handle tremor effects successfully. The control objective is to achieve robust tracking performance, to dampen the vibration of the mechanism and to suppress a disturbance, a tremor. The experimental results are used to investigate the effectiveness of the proposed method.

In our previous work, robust control structure based on disturbance observer for a fast and precise fine motion mechanism has been proposed. The functionality of the controller was verified using one axis of precise X-Y table combined with-one axis fine motion mechanism. As a further step in this paper, the approach is extended to two-axes fine motion mechanism with a SCARA robot as a real system to realize the final purpose, that is, the development of high-precision mounting robot. First, the paper introduces a high performance robot system based on a SCARA robot coupled with a fine motion mechanism which was developed in our laboratory. Second, the paper presents a control scheme that enables correction of possible offsets of the end-effector relative to the target and compensation of the oscillations at the end-point. Finally, experimental results show significant improvements in end-point accuracy and settling time achieved by the novel configuration of the coarse/fine robotic system. As a result, a repeatability (3σ) less than 2 μm and the CP positioning error (3σ) less than 4.0 μm were achieved by the coarse/fine robotic system.

The characteristics of angle transmission mechanisms exert a great influence on the servo performance in the robotic or mechatronic mechanism. Especially, the backlash of angle transmission mechanism is preferable the small amount. Recently, some new types of gear reducers with non-backlash have been developed for robots. However, the measurement and evaluation method of the backlash of gear trains has not been considered except old methods which can statically measure at only several meshing points of gears. This paper proposes an overall performance testing method of angle transmission mechanisms for the mechatronic systems. This method can measure the angle transmission error both clockwise and counterclockwise. In addition the backlash can be continuously measured in all meshing positions automatically. This system has been applied to the testing process in the production line of gear reducers for robots, and it has been effective for reducing the backlash of the gear trains.

This paper presents a controller structure for a fast and precise fine positioner which can be attached to the end-effector of a classical industrial robot for assembly tasks. The overall control system consists of three elements: a position loop feedback controller, a feedforward controller, and a disturbance observer for the position loop. A useful method for compensating for the asymmetry and non-linearities of the piezoelectric based system is used as the first step in the design process. The robust feedback controller based on the disturbance observer compensates for external disturbances mainly from the coarse positioner. Precise tracking is achieved by the feedforward controller. Experimental results are presented to demonstrate performance improvement obtained by each element in the proposed robust structure.

Automatic garbage collection site for removing garbage from AMR and putting the garbage into garbage depot in good order has been developed. This system is composed of five subsystems: (1) A servo-controlled orthogonal type XYZ-crane; (2) A garbage bag gripper which has two rollers at the tip of its finger; (3) A sensor system to detect distribution of garbage bags on floor and on AMR; The irregularities of the garbage-bag can be detected as distance image by scanning ultrasonic range sensor; (4) A communication device using IR for communicating with AMR; (5) Computer system for control whole systems. Moreover an algorithm for determining suitable position to taking and putting garbage bag from distance image has been developed. The experiments using all of the above-mentioned subsystems have shown practicality of this system.

In this thesis, a new approach to Self-Positioning-System for an Autonomous Mobile Robot (AMR) is introduced. The system is composed of a set of small landmarks scattered inside of AMR working area and a reading system mounted on AMR. Each landmark is represented by a unique pattern made of polarizing film that is placed in a known fixed position. The panoramic scanning system is composed of a laser beam emitter and a detector of the reflected polarized light beam. When AMR approaches landmark's neighborhood, AMR can determine it's own position (x, y) and posture (orientation θ) by reading the landmark. By experiments, the system is able to determine AMR position with standard deviation of 10 [mm] or less and AMR posture with standard deviation of 1.0 [degree] of less when reading system inside of a circle (R=500 [mm] ) centered 800 [mm] away of the landmark.

This paper describes a marking robot which leaves a specific mark at the fitting position for various apparatus on the ceiling boards in large buildings. We have developed a prototype system and carried out an experimental assessment. The robot can move autonomously and locate itself at desired locations. Then it can draw specific figures on the ceiling board. In order to accomplish such jobs, the mobile robot is carrying a Self-Position Measuring System (SPMS) and a Marking System (MS). The SPMS measures the bearings of the surrounding pillars, so that the calculation based on triangulation can give the coordinates of its own position. The MS is composed of the X-Y-plotter-like drawing equipment and the lifting mechanism elevating it to the ceiling board. Experimental results proved that this system was able to mark a square and a circle with an error of ±l0 mm.

Recently, the demand for moving robots working at construction sites is increasing, and research activities are in progress. Unlike industrial robots working in factories, construction robots must meet more functional requirements because they must handle a variety of complicated jobs at construction sites. The robots must also be able to locate themselves. This requires a technique that enables the robot to measure coordinates indicating its position. This paper describes a new method to enable robots working at large building sites to precisely locate themselves and describes the principle of this system and experimental results.

The development of the instrumented indentation testing robot for bio materials with micro surface hardness and stiffness test is described. This micro surface measurement system is composed of the piezo-driven micro-robot with the indenter that can move to the measurement area precisely step by step with 1 μm per step on a metal plate and camera base coordinate measurement instruments. The position of the small robot can be controlled precisely by vision base navigation system. With the help of image processing technique, the coordination of the small robot can be identified precisely within ±10 μm resolution. Since the performance of micro hardness sensing is compared with the hardness standard block to certify its ability, the sensing head is implemented on a micro-robot. In the experiment results, the elasticity investigation with human tooth is successfully checked by the indentation load-depth characteristics.

This chapter describes a coarse-fine robot system for the purpose of precise mounting electronic components, has been described. The development of two-axis FP and its experimental evaluation were presented. The developed fine positioner consists of piezo-electric actuator and displacement magnifying mechanism with elastic hinge. The displacement magnifying system is designed by simulation based on finite element method. Using only the control of the FP, transient and residual vibration of the coarse positioning device has been compensated successfully. As the result, high speed and precision positioning can be realized by the developed coarse-fine mounting robot system. Experimental results demonstrate significant improvements in endpoint accuracy and settling time achieved by the novel configuration of the coarse-fine robotic system.