First, we formulate the system dynamics of a 2-DOF robot arm with contact forces and friction forces between the robot surface and the object reproduced by the LuGre friction model. Both the static and dynamic friction forces can be specified as a single differential equation according to the method of the LuGre friction model. Second, we design a two trajectory tracking control system in order to manipulate the position of the center of mass of the object. The first control system is inverse dynamic control, the second is sliding mode control. Finally, we compare the control performance of two control system in terms of average error norm and average input power. The validity of the proposed method is investigated by numerical simulations.

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In daily life, there are many bottlenecks such as narrow passages, gaps between objects and entrances to rooms. At the bottlenecks, humans go through by giving-way mutually, and it is necessary for robots working in daily life to give way. The purpose of this research is to develop the model capable of generating the give-way behavior by estimating a pedestrian intention. In this research, we introduce hierarchical intention to Social Force Model using quantum information theory.

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This paper deals with a novel manipulating scheme for a passive object using an active plate. In this context, a tumble doll is defined as the object. Then, the object and active plate's motions are designed to be cyclic. A state vector composed of the object angle and angular velocity is defined, and the cyclic motion is expressed as a nonlinear discrete system. Fixed points of the state vector are searched for in the designed cyclic motion. Stability analysis around the fixed points is conducted using Poincare map. Finally, the experimental results verify that the object's angle can be manipulated with the designed cyclic motion using the plate.

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This paper presents a method for scheduling carrying tasks of a robotic arm using a contact transition graph. This method generates a task sequence to achieve the objective work-environmental state focused on the contact state of an environment. Objects in contact state are moved together as an object is carried. A task sequence of a robotic arm is determined by solving a shortest path problem of the state transition system of the contact states of work environment. The motion trajectory of a robotic arm is generated by planning a trajectory based on the task sequence.

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In this research, we consider a posture control problem of the torque unit manipulator under friction condition. The torque unit is a module which consists of an electric motor and a reaction wheel. When the first joint in the base side is free, it becomes difficult to control the planar manipulator. First of all, as an easy problem, we consider a posture control of a planar one-link torque unit manipulator which is equipped with one torque unit. We compare the stability of the planar one-link torque unit manipulator with that of a conventional planar one-link manipulator which joint is actuated. We also compare their energy comsumptions in the posture controls. Then, we consider a posture control problem of the two-link torque unit manipulator.

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A redundant manipulator is also uncontrollable at the singularity. In our previous work, the Singularity-Consistent (SC) approach has been applied to both the column-augmented Jacobian and the augmented Jacobian for redundant manipulator to control stably around the singularity. However, these approaches introduce an inner obstacle related to non-redundant motions. Thereupon, the SC approach has been applied pseudoinverse Jacobian. Although the inner obstacle disappears, SC pseudoinverse Jacobian cannot pass/escape the singularity. The operability around the singularity becomes poor. In this paper, we propose a combination of a normalized pseudoinverse Jacobian and the SC augmented Jacobian to achieve proper performance around the singularity.

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The calibration-free visual feedback control method had been proposed in 2012 and the experimental validation of the proposed method was demonstrated by using a 3-DOF robot arm. Furthermore, the control method applicable to 6-DOF robot arms was proposed in 2013. This paper experimentally investigated the validation of the proposed method for 6-DOF robot arms. Through experimental results using a 6-DOF robot and a stereo camera set, the usefulness of the proposed method is demonstrated.

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In this paper, we propose a position planning method for mobile redundant manipulator. In order to continuous inspect facilities of infrastructure, it is desirable that autonomous image collection of surface condition using robots. Because of the wide movability and high redundancy, we chose a mobile redundant manipulator. To collect surface image of complicated facilities effectively, position planning of mobile redundant manipulator is very important. We propose a position planning method based on movement cost. Under the condition of uniform shooting, moving positions are determined by trial-and-error. Simulation results show the possibility of autonomous image collection for surface inspection.

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Sweeping robots such as floor cleaning robots uses probabilistic reactive motions to cover wide area in unknown environment. It has been believed that the probabilistic motion primitive is necessary in addition to some deterministic motion primitive like wall following and parallel motions. The paper investigates the sweep motion in given rctangular work space by only a deterministic motion. The resultant weep motion shows chaotic characteristic according to consition of motion parameters. The motion is similar with the one by probabilistic reactive motion primitive. It means a possibility of efficient weeping motion by simple deterministic motion primitive.

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The purpose of our research is to improve robot motion ability not depending on only actuator power. In multi-link systems such as humans and robots, energy is transferred between links. That is called the kinetic chain. Humans realize high motion ability not depending on only actuator power using the kinetic chain. In this paper, we describes the results of analyses of relationship between energy transfer in robot links and motor commands.

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A daily assistant robot which performs tasks in living environment should be interrupted by human at any time in order to prevent failure of task execution and improve robot's behavior. This paper provides the model of a preemptive robot action management system which is integrated with an existing distributed robot control system. This model consists of three modules which is called when a human interrupts a robot action: a preemptive task management, dynamic action state management and motion modification.

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This paper describes a trial educational program that combined the "Jigsaw method" with the "PBL (Problem Based Learning)". In PBL program in Ibaraki KOSEN, there are some problem caused by a difference in skill level between "Robot club students" and "Non-robot club students". I tried to solve these problems, so I combined the Jigsaw method with the ordinary PBL and gave some small lectures to "Non-robot club students" based on Jigsaw method. As a result, 4 groups completely succeed in assigned problem about a line trace robot.

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In our college OPUCT, we started a practice using a project based learning method for creative design and manufacturing since 2009. The practice accepted the fund of a good practice from Japanese Ministry of Education from 2009 for three years. We still practice the curriculum because it is highly effective way of teaching a creative design and manufacturing. Furthermore, we started an education for disaster prevention with another 6 technical colleges in the Kinki area from 2012. In additional, we integrate that practice into a viewpoint on this disaster prevention this year. In this paper, we introduce our activities of disaster preventions and practice for creative design and manufacturing. We also describe a vehicle competition that is useful in disaster as the result for the integrated practice.

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Recently, a small-sized humanoid robot is often used by education. However, as for their most, a sensor is not put on. It is difficult to be installed in order that a sensor records data to a small-sized robot. Then, we already developed the ZMP sensing device which a robot could install. Furthermore, we developed the motion analysis system of the robot by the image. By using this system, we got possible to do the measurement of the motion of the hands and feet which ZMP sensing device cannot measure. Therefore the student can perform an experiment more effectively.

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We are developing mechatronics education program using line tracing robots which are controlled by microcomputer. This program is applied to the new students as an introductory course of engineering experience. The class consists of hardware, software development of the robot, and its evaluation. We strongly recommended to the students to develop a new robot with original features. For examples, at the beginning of the class, we invited our OB and had a lecture about the importance of originality. As a result, more than half students developed various robots with original features.

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We develop a block type tool "P-CUBE" supporting programming education for visual impairments. P-CUBE enables programming of the mobile robot without operation of the personal computer. P-CUBE consists of programming blocks and program mat. A sight impaired user can create the program of the mobile robot by laying out programming blocks on the program mat based on algorithm structure. The layout information of the programming block is translated to program language via program mat and PC. First, we report the system configuration of P-CUBE and programming workshop with P-CUBE for visual impairments. Furthermore, we produce improved designs of the programming blocks for solving the problem at the workshop.

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Since 1988, the Department of Digital Engineering at Numazu National College of Technology have introduced a Project-Based Learning (PBL) with Micro Intelligent Robot System "MIRS" into the curriculum for the education of system development process. We are intended to provide a place of learning "process of system development" and "making education as a creative education" through the development of robot. In 2009, a new robot platform, which is provided for students at the beginning of this PBL program, was developed in order to improve the technical factors of robot system, and at the same time, increase students' motivation for learning. In this paper, we reported practice of PBL Program developing MIRS in 2013 and the efforts of four years. Features of 2013, is that the students to study the needs of society, we have proposed a new competition. A further improvement of student attitudes and motivation for making things up will be an issue in the future.

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We report on the engineering design class "Engineering Practice 2" in 2013 that opened a course in the department of electrical engineering, Shibaura Institute of Technology. The strategy of this class is to design and develop an autonomous inverted pendulum robot by oneself to improve the engineering design ability. The mechatronics educational material was improved to elaborate how to develop a control circuit equipped with the H8 micro computer. The questionnaire's result that Engineering Practice 2 was carried out in 2013 provided us the effectiveness of improvement and potential of this class.

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Classes using the microcomputer are performed in Kitakyushu Institute of technology (Department of control and information systems engineering). There are two classes using a microcomputer, however, those classes use different microcomputers. To solve the problem, it is aimed at the development of the microcomputer module unified standard in this study. In this study, we used PIC32MX to develop the microcomputer module. In this paper, we studied how to control of the crane robot with 'PIC32MX'. In addition, we carried out design of microcomputer module using PIC32MX.

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Direction of education use of robot was discussed. The environment of education, pattern education and design education were explained. I defined the robot and made a table of robotics core and the expectations of robot were explained. Direction of education use of robot was design education and application in society. Robotics has connecting force.

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The Rescue Robot Contest Seeds (ResCon-Seeds) is a local and small-scale robot contest which deals with major disaster as the subject in order to educate elementary children about robotics technologies. We proposed a new workshop in which we have children build hand modules to provide additional functions to the robots. This method has an advantage of saving the assembly time and cutting down the costs of teaching materials. and brings effects increase frequency of offering educational programs in robotics.

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For high school student education, a multi-leg walking robot model MINITAN Z that is small and reasonable and can be controlled from PC is developed. There are points of study that are hard to understand for novices in walking robot: static balance and kinematics. As a teaching material that supports the points, the robot has four legs, can walk keeping static balance, be controlled simply and have legs that can be operated as a robot arm in the air. 5 walking robots and 5 single leg mechanism based on the model are manufactured. They are used in a workshop education and evaluated by questionnaire survey.

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The purpose of this study is to build an educational program in which students can develop an intelligent electric wheelchair that meets society's needs. In order to keep the costs and necessary time under control, we will introduce a wheelchair platform that supports the students' development work. The platform uses a commercially available wheelchair as its base. A computer on the wheelchair can accommodate USB ports, a camera, a digital compass, a GPS receiver, a laser range finder, and many such sensors. Students build software by combining control-oriented library functions provided by the instructor. The operating system of the computer is Microsoft Windows 7, and the software is built in Microsoft Visual C++.

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Elementary school and junior high school students have recently begun to learn programming. Students who are taught how to create programs are often required to use the interface of a personal computer. This method keeps visually impaired and younger children from the opportunity of learning programming because their operations depend on visual information by using a display a keyboard or a mouse. In an attempt to address these problems, we have developed P-CUBE, a new programming education tool for visually impaired that does not require the PC operation. In this paper, we report a programming workshop for the visually impaired using P-CUBE.

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Lessons about robots for junior high school students were opened in summer. In the lessons, students made robots to achieve a certain objective in collaboration with a team. In this paper, the contents of the lessons and the questionnaire are shown.

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Chemical Plume Tracing(CPT), locating the distant odor source in a turbulent environment, has been studied for robotic odor source search. However, solving CPT problem is not easy because structure of plume in the air is complicated. Therefore we focus on the behavior of silkworm moth. Silkworm moth, bombyx mori, is one of the insects that have the ability to solve CPT problem. To measure their CPT algorithm, we propose the behavior observation untethered system, 3-DOF servosphere and it can enable us observe silkworm's natural behavior. We also developed simultaneous estimation system of stimuli input. In this study, we can analyze interaction between CPT algorithm and stimuli input.

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Animals are able to cope with tasks adaptively despite unexpected situation while robots can perform in limited situations. Robot controlled by electromyogram enable us to investigate mechanisms of animal's adaptability, but we have to obtain the rule to convert electromyogram into actual behavior in real space to realize such robot. We construct experimental system which can measure both behavior of walking silkworm moth and electromyogram recorded from a leg of the silkworm moth simultaneously, in order to reveal that transformation rule. Leg movements were recorded by high-speed camera, and converted into relative angles observed by silkworm moth, using image processing of video of behavior.

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In the manufacturing industry, sports, and care nursing, conventional skill education is inefficient because it has been conducted face-to-face and skills have not been elucidated. In order to solve this problem, effective service of skill education is necessary. We focused on bed care motion for patients who laid down on their beds and are aiming to develop a new skill education service for care motion which can prevent the outbreak of lumbago. In this study, based on the expert skills which were elucidated in our previous research, the motion was analyzed using three dimensional musculoskeletal model how different motion between experts and non-experts. In particular, we calculate hip moment with measured data from expert motion and non-expert motion because hip flex moment is related to lumbago. Our results show expert motion reduces hip moment compared to non-expert motion.

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A human foot has a complex structure which consists of a flexible flesh and many muscles, tendons, ligaments, and bones. The complex structure is supposed to contribute to efficient and stable bipedal locomotion. Detailed behavior of the foot complex during walking, however, is not well unerstood. We built a musculoskeletal gait simulator driven by pneumatic artificial muscles in order to solve a mechanism of a human gait. We measured ground reaction force of the musculoskeletal gait simulator during the stance phase by using a force plate. This gait simulator's vertical ground reaction force has two high peaks like a human's.

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The plantar area of the human foot is larger than that of quadrupeds' foot, and it contains a large number of sensory organs. Thus, such a foot structure plays a crucial role in extracting "rich" sensory information for the generation of adaptive walking in humans. Here, we propose novel central pattern generator (CPG)-based control of a bipedal walking robot by exploiting plantar sensation. To effectively exploit plantar sensory information, we redesign the local sensory feedback to the CPG model that we previously proposed for quadruped robots. The simulation results indicate that the biped model exhibits a remarkably robust walking ability by exploiting the plantar sensation according to the current walking motion.

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In this study, to the development of the visual system of tomato cultivation robot by using a Web camera is an inexpensive image input device and OpenCV is an open source. Was the recognition in the binary process by the color data as the target petals, fruit, a auxiliary bud. In addition, I examined the noise removal method that has occurred. At that time, recognition narrowly accurate recognition range is difficult to auxiliary bud. So I examined the object detection by machine learning. As a result, I was considered to be the detection of possible side Buds by machine learning.

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The objective of this research is to develop an end-to-end system of high-resolution digital map archiving. In the system, multicopter, Cinestar6, is used. By using multicopter, we perform low-altitude photography and collect some set of videos. We extract the videos into frames and perform feature extraction to generate feature points. Then, the image alignment based on the feature point is performed to generate panorama image. Last, super-resolution algorithm is used to increase the resolution. To see the effectiveness of the system, we applied to citrus tree breeding problem. The task is to recombine the DNA to breed new varieties. By using this system, each plant could be tracked, observed, and analyzed to get relevant the information for the expert.

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The purpose of this study is to develop a power assist machine that can assist the user's arm to reduce burden on farm workers. The assist machine consists of a linkage mechanism in order to use a single actuator. In this paper, we used a screw feed mechanism and a worm gear mechanism as a deceleration mechanism having a self-lock function. As a result, it is possible to keep the work posture of the upper limbs without controlling an actuator. The effectiveness of the proposed two kinds of power assist machines is verified by the result of the experiments.

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The purpose of this study is to develop a wheel-type weeding robot in a paddy field. The weeding robot has a capacitive touch sensor to detect the rice plants, microcomputer and battery. The function of the sensor that is mounted on the weeding robot can detect rice plants and cannot be affected by water. In this paper, we design and develop two kinds of autonomous weeding robots. Kemp's linkages is used to keep the distance between the sensor and the robot main body. The effectiveness of the developed robots is verified by the preliminary experiments.

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A Field Server, wireless sensor network system for agriculture, provides useful and practical monitoring in a crop field. To achieve more advanced and smarter sensing, we have proposed a robotic Field Server monitoring target data widely and closely in a crop field. The robotic Field Server consists of a conventional Field Server with sensors and wireless module for smart monitoring, a locomotion unit for moving in target fields, and a handling actuator unit for flexibly measuring the targets. The robotic Field Server supported by fixed-type Field Servers is controlled at a remote site via the Internet. We conducted an experiment to collect detailed data of many target fruits in a pear orchard with the robotic Field Server moving around the field, and clarified the potential and effectiveness of the proposed monitoring system.

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A plant factory is an all-year-round plant cultivation system under a controlled environment. It facilitates very efficient and stable production of vegetable that are chemical free, fresh, clean, and nutritious regardless of season or geographic location. The current drawback of the plant factory is high running cost and capital investment of huge amount. These are a major obstacle that spread to the general of the plant factory. Therefore we try to develop more compact and lower cost plant factory for home-use. In order to verify the performance, temperature control and lettuce cultivation were carried out. The result, it was shown good characteristics.

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The aim of this study is quantifying and modeling know-how about the cultivation of the mandarin orange so that even an amateur may perform the sophisticated work for cultivating the mandarin orange. Generally speaking, it is said that choosing the best time of watering is important for growing high-quality mandarin orange. Although it is very difficult to decide a timing of the watering, an expert farmer usually decide it by watching whether a fruit tree is energetic or not. It is said that such decision is very intuitive or that the decision would depend on watching whether the leaves are withering up or not. In this work, we develop a sensing system for cultivation of high-quality mandarin oranges that can measure the condition and the growing power of the tree. In this report, we present the overview of the system and its preliminary observation result.

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Recently, blueberries are becoming popular as functional food, and the cultivation area continues to increase in Japan. In America, a blueberry harvesting machine which shakes down blueberries is introduced. However, to harvest sweet high-value bluberries, it is necessary to pick by expert farmers' hands for estimating ripeness of each berry at the time of harvest. Therefore, we think that a robot which can pick ripe blueberries one by one like expert farmers do is necessary. In this paper, we propose a robot arm approach method of preventing the robot's end-effector from colliding with obstacles based on 3D vision and imgage processing, and we build a foundation of an automatic ripe blueberry harvesting system with a wheel moving arm robot.

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In this paper, the authors proposed the weeding robot system whose position is given from two single-point GPS receivers. One receiver is included in the robot and another is in the base station, and the position of the robot is given as the relational coordinate according to the base station. Then, the precision of the measurement is increased because the affection of the noise is cancelled. The efficacy of the developed system is confirmed by the measurement experiment at outdoors.

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In the present paper, development of an automatic harvester which harvests spinach for eating raw is considered. It is hard challenge to develop the automatic harvester for spinach because those leaves and the stem are soft and easily to get bruises, and so there are not any harvesters which are widely used in the farm. In contrast, a test model of the harvester is developed by our research group and it is shown that automatic harvesting for any types of spinaches is possible even if there is no chine and interrow space in the farm field. In the test model, the root of the spinach is cut by a root-cutting blade which moves in soil, then the root-cut spinach is collected and transferred to the upper position from the ground by conveyors. The effectiveness of the developed harvester was verified by several field tests.

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Nowadays in Japan, consciousness for food safety is increasing. Therefore the vegetables made with organic farming attract attention because they are safer. However, farmers must perform extensive hand weeding in daily farming for sustaining organic farming. The weeding work hours of farmers in herbicide-free farming is five times longer than the farming uses herbicides. The autonomous mobile robot in this study helps weeding in the organic farming. The stereo camera with pan-tilt mechanism is equipped on the robot. The operator detects harmful herbs, and remotely operates the robot arm for weeding.

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In recent years, consciousness of people is increasing about safety of foods. The safety of the rice which we usually eat is gathering attention too. It is said that organic farming is one of great farming methods because it does not use weed killers and chemical fertilizer and so on. However, in organic farming, farmers must remove weeds with their hands. It is a heavy labor for them. Therefore, in this study, we have developed a weed suppression robot which helps organic farming. We designed a robot hand, a mechanical brushing device attached at the end of the robot arm of the autonomous mobile robot, which suppresses growth of weeds. The robot is controlled by remote control from the outside of the rice field. We have verified the effectiveness of weed suppression through indoor rice field experiments.

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In this study, we develop the work auxiliary carriage for the transport of crops after pick up in the greenhouse. In order to develop an carriage can introduce easily, We develop a system for steering analyzes the images from camera mounted on the carriage without any special construction and equipment in greenhouse. We intended for strawberry hydroponics greenhouse especially. In this paper, we describe in detail a method of image processing for determining the steering direction of the carriage especially. To demonstrate the effectiveness of the proposed method, we confirmed straightness using carriage for test by running test.

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Though medical technology has made a great progress recently, there are still many diseases difficult or impossible to cure. One of the problems is late detection of the diseases. We propose palpable endoscopes with the pressure sensor to develop the early-detection of diseases. Cancer tissue is known to be harder than normal tissue. In this study, In order to develop the palpation technology, we made a biological model of organs made of jelly. At first, we investigated whether jelly had young's modulus compatible with organs. The jelly with 15 % of concentration and 20 C of storage temperature was found to be appropriate. Next, we made the biological model of a cancer embedded in a normal tissue by using the jelly and then measured the young's modulus. We believe the proposed model is readily applicable to develop the next generation palpation technology.

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Highly sensitive, wide-measurement-range compact load sensors are desirable for various applications. A load sensor using an AT-cut quartz crystal resonator (QCR) has superior characteristics such as, high accuracy, improved strength under compressive stress, long-term stability. However, a retention mechanism is required to firmly support the QCR because the QCR is easily broken by stretching and bending motions. Conventional machining processes are not suitable for further miniaturization of the sensor. Even if the retention mechanism were miniaturized, the assembly process is complicated. In this paper, we propose a novel design and fabrication method for a load sensor using the QCR. Using microfabrication and bonding, the assembly process was simplified. We demonstrate the feasibility of a miniaturized QCR load sensor whose volume is 24.6 mm^3 . Sensitivity of the sensor was 1458 Hz/N. We improved the sensitivity and stability of the sensor; the fluctuation was 0.06 mN over a period of 3 min.

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We developed a bed-style haptic display that provides weight sensation to large-area of the user's body. The system is composed of motors, belts, cushion and quilt to press and swing the user lying in bed. It is one type of the whole-body haptic interface, characterized by the presentation of low-frequency, multi degrees-of-freedom force. The system can enrich audio visual experience by several ways, such as expressing horrific ghost sitting on the user as an entertainment contents, or presenting remote relative's existence as a tele-communication tool. Overall, the system change the bed into a new medium in which immersive contents are truly presented immersively.

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This paper presents tactile presentation method using underwater electrical stimulation, primary for the purpose of in-a-bath entertainment. As a first step for underwater electrical stimulation, we investigated localization and effect of polarity of the stimulation. We found that in contrast to previous studies, anodic stimulation elicited stronger sensation than cathodic stimulation in underwater electrical stimulation to the forearm. Furthermore, we found that the direction and rotation can be presented by underwater electrical stimulation.

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We have developed a system composed of an electro-tactile display and distributed pressure sensor underneath. The pressure sensor detects finger pressure distribution, and the electro-tactile display presents tactile sensation in accordance with the pressure distribution, so that local "force-feedback" is achieved at each electrode. In this paper, we utilized this system to express softness feeling. The tactile stimulation is presented just at the edge of the finger contact area so that it enhances expansion and shrinking of contact area when the users press and release their fingers. Experimental result revealed that proposed algorithm surely increases subjective softness.

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This study proposes a noncontact method to provide thermal sensation. It was observed that the plate is heated when slits on a plate are exposed by a high-amplitude ultrasound. There is a possibility to provide thermal sensation remotely by utilizing this phenomenon. Users' motion is not restricted by wires etc. Furthermore, arbitrary positions can be heated because our ultrasonic device has an ability to move a focal point of high-amplitude ultrasound. This paper gives an explanation of this phenomenon and experimental results.

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