We have been developing a semi-autonomous underwater vehicle (semi-AUV) equipped with 3-link dual-arm for underwater intervention tasks. In this work, brief description of the developed semi-AUV and a single-person operated master controller that can simultaneously operate the semi-AUV and dual-arm is described. Furthermore, preliminary experimental results showing the effectiveness of the master controller in controlling the semi-AUV is presented.

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In the management of fisheries resources, observation of a growth process of fisheries resources and presence of diseases or harmful insects is very important. In the farming of wakame seaweed, fisheries resources observation is conducted by raising up them on the surface of the water. However, these operations are conducted by the hands of fishermen and hard labor and physical burden were required. Therefore, we have been developing an underwater robot to assist the observation of fisheries resources. The robot was developed as small and light Remotely Operated Vehicle (ROV). In this paper, the specification of the robot and the system of the depth and attitude control was presented.

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We have proposed a miniature aquatic robot propelled by resonance of elastic plate. In this paper, a new robot that realizes straight and turning movements is developed. The robot including a vibrating motor in the body shell swims forward with a tail fin and turns with side fins. Finally, the steering of robot is demonstrated.

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In recent years, coral reefs decrease in Okinawa. One of the reasons is outbreak crown of thorns starfish. Hence, we have been researching to use underwater robot for exterminate crown of thorns starfish. The authors propose the maritime mobile to measure position of the underwater robot. If you measure object in underwater, usually you can use a sound wave. In this research, develop the maritime mobile which mounts monocular camera and GPS and attitude sensor. And use the maritime mobile to measure underwater objects. The author illustrates miniaturization of maritime mobile based on results experiment on the sea.

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Currently, buoyancy control devices that are installed in submarines and ships mainly use such ballasts as iron balls and water. However, using ballasts harmfully affects the environment and ecosystem. Thus we are developing a buoyancy control device that needs no material exchange with the outside. Recently, we are focusing in the so-called co-generation system to use waste heat for melting paraffin wax. In this paper, we will report a mechanism with the two-step piston that increase buoyancy change, which include a heat exchange mechanism with hot water. From the experiments, we confirmed that the system works, although some problems exist.

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In the current study, we have been developing a wireless sensor network system to support the coral ecological system survey activities for conserving the coral reef environment. In this system, coral images are gathered by stationary underwater monitoring sensor nodes with fixed-point observation. In a long time observation, however, a camera view is interfered because the algae attach to the sensor node surface and grow. Therefore, removing attached algae is important to maintain view ability of camera images. This paper studies attached algae removal function for the sensor node. We investigated attached algae growth in surface of acrylic board which is the exterior material of sensor node, and confirmed that algae growth interfere with the camera view. A prototype of wiper device was developed to wipe and remove attached algae on the surface of sensor node. A wiping action of the wiper device was confirmed in practical environment.

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In the current study, we developed a wireless sensor network system to support the coral ecological system survey activities for conserving the coral reef environment. This paper studies the required functions of a data browsing system to confirm information of underwater environmental conditions gathered by sensor network. Sensor information acquired by each sensor node is transmitted to and gathered in the base station. The base station serves as the Web server. The users such as coral researchers can access monitoring information by using a Web browser. The web page displays monitored information that was gathered by sensor nodes. The Web page can display the temperature and image information of a period required by the user. Each sensor node condition can be checked by selecting the sensor node.

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The AUV may be missing for the trouble that is not expected underwater. Generally, the AUV is expensive and must avoid being missing. Therefore, the experiment in the pool before using it in the real sea is very important. In this paper, We express development and improvement of the AUV for the purpose of the experiment in the pool.

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In this research, a solar-powered environment monitoring system for lake water has been developed. The system employs several drifting buoys to observe lake water quality and flow. A commercial Android device, used as the system controller, is mounted on the buoys and integrates a microcomputer processing data received from several sensors. Sensor data and GPS data are submitted to a server via the Internet. Based on GPS position information, lake water quality information of whole surface from discrete data using method of Lagrange multiplier. By transitions of GPS position information, flow direction and velocity are estimated. In previous works, flow of a lake was estimated by the integrated system. However, a buoy floated on the lake, only surface current flow was estimated. In this paper, to measure and estimate deeper layer current flow, a novel mechanism of a buoy for the environment monitoring system for lake water is proposed.

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An X4-AUV composed of four Ministers is designed and manufactured to develop a small-sized AUV which does not use any rudders. This AUV has four thrusters, but each thruster is arranged at equal intervals at the side of the body, and three attitude motions and the translational motion in forward are realizable by changing the revolutional speeds of four thrusters. First, the construction of an X4-AUV and its motion are explained, together with considering of the added mass. Next, regarding the production of the X4-AUV, several aspects are described in, e.g., the selection of parts, the structure and thrust of a thruster, the manufacture of a waterproofed container, etc. Finally, some experiments are conducted to verify the forward motion of X4-AUV and the rotational motion in each attitude.

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Several AUV (autonomous underwater vehicle) and ROV (Remotely operated vehicle) have been developed. Since those underwater vehicles are expensive, a new underwater observation system which is not expensive is proposed. This system is sunk easy and transmits observation date using the Wi-Fi communication from the sea. In this study, the proposed underwater observation system is explained and characteristics of Wi-Fi communication at sea are verified.

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In this research, we propose a buoyancy control device utilizing volume change induced by pneumatic actuator for underwater robot survey. This device is developed for two purposes. The first purpose of this device is to suppress wasteful power consumption from underwater robot. The Seconds purpose of this device is to prevent underwater robots from agitating the sand. The buoyancy control device is actuated by balloon, Direct operated solenoid valve and compressed air. We experimented with buoyancy control device. Experiments indicate that proposed device could be used for motive power of underwater robots. But, we found a point for improvement in that. We are going to experiment it after improvement again.

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Many aqua robots are in practical use to investigate various aquatic animals. Caudal-fin-driven robotic fish that imitate live fish do not alarm other underwater creatures. Moreover, because such robotic fish do not use a screw propeller, they are unlikely to be entangled with water plants. In this study, two-joint robotic fish have been constructed with servo motor to speed up. To compare for the results of PIV experiments and CFD analysis then evaluate the differences of the propulsion performance by changing the phase difference. It can be confirmed that the angle of the tail fin tip and is related to the angle spread of the vortex. This robot was able to swim like live fish.

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This paper proposes a motion control method for robotic arms mounted on an underwater robot. The method utilizes visual information to realize the position control of the end-effector of the robotic arm. The usefulness of the proposed method is practically verified by experiments.

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This paper describes a new underwater robot for dam inspection. Dam inspection needs exact crack positions. However it is very difficult for usual underwater robots to detect the exact crack points in water due to inaccuracy of position measurement of an underwater robot near a dam wall. In this paper, we propose a new method to detect the robot position by using pivoting motion of the robot. For pivoting motion, a moveable buoyancy mechanism and two contact rods are effectively utilized. The robot position is calculated by the previous rod position of the attitude angle geometrically. The performance of the proposed robot system is demonstrated by experimental results of Miyagase dam located in Kanagawa Prefecture.

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In this study, we introduce long-pulse Laser-Induced Breakdown Spectroscopy (LIBS) as an in-situ analytical method to investigate the chemical composition of solids submerged on the seafloor. We have developed a real-time in-situ LIBS sensor, "ChemiCam F", for deep-sea chemical surveys. In sea trials in 2013 and 2014, in-situ measurements of natural rock composition were successfully performed at the depth over 1000 m, and it is the first time that in-situ multi-elemental analysis of solids has been achieved in the deep sea. The results suggest that LIBS can form the basis of a practical tool for deep-sea chemical surveys.

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Telexistence system can provide artificial experiences that we cannot experience in everyday life. In our previous work, we proposed an underwater telexistence system that provides swimming experience with dolphins by using a towing underwater robot. In this paper, details of a developed robot are described. The robot has a 2-DOF gimbal for a camera and 2 sets of rudders. Head motion of an operator synchronizes with that of the camera gimbal to provide feeling of presence. The rudder can be telecontrolled by the operator. A 9 axis motion tracking sensor is installed to achieve motion stabilization.

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Authors have been developing the underwater robot which can be used for environmental protection work in the sea near Okinawa. GPS is used for position measurement. But GPS is not work in the water and it is difficult to obtain the position of the underwater robot. Our research field (Okinawa sea) is high transparency. So we are developing position measurement system of the underwater robot using the monocular camera. In this paper, it describe the position measurement system. Also shows the results of position measurement experiment in coastal sea area of Sesoko Island.

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In this study, the development of an underwater robot for surveying radioactive materials on the lake bed. Several methods have been proposed for soil core sampling using underwater robots but these methods have high risk of the robot being unable to detach from the lakebed. This paper, describes the improvement of undisturbed soil core sampling module of the robot. Revised sampling methods and new modules are evaluated.

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This paper presents robust stabilization of a powered paraglider and its application to aerial shooting experiments. By considering uncertainties for aero-dynamics of a canopy, we construct two kinds of nonlinear models that correspond to the longitudinal and lateral motions. Two robust controllers for the longitudinal and lateral motions with the uncertainties are separately designed using a linear matrix inequality based design. The designed controllers guarantee the stability of the closed loop systems for the longitudinal and lateral motions with the uncertainties. The experimental results demonstrate the utility of the robust controller design and realization of the aerial shooting tasks.

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In this paper, we propose a solution for grasping and moving long-size payload such as pipes or wood using a multirotor helicopter. In order to perform this task, a couple of grippers were mounted under the helicopter for a better grasping and safe transportation. Some experiments performed show that the helicopter can safely grasp and move the payload to another place. By means of an on-board camera, the helicopter can provide visual information to the user at the moment of the aerial manipulation using either a First Personal View video goggles or a small monitor. The complete system is commanded using a single radio control.

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The trial production of new concept vertical take-off and landing aircraft (VTOL) based on tricopter was carried for aerial, observation and research. The VTOL is made up of the fixed angle three motors located reversed T shape, fixed wing with elevon and rudder. The proposed aircraft is made by minimum components compared with that of already published VTOL base on quadcopter. Continuous transition from the rotorcraft to fixed-wing aircraft can be done completely with 90 degrees tilt of the aircraft.

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This report shows a newly developed large ground control unit for a large scale kite-based tethered flying robot in order to increase the payload of flight unit. We have proposed the kite-based tethered flying robot with long-term activity capability. This research aims at realizing a wind power generation system and a flying observation system which complements other information gathering systems using a balloon or an air vehicle. The newly developed ground control unit has a capability to drag the tether line of the kite 100 [kgf] at 0.5 [m/s] and 15 [kgf] at 5 [m/s]. This report also shows how the ground control unit works with the kite and flight unit in the real situations.

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A newer rotor craft which can attach and move on the ceiling was developed in this paper. Four propeller are used not only flying but also attaching on the ceiling with vacuum suction. Experiments to check the special functions were carried out with the developed testbed system.

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For an unmanned autonomous vehicle, it is important to estimate its position and attitude precisely. Pressure altitude is effective to improve the accuracy in state estimation. It is known that the pressure altitude is affected by ground effect. In case of helicopters with a single rotor, the ground effect is supposed to appear when the altitude is lower than the diameter of the rotor. The helicopters equipped with multi rotors in the same horizontal plane, it is supposed that ground effect would appear higher altitude than the diameter of the rotors. Using quadrotor helicopters, experimental data is collected, which explicit the impact of the ground effect.

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New rotor wing type UAV is the aerial vehicle which has a stator wing mechanism to deny the anti-torque by the main rotor. The stator wing is the wing attached under the main rotor. The stator wing causes torque to the body by the downwash of the main rotor and performs attitude control by the torque. This rotor wing type UAV was named SWUM. It perform a horizontal mobility by doing attitude control of an aerial vehicle by control of stator wing angle, not pitch angle control of main rotor bride. The validity of the attitude control by stator wings was confirmed by numerical simulation.

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This paper proposes a new all-round Air-Land-Sea Unmanned Aerial Vehicle (UAV) and the automatic battery exchanging device. The new UAV is a quadrotor helicopter with two rolling protect-flames, and can not only fly in the air but also move on the ground, the wall, the ceiling and the water. Firstly, some new UAVs are presented to move on a wall in a horizontal direction. Secondly, a new automatic battery exchanging device for the UAV is developed based on ground running motion without precise landing from the air. The proposed method can complete the battery exchanging safely even in windy outdoor.

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There are approximately 700,000 bridges which are bridges of 2m over a bridge length in Japan. At intervals of once every five years, it is necessary to inspect the bridge. That is, it is necessary to inspect the bridge 140,000 per year. In addition, reduction of experts bridge a decrease in tax revenues due to declining birthrate and aging population is a problem. Therefore in this research reports on flight experiments to build a control algorithm to fly by avoiding contact with the structure semi-autonomously implement the sensor to multi-copter for the purpose of detection of cracks in the space under the bridge

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This study aims to apply Sliding Mode Control (SMC) to autonomous flight systems in real conditions. Although SMC can show high robustness to disturbances or modeling errors, for small flight vehicles the time delay in a control loop may be critical, because flight systems become easily unstable in air. In this study, a Quad-rotor vehicle is used as an example of flight systems. The effect of time delay is examined in computer simulations using the specifications of a real Quad-rotor vehicle. As well as a time delay, the effects of disturbances and modeling errors of the vehicle are also studied. Finally, we discuss the feasibility of applying SMC to a Unmanned Air Vehicle.

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The mobility and the large area are evaluated, and tilt rotor type vertical takeoff and landing (VTOL) machine is being expected by not only the army but also the private organization. A lot of same shape types are demanded unmanned aerial vehicle (UAV) in addition. However, because the tilt structure and the head structure of the rotor are complex, Osprey is unsuitable to cheap UAV. It aims to simplify the structure when tilt rotor type VTOL machine is made UAV and to research and develop the method that is appropriate for UAV in the present study. It pays attention to three rotor type with easy structure in this report, and do the study of making of tilt rotor type VTOL UAV.

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This Paper proposes a system of multi-rotor helicopter which is hanged by cable. In the system, a cable winder controls the cable length. Under the cable length control, the helicopter can fly keeping a constant height without cable sag. We suggest a control method of the system including feedforward control. Experiments illustrate that the feedforward control improves the helicopter response in swing direction.

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Chemical Plume Tracing (CPT), locating the distant odor source in a turbulent environment, has been studied for robotics odor source search. Many robots moving on the ground are designed. In real-world, however, obstacles on the ground prevent the robots from approaching odor source. Flying CPT robots can approach odor source even if obstacles are on the ground, so design of the the flying robots are needed. We propose flying CPT robot system which can inhale odor ahead of the robot and detect the odor. This system is installed CPT algorithm of 2-dimension and the flying robot can locate the distant odor source under constant altitude condition.

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In recent years, a wide variety of robots that can be used in the human living environment has been studied. Then, in such environment, the robots need to find where they are if they support human. Therefore the purpose of this study is to suggest a human tracking method of a multi-rotor craft with the HOG algorithm using the image of a monocular camera installed on the multi-rotor craft. This study showed that multi-rotor craft can performed human tracking by the method proposed in this study.

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Quad tilt rotor Unmanned Aerial Vehicle (UAV) solves the problem of underactuated system in general quadrotor UAV. The quad tilt rotor UAV can control position and attitude independently by tilting directions of propellers. However, the flight control system in a wide range of attitudes has not been discussed yet, for example UAV flying and hovering with a 90 [°] pitch angle and can flip over when the range of the tilting motor rotates wide enough. In this paper, we present the flight control system for flight condition with a ±90 [°] pitch angle significantly differs from that in a conventional quadrotor UAV flight. We verify the adequate control system for flight in a wide range of attitude conditions through flight experiment.

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We have been developing the MAV with a passive rotating spherical shell for bridge inspection. However, there are issues such that the spherical shell occludes the environment in the on-board camera image, and can be hit by the hammering machine. Therefore, this paper proposes a method to estimate the rotation state of the passive rotating spherical shell with a on-board camera image. To realize it, we evaluated spherical shell recognition performance of feature point detectors, and made the rotation model of spherical shell.

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This paper describe the air-ground use flying robot. This flying robot consists of spherical outer frames, coaxial rotors, rudders and a body system. Its weight is 1311 [g], its diameter is 400[mm], and its maximum thrust is 1950[gf]. The outer frame structure can reduce collision force when the robot lands and be used to drive on the ground. The flying robot has ultrasonic distance sensor and inertial measurement unit sensor (IMU) to measure its height and attitude. Its yaw angle is controlled by using two rotors, and pitch and roll angle are controlled by using rudders. Through a hovering experiment, the effectiveness of the mechanism was verified.

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In this paper, we proposed an adhesion mechanism using an electro permanent magnet for unmanned aerial vehicles (UAVs). We aim to realize remote fixed-point observation by UAV with the proposed mechanism, by adhering to a metal object in the environment, instead of rotating propellers that consumes large amounts of power. We introduced the principle of the proposed mechanism that theoretically make the adhesion robust against swing of the vehicle body, and enable a continuous control and an estimate of the adhesion force. Also, we performed quantitative evaluations of the actual mechanism and reported the results that demonstrated those expected advantages.

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Helicopter system in which the helicopters are connected with multistage cables to the ground station is developed. The helicopters have virtually unlimited flying time by virtue of power supply from the ground station through the cable. In addition, the multistage helicopters have larger flying range avoiding touching their cables to obstacles. Chain like cable and cable feed devices with sprocket are developed to control cable length and cable tension. Flying experiments are performed to validate the developed system.

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This paper suggests cable tension compensation control for helicopters cabled to the ground station. This method can be applied to human operated system and reduces required skill. In this method, cable tension vector is measured by a force sensor and an angle sensor mounted on the helicopter. Thrust and helicopter attitude to balance with resultant force of the tension and the gravity force are calculated and added to control input by PID control.

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Recently, flying robots such as multicopters are being used for various indoor and outdoor situations. The methods for operating a multicopter are either programming a flight path or using a controller. However, both methods require user preparation in order to control a multicopter as expected. This research proposes a finger-pointing multicopter operation method that uses a Kinect system and position error measurement. As a result, it has been found that it is possible to reduce the error by calculating both finger-pointing and head position coordinates with the aimed targetposition determined by body orientation. Further work will include a finger-pointing smartphone application and a program for operating a multicopter in a simulator.

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We showed that BF normalization is equivalent to minimum mean square error with the constraint, and that BF normalization is more accurate scheme than QPM and MPM normalization in the numerical experiments of a UAV.

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Thousands of patients suffer from knee instability as a result of a variety of conditions. Wearable robots have therefore attracted attention as an alternative for restoring lost function and extending the physical function. These robots, however, also often exert resistance force on the wearer due to a lack of consideration of knee rotational movement. In this study, we have therefore focused on knee rotational movement and have found that it is possible to steer the knee joint in the appropriate direction by using two actuators. We measured the amount of misalignment caused by the interaction of the wearer with the device using a motion-capture system. As a result, we have confirmed the validity of a developed robot.

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There are many kind of involuntary action. Especially, the authors focus on the essential tremor. The incidence of essential tremor is high and it has a bad effect for activity of daily life. However, approach to treating essential tremor is symptomatic therapy because the pathogenesis is not clear. We developed an equipment for patients of essential tremor to support activity of daily living. The equipment targets the wrist because essential tremor develops most frequently in the wrist. The equipment has bag structure made by plastic film and it expands by air pressure. So, the equipment is lightweight, compact and wearable by using air pressure.

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We propose a biometric technology that uses skin surface deformations of amputated upper limbs. In this technology, an input device containing a strain sensor is pasted on the forearm and reads skin surface deformations caused by forearm twist motion to gain an input signal.

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These days, population outflows increase from the district to the urban area by the opening to traffic of the expressway. By a population outflow, a traffic inconvenience area occurred in each place of the whole country in the district. In addition, The vehicle that has been being produced for elderly person until now has some problems such as heavyweight, expensive cost, and it is difficult to move when the battery gave out, so only some people is able to purchase it. Besides, although a power-assisted bicycle is light and able to move even out of battery, it can be used on only roads for the size, not sidewalk, so the risk of accidents is increased. Therefore, this paper explains about the research and development of vulnerable road users support city commuter with excellent accessibility as new mobility turning into existing transportation.

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This study focuses on the strength training for the elderly people to sustain the ability of independent walking. The strength has the ability to combat weakness, frailty and their debilitating consequences. Therefore, we developed a new strength training machine offering five kinds of exercises particularly for lower limbs; it has the dynamic load control system as the load can be changed appropriately during the exercises. The experiment of estimating the effects on dynamic variable resistance with dynamic load change has been conducted. In this experiment, the subjects trained using the new strength machine and we measured subjects' muscle fatigue by surface electromyogram and Near-Infrared Spectroscopy. The results of experiment show the effects of changing load dynamically during training sessions: the muscle fatigue slower than using constant load in case of the measurement by surface electromyogram.

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There are a lot of patients with movement impairment who are paralyzed by brain stroke. Sufficient rehabilitative training is necessary for these patients. rehabilitation support systems using force display devices are expected to quantify the effects of rehabilitative training and enhance the motivation of patients and rehabilitation effects. Development of Rehabilitation System for Upper-Limbs with Compactness and High Portability PLEMO-P7 at FURUSHO Laboratory of Fukui University of Technology is presented in this paper.

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Furusho lab have been R&D it low price and safer safety Rehabilitation system PLEMO series. State of PLEMO series one of the inside PLEMO-OLC

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This research reports the initial work of a novel non-invasive method to evaluate a person's workload (fatigue). This is done by using a non-invasive optical sensor that will help to assess the subjective workload. Our system utilizes dye sensitized solar cells (DSSC) as optical sensors, for line-of-sight (LOS) and eye movement detector. Since the workload will be reflected in this eye movement, we assess it under NASA Task-Load-Index (TLX) protocol, a multidimensional scale methodology. 3 out of 5 subjects were found to have good correlation between the workload and LOS.

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In this paper, a control system for electric wheelchairs based on electrooculography (EOG) was developed, so that disabled persons having a disability in muscles such as amyotrophic lateral sclerosis (ALS) patient can control the electric wheelchair by their eye movement. EOG signal is measured by four electrodes which were attached around user's eyes. Then, five kinds of user's eye movements, namely right gaze, left gaze, up gaze, down gaze and blink, are identified by threshold criteria. Thus, using the motorized control device of the joystick developed in our previous study, the electric wheelchair can be controlled by a command assigned to user's each eye movement. To assess the developed control system, accuracy of identification for eye movement was investigated and experiment of slaloming was executed. As a result, 87.5% identification accuracy on average was obtained for five subjects. However, in EOG based control, running time took about three times as compared with the manual joystick control.

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