Robot localization is the problem of determining a robot's pose based on sensory information. This problem is consider one of the fundamental issues for autonomous robotics, hence its importance. Localization systems using wireless signal strength measurements have gained popularity in recent years, probably due to the proliferation of wireless Local Area Networks using Wi-Fi. Among these systems Gaussian Processes excel due to its flexibility and ability to model a wide variety of mappings. This paper presents an analysis and comparison of two different approaches for the localization problem based on wireless signal strength measurements. Our main motivation is the use of these learned mappings for robust localization.

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This paper describes a Non-Line-of-Sight (NLOS) satellites detection method for improving GNSS (Global Navigation Satellite System) positioning accuracy in urban area. In general, NLOS satellites which are shielded by obstacle such as buildings and elevated bridges cause large multipath errors in positioning results. Therefore, our method extracts obstacle area in a fish-eye camera image by projecting 3D map on it, and detects NLOS satellites existed on obstacle area. However, camera's position and orientation on 3D map coordinate are essential in projecting 3D map, and we estimate them using particle filter. As a result of evaluation test in urban area, it is confirmed the proposed method is effective on improving positioning accuracy.

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We propose a solution to the "map-to-text (M2T)" problem, which involves the generation of text descriptions of local map content based on scene understanding to facilitate fast succinct text-based map matching. Unlike previous local feature approaches that trade discriminativitv for viewpoint invariance, we develop a holistic view descriptor that is view-dependent and highly discriminative. Because the success of our holistic view descriptor depends on the assumption that the viewpoint is unique given a local map, we also address the issue of viewpoint planning that provides similar views for similar local maps.

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In this study, we address the problem the problem of visual robot localization using monocular vision sensor. The goal of visual robot localization is to localized the robot itself with respect to a view sequence map by incorporating sensor measurement from robot's vision sensors. To this end, the robot updates its current belief of self-position every time a new sensor measurement arrives. There are two popular approaches to this problem, Kalman filter and Particle filter approaches. The former is an efficient estimation using a Kalman filter, etc. when the initial robot pose is known. The latter is a robust estimation using a Particle filter, etc. when the initial posture of the robot is unknown. Since the two approaches have their own advantages and drawbacks, we here proposed a unified approach called GMM (Gaussian Mixture Model) filter that combines the advantages of two approaches. Our basic idea is to approximate the inherent multi-model belief distribution efficiently and accurately by using a mixture of Gaussian distributions. The effectiveness of the proposal method is experimentally verified using a real-world robot vision system.

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Kidnapping is a localization problem in which a well-localized robot is suddenly moved to somewhere else without any update to its sensors. This causes failures or faults in the autonomous robot. To solve this problem in an unknown environment, a new method for kidnapping detection in Simultaneous Localization and Mapping called Double Guarantee Kidnapping Detection (DGKD) has been proposed. It helps to determine whether kidnapping has happened, and classifies and detects which type of kidnapping it is. To verify its performance in a realistic and static environment, a mobile robot platform is constructed using a Roomba robot equipped with a laser range finder. Experimental results demonstrate the validity and accuracy of the proposed method.

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Autonomous mobile robots are required to understand surrounding environments for its localization and motion planning. This paper proposes a 3D mapping system using LIDAR and a triaxial inertial sensor. The system is based on "Velodyne SLAM" which is a state of the art ICP based mapping method using only point cloud data. In comparison to the existing method, the proposed method is robust to rotary motion and works for fast and large change of sensor position and orientation. We implemented the proposed method to the hand-held sensor unit, and evaluated its effectivity in varied environments.

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Many infrastructures like bridges and tunnels had been constructed during the steep economic growth age. In Japan, degradation of those infrastructures becomes a problem. Recently, using robots for the bridge inspection attracts attention. Checking using robots can cut cost. But area of the damage can't be identified, just look at photos of a damage part. Therefore, position estimation system for robots is very important. We have created position estimation system for robots by using speakers and a microphone. In addition, practical utility of one dimension has been confirmed. In this study, we have mounted a microphone on the robot and this system has estimated the position of the robot. The practical utility of this system was confirmed.

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RFID system is useful for mobile robot self-localization in an environment where RFID tags are distributed accordingly. It enables a mobile robot equipped with a RFID reader to detect the tags and localize itself in a simple way with high accuracy. Simultaneous localization and mapping (SLAM) has attracted immense attention in the mobile robotics literature. This paper analyzes the SLAM performances of an omnidirectional vehicle based on an RFID system with multiple readers at the bottom of a vehicle and the tags on the floor. We use the IC tags as the landmarks to build the map. The method has been tested on the simulated and real environment. Experimental results show the validity of the proposed method.

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A SLAM (Simultaneous Localization and Mapping) problem is major in mobile robotics field about past two decades. In order to solve the problem, a camera and a LIDAR (Light Detection and Ranging) are generally used. In contrast, this paper proposes a new solution for the problem using a magnetic sensor. Our method is simple since an observation model in RBPF (Rao-Blackwellized Particle Filter)-SLAM is replaced by that of a magnetic sensor. However, magnetic sensor-based SLAM has a problem that is so narrow measurement range of the sensor. To deal with the problem, we use a heuristic method to determine surround magnetic field. We conducted experiments in actual outdoor environments including loops and verified its accuracy by using a LIDAR. Through the experiments, it was shwon that our method can close loops and build consistent maps; magnetic and geometric.

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This paper presents a solution to the 3D-SLAM problem using low cost RGB-D sensors in indoor environments. For cluttered indoor environment it becomes important to safely navigate the robot from one position to another and 2D data such as scanning lasers do not provide enough environment information. We propose using a combined scanning laser and RGB-D sensor system using which rich 3D maps are built for robot to safely maneuver in a cluttered environment. A graph based SLAM approach is utilized to correct the robot poses and point cloud data are accumulated to generate the 3D map.

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Recently a RGB-D sensor "Kinect v2" is on the market, which is reputed to be available even in the outdoor environment. In this article, it was installed on a mobile robot and its performance in the outdoor was characterized. It was proven that the obtained point density is decreased, affected by infrared ray in a shine condition compared to dark condition. The Kinect v2 performance was compared with a Laser Range Finder (LRF). It was proven that dense point data of a road surface is successfully acquired by Kinect v2, whereas rather sparse data is acquired by LRF. Considering that a LRF itself scans laser beam on 2D plane, it was set on a swinging stage to obtain 3D data, making the obtained point density per space lower compared to Kinect v2. The robot usually follows a planned path to a command position based on odometry, which is periodically updated by a global positioning system (GPS). In case that GPS is not available owing to the radio wave occlusion by a tall building etc., Kinect v2 was used instead of GPS. It was proven that the robot can follow the planned path by detecting the road surface in such case without GPS.

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Recently, the development of the flying robot for navigation and security system in doors is taken notice. The goal of study is to realize a navigation system of the flying robot using the indoor positioning system with spread spectrum (SS) ultrasonic waves. It is difficult to detect SS signal when the flying robot is flying because of the signal interference caused by the propeller. Therefore, we discuss some solutions of this problem in this paper. As a result, SS signal can be detected by the way of surrounding with the sound-absorbing material around the receiver. Thus, we can expect to realize a measuring and a positioning.

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This paper proposes an order-preserving merging method of 2D range scans for enhancing our CIF-based scan matching algorithm which is a global scan matching algorithm using the CIF descriptors and a geometric constraint between keypoints. Our enhanced version of the CIF-based scan matching algorithm can perform global scan matching more robustly in a large cluttered environments without using an initial alignment. Through experiment in real environment, we confirm the validity of our method.

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This study is developing a robot that can make map data by using laser range finder and can estimate self-position by comparison between map data and wall getting by laser range scanner. This robot has a pressure sensor used to estimate floor level. we use ROS as a middleware during integration of these systems. In this time, we describe a method to build the environment map that is a combination of 3D laser range sensor and 2D laser range sensor.

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In recent years, research on motion control of robot in human living environment has been actively carried out. It's necessary to make a path planning of robot and estimate the human behavior s in order that robot can work in human living environment. In this research, human behaviors in some particular environments where can show the human walking characteristics have been observed and then we extract the human gait characteristics by calculating the displacement of human position information. And the similarity of each environment is calculated from the data of human gait characteristics and in the end human behavior pattern is estimated.

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In this paper, we introduce a new approach of mobile robot localization with microphone array and sound sources using pulse compression. The proposed localization method utilizes sound sources as landmarks, which are detected by the microphone array. Each sound source produces chirp signals with respective frequency bands, which sweep 2 kHz in 0.1 s. Pulse compression was executed for each recorded sound to enhance and identify the direction-of-arrival (DOA) of each sound source. The proposed method was evaluated by computer simulation. In the simulation, the localization error of the proposed method was approximately 51% lower than the method which separates sound using band pass filter. From the result, the proposed method indicates the robustness under the disturbances. This result contributes to the use of this method in the realistic, noisy environment.

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Moving from one place to another autonomously is one of the fundamental functions of mobile service robots operating in wide indoor environments. Such an autonomous movement requires a map and location information of a robot. In this research, we develop a system that a robot makes a map of a wide indoor environment and moves autonomously by estimating its position using the map. The system is composed of modules for SLAM, Explorer for automatically detecting unvisited regions, and DynamicController for stabilizing the robot motion. We also improve the accuracy of localization by estimating the initial position using the RSS information of Wifi networks. We successfully performed experiments on a wide-area map generation and on localizaiton without knowledge of initial position. Future work includes the implementation of functions such as guidance service.

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This paper describes a precision positioning technique that can be applied to vehicles or mobile robots in urban environments where there can be large GNSS multipath errors due to the obstruction of satellites by buildings. We propose a technique to realize multipath mitigation based on a satellite selection method that uses a "virtual fish-eye sky image generation" to exclude invisible satellites. In the proposed method, the position is estimated through the particle filter. We propose the method to compute the likelihood of the particle using the GNSS positioning based on the only visible satellites that are determined by the virtual fish-eye sky image generation. The evaluation results confirm the effectiveness of the proposed technique and the feasibility of its highly accurate positioning.

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The footstep planning for the hexapod robot in obstacle environment is proposed in this paper. The tripod gate is employed as the basic gate so that the footstep planning problem becomes the combinational problem of stepping one by one like a bipedal robot gate. The triangle shape can represent the tripod and its motion and its apex indicate the footstep pattern and the landing position of the foot. The landing position should avoid obstacles. A* algorithm is implemented to solve the combination problem evaluating the cost function which consist of the number of the stepping, the length from the goal and the penalty of colliding obstacles. Simulation results show the appropriate footstep in the obstacle environment.

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Passive dynamic walk is a highly energy efficient walking mode that do not use external actuators to control stable walk. There are some researches that apply upper body swing to a passive dynamic walker to achieve walking on flat or upslope walk. However, passive dynamic walk is unstable and it is difficult to keep stability for a long duration by applying oscillation. This research proposes the use of Constraining Sole Shape for the passive dynamic walker with external oscillation. By the effect of suppressing overshoot of leg swing, it is expected to achieve stable walk which synchronize the external oscillation. A number of experiments were conducted with upper arms swinging. The results show that the robot could continue to walk on a flat surface under a variety of oscillation frequencies.

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A low complexity and low cost modular quadruped platform is proposed for simulation, control, and experimentation. The modular design is possible due to the use of digitally configurable smart servomotors. A simulation integrated modular software framework used in conjunction with the hardware platform to provide online and offline control, simulation, and optimization. The framework is split into independent platform control, motor control, communications, and simulation modules that are tightly interconnected despite a high level of abstraction. Data control mechanisms are implemented to maintain time wise synchronization while allowing independent update rates.

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In this paper we discuss the dynamic walking algorithm for fast walking. In order to conduct smooth and fast walking, an acceleration and a deceleration are necessary. As a basic locomotion we use Longitudinal Acceleration Intermittent Trot gait which we presented before. An acceleration and a deceleration are performed while 4 legs support phase, this makes a robot be able to change the speed with fewer constraints. Additionally the swing leg trajectory which achieves 0 relative speed to the ground when the foot touch is implemented. In the end, the walking experiment was performed with proposed walking algorithm by using the TITAN-XIII. As a result the robot walked at 1.36 m/s.

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This paper describes a simple method for skating by small biped robot. Humanoid (biped) robots are generally slower speed and more energy than other robots during locomotion. Skating is one of the way solves their problems. We proposed a skating method by a biped robot which uses swaying motion. A biped Robot given angular velocity about roll axis gets propulsive force of skating when impulsive force arise between its support leg and the ground. We developed a small skating robot with 2DOF ankle joint a leg. With the robot, we achieved straight skating and turning skating. However, the robot has hardware problem. So, we developed a new model robot.

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We have developed one-legged jumping robots using crank mechanism. The robot has a spring and a motor and it succeeded in continuous jumping supported by a stand to restrain its motion in the vertical direction of one degree of freedom. In this study, we improved the one-legged jumping robot in order to remove the stand from the robot and to jump continuously without falling in three degrees of freedom on a vertical two-dimensional plane. The robot is constructed by adding a hip joint to the previous robot. We also developed smaller robot. Some experiments are conducted to verify the robot. The experimental results of implementing a posture stabilization control are shown.

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This paper addresses on a hunch of control scheme for multi-legged robots to traverse uneven terrain based on observation of the terrain, planning contact points, and walking control. A depth camera is used to observe the terrain. The contact points planning is based on graph search algorithm, A* algorithm. The walking control is based on a decentralized control, Follow-the-Contact-Point gait control. The proposed control scheme is verified by a computer simulation and experimental result.

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This report describes the design of a small-size quadruped robot driven by 13 pneumatic artificial muscles for high speed running. Each leg is driven by three artificial muscles, for swinging back and forth, and retracting. The extention of the spine is driven by one muscle. Trot and bound gaits are realized by open loop control on a treadmil.

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Anthropomorphic robots will gradually become a vital part of our daily life. To successfully perform various tasks these robots require reliable locomotion control algorithms, which could guarantee dynamic balance of the robot at every moment. Our study is focused on creating effective humanlike walking for a biped robot and a novel human-size Russian robot AR-601M is utilized for this research. In this paper we present AR-601M robot, overview existing approaches for locomotion control of a biped robot, and present current state of our study.

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This paper proposes a leg mechanism that has 2 rotational inputs. These inputs have no limitation of an angle. The trajectory of its foot can be modulated by changing the phase of the two inputs. The mechanism consists of 11 links. We show its structure, kinematics, and workspace, and developed a prototype.

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This paper reports a new toe of four-legged robot' legs using a spring and the results of measurement of energy consumption in the trotting gait. It is not easy for our four-legged robot to walk. One of reasons is the impacts at the touch down, which reduces the stability of body posture. Thus, a new toe with a spring was redesigned and built, which would reduce the impact force. We installed the new toes into the robot and succeeded in its trotting gait. We measured the energy cost (energy consumption per unit distance) in trotting gait. As a result, we found that in trotting gait, the energy cost decreased when the locomotion speed increase. We concluded that these phenomena may be caused by decreasing the number of steps, which is caused by increasing step length.

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In this paper I will introduce six-legged walking robot consists of g degrees of freedom. This robot is constituted by a servo motor, the total weight is 614[g]. For moving the general feet in any position in the three dimensional space in the walking robot consists of one leg 3 degrees of freedom. The robot consists of three frames, it is a reduced freedom configuration. Less restriction of the ground point selection than reduced freedom robot consisting of two conventional frames, it is possible to perform the turning and straight. Overall degrees of freedom for configuring the robot can improve the loading performance, and has a design achieve energy saving.

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In this paper, we focus on the information of ground reaction force to generate locomotion of a tripedal walking robot 'Martian III'. Our previous works have indicated that the phase difference among the legs is a dominant factor for the locomotion of Martian III. In order to generate more diverse locomotion like animal, it is necessary to use feedback information on the environment. Thus, we add feedback term by utilizing the ground reaction force to national frequency of the periodic input of legs, and verified that generate the phase difference between each leg by robot.

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Time optimal control method for quadruped walking robots has been developed and installed into a practical robot system. The fastest trot walk and the trajectory of swing legs have already been obtained by our previous study. In this study, we designed velocity trajectories of the body and swing legs. Then, the design method of velocity trajectory that can accelerate to maximum speed in the shortest time and can decelerate to stop in the shortest time is established by combining velocity trajectory of the acceleration part and deceleration part of the body. Finally, we verified the simulation results.

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This study deals with a quadruped wall walking robot with four legs and four suction pads at the leg tips. Each leg is composed of three links connected by rotational joints and the robot is capable of climbing a step and moving between difference surfaces, i.e. from a floor to a wall or from a wall to a ceiling. However, such a leg mechanism easily causes the leg tip position error and generates an unexpected reaction force from a wall; thereby the wall walking robot easily falls from a wall. In this paper, distance measurement between a wall and a leg tip makes it possible that the robot can walk stably on a wall with any slope angle.

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Robot that mimics the general biological limb has actuator in only each joint. However, organisms have Bi-articular muscle that moving simultaneously two joint. When viewed from the perspective of biology, Bi-articular muscle does not have not anti-gravity. But, when viewed from the perspective of robotics, it has very high anti-gravity. Bi-articular muscle there is a redundancy. Thus torque cannot be determined uniquely. Therefore, it is necessary to distribute the torque to determine the conditions for each motor. This paper has proposed torque distributor using the bi-articular muscles to gravity compensation for Quadruped walking robot. By using proposed torque distributor and Bi-articular muscles, it is possible to reduce the eneru when walking.

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Multi-Legged Movement Mechanism is strong against turning over. It also has an ability to keep moving on an uneven terrain even if it is entirely sunk under sediments such as mud or snow. However, implementation of the gait by links is difficult and complex for a smaller and faster robot. Another problem is that there is no method to change its direction. This study is intending to overcome these problems by the following approaches: (1) downsizing the size by realizing the gait by link free mechanism, and (2) introducing direction change method by acceleration and deceleration. Also, one of the major problem is how to design a gait for a various configurations that have legs attached at all sides. To this end, we propose a design method which is based on a graph coloring problem of the theory of graphs.

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A water surface running is a machine that runs along the water surface like a basilisk lizard. The machine supports its body weight by slapping its feet on the water surface and stroking them into the water. This report presents the design of its leg mechanism with variable stiffness mechanism. To realize the water surface running machine, it is required to generate large upward force when the machine slaps and strokes its foot into the water and minimize downward force when the machine pulls its foot out of the water. We proposed the leg mechanism to generate large upward force and minimize downward force. To generate large upward force, the foot impacts on the water surface in the vertical downward direction with high stiffness and to minimize downward force, the foot is pulled out of the water with low stiffness. And we propose and designed leg mechanism generation this foot motion we designed an experimental apparatus of water surface running machine.

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The paper deals with a free gait generation algorithm for the straight line motion of a multi-legged walking robot in rough terrain. This method employs a heuristic graph search procedure because of the huge searching space of legged locomotion. In advance, deadlock situation and inefficiencies are avoided. This algorithm generates only statically stable walking of 6 legs robot. Footholds, stability constraint and kinematic constraint are considered when gaits are generated. This method does not consider the choice of the leg grounding point. The choice of leg grounding point is consider in other method. The paper includes verification experiments in a simulator.

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Many moving robots to search in uneven ground have been developed, carrying robot in uneven ground is dangerous. Operators may injure during carrying in. If robots are able to throw in uneven ground, it is safety and easy to carry uneven ground. In this study, we proposed carrying to uneven ground by throwing the robot to avoid carrying at the time of the risk of robot to uneven ground. Thus, we developed quadruped robot with a spherical shell. In this paper, we report the realization of operations such as gait and rotational motion using a spherical shell.

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In a confined space, such as in-pipe environment, where humans cannot go, the implementation and repair work by robot is expected. By equipping robots which have special movement mechanisms with sensors such as a camera, researchers have been able to realize inspection work in such environments. For a robot to realize repair work, functionality via a robot arm is necessary. The limb mechanism robot "ASTERISK" is a multi-legged robot which has 6 "limbs". A limb is defined as a leg which integrates a working mechanism and movement mechanism. If this robot has the ability to move in a confined space, that would also mean it is able to do basic repair work. In this paper, we use an environment made up of two walls, and proposed two gaits for moving in such an environment, as well as an power efficiency model which cuts the electric power consumption.

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Many robots for purpose of exploring disaster sites have been developed. However, carrying robots to disaster sites is dangerous. If it can be thrown into the disaster sites, operators are safe. The purpose of this study is development of durable robots. Thus, we developed quadruped robot with spherical shell. We have added a jumping function to climb over steps to it and Calculation of it by air cylinder for the realization. We were confirmed the storage and deployment of legs operation.

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An anthropomorphic lower leg mechanism that varies the torque transmission ratio depending on an engaged motion of the knee and the ankle is presented. A couple of cascaded four-bar links encodes the preferred transmission property, which should be high when the leg is in stance phase and low when in swing phase. A prototype showed that the required property can be achieved by a real mechanism.

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Legged locomotion is suitable to move on uneven terrain. However, advantages of legged robots have not been achieved yet. In this study, a relationship between combinations of the joints and generated force or torque will be discussed. Legs with four joints were considered. These legs have a possibility to adapt a rough terrain because of their redundancy. Redundant joint can change the direction of maximum force without changing force distribution. After several considerations, three legs out of 81 combinations are examined to simulate. We reported the effective DOF structure configuration which can walk on large-scaled uneven terrain than force analysis.

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Electromagnetic motors are useful actuators for robots due to good controllability and low cost. But, usually electromagnetic motors together with reducers of high reduction ratio are used to actuate robots. It is difficult to realize creature-like dynamic motions such as fast running, high jumping, by the robots due to low backdrivability of joints. To solve the problem, a robot with leg mechanisms consisting of spring and damper inspired by bi-articular muscle-tendon complex of animals, has been developed. As the result of experiments for dynamic motion, trot running at a speed of 3.5 kilometers per hour and forward jump about 1 body length per jump have been realized by the robot.

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Hyper redundant manipulators are interesting solutions to conduct manipulation operations in complex environments such as nuclear plants and chemical plants. These types of manipulators can be used in complex environment because -of the ability to manipulate objects from multiple directions. However the main drawback of these manipulators is the increased weight due to large number of actuators. Biomimetic-manipulators have been developed to solve the above problem. They imitate biological systems in which a large number of joints are driven by cooperation of muscles. This approach reduces the number of actuators required. However, the weight of the whole system is not reduced due to the need of an air compressor. In this paper we present an initial prototype of a lightweight, joint-less manipulator using springs. While this prototype light in weight, it cannot achieve complex operations like bending only the tip. To solve this problem, we developed a second prototype manipulator with movement restriction mechanism using a solder. Experiments were a conducted to evaluate its movement restriction capability.

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This study successfully fabricated a dimpled cellular tissue by using the interface between the gas and liquid of air bubbles generated on cell suspension. The bubbles were structured with a hexagonal pattern and its interface was named as structured interface. Ten million of cells were once formed with dimpled surface within 2-h cultivation with the structured interface. The cells were excluded from the structured interface and accumulated into the gap among bubbles. This study called the formation and accumulation of cells by the structured interface "inverted-scaffold effect." The dimpled cellular tissue might be a possible solution to improve the cellular viability of thick tissue in the initial stage of cell culture.

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We have successfully developed novel processing equipment based on the combined of cavitation and plasma irradiation. This technique uses the strong points of the powerful ablation of cavitation as well as plasma irradiation. The novelty of the technique enable to process not only conductive material but also non-conductive material such as polymer, CFRP(carbon fiber reinforced plastic) and copper plate, which is unlike conventional wire electric discharge machine. Also, the directional transportation of bubbles provides positioning accuracy of micro-processing. The structure of the plasma-cavitation pencil cutter is low cost and very simple structure. This technology contributes to effective processing of wide range of materials such as metal plate, polymer, carbon-fiber and biomaterials.

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This paper presents fundamental evaluation of needle-free bubble injector which has been developed recently. The needle-free bubble injector is mainly composed of an inner glass electrode surrounded by outer reagent-supply shell. Cavitation of a single bubble occurs at the tip of inner electrode and perforates biological tissue immediately when the voltage is applied to the electrode. Subsequently, the bubble is launched at high speed from the electrode transporting reagent into the biological tissue. This device can be used under liquid as well as under air environment. This novel device is applicable to various typs of cells such as animal cell or plant cell with minimally invasiveness. This method will contribute to wide range of biological applications such as gene therapy and gene transformations.

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Inkjet printing and prototyping system have a good compatibility for a rapid fabrication and an easy design. We propose a prototyping system which uses a commercially available inkjet printer for printing circuits and structures on the printed robot. A gripper robot with a developed paper actuator was fabricated using inkjet printer. This paper show the printing method and experimental results.

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An actuator to get the harmony of a human being and the machine includes a dielectric elastomer actuator. Because an actuator is flexible, it is said that the movement that was thought that it is impossible until now enabled. The dielectric elastomer actuators have flexible electrodes to the both sides of the elastomer. These actuators are driven by the high voltage. Previous studies, the electrodes of the actuator were made of the acrylic polymer and carbon particles. However, the deformation of the elastomer actuator was small. In this study, we created and investigated the flexible electrodes made from carbon nanotubes and carbon particles.

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We have succeeded in generation of micro-vortex ring using cavitation phenomena and high speed micro-bubbles laden jet in microfluidic enviromnent. First of all, the relatively large mother bubble is prepared at the tip of the probe by electrically driven bubble generator. As soon as after the mother bubble is collapsed due to by the cavitation, a strong jet is produced which derive the circulating motion in the bubble, and vortex rings are successfully produced eventually. The fluidic force produced by vortex ring is measured by cantilever, and cleaning effect on a wall by vortex ring is also evaluated. These vortex rings has potential to produce share stress to clean the microchannel wall in a closed space which tend to be difficult to be cleaned, and also strong mixing effect is expected to provide efficient reaction which contribute to the field of chemical engineering.

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