A platform for simulating endovascular intervention procedure for evaluating surgical robots and instruments, is presented. An in vitro patient-specific blood vessel model which precisely reproduces the soft membranous configuration of artery and its physical properties (e.g. elastic modulus and friction coefficient) is constructed. And IVR (interventional radilogy) surgical modality, such as DSA (digital subtraction angiography) and Road Map technique, which is peculiar to endovascular intervention is reproduced. Consequently, we constructed conprehensive surgical simulation platform for endovascular intervention.

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An in Vitro patient-specific vasculature model of human arterial system, for simulating endovascular intervention for evaluating surgical instruments and preliminary simulating surgical procedures, is presented. Presented vasculature model precisely reproduce the thin membranous configuration artery, in addition to its physical characteristic such as elastic modulus and friction coefficient. Applying photoelastic method, proposed simulator visualize stress condition on vascular wall arisen from surgical operations and blood streaming, allowing very detailed practical evaluation for respective purposes.

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Ultrasonically Activated Device (USAD) can treat tissues with coagulation and cutting ability, but it has large pitfalls in surgical procedure due to its straight shape. This sometimes makes surgeons to use this device from undesirable approach that might cause complications in surgery. We developed new method to mount small USAD unit on the tip of surgical manipulator with 2 bending DOF to realize safe approaches to target tissues, and verify the characteristics of a USAD.

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In recent years, surgical accidents increase with the increase of minimally invasive surgery such as laparoscopic surgery. Today most of the remote surgical robots that were developed use actuators such as motors, have the risk of producing excessive force. In this research, we proposed a safety operation tactics for remote surgical robot. This tactics consists of "Setting system of safety operation space" and "Variable compliance system". The former can prevent the collision between the forceps and the organs which is caused by the operation error by setting the operation space beforehand. The latter can reduce the collision force between the forceps and the organs which is caused not only by the operation error but also the movement of the organs by changing the compliance of the joints. These tactics were developed in our remote laparoscopic surgical robot "Hyper Finger" and we have tested and proven its effectiveness.

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The authors have been developing a surgical robotic system for scaphoid fracture reduction. The system consists of a surgical planning software to plan the position and orientation of wire insertions and a robot to assist the wire positioning. For achieving the robotic surgery, registration process is required. One of promising methods for registration is the method which employs a 3D deformable model of bone surface and deforms it by using several 2D X-ray images. In this paper, the authors proposed a fast method of X-ray fluoroscopic position measurement for bones. The authors evaluated the computation time and discussed by compared with a conventional method.

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Toolpath generation and optimization is considered to be a challenging problem in the minimally invasive orthropedic surgery with a milling robot. The objective of this paper is to minimize the collision of the cutting tool with soft tissues. A novel approach of toolpath generation and optimization is proposed. A redundant axis is implemented to avoid collision with the robot. Some important components are modeled based on the physical requirements. A geometric optimization approach based on the model is proposed to improve the toolpath. Software is developed for this application.

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The Roller-Walk is one of methods for locomotion of walking robots. It requires only passive wheel(s) on each of legs, and periodic motions of legs generates driving force. Successful results were shown in quadruped robot, and some trials had also been carried out on biped robot. The biped roller-walk had a problem in following trajectories because its 'skate' tends to go straight while trajectory curves. This paper proposed one of successful method for biped roller-walk. The robot use a special type of trucks whose curvature can be changed only by inclining the body of the truck. The experiments showed effectiveness of our mechanism in roller-walk on straight, right turn, and left turn trajectories.

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In this study, we propose a simple hopping mechanism using vibration of a two-degrees-of-freedom system for a wheel-based hopping robot. The robot, consisting of two bodies connected by spring and a wire, hops by releasing stored energy in the springs and quickly travels using wheels mounted in its lower body. The trajectories of the bodies during hopping change in accordance with the design parameters such as the mass of lower body and the mass of upper body and initial contraction of the spring, the spring constant. This property allows fast movement, hopping up and down steps, leaping over a cable and soft landing. In this paper, the design parameters that perform soft-landing are investigated by a genetic algorithm.

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In this study, we propose a simple hopping mechanism using the vibration of a 2-DOF system to develop a fast wheel-based stair-climbing and obstacle-leaping robot. The robot consists of two bodies connected by springs and a wire and hops by releasing stored energy in the springs. The trajectories of the bodies during hopping change in accordance with the design parameters. In this paper, we demonstrate fast move, hopping on a step, leaping-over of a cable and their soft-landings using this characteristics.

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Generally, the transmission system has a supporting actuator for changing the reduction ratio. Therefore, the transmission system becomes complex, large, and heavy. In this research, we propose a load-sensitive dual states transmission with a Two-Way clutch. This transmission changes the reduction ratio responding to load torque without a supporting actuator. If the load torque is low, the reduction ratio sets low and this transmission outputs high speed-low torque rotation. If the load torque is high, the reduction ratio changes higher one and this transmission outputs low speed-high torque rotation. We developed the crawler actuating unit with proposed transmission and confirmed basic performance.

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Tethers improve the mobility of robots on the irregular terrains. To realize this moving system, we developed the casting hook that is connected to the tether, and can be anchored to some object around the robot. It has only one claw differently from foregoing hook for the purpose of reducing weight and extending the length of claw. It also needs to be released after being used, so we equipped two types of locking mechanism, electric and pneumatic type. We did experiments of its casting, anchoring, and releasing, and confirmed their performance.

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In this paper, we discuss about locomotion of snake-like robots on uneven terrain. In recent research some snake-like robots have been developed which have ability to advance on uneven terrain, but the control has not been established. In this paper we propose a control method using a touch sensor located on the head of robots, and verify the effectiveness of propose method by experiments. We think the result of this paper will contribute to the study to put snake-like robots to practical use.

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There're a various networks which can represent bipartite graph in the real world. Most of the unipartite graph clustering methods have been researched but few of the bipartite graph. The bipartite graph clustering methods have been implemented by the unipartite folding. But this approach results in lack of link information, and existing approaches have a large computation orders. In this paper, we propose the bipartite clustering by TSP solution. We propose three cost function definitions with vertex adjacency vectors. Then, we apply the solution to computer-generated graphs with Local Clustering Organization(LCO). As results of the experiment, we obtained clusters by cutting high cost threshold, and we found that the cost function based on cosine construct better clusters.

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This study focuses on emergence of heterogeneous personal characteristics in a society. Such characteristics can be observed in not only human but also many organism, and deeply effect on personal making-decision and action. This paper treats with a swarm-agent model in order to examine how and what heterogeneous personal characteristics come out. A pursuit problem is set for the swarm-agent to efficiently capture a run-away object in cooperation. An artificial neural network (ANN) is adopted for the swarm-agent intelligence and evolutionary computation is applied to figure out the problem. After numerical simulations, it is observed that swarm parameters, determining agents' characteristics, for each agent are differently developed.

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In the action determination of the group which uses an agent as an element, an interaction is complicated. In addition, it is difficult to treat time series. Furthermore, it becomes more difficult to treat, if the number of agents increases or environment becomes complicated. In order to solve this phenomenon, group action is observed by using ε-greedy policy as one approach. And the possibility of this method is considered.

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In this paper, design and building of a prototype omnidirectional wheelchair are presented. On the design process of the prototype, fundamental study and experimental data using a small robotic vehicle were used to determine wheel diameter, gear reduction ratio, motor capacity, etc. for satisfying the specifications required for the 4WD omnidirectional wheelchair. Prototype wheelchair equips with drive wheels 275mm in diameter, driven by two 300W motors via power transmissions which reduction ratio is 25. A chair mounted on the 4WD mobile platform is rotated by 200W motor independent from wheel drive. The prototype wheelchair is expected to surmount a 100mm step with a human operator, whose weight is 100kg at maximum.

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The system that stabilizes with an optical mouse sensor for PC and can run to all azimuth movement robot with slip the wheel a large, difficult Omni wheel to control as a moved distance sensor in this research is developed. It can be said to all azimuth movement mechanism a suitable sensor also because the optical mouse sensor is a noncontact system sensor, and nonholonomic sensor.Moreover, making to the conserve wiring, and simplifying the entire system become possible by using generality and high USB in the connection of the optical mouse sensor.

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ACV(Air Cushion Vehicle)that can move without touching the land is effective as a mode of transportation in the place where unleveled land and transport link that is divided into parts due to the disaster. However, ACV is hardly used at present because a skilled control technique is necessary. Therefore, we can use ACV effectively for transportation system in the stricken area and unleveled land. It is necessary to get localization in real time so that ACV can autonomously move. In this research, it aims at an autonomous movement of ACV and an using visual odometry as localization. Visual odometry is suitable for the localization of ACV because Visual odometry should not maintain the infrastructure. In this paper, We developed the ACV which moves autonomously and confirmed the movement in the experiment.

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In this research, a pipe inspection robot adaptive to pipe diameter was developed. Using the sinusoidal wave drive, the robot forms sinusoidal waves and obtains moving force by gripping pipe walls. The robot consists of thirteen intelligent actuators. Each intelligent actuator is composed of a DC motor and a micro servo circuit and a pair of bevel gears. It leads to decreasing the number of the wirings, high performances achieved by distributed processing and high tolerance for electrical noises. In this paper, a new servo circuit for higher control performances and a rotational mechanism for control the robot's posture are shown. On the new micro servo circuit, a PSoC (Programmable System on Chip) and a motor driver are mounted. The mechanism rotates around the pipe axis. The robot can propel itself in three dimensional pipes. The results show the potential of this system.

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In this paper, we propose and develop the stretcher robot which picks up and takes out the victim using crawler in a robot's upper side and object for a drive, respectively, without using people hand. For the composition which three small robots connect, operation corresponding to on-site environment can be performed. By developing the method of conveying victims to a safe place by the number of rescuers fewer than before, reduction of the staffs who are needed for rescue activities, and labor and burden of rescuers can be reduced. Furthermore, it can expect that the whole rescue activity can be performed efficiently in order that the rescuers who became a surplus may perform search activities

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In this study, roller skates movement was added on 2-Legs robot as a new moving method. In this method, 2-Legs robot moves like as roller skating using the kinetic energy which was generated by kick motion. A test robot (height 39cm, weight 1.9kg) was developed and roller skates movement was succeeded. The robot moved 43cm at 1.4sec.

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This paper proposes the new suction system by wet condition for wall climbing robot. Liquid between the suction cup and adsorbed surface makes the friction reduced. Additionally, it keeps the sealing performance higher than the case of dry condition. This paper reports the basic experiments to test the performance of new adsorb system which consists of wet adsorb system.

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A query to use at the time of a web search is important to control a result greatly, but the choice tends to depend on perception and experience, and it is difficult for a beginner's user to get the result that is an ideal. As one of the solutions, there is a search by the sensitivity word that the use is possible by human feelings intuitively soon. I limit it to a new car search, but build a new car search support system using sensitivity word as a search item. In this study, I try characteristic extraction of a design based on feelings map provided by Semantic Differential method.

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Recently, various fields pay attention to e-leaming system. These contents have been complicated from the static one to the dynamic one. It is similar in guitar e-leaming system. The guitar education and the education of music obtain detailed instmctions by studying under someone professional. And, DVD on the market, CD, and the teaching material of this so on are used when studying it by oneself Howevm, there is no room that goes to the classroom, and the motivation might not occur in the teaching materials. Therefore, it is necessaiy to apply the focus to contents used for the system first of all. This contents are specific perfonnance technologies that are called "Power Code". The reason to choose the power code is that the composition of the sound is a simple, and a significant one for the guitar training besides. In this research, we propose a guitar e-leaming system using contents paid attention to camera angle.

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Recent years, various image informations exist on Web. It is possible a virtual experience of like going to the strange land by using this. It is useful for the person who wants to be searching for the land beforehand by the person, the travel, and the official business, and where it cannot go to the land for bodying it. It proposes the virtual experience tour in route to the destination using digital contents including the sight scenery based on digital archives information that is not made of limits the purpose. The system is constructed by using Google Maps API, and considered of utility.

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Spatial key-framing is one of the methods for generating animation of CG characters, in which a control point corresponding to a full body posture is defined in a workspace, and animation is generated by moving the control point in the workspace. In this paper, we try to develop a CG character animation by generating a trajectory of the control point semi-automatically interacting with a user. We introduce a nonlinear oscillator (van der Pol equation) for the trajectory generation, and evaluate how much it can create a variety of motion and how much it can reflect a user intention, through a computer simulation.

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We describe the development of a journalist robot system, which generates articles by searching for news in the real world. Our system repeats the steps: (1) autonomous exploration (2) recording of news, and (3) generation of articles. We characterize events with two values: "anormality" and "relevance" to the user. During the exploration step, images are evaluated using these values. If an interesting event is detected, the robot approaches it to collect additional information. The system then labels the images, and generates a description from the labels. Experiments show the ability of our system to find news-like phenomena and describe images with words.

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In order that robots coexist and work with human in actual environments, a robot needs to handle a task immediately whenever human asks it. At the thought of the task we want robots to do, quick grasp is one of important tasks. Therefore we propose "responsive grasp," that is generated responsively through relationship between sensors and motors. The responsive grasp consists of learning of probabilistic networks as knowledge model, and generating grasping behavior through the knowledge model. In addition, we classify and abstract learning objects in order to cope with unknown objects. We constructed the responsive grasping system, and verified its feasibility by simulation.

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We propose a novel method for learning dynamic multi-DOF motion with fewer trials and less pre-specified knowledge about the tasks. It is a combination of a motion representation called Virtual Goal Switching Pattern, and a search method consisting of initial random exploration followed by hill-climbing. The Virtual Goal Switching Pattern consists of a controller, some phases and goal-postures for each phase. Both of the intervals of the phases and the goal-posture parameters are searched. This method was applied to 4 learning tasks: a targeted throwing motion with a 3-link arm, a jumping motion, a Roll-and-Rise motion, and a throwing motion with a bendable arm. In these experiments, dynamic multi-DOF motions were acquired quickly (less than 1000 trials). Several interesting related phenomena are also observed.

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This paper proposes the control and the learning method for a manipulator based on compound control. Compound control is the novel concept of biomimetic control and learning scheme. The most important feature for controls of living things is that controls concepts of simple and homogeneous elements and its networks. In this paper, compound control is applied to a redundant manipulator control. The hierarchical network of calculation elements is used to learn the desired angles and controllers of all joints using the position of endefector and the desired position of endefector. The simulation and experiment results show the effective of proposal method.

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Compound control is the bio-mimetic control and learning method. In order to learn based on compound control, feedback ioop in environment is required. Image is the most important environment sensor for living beings. Image processing and behavior control based on compound control is the important to generate various kinds of behaviors. This paper presents an initial network, which is one of the most important element compound control, for image processing based on compound control. This initial network is composed of three layers. Calculation elements corresponding to a retina are distributed to 2 dimensional array. OKR, one of the ocular motions, is realized by using the proposal initial network.

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This paper proposes a motion generation method in unknown environments. Living environments for human beings is complicated for human-friendly robots. Robot designer can't prepare complete motions beforehand. There are some previous researches to acquire new suitable motion for each environment. It isn't easy to acquire new suitable motion from scratch. In the proposed method, new motion is generated based on motion designed or acquired in another environment. Generated motion adjusts for each environment by referring sensor values while moving. The proposed mothod is applied to a walking motion of four-legged robot and experimental results show the motion for an environment is adjusted to another environment.

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Recently many robots have been developed. Robots' behaviors are described using their joint angles depended on their own architecture. So the behaviors that a certain robot has can't be accomplished on another architecture. In this paper, we propose posture description technique to inherit robots behaviors. Proposed technique describes robots' behaviors using position features that isn't depended on their architecture. When the architecture of the robot has changed such as joint failure, the robot can use their held behaviors according to remap new posture to corresponding previous position feature. Experimental results show the ability of the proposed technique to accede to robot behaviors between another joint range robots.

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Component based decentralized cooperative control system has been discussed for improving operating technology of multi- jointed redundant manipulator as well as the principle and basic structure of control system. The system consists of a set of components. The component is a basic motion control system to make control of driving unit corresponding to each manipulator part based on the principle of local kinematics. The motion of manipulator is tailared by cooperation base on information interchange in terms of the local control output of components. The control of various types of manipulator with dynamic reconfiguration is enable it without reconfiguration of control system. This paper deals with a principle of local inverse and forward kinematics for revolute and prismatic joint, and position and trajectory control of end-effector for complicated structure manipulator in which revolute and prismatic joints are mixed.

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The toolkit is developed to support system developers for developing distributed application systems composed of a set of software components in a network computation environment which consists of Personal Computer, Engineering Work Station, Computerized Controller, and so on connected by LAN or Wave LAN. The software-tool provides Inter-components Communication, Remote Procedure Call, Components Migration/Replication, and Dynamic Components Binding/Unbinding to application systems as well as network transparency. The configuration and reconfiguration capabilities of application systems can be improved by applying these functions provided by this toolkit, and also high efficiency is expected to develop of distributed application systems. This paper describes a tool kit and a general idea of a process to develop a distributed application system by using the thing which developed and soccer simulation and a traffic simulation.

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We tackle a Fish-Catching task under a visual feedback hand-eye system with catching net. The fishes change escaping trajectory or speed up when being threatened as the net attached at hand approaches to them. Furthermore, as the time of tracking and catching process flows, the fish can somewhat get accustomed to the hand motion pattern and gradually find out new strategies on how to escape from the bothering net. For example, the fish can swim slowly along the pooi edge where the net is forbidden to enter or keep a reasonable distance from the net as if it konws the visual servoing system bears steady state error by constant speed escaping. For the sake of such innate ability being widely existed in animal's behavior, the catching operation becomes tough and some effective intelligent method needs to be conceived to go beyond the fish's intelligence. The purpose of this research is to construct intelligent system to be able to exceed the fish's intelligence to survive. Then we embed chaotic motion into the hand motion of robot, and we have shown the chaotic net motion can overcome the fish escaping strategies.

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This paper deals with a concept that effective robotic function emerges from not only "intelligence" but also the balance of "intelligence" and "morphology" with physical interaction in the environment through the task. In this paper, the "morphology" of a robot is represented by the arrangement of two visual sensors and the "intelligence" is described as a decision tree of sensor inputs and motor outputs. Both of "morphology" and "intelligence" are automatically generated and evolved by genetic programming (GP) for a task of maintaining a certain distance between the robot and an object. The result shows that noise existing during a translation process from a phenotype to genotype doubles the incidence of symmetry in "Intelligence", i.e., a state-action coordination and an evolutionary robotic system with symmetry in "Intelligences" accomplishes a given task ever real world, because it has high robustness.

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An evolutionary design is suitable to perform optimization of both the morphology and controller of simulated robots for adaptive locomotion. However, the simulated robots do not necessarily achieve in real because the reality gap impedes. Therefore, we purpose to develop an evolutionary design system closing the reality gap by exploit morph-functionality to evaluation of the evolutionary design. Especially, in this paper, we use a three-link locomotion robot to investigate the proposal method.

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With soft exterior and tactiles, humanoid robots will be more adaptive to contact with daily environment or with self body, and will have closer relation with surroundings. But, such close interaction causes complicated contacts, and rule of tactile feedback to motion can hardly be derived with analytic approach. This paper will show that a tactile feedback rule in a rolling-over motion (as an example of close interaction mentioned above) of the baby sized humanoid can be automatically acquired with simulation based evolutionary robotics approach. At last, the acquired feedback rule is tested using real robot.

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Recently, as robotics has been developed, it is expected that robots are workforce taking place of people. Conventionally, rules for controlling the robots are designed by a designer, but under unknown environment with various uncertainties, it is difficult to design the rules previously. Therefore, there are many researches on controlling autonomous robots with learning abilities, especially reinforcement learning attracts attention. Reinforcement learning largely depends on parameters. Accordingly, it is necessary to develop an algorithm which can set parameters autonomously according to the state of the environment and the advance condition of learning while learning. In this research, it aims at developing a new algorithm controlling the parameters based on only reward information while learning.

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We have been developing a reinforcement learning technique called BRL as an approach to autonomous specialization, a new concept for cooperative multi-robot systems. BRL has the mechanism for segmenting continuous state and action spaces autonomously. Also, we have two types of extended BRL. The first one is that the state space is covered with redundant rules that avoid rule deletion to overcome the over-fitting problem. The second one is that, instead of generating a random action when a robot encounters an unknown situation, an action is calculated as the linear interpolation among the rules that have high similarity to the current sensory input. BRL with both extensions is examined by arm-type autonomous robots, the task of which is lifting an object without tilting it. The experiments conducted illustrate the high incremental learning performance of the proposed method by developing various types of cooperative behavior as a result of autonomous specialization.

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This paper addresses an autonomous space robot for a truss structure assembly using some reinforcement learning. It is difficult for a space robot to achieve a task on contact with the real environment, because of the error between the real environment and the model of controller. In order to solve the problem, we propose an approach that a space robot autonomously obtains proficient and robust skills against error of the model to achieve a task. Numerical simulations and experiments show that the proposed method is useful in the real environment.

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Being inspired by the existence of the small world networks in the neural net, we designed new structures of an artificial neural network and compare them with ones of conventional neural networks from a viewpoint of learning. We adopt the evolutionary computation for assigning proper weights to synapses. A learning test problem is given that a small robot located at the corner in a square field reaches the light source as fast as it can drive. Results in simulation shows that a small robot with a structure of small world networks in the nerves system can reach the light source faster than any other structures.

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Employing a learning system in which the "actor-critic' reinforcement learning method and a Gauss-sigmoid neural network are combined, a high performance learning system can be built due to the combination of the autonomy for reinforcement learning and the generalization capability for neural networks. Much time is needed when the conventional reinforcement learning method is used in order to train a robot with huge number of states such as our 1-legged hopping robot with 3-DOF. In this study, based on a simulation study for a wheel type inverted pendulum, we examined a few learning techniques different from conventional methods from the viewpoint of the improvement of learning speed. The obtained result shows that the increase of the number of modification steps as for connection strengths in neural networks is very effective for the decrease of learning cost.

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This paper presents a Machine Learning Method suitable for actual environments and treats Collision Avoidance Problem for multiple autonomous mobile robots as a case study.It is necessary that all autonomous mobile robots equip collision avoidance system as a function of movinig task commonly.Therefore, the ability of collision avoidance independently with moving objects is indispensable and should not be depending on devices constructing robots.The purpose is to emerge traffic rules that heterogeneous robots can avoid one onother with communicating only simple information.Using Reinforcement Learning suitable for uncertainty environment, the experiment was conducted in both distinctive and simple settings and gave some good results that collision avoidance actions emerged.In addition to, this paper shows stability of presented method by discribing the deference of performance in respect to the number of state partition which is one of the important parameters.

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A micro reactor has been attracting an attention to enable construction of high speed and high efficiency chemical process. The purpose of my work was to develop a micro reactor system with an active fluid control device. The active micro reactor system with outer dimensions of 148 x 105 mm2 was developed comprising two micro pumps, a micro mixer, an active micro valve and a reactor plate made with silicone rubber. A reactor plate connects an active fluid control device and forms a channel. A channel of a reactor plate is formed with various shapes in correspondence with a chemical reaction. The system is controlled with an exclusive controller. The mixing of a micro mixer was experimented on with the water which colored red and yellow. As a result, the mixing effect with a micro mixer was confirmed.

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Built-in, disposable micropumps are key devices for biochip technology. In this study, we propose an all-polymer built-in disk micropump driven by light. This micropump consists of a disk rotor and a horseshoe microchannel. In the disk micropump, continuous flow is generated by rotating the single disk rotor in the horseshoe microchannel. The shuftiess disk rotor is successfully driven by synchronized laser scanning. We simulated the flow in the horseshoe microchannel by Finite Element Method (FEM) and optimized the channel shape. Both the rotor and the microchannel were fabricated by using two-photon microstereolithography that can produce all-polymer 3D microstructures with lOOnm resolution. This micropump enables flow control on the order of pL/min. This ultra-low flow control provides high integration and miniaturization of micro-total-analysis systems.

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Four microvalves consisting of several hydrophobic and hydrophilic channels with no mechanically movable parts were integrated on a single Si wafer, and were driven simultaneously by air pressure that was controlled using electro-pneumatic regulators. Each microvalve is opened by a pressure through its inlet channel, and is closed by a pressure through an air vent channel that is connected to all the microvalves. When air vent pressure was fixed to 10-20 kPa, all microvalves could be opened and closed independently by applying appropriate pressure through each inlet channel.

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This paper presents the dynamic characteristics of an electrostatic micropump with Au/poly-Si bimorph structure. Its performance is achieved by using several cantilevers connected in series and bending them repeatedly with electrostatic force. The fabricated micropump was tested by applying voltages with various frequencies and amplitudes, and its deflections were measured using a laser displacement meter and a CCD camera. The micropump could be driven in a low-conductive liquid such as silicone oil, and the relationship between applied voltage and cantilever deflection had large hysteresis. The maximum deflection of the micropump in the silicone oil was obtained at a frequency of up to 15 Hz, and was decreased when frequency was increased to more than 15 Hz.

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Here we propose a novel micro-magnetic actuator based on magnetotactic bacteria (MTB). MTB are known for their response to an external magnetic field. A chain of magnetic nanoparticles embedded in MTB acts as a compass to orient MTB according to the magnetic field lines. To develop the rotational actuator using MTB based on magnetic principles that performs rotation of the magnetic rotor, we considered the motion control of MTB by dielectrophoresis (DEP). In this paper, the motion control of MTB was demonstrated by DEP and pearl-chain formation that MTB attract each other along electric field line was confirmed. And applying an external magnetic field to chains of MTB, we observed the rotation of the chains. Therefore we apply the micro-magnetic actuator using MTB that transports microstructures by torque of chains as a microstirring, micropumping and microvalve.

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