This paper discusses the evaluation of cell mechanical impedance by using a μ-channel. Through experiments, we found that the velocity profile of a red blood cell passing through a μ-channel can be separated into two phases; one is in the entrance area of the channel where the velocity heavily changes, and the other is in the remaining area where the velocity is almost constant. By focusing on the area of constant velocity, the stiffness effect can be evaluated, while the viscosity can be evaluated by focusing on the cell behavior in the entrance area. In this report, we show experimental data under two different initial speeds of cells, and consider the effect of impedance precisely.

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A new concept of μ-cell fatigue test is proposed. By reciprocating a cell across the throat of a micro channel repeatedly, the dynamic deformation behavior of the cell is measured. We define a new index of fatigue characteristics of cells as the number of reciprocatory motion leading to a prescribed recovery ratio. The test system is composed of a piezoelectric (PZT) actuator, a high speed vision sensor and a micro channel with a throat. Preliminary experiments were conducted by using Red Blood Cells (RBCs). The result suggested that the activation level of a cell can be evaluated based on its fatigue characteristics.

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Construction of large tissues from cell aggregates is one of the promising methods for tissue engineering applications. Compared to spherical cell aggregates, non-spherical cell aggregates are more suitable as building blocks to be assembled into complex larger structures. In this study, we prepared Ca-alginate hydrogel plates with microchamber structures via micromolding using a mixed solution of sodium alginate (NaA) and propylene glycol alginate (PGA) to form toroidal cell aggregates composed of multiple cell types. In addition, the prepared toroidal cell aggregates were used to construct capillary-like tissue structures by stacking through thin wires.

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Micro contact printing (μCP) is often utilized for micro patterning of proteins to fabricate a co-culture system with the structure like a real tissue. To date, temperature-responsive culture dish becomes one of the most important device for regenerative medicine because a cell sheet is recovered from the culture dish by only lowering the temperature of culture dish. The recovered cell sheet is able to be replaced a damaged tissue. In this study, cell adhesion molecule, fibronectin, was patterned on the temperature-responsive culture dish by automated μCP system and two types of cells were co-cultured in the fibronectin-pattered culture dish.

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This study describes a cell-culture systemallowing culture cells to be exposed to an oxygen gradient condition, which was created with the diffusion of PDMS (Polydimethylsiloxane) from a micro channel at the bottom of a bleeding ground for cell culture. Hypoxia culture condition of tissue and stem cells have recently attracted attentions for formingtissue structure, imitatinghuman body, and analyzingthe differentiation of stem cells. The system composed of an oxygen gradient PDMS-chamber made with a micro-fabrication technology, and a hypoxia desiccator realized an oxygen density gradient from 0 to 159 mmHg in the surface of the chamber. Cells in the hypoxia region of chamber were stained with pimonidasole, a hypoxia marker, which was confirmed by an immunofluorescent technique. The proposed oxygen gradient system was able to be readily applicable to efficient and precise studies investigating of the tissue function or differentiation of stem cell.

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We propose a non-invasive ultrasound theragnostic system that tracks and follows movement in an affected area (kidney, in this study) while irradiating it with high-intensity focused ultrasound (HIFU). In this paper, a kidney motion model is proposed to estimate the kidney position for robust tracking and following of the target kidney. The experimental results show the effectiveness of the proposed kidney motion model and the proposed algorithm for robust servoing of the target kidney.

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Recently, a medical disparity in remote areas has been an emergent problem because of a shortage of doctors and the telemedicine approach has been strongly needed. In our laboratory, we have developed a "Telerobotic medical diagnosis system." This system will provide the primary care remotely for patients. In this research, we will develop a new diagnosis robot system based on passive safety design.

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Since ultrasonic diagnostic equipment is small and cheap compared to CT or MRI, 3D-information acquiring methods by ultrasound (US) are widely studied. For that purpose, identification of the spatial relationship between an US probe and a position measuring device is required. Many methods have been proposed, but there is little research taking into consideration the thickness of the cross-sectional image. In this study, we propose a cross-sectional image position identification method taking into account the section thickness. Additionally, we performed an experiment to assess the accuracy of our method. We observed that it is simple and accurate.

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Ultrasound is widely applied to clinical purpose as Echography and High-intensity focused ultrasound for ablation therapy. Also, we have studied micro bubble control in blood vessel using ultrasound for acoustic targeted drug delivery. These techniques require accurate position control of therapeutic ultrasound field based on ultrasound image information. Therefore, we proposed a robotic system to control a position of an ultrasound transducer for therapy based on ultrasound image information. The system consists of an ultrasound probe for image-capturing, an ultrasound transducer, a robot with the therapeutic transducer, positioning software and an optical tracking device to integrate the coordinates. The system enables the transducer follows to a US imaging probe based on a therapeutic plan. In this study, positioning and following control accuracy was evaluated. The results demonstrate the system has a potential for targeting the transducer based on intra-operative planning.

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In our daily life, there are many rheological objects like human tissues and human organs. FEM (Finite Element Method) is widely used in the numerical computation of rheological object deformation. Compared to another deformation method, FEM can simulate the deformation more accurate but takes longer computation time. Simulation of rheological object deformation is often required of real time processing in surgical simulation. To shorten the computation time, we apply GPGPU (General-Purpose computing on Graphics Processing Units) in the computation of rheological deformation. This computation mainly consists of matrix computation. Thus, we will implement matrix computation to GPGPU for real time computation.

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Capsule endoscope cannot carry out observation at a fixed point because it uses the intestinal peristalsis as a means of transportation. Therefore, in order to carry out observation at a fixed point with a capsule endoscope, a brake attached to the capsule endoscope is effective to stop it at the point. This paper proposes a helical expansion mechanism as a brake for capsule endoscope and develops a cable-driven brake mechanism. The helix expanded by pulling the cable pushes the intestine, which serves as brake. We show the performance of the helical expansion mechanism as a braking mechanism by experiment.

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For tissue engineering, it is very important to construct cell patterns and immobilize patterned cells inside certain structures. In this paper, we present a novel method of forming line pattern of yeast cells by dielectrophoresis (DEP) and immobilizing patterned cells by photo-crosslinkable resin. Microstructure embedding patterned yeast cells is on-chip fabricated. Several microelectrodes are fabricated by Indium Tin Oxides (ITO) for cell patterning by DEP. The two kinds of DEP responses of yeast cell (W303) and the experimental parameters are experimentally confirmed. Based on negative DEP phenomenon, cell traps generated by microelectrode are demonstrated. A cell trap matrix is fabricated and high speed cell pattering is performed. The experimental results show that the cell line patterns which contain hundreds of yeast cells can be formed by DEP within 1 second. On-chip fabrication method for arbitrary shapes of microstructures based on Poly Ethylene Glycol Diacrylate (PEG-DA) is reported. With the cell patterning by DEP and immobilizing by on-chip fabrication, microstructures embedding 3 lines of yeast cell are directly fabricated inside microfluidic chips, in PEG-DA and NaC1 solution.

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In this paper, we propose the on-chip capacitive force sensor for ultrahigh speed cellular force measurement. In order to apply the capacitive force sensor to microfluidic chip, on-chip force sensor utilizes the air-liquid interface due to isolate liquid form comb electrodes. We have designed and fabricated the capacitive force sensor with cell culture chamber as a kind of microchannel to the several pm order cell. Air-liquid interface between the force sensor tip and comb electrodes have achieved. As a result, we have succeeded in measurement of capacitance of on-chip force sensor as a function of displacement of probe tip in wet condition.

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Recent trends in tissue engineering have aimed at simulating the physiological environment in vitro. So many researchers try to generate much like body tissue constructs by bottom-up approaches in the field of tissue engineering. We proposed new 3D assembly techniques to fabricate a hollow tissue construct using by water transfer printing. And it enables us assembling three-dimensional multilayered tissues to curved surface easily. Also we discussed optimum geometry of development figures. Finally, we succeeded in assembling three-dimensional multilayered tissue into tubular construct by this method. The tissue consists of neonatal normal human dermal fibroblasts (NHDF). These artificial hollow tissues would be used for drug efficiency evaluation and operative training as in vitro simulators.

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This paper presents cellular force measurement in a microfuluidic chip. We employed magnetically driven on-chip probe with displacement reduction mechanism to obtain nanometric positioning of probe with mN order force. This mechanism utilizes the serially-connected springs with different stiffness and is driven by magnetic force. The standard deviation of displacement of probe tip was under 0.18 μm. Moreover we have succeeded in on-chip deformation of the 100 μm order cell. The manipulation power was estimated to 0.42 mN. We have succeeded in 100 nm order non-contact actuation of on-chip probe with a power of 0.1 mN order. Finally, we have demonstrated on-chip cellular force measurement.

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Stretchable temperature-responsive cell culture surfaces was newly prepared by grafting poly(N-isopropylacrylamide) (PIPAAm) on polydimethylsiloxane (PDMS) (PIPAAm-PDMS). The PIPAAm-PDMS at non-stretched state showed temperature-induced cell attachment and detachment properties similar to conventional PIPAAm-TCPS, while that at stretched state did temperature-induced cell attachment but slower detachment properties than that at non-stretched state. As expected, such slow detachment is due to decrease of PIPAAm thickness and PIPAAm graft density as well as increase of hydrophobic property induced by stretching procedure. This result also suggests that hydrophobicity of PIPAAm-PDMS surfaces is appropriately adjusted to target cells to be cultured by only stretching the surfaces.

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The establishment of methods for fabricating a 3-dimensional tissue structure in vitro is an important challenge in the field of regenerative medicine. Present tissue engineering is not sufficiently advanced to fabricate large tissue structures or organ structures which have a lot of cell constituents such as a liver. Therefore, various approaches to building 3-dimensional cell structures are currently being researched. In this paper, we propose a mesh-shape 3-dimensional structure, obtained by using alginate gel fiber which contains cells. We also try to make a mesh shape structure by using our developed system. By using the proposed system, we demonstrate that it is possible to fabricate mesh with various interval sizes and 2-layered mesh.

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In this paper, we build a nano-tool exchanger system (NTExS) for the analysis of cell high efficiency without breaking the sample chamber of Environmental-Scanning Electron Microscope (ESEM). The nano-tool exchanger system consists of mainly three parts, 1) nanotool attachment, 2) nanotool adapter, and 3) nanotool holder. Through the nanotool exchanger system, we can obtain that 1) it is possible to exchange nanotools without opening the sample chamber of ESEM and evacuating again, 2) it is not needed to exchange them manually, and 3) it is possible to use the different tools continuously.

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In medical field, medical equipment after the surgery, the person is doing the washing. As this problem, that it is hard work, and include health care workers to infection from medical equipment. As medical field needs, there are to ensure safety and reduce the burden of health care workers. Therefore, it is considered to be ideal medical equipment cleaning system without going through the human. In order to achieve manage the medical equipment, it automatically needs to be recognized the medical equipment. In this research, conduct research and development of systems for automatic recognition of medical imaging equipment. About the system, create CAD of full automatic processing system and simulate motion of it using the SMASH. In addition, the study of traceability is achieved by constructing the system of medical equipment management.

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One of medical issues of our country is not only increase of patient but also relative decrease of doctor by super-aging society. Diagnosis and Treatment support system is necessary to reduce the doctor's load. So, in this paper, we purpose the development of the diagnosis and treatment support system for Robotic-echography. It is needed to workings high accuracy, high-speed and workings by extending to the large range to some degree. Then, the link variable system that is used fuzzy inference has been constructed and its availability has been verified. And the model of 5 axis manipulator has been simulated with the system. Then, the simulated model has been designed with electric and pneumatic actuator.

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We have developed a made-to-order surgery support manipulator with a sensing function for the mechanical characteristics of internal organs that can be customized based on the maximum grasping force for each patient. The purpose of this study is to develop elasticity-sensing forceps using the phase difference of the stepper motor. We proposed a new gripper to measure automatically the elasticity defined as the spring constant K. We showed the measurement method and the system concept composed of a gripper and a display. We made two prototypes of the gripper: a bevel geared gripper with single jaw and a rack-and-pinion gripper of long axis with a pair of jaws. The display showed the five values using blocks. To evaluate the prototype, it was used to measure K for seven fresh in vitro dog organs. These results were compared with the value measured by a material testing machine.

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In this paper, a method for automatic identification of a surgical operation in endoscopic surgery and distinction of the singularity of the identified surgical operation is proposed. Surgical operation of ligation is divided into seven operations, and on the basis of the threshold criteria, a surgical operation is identified as one of them. Next, when the surgical operation is identified as a thread knotting, the operation of thread knotting is classified as either normal or singular using a self-organizing map. In addition, construction of a warning system to avoid medical errors by presenting detection of the singular operation to surgeon and to provide safe endoscopic surgery was executed.

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This research aims to realize the walking of bipedal robot on an uneven surface by using a novel foot sole mechanism which utilizes the jamming transition effect of granular material enclosed in an air tight bag. The stiffness-variable property of the mechanism according to the internal air pressure of the bag is investigated, and a stiffness control test had been carried out to determine the speed and smoothness of the change in stiffness of the mechanism. A bipedal walking robot had been developed for use during actual walking experiments using the proposed foot sole mechanism. Planar walking experiments will be carried out to evaluate the performance of the proposed foot-sole mechanism.

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In this paper we propose a new high-speed running method using a two-legged robot. It has high-speed and powerful actuators which enable it to jump. And its asymmetric friction on its feet enables it to move forward. We analyze the motion numerically and prove that the both of its legs leave the ground at the same time in spite of its asymmetric friction. Considering the simulation, we produce a real two-legged robot.

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We present a framework for handling disturbances in a humanoid robot during walking motion. Based on the simplified dynamics of a mass concentrated model, we adopt a two level control strategy based on the actual CoM state space. The switching criteria is determined by the extreme values of the computed ZMP. If the extreme values are within the safety limit, the disturbance can be locally compensated by modifying the trajectory to the goal state. In the other case, the final state is modified. The proposed adaptive control is based on our previously presented walking motion generation scheme based on minimal energy control.

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The purpose of this study is to put the humanoid robot into practical use. The concrete aims are realizing the motion which the humanoid robot don't fall and increasing the moving speed of the robot. In this study, we focus on roller-skates because of its simple mechanism. And we propose skating motion as a new moving method of the humanoid robot. The skating motion is faster and easier to control than walking. The skating humanoid robot has the advantage that it can choose the means of transportation. We examined "Stable skating motion" by both trial and error and simulation. In trial and error, we realized "one leg skating motion" and "swizzle skating motion". In simulation, we made "simulation model" with MATLAB.

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We are developing autonomous mobile robot that assumes application of guide dog and service dog. We designed robot having 4 legs and 8 wheels. The robot can move by wheels on the level ground and move by legs on the rough terrain. Whenever we make the robot go up and down stairs, we were making gait manually before. So, the robot couldn't go up and down unknown-stairs. In this paper, it reports gait generation for quadrupedal wheeled robot to go up and down stairs.

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The child who had a handicap in the motor function is difficult to perform autonomous mobile. Motor dysfunction disturbs movement. Furthermore, it becomes an obstacle even if it puts on mental development. Our research group is manufacturing the electric wheelchair in order that a child with motor dysfunction can move independently. The operational support for the collision avoidance is required in order that a child operates it safely. This research aims at establishment of the collision avoidance which uses an ultrasonic sensor. Wide range environment information acquisition was performed by using some ultrasonic sensors. The situation of the obstacle has realized stop and avoidance by using an ultrasonic sensor.

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The mobile experience of infant stage is important, in order to encourage the development of the cognitive faculty. We are developing an omnidirectional vehicle, which has various functions for handicapped children. In this study, we newly introduce the Kinect sensor as the environment recognition sensor and the operation assist system which yields the collision prevention order using the artificial potential field.

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In this paper, a walker that enables disabled or elderly people to rehabilitate outdoors is proposed. This walker has a pair of rotary cross arms with passive wheels, which allow the body to get over steps. Each arm begins to rotate automatically if the angle of the arm is over the threshold. The user can travel safely because this walker are passive and cannot move unintentionally with driving force. The walker has a small turning circle because the rotary cross arms with wheels are located in front of the body; therefore it has good maneuverability. This paper presents the conceptual design of the walker and the control of the rotary cross arm with passive wheels when getting over a step. The maneuverability of the walker is also discussed. The experimental results of the prototype confirm the design effectiveness.

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Robotic aided therapy has been developed recently in order to improve the an gait rehabilitation on the elderly with a limited gait ability. This paper proposes a rhythm waking assist system using pneumatic actuators, designed to enable an elderly with decreased walking to walk rapidly and participate in daily-life activities without special equipment. The walking velocity of the elderly is improved not by the wide stride but by the rapid pace. This system comprises three modules: a walking rhythm generator, a powered lower extremity orthosis, and a floor reaction force detector. The walking rhythm generator indicates the adequate walking rhythm to the user. The floor reaction force detector judges the state of each leg: swinging or supporting, and the powered lower extremity orthosis lifts the swinging leg. The powered lower extremity orthosis is driven by mckibben actuator. Experimental results confirm the possibility of this system.

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Muscle weakness of lower limbs due to aging interferes with independence activity. The purpose of this paper is maintenance and improvement of function of mind and body to those who care mild. Therefore, we develop a walking assistant orthosis. This orthosis need compact, lightweight and wearable. So, we use actuators which are lightweight, high-output pneumatic artificial rubber muscle. In this paper, in order to downsize equipments installed orthosis, we focused on the air consumption of the artificial muscle and amount of air supplied to the artificial muscle. First, we experimentally confirmed that artificial muscles can reduce the air consumption by thinner and residual pressure. Second, we experimentally confirmed that dry ice as a compressor was effective.

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Currently, the use of communication robots has been attracting attention within the declining birthrate and aging population. For example, efforts have made to improve cognitive function of the elderly. We tried to maintain motor function of the elderly using a small humanoid robot at Long-Term Care Health Facility for the elderly. Through this activity, we surveyed an opinion for the robot and the activity. Therefore, we report the result of it. In addition, we tried to monitor and evaluate movements of the elderly while they do physical exercises, using 3-D depth sensor. In particular, we calculated angle, angular velocity and angular acceleration of elbow and shoulder joint from coordinates of the joint.

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This paper deals with locomotion selection that is appropriate for situation of a robot. Falling Risk is derived from errors and environment information by using Bayesian Network. The robot evaluates the Falling Risk as an indicator of uncertainty. Locomotion selection during walking is modeled as Semi-Markov Decision Process and most appropriate action is selected by using the greedy algorithm. As a result, the robot moves in the environment that is difficult to travel in one action, maintaining the maximum moving efficiency.

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Previously, we have realized an efficient 3-D biped walking based on the Passive Dynamic Autonomous Control (PDAC) that is one of the point-contact methods. However, the stable range of the point-contact method is small and the robustness of the walking is not large enough for practical use. In order to increase robustness of the point-contact method, this paper proposes a swing leg retraction and a double support phase for the point-contact method. The swing leg retraction enhances the convergence range of the walking system; also, by use of the double support phase, the robot dynamics converges to a stable orbit even if a disturbance happens at a foot-contact. The proposed biped walking algorithm is verified by experiments.

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Autonomous underwater vehicles have been used for investigation in underwater or on a seafloor. For this purpose, a legged walking mechanism is one of the good solutions for the investigation since it is able to maintain stable condition on a seafloor. However, a walking robot has a risk of turning over by ocean current and various terrains. This study proposes a new legged mechanism that keeps stable posture even after turning over. This study also proposes a gait for this legged mechanism. To investigate performances, a prototype machine has been developed. It is shown that the mechanism is able to achieve forward movement under turning over.

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I would like to propose a gait of reverse-type tripedal walking robot with link mechanism. Most studies have focused on bipedal or quadruped walking. The purpose of this study is an examination of a new gait. To examine tripedal walking, I constructed the robot model with a simulation soft called "Open Dynamics Engine (ODE)" and simulate its gait. Thus, I get the gait of reverse-type tripedal walking robot with link mechanism.

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This paper presents a fundamental framework for motion generation, in order to explore quadruped dynamic locomotion. In this framework, we utilized an Inverse Kinematics solution which analytically process torso orientation, foot trajectories and center of mass trajectory. Center of mass trajectory is derived using ZMP criterion while foot trajectories are generated through polynomials. What is more, PID control with disturbance observer is used as the servo control. In order to validate the framework, trotting motion is simulated via OpenHRP3. As the result, dynamically equilibrated trotting cycles with sufficient joint tracking performance are obtained. In addition, torso orientation error was measured to be within 1.5 degrees.

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Pressure ulcers are cellular necrosis due to congestion that is the stanching of the blood current in the blood capillary, shear force or moisture. This is because that the contact pressure applies to the same part of the body for a long time. Thus, in this study, we propose a new type of mat system not to occur pressure ulcers for handicapped people who use a wheelchair. This system uses a pneumatic mat. That is to say, the mat element has cloth actuator. Therefore, the stiffness of each actuator can be controlled by inner pressure, so the contact pressure contribution can be changed by pumps and valves. In this paper, we measured about key factors influencing pressure ulcers. In other words, we make a comparison of the pressure distribution and share force by using a mat. As the result, the effectiveness of proposed system is verified through some experimental results.

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In recent years, it is reported that the number of falling accidents of elderly pedestrians tends to increase. As one of this cause, it is considered that the center of gravity position with sole is changed. This is because that the elderly people are difficult to balance the center of gravity position by decline of their leg strength. Therefore, they become easy to fall. Thus, in order to solve these problems, developments of new products to prevent fall motion are desired. In this study, we propose high performance shoes to enable stable walking. That is to say, in order to develop the shoes, we use the Sponge Core Soft Rubber Actuator (SCSRA) as the pneumatic element. The SCSRA can control the stiffness with change of internal pressure of the element. Therefore this actuator can be used as an insole of the shoes. In this paper, the effectiveness of the proposed shoes is cleared through some experimental results.

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Meal movement with exoskeletal robot for elbow which has no forearm rotation DOF poses trick motion of shoulder. However, it is not good for everyday life support robot to add another DOF with an actuator because it makes the robot bigger and heavier. So, in this paper, we revealed the correspondence relationship between elbow flexion and forearm rotation in meal movement, and created an orthotic which has the function interlock elbow flexion and forearm rotation along the lines of meal movement. We measured the trick motion of shoulder with the orthotic we created, and we confirmed that the orthotic we created makes trick motion of shoulder smaller than existing orthotics with no forearm rotation DOF.

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Proper seating is very important for the severe cerebral palsy patients, and has good influence on patients' physical body and mentality. The deformity of the spine causes a gap between a back of a patient and a wheel chair backrest. Generally, urethane cushions are used to fill up the gaps. However, this method cannot completely handle the deformation and posture of users. In this paper, we have developed automatically transformable seating system with air pressure. As a preliminary of the development, we conducted characteristic tests for the rubber bag. Additionally, we developed an intelligent seating system (i-Seating) and we conducted back pressure tests of the i-seating over the wheel chair and desk.

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Locomotion is an important ability in daily life. The intelligently controllable walker (i-Walker) is a computer-aided walking support which recognizes environment and assists walking. The i-Walker uses MR fluid brakes in both wheels to control its walking speed and direction. In this paper, gait measurements of the i-Walker were reported. First, the sensor for gait measurement was installed in the i-Walker. Second, gait experiments were conducted by elderly subjects who have several disabilities.

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The purpose of this study is to develop the supporting system for standing and sitting of the elderly people. The feature of the supporting system is to assist the human motion for standing and sitting without any sensors attached to the people. First of all, we measured a human motion of standing by the force plate and force sensor. As the result, we clarified the feature of a human standing motion. On the basis of the feature, we considered the design guideline of the supporting system. And we made the motion simulator to estimate a human pose during the stand-up motion from the force plate and force sensor data.

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The goal of this study is to develop a bipedal robot with a simplified system. We adopted a Chebyshev link mechanism as a bipedal robot mechanism to reduce a number of actuators. The phase difference of the right and left legs is half a cycle. Therefore, the robot can walk by using only one motor with a rotary encoder for speed control. Then, we built a mechanical foot to mimic a human foot. It is said that a human foot can control body balance and absorb impact forces at the touch down. We installed a spring to the mechanical foot. We used three-dimensional acceleration sensors and inclination sensors to obtain data to evaluate the effect of the mechanical foot. From the experimental data, we observed a positive effect of the mechanical foot.

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The goal of this study is to reveal the relationship between gait and energy consumption of four legged robot. We built a small and lightweight four-legged robot with a simple mechanism to measure the energy consumption in walking and trotting gait. Each leg has one actuator, and motor drivers are mounted on the robot. The current and voltage in the motors were calculated from the signals of the motor drivers and from their rotating velocity, respectively. The power consumption can be calculated from them. In the experiments, we used three kinds of foot trajectories. The foot trajectory can be changed by changing the link length of the drive mechanism slightly. Also, we changed time for one stride. In this paper, we describe the mechanism of the robot and experimental result on the relationship between power consumption, gaits, and its speed.

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Multi-legged robots like ones with six legs have high adaptability to various environments. We make use of this characteristic, and study a 6-legged robot for the purpose of walking in marshy terrain among non-level terrain. In this study, we design and manufacture an 18-DOF 6-legged robot. This robot has one rotary joint and two prismatic joints in each leg. We experimented to measure electric power consumption during the robot's walking in level and marshy terrains. In addition, we compared the influence of marshy terrain on two types of foot shapes. As a result, with this robot, electric power consumption on marshy terrain was slightly higher than that on level terrain. In addition, as for foot shape, electric power consumption with a reverse-dome shape was higher than a dome shape.

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In generally, many robot designers decide a walking algorithm separately from how to sense the around environment. Therefore it is difficult to calculate the gait plan when the estimated environment included some errors. Our study is originated from an idea that we have to integrate the model design and the sensing strategy into a walking robot model. When the robot is walking on the ground, the robot is affected from environment. If environment is different, the robot is affected differently. If the robot is affected differently, the gait of the robot shifts. This paper describes the concept that a walking robot is able to sense a shift of the ground through its walking conditions. Some simulation results show the effectiveness.

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In this research, we are currently developing a 6-Dof oral Interface in order to help quadriplegic patients operate a wheelchair mounted robotic arm independently. We are focusing on building a device capable of measuring the amount of jaw's movement and respiratory pressure and changing it into electronic signals by using joysticks and air-pressure sensors. We come up with a control method which is adapted to the robot arm's 6-Dof tool coordinate system and can be used to operate the wheelchair mounted robotic arm without using hands or legs. The device can be installed instantly by connecting it to the computers with a single USB cable. The device is in a small size of 220×200×90[mm] and weighs 680[g] for compact purpose.

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Beautiful writing is impossible when paresis occurs due to diseases such as stroke. Writing is an indispensable motion on Activities of Daily Living (ADL). We aim to develop write-assist system using finger exoskeletal robot. This paper presents an investigation about finger support method for the write-assist system. Specifically, we analyzed the characteristics of gripping force using a pen on the writing task. It was found that the difference of thumb and index finger force tended to be small on beautiful writers. We will apply this result to the control method of assist robot.

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