For an exploration in very large scale field, it is necessary to establish very-large-scale(VLS) multi-robots system and a localization of each robots. Then, we have proposed a novel localization algorithm of VLS multirobots system. The proposed algorithm is based on an ad-hoc network between each robots and "Mi-Nashi trajectory". In this paper, to investigate the validity of proposed algorithm and the feasibility of the exploration by VLS multi-robots, we conducted numerical simulation of the exploration of one or multiple objects by VLS multi-robots system.

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Legged animals exhibit adaptive locomotion by coordinating leg movements. Biological findings suggest that such locomotion is controlled in part by an intraspinal neural network called the Central Pattern Generator (CPG), which is capable of self-organizing movement patterns between legs. In our previous study, we have proposed an unconventional CPG model that fully exploits physical interaction between legs. Experiments with quadruped robots showed that the CPG model enables the robot to reproduce various gaits without any interlimb neural connections. The purpose of this study is to verify whether or not the same CPG model would also be valid for a hexapod. To this end, we constructed a hexapod robot and conducted verification. Experimental results show that our robot can successfully self-organize stable walking pattern called metachronal wave gait in hexapod locomotion.

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Quadrupeds have versatile gait patterns, depending on the locomotion speed, environmental conditions and animal species. These locomotor patterns are generated via the inter and intralimb coordination and are partly controlled by an intraspinal neural network called the central pattern generator (CPG). In our previous study, we have proposed an unconventional CPG model that fully exploits physical interaction between legs. Experiments with simple quadruped robots showed that the CPG model enables robot to reproduce various gaits without any interlimb neural connections. The purpose of this study is to extend our CPG model to more versatile and adaptive locomotion generation on an artificial muscle-driven quadruped robot.

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In this study, we developed multiple mobile robots to perform group escape behavior by mimicking fish school. And we developed simulation system and an experiment system for robots evaluation. Fish school has two characteristics -"Schooling" and "Group Escaping Behavior". "Schooling" is a cooperative behavior, moving slowly in the same direction and the same speed. "Group Escaping Behavior" is a cooperative behavior of higher propagation of its sate and move quickly, when agent has found enemy. Our system's interaction has not only 1 input but also many inputs. Robot behavior is quickly by increasing the input. We verified the effect of increasing the input number.

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The 1-inch gas pipes are used in houses and between gas meters and the main pipe which lies under the road, and requires regular inspection. However, an endoscope has the limit of the scope on inspection. In addition, in-pipe robots cannot pass through a 90-degree elbow, whose radius of curvature equals its inside diameter. In this study, we developed the peristaltic crawling robot with pneumatic artificial muscles for 1-inch gas pipes. This robot can pass through the elbow horizontally and vertically. In addition, this robot can be equipped an endoscope. However, this robot cannot pass through the continuous elbows. It lies in the actual environment certainly. In this paper, to use a robot in the actual environment, we developed the robot which can pass through the continuous elbows. We experimentally confirmed that the robot can pass through the continuous elbows.

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In this study, a new method to advance and to carry wired sensors like a camera inside narrow and curving pipelines is proposed, which is aimed at watching the condition inside the pipelines. In order to increase the advancing distance and to carry a wired camera, the alternately-actuated drawing out type drive is proposed. In this method, since the tube is alternately pressurized, the area of the tube which passes in Λ-drive can be confined. As a result, the robot has many features with the superiority of the drawing-out type drive actuator. Finally, it is experimentally verified through experiments that this robot is able to go through some narrow and curving pipelines.

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Flexible mobile robot aims at moving by carrying out modification elasticity of the outer shell. If realizable, various work can be performed for ambient environment and the purpose. The problem of the previous researches are large output loss, small load capacity, external power supply and etc. These problems are caused by difficult keeping to the shape of these shells. This paper is new concept robot "Paramecium" which is flexible mobile robot, and mechanical design of it. It is flexible mobile robot with granular material without an expansion element

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The trident snake robot is an example of wheeled mobile robot whose dynamics is described as a nonholonomic kinematic equation with three control inputs and six state variables. In contrast to the authors' previous works on locomotion control for this robot with centralized control, this paper challenges to achieve locomotion with decentralized control, that each system has own controller, by using oscillators. We examined motion generation of the proposed idea by passive spring joint and neural oscillator networks.

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In this paper, we introduce new hybrid mechanism which composed of "Traction Arm" and crawlers for forestry robot. Traction Arm is new method to improve climbing ability of crawler robot. With 3-DOF robot arm, generate piercing and pulling motion of ground contact point. We are developing the robot system, which combine "Traction Arm" and crawlers. We made the prototype machine and confirmed effectiveness of the new mechanism through field tests.

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This paper is concerned with a new model of nonholonomic system, the tetrahedral aerial mobile robot with vertex-mounted fins. This robot is in the class of four input kinematic nonholonomic system, called first order system, where the first derived Lie algebra of control vector fields spans the tangent space at any point. In this paper, we propose a new robot model of nonholonomic aerial mobile robot. Then, we investigate the movement of the robot (e.g. translation and rotation) and propose a fundamental control algorithm, named two-step control, with the combination of a periodic input and a constant one.

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A variety of mobile robots have been developed for operating in difficult environments. Most of them are mounted with wheels or crawlers for locomotion. However, wheels and crawlers cannot be sealed against water or dust easily. Thus, we focus on developing a new propulsion mechanism and proposed "Rotary Surface Wave (RS-Wave) Mechanism." RS-Wave mechanism generates propulsive force from the whole body and features a simple structure with water and dust tight properties. In this paper, the modification of RS-Wave mechanism and its application on mobile platform is introduced. The design of this mobile platform is explained, and basic experimental results are presented.

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The traveling wave type omni-directional mobile robot imitates the snail locomotion mechanism. An advantage of this movement mechanism is that it enables stable motion because of a large contact area. We think that this stable motion is applicable to wall climbing. In this paper, we developed magnetic adhesion mechanism for moving on ferromagnetic surface and also the traveling wave type omni-directional wall climbing robot using developed magnetic adhesion mechanism. Furthermore, we confirmed the performance of this robot through experiments.

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When using a light weight and low powered arm to perform object grasping tasks of an inverted pendulum assistant robot, accurate modeling is difficult. To solve this problem, the system is separated into the manipulator and the body, and separate disturbance compensation is performed for both. This paper presents the simulation results of controlling the position of the end effector when applying disturbance compensation control using the extended state observer are presented.

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Cylindrical Rolling Robot, a cylindrical mobile robot with one eccentric rotor, has complex and interesting dynamics especially when rolling on its edge. In this study, we propose a simple control law to make the robot follow static circular trajectories only by one degree-of-freedom input. Some simulation results indicate that the proposed control law was effective to make circular trajectories and also maybe other given trajectories.

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This paper proposes a method of controlling an Inverted PENdulum Type Assistant Robot (I-PENTAR) when using the attached robot arms. Coupling forces and unknown factors occur during execution of target tasks that use the arms of the I-PENTAR. Therefore precise modeling of the robot and arms is difficult. This paper presents the combination of Active Disturbance Rejection Control for compensation of unknown dynamics and feedforward input. Results regarding the control method and swinging arm tests during stabilization of I-PENTAR are presented.

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In this paper the control of an Inverted PENdulum Type Assistant Robot (I-PENTAR) in motions where the state of the system is far from the equilibrium is examined. Since the inverted pendulum is a nonlineear system, linearization near its equilibrium point must be performed for linear controllers to be used. Although this is sufficient for stabilizing the system close to the equilibrium point, degradation of the performance can be expected as the operating point moves further away from the equilibrium. This is due to the fact that static feedback gains no longer match the plant parameters. A dynamic controller with a wide operating region is desirable because there is no need for a switching control strategy with complicated switching conditions. Such a controller based on the Extended State Observer is applied to the I-PENTAR system to achieve motions that are far from the equilibrium point. In particular, the standing up motion of the I-PENTAR is tested and results are presented.

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In this paper, we propose a new kind of nonholonomic mobile robot called trident strider. It consists of a base-link and three links having a free wheel or knife edge like a fin. And each link is connected to the base-link by a linear joint. We analyze the dynamics of the robot, and investigate a control method for the robot to steer it to an arbitrary position. And we developed a robot which moves on surface of water as a real-life example of the trident strider.

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In irregular ground, mobile is required to have high performance of running and dustproof. However, to make mechanism of endless track dustproof is difficult. Then, we focused on how to move the snake and earthworm. They are high performance of and dustproof, because mechanism doesn't form endless track. In previous studies, the devise space of robot is limited. In some situations, movement of mobile which equip devices more than expected would lack stability. Therefore, to equip several transfer mechanisms with mobile is desirable to distribute the load of devise. In this paper, we report the suggestion called "Pressure Wave Moving Mechanism" which is generation of multiple parallel wave in order to carry the large load, the development and the experiment of prototype called "Surf type.P".

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The pico-EV Eco Challenge 2013 was held at Kanagawa Institute of Technology. Participants compete the 20 minutes running distance using only six small rechargeable Ni-MH (Nickel metal hydride) batteries. Eleven vehicles with approximately 100 persons were participated. The champion was able to run approximately 3.7km. This paper will present the administration and results of the completion.

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A series hybrid electrical vehicle with a bio fuel diesel engine generator, named as Bio EV, is proposed in this paper. The diesel engine rotates an electric generator using straight bio fuels such as sun flower oil. The hybrid electric vehicle is able to run using the generated electricity. The electric generator is also able to charge the electricity to batteries. It is expected to realize a long distance running electrical vehicle, and also a carbon neutral system. This paper will explain the concept of the Bio EV, the design of the electrical vehicle system, the running experimental results, the bio fuel diesel engine system, and the cultivation of sun flower and rape blossoms.

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For the elderly people, it is developed the caring type ultra-lightweight electric tricycle: pico-EV using the bamboo with engineering examination. The EV is easy for shopping and movement, and it runs in low velocity. In order to raise the rigidity and strength of parts, the angle ply laminated plates which carried out for a thin bamboo fiber sheet to arbitrary angles was developed uniquely. Since the newest EV is a decomposition type, it can be carried as baggage in the airplane of an international airline and a domestic one. In this paper, the pico-EV which developed by students in about ten months, it makes a reference with the past circumstances.

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A series hybrid electrical vehicle with a bio fuel diesel engine generator, named as Bio EV, is proposed in this paper. The diesel engine rotates an electric generator using straight bio fuels such as sun flower oil. The hybrid electric vehicle is able to run using the generated electricity. The electric generator is also able to charge the electricity to batteries. It is expected to realize a long distance running electrical vehicle, and also a carbon neutral system. This paper will explain the concept of the Bio EV, the design of the control system.

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We propose a combined-type continuously variable transmission which has quadric-crank chains, one-way clutches, spur gears, and a plate cam etc., as one of the conduction mechanisms. Since the proposed mechanical design is not based on friction conduction, it provides advantage for creating no noise and no slip, and maintaining high transmission efficiency. In this paper, we explain about motion analysis in lever crank mechanism, and design of grooved cam using an envelope curve, as one of the plate cam. It has an advantage point that the synchronization between the rotation of cam and the one of crank at the input axis can be taken mechanically without any electrical control.

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PICO-EV competition is to compete the design technique using the vehicle developed by the students. I have instructed the group of students and developed two vehicles. In this paper I will focus on the manufacturing training through the development of PICO-EV and report the process of the development.

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It is important to connect knowledge and feeling which based on own experience at education of engineering. Thereby I think that the capability to observe is nourished. Such experience is important in the design which does not perform craftsmanship However, experience is insufficient for a young man in recent years by educational change. Then, college students have experienced work by making Automobile. And education which has the sensitivity supported was performed.

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We have designed a vehicle using only six rechargeable Ni-MH(Nickel metal hydride)AA batteries as source of power for pico-EV Eco Challenge. In this design, "cheapness, handiness, and simplicity" is thought as important. Specifically, a gear box was used as a power transmission device, a bicycle as a main part frame and maxon DC motor 273752 as an actuator. And, revolving speed of motor was controlled by PWD control using MOS-FET. Next, the running test was done in order to evaluate the quality of the vehicle. As a result, in the regular run, the average velocity was 2.7 km/h and the average power was 9.3W. And, we participated in the eco-challenge convention with the vehicle.

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Recently, an electric car is the focus of attention, with concerns about the environment. However, These electric cars have problems with cruising range, infrastructure building and so on. Especially, in country side, it is very difficult to develop the infrastructure for electric cars. Then, our design concept decide to make energy in simple batteries which is sold in supermarket and so on. And, our car designed only a few small batteries (unit 3 type: 6 batteries). However, if this small car are used by general, it need high level efficient for energy. In this research, we aim to reduce the resistance for eco-car. Therefore, at first, we designed the electric car body to reduce air resistance. In this paper, we modeling eco-car body simulant migrant for efficiency improvement of Eco run car. We report the result of wind tunnel experiment.

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In order to spread electric vehicles, those low-pricing and high efficiency are indispensable. DC motors are budget prices compared with AC motor, and their control device are also simple. However, the efficiency of DC motors is inferior to which of AC motors. In this study, a DC motor and a CVT are combined. CVT (Continuously Variable Transmission) has the feature that arbitrary gear ratios can be produced continuously. The purpose of this study is to control the gear ratio of CVT to drive the motor in the state with efficient at all times according to operation of environment and a driver.

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This paper presents that generating mechanism of shaft voltage leading to electric erosion. The voltage generator of shaft voltage is expected to be cause by voltage in winding wire. We construct circuit of interior motor and do predictive simulation of the circuit. We measure the neutral voltage and draw a comparison between predictive value and measured value. As a result, there are obvious connections between predictive value and measured value.

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This paper introduces a novel application of giant magnetostriction materials which is able to generate electric power by utilizing a reverse transduction of the material called Villari effect. The generator is assumed to use ambient vibrations as an energy source which are commonly available in our daily life such as vehicle vibration in driving, traffic-induced ground vibration or bridge vibration. We mainly use Terfenol-D as a magnetostriction material in order to develop two prototype generators, one large and one small. The basic characteristics of the generators are examined such as power generated and effect of prestress. In particular, the experimental results indicate that the compact generator is suitable for energy harvesting. The generator itself is quite rigid and its resonant frequency is in the order of a few kHz. However, according to preliminary experiments conducted, the generator can harvest non-trivial energy out of even low-frequency vibration such as less than 10Hz. Also Terfenol-D and relatively new Galfenol are compared in their performances.

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In this paper, a trajectory planning method of automobiles for collision avoidance by extending the hydrodynamic potential to dynamic environment using local sensor data is proposed. This potential approach for guiding mobile robots has already been proposed in our previous research. It has no maximum or minimum points and can generate the smooth trajectory in real time that is represented by velocity vectors directly for collision avoidance. This previous method cannot consider vehicle dynamics and local sensor information. To cope with the difficulty, a vortex field is calculated by using a velocity of the host vehicle and distance to obstacles. Simulation results for constructing potential fields using both virtual data including a host vehicle's position with lane information and sensor data measured by a laser range finder on a small vehicle show that the proposed method can generate smooth avoidance trajectories that can be traced by automobiles with vehicle dynamics.

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This paper presents a biomechanical and psychophysical simulation system for analyzing and/or predicting operating loads in dynamic driving, such as joint-motor burden, seat pressure, and perceived reactions, on the basis of human sensory-motor properties and vehicle characteristics measured. Simulation experiments in a case of driving the curve road are conducted according to seat heights, and demonstrate that the proposed system can evaluate the operating loads according to driving posture and vehicle behavior. It also shows that the system would be useful for the regulation of vehicle characteristics in order to make human drivers feel the desired operating loads intended by a designer.

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For the purpose of increasing the Global Navigation Satellite System (GNSS) availability and efficient measurement, a path planning for Mobile Mapping System (MMS) is proposed. However, this is not real time planning. Therefore, measurement precision decreases when MMS run in traffic jam. In this paper, we propose recalculation method of a path planning for MMS with Nearest Neighbor method. And, we conducted evaluation test. The evaluation test verified that the proposed method can increase 3.1% of the epoch that gets GNSS fix solution (FIX ratio) and 12.3% of the distance that gets GNSS fix solution (FIX cover ratio) under the same geometry of the GNSS.

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This paper proposes a parking line detection and self-localization method for an automatic parking system by using a camera. Goal decision and self-localization are problems for path planning. Therefore, this paper aims to solve these problems by detecting the parking line by the camera installed on the back of the vehicle. A driver only has to click a broad goal area and a part of the parking line on the camera image in the beginning of parking. Then the parking line is detected and the goal position is decided by image processing. After that, the relative car position is estimated in global coordinate system.

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Recently, fully automated autonomous vehicles have been developed, and field examinations in public road have also been conducted, especially in United States. In this paper, preparation of our laboratory toward field examination of the autonomous vehicle is reported. Additionally, system overview of our autonomous vehicle is introduced.

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Recently, automatic braking systems have been conducted to the research and development. But existing systems cannot be able to avoid collisions in a scenario such as a pedestrian darts out at into driving lane. In such scenario, it is necessary to develop a risk assessment algorithm based on hazard anticipation such as an expert driver. Therefore, this study proposes a risk assessment algorithm based on risk perception of human drivers. First, the vehicle behavior is determined by the application of Potential Fields theory with considering risk perception of human drivers. Next, develop a vehicle dynamics control system based on proposed risk assessment algorithm. Finally, the effectiveness of the proposed system is verified by experiments using the micro-scale electric vehicle.

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Predicting hazards regarding pedestrians dashing to roadways is necessary to reduce the number of pedestrian accidents in unsignalized intersections. The purpose of this research is to develop a hazard-anticipatory driving assistance system to prevent crashes with moving pedestrians in unsignalized intersections. This paper describes hazard-anticipatory driver model using risk potential of collision with pedestrian which can simulate expert driver's driving in unsignalized intersections. This driver model is constructed on the basis of urban roadway driving data by instructors of a driving school. By using of the driver model, the predictive braking assistance system is constructed for collision avoidance with pedestrian. Finally, the evaluation of the predictive braking assistance system is verified in nearmiss incident scenario by using a driving simulator.

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Most of conventional vehicle motion control algorithms have been developed assuming that the relation between the tire-road friction and the slip rate of the tire is linear. Designing a control scheme, assuming that the relation is no more linear, could enhance the safety of the vehicle. In this study, a sliding mode controller is designed for a steady-state circular drift of a vehicle, where the linearity does not hold. Simulation results show that the vehicle motion could be stabilized by the proposed control system.

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As the number of automobiles in the world is increasing, problems associated with environment and safety are becoming serious matter. One of the solutions to these problems is platooning of trucks. Platooning means a number of vehicles form convoy and automatically run in one group. Platooning makes mileage good and enables the number of traffic accidents to decrease because of automatic operation. In existing study of our group, the shift of the vehicle was fixed. This is one of the problems for practical realization. In this paper, parameters of a truck for each shift are identified and a method of the shift change is proposed in order to reduce the spacing error.

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Nagasaki Prefecture has promoted a project for practical penetration and operation of EV(electric vehicle) and ITS(intelligent transport system), "Nagasaki EV&ITS Project", in Goto islands, Nagasaki. Since this project reaches the final year in 2013, a strategy for the succeeding project is on discussion which utilizes the valuable resources of advanced infrastructure, environment, human network and so on. In this paper, an idea for the strategy is proposed to develop practical operation fields to accelerate researches and developments for next-generation mobilities as micro e-mobilities and indispensable technologies for them as autonomous driving and driving assistance.

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For an autonomous vehicle, the extraction of road region is one of the important function to achieve a safety travel. In this paper, we propose a road region extraction technique using a stereovision system. This technique is based on the model fitting with a quadric surface model. However, a quadric surface model fitting has a problem that a result is not stable in an obstacle on road surface vicinity. In order to avoid this problem, we propose a pre-processing that selects necessary point clouds for the road surface fitting. Additionally, to extract a complex road surface, a quadric surface model is fitted to point clouds toward depth direction in partially. These are composed few simple processing, so it is able to extract a road region at fast.

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A rescue robot's and others have to get over various obstacles. However, robot's high ground-covering ability has problems such as its structure becoming complex and losing energy efficiency. In this research, we consider how to get higher ground-covering ability by changing wheel shapes, and investigate a wheel having rimless shape with functionality of foot.

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This paper describes a novel EDLC regenerative braking control scheme of electric powered wheelchairs for efficient driving planning. Electric powered wheelchairs which generate the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the energy efficiency has to be further improved because it is driven only by the battery energy. This study proposes a capacitor regenerative braking circuit and stop velocity control scheme with jerk limitation. The decelerating velocity reference is designed to enlarge the regenerative energy. Some experiments are performed to verify the effectiveness of the proposed system.

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This paper describes a fuzzy driving control scheme of power-assisted wheelchairs for the low power consumption. The proposed fuzzy system suppresses the maximal assisted torque and keeps the low torque for inertial driving based on the human input torque and driving velocity information. Long distance driving experiments comparing with the manufactured wheelchair shows the effectiveness of the proposed control system.

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Originally, a path-generating regulator (PGR) was a control method for two-wheeled mobile robots to converge a position and a heading angle of a vehicle to the origin of a coordinate frame. The heading angle is controlled so as to align the target heading angle. The target heading angle is the tangential angle of one of the path among the path function group. In the past, we extended the PGR to car-like robots and take care of the singular points, due to both of the mechanism of a car-like robot and the control method. However, the environment with the obstacle is not considered in PGR. In this paper, we propose a method of obstacle avoidance by modifying the target heading angle. And, we confirm avoidance behavior by simulation.

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This paper presents a novel personal robot assisting transportation to support active human life. The personal robot can bring the luggage and follow the human being automatically. Therefore, the robot encourages the elder people to go to outside for shopping, airing, and visiting friends. The robot should achieve both small footprint for coexistence in human community and high traveling performance to follow the human being. For achievement of these requirements, active posture control for roll and pitch angle is an essential technology. In this paper, the structure and control approach for posture control is proposed to realize the following the human being. The effectiveness of the proposed approach is verified by experiment using a new prototype robot.

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Tsukuba Challenge is the technical challenge of autonomous mobile robot, which can travel in the real and usual city pedestrian and park environment, where domestic people are usually using. The first stage of Tsukuba Challenges is held in 2007-2011, and they have promoted the technical level of practical mobile robot systems. Succeeding to them, the second stage of Tsukuba Challenge is planned from 2013. This paper explains the discussion on the practical subjects which should be achieved by the experimental mobile robot systems. And, show the defined task for the robot in the second stage of Tsukuba Challenge.

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This paper performs the mobile robot navigation system using the simplified hybrid map. The simplified hybrid map consists of a topological map and a metrical map. In this paper, The place of a metrical map performs a road surface detection, and the place of a topological map performs the SLAM algorithm based on image matching and FastSLAM. However, it is not enough to achieve autonomous navigation using the map. Then, in this paper, additional information for robot navigation is recorded to the simplified hybrid map, and It considered as the navigation system using the simplified hybrid map.

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The purpose of the research is to create a radiation map. Radiation is harmful to the human body so we must avoid radiation as much as possible. A radiation map enables to avoid the high radiation point for human. However radiation measurement needs to stay for a few minutes at the point of measurement so radiation measurement a large number of points is difficult. Therefore, we aimed to create a radiation map automatically by using a mobile robot. In this paper a Two-Step measurement is proposed aimed to create a radiation map using a mobile robot.

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Conventional researches on human-robot collaborative motion, almost in its entirety, always emphasize on safety and therefore prioritize humans. However, in a congested area this approach will result in a highly inefficient robot motion. This paper proposes a method wherein, we utilize contact and shoulder turning behavior to induce a desired trajectory on a passing human. Through the use of contact and shoulder turning we try to prioritize the robot. We analyze the effectiveness of our proposed system through simulations. The results of the simulations show that the above method can be realized to produce a safe and highly efficient motion.

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