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In the field of bio-engineering, there is a need for a specialized manipulator that protect targets from hard physical contact. The solution proposed in this paper is a system that controls micro flows to manipulate a micro-sized bio-target. The manipulation principle and system structure are presented. In addition, a simple model that uses physically observable parameters is constructed to capture the flow-target interactions following a chemically assisted flow visualization. The experimental results of a prototype are presented, and the feasibility is discussed. The purpose of this paper is to prove the feasibility of this manipulation method. Further developments are introduced, highlighting the full potential of the prototype.

Micro dispense mechanism Recently, micro-droplet dispensation has been required in printed-electronics (PE) technology. Devices with micro dispensing mechanism are of key importance in achieving a higher performance with these products. In fact, it is very difficult for the conventional dispenser to squeeze highly viscous liquid with picoliter resolution. This paper describes the development of a dispensing mechanism comprising a dispensing device andXYstage, both driven by the piezo impulsive force. The dispensing device is mainly composed of a pipette and a taper needle that is driven by a piezoelectric element. When the needle passes through the pipette, a droplet of the liquid adheres to the needle-tip end. A micro droplet can be transcribed to a target surface by bringing the droplet at the needle-tip end in contact with the target surface. On the contrary, in theXYstage, the small tables on the V-shaped grooves can be driven by the impulsive force generated by the mass connected to the piezoelectric element. TheXstage is stacked on theYstage, which allows fine positioning in the plane. In the experiment, an array of a small amount of 0.2-picoliter droplets was successfully developed on the glass plate.

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.

In order to investigate micro hardness and stiffness in a special chamber, the development of a small-force generator mechanism and a piezodriven microrobot is described in this paper. This small-force generator is simply composed of a Voice Coil Actuator (VCA) and the tandem leaf spring mechanism. The small force can be controlled by an electrical current, which is supplied to the coil and positioned precisely at the balance point with the parallel leaf spring with no mechanical friction. The full bridge strain gauges on both sides of the double leaf spring can detect a small force that is applied to the sample with a microindenter. This handmade small device can produce and verify small forces up to 17 mN with good linearity and a 50 µN resolution. The displacement of the indenter head can be also measured by the Linear Valuable Differential Transformer (LVDT) on the machine for monitoring the depth behavior of the indenter during the whole dwell time. The small force generator with the indenter can be implemented on the piezodriven microrobot to check the microscopic hardness and stiffness. This microrobot can move around the measurement area precisely step by step with 1 µm steps on a metal plate, so that the sample can be scanned with microscopic resolution in situ, such as in an SEM chamber. In the experiment results, the basic performance of microelasticity investigations with a certified hardness block was successfully checked and the indentation load-depth characteristics were precisely acquired on the path of the microrobot.

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.

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.

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.

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.