A 3D environment model is important for tasks of autonomous mobile robots. In this paper, we propose a method for 3D environment modeling based on structure from motion using an omni-directional camera installed on a mobile robot. The method extracts and tracks feature points in an omni-directional image sequence to get corresponding points in image pairs taken during the movement of a robot. The relative relations of camera positions and orientations are estimated by the positions of the corresponding points. With these relations and image coordinates of the feature points, 3D coordinates of these points are calculated by triangulation. The individual measurements are integrated by scale matching. By using 3D Delaunay triangulation, triangular meshes is constructed. The method makes the triangular meshes compatible with the physical shape from texture information of images. By texture-mapping, a 3D environment model is generated. Experimental results showed the effectiveness of the proposed method.

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The paper presents a new convergence calculation method for the Normal Distributions Transform (NDT) scan matching using high resolution grid map. The proposed method enables to find corresponding point, even if it is out of the reference scan area. The scanning area is enlarged by modifying the eigenvalue of normal distribution. In the high resolution grid map, the point data often become sparse and the normal distribution of the reference scan cannot be built. To solve this problem, the reference scan is enlarged by combining with neighboring reference scan. These methods improve the accuracy of the matching calculation in the high resolution grid map.

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There are many navigation techniques for robots. It requires large cost to make a map for each navigation method since the required map is method-dependent. Therefore, in this research, we propose the 3D Environment Map (3DEM) that is able to generate any maps for specified navigation techniques. For example, the 3DEM can produce a Ceiling Map, a VSS (View Simulation System) for View Sequence and a Human Navigation Map. This paper describes the concept of 3DEM and a method to make it for Indoor Environments. Moreover, we demonstrate a result of generating a Ceiling Map from a 3DEM.

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Position estimation is very important theme for autonomous mobile robots. In this paper we propose new global positioning sensor system. Its feature is that the system is structured by only one ultra small-sized Laser Range Finder (laser based SOKUIKI sensor) and the sensor detects only plural reflectors which are installed in environment. The sensor compares the map data, which is memorized in the sensor with detected data, then it estimates its own global position for output data. For this purpose we considered algorithm and confirmed its validity by computer simulation and experiment in real indoor environment.

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In this paper, we present an approach of extracting high-integrity feature points in stereo images for calculating visual odometry for outdoor robots equipped with an inexpensive stereo camera. The robot pose is estimated by bundle adjustment approach. Bundle adjustment helps to reduce the error significantly. As a result, it is shown that successful extracting high-integrity feature points was done.

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Gyro-based odometry is a robust and easy-to-use localization method for mobile robots. However, the Gyro-based odometry for tracked vehicles has difficulties to estimate its exact localization because of track-terrain slippage and gyroscopes' bias-drifts. To solve these problems, we propose an extended 3-dimensional odometry method for tracked vehicles based on multiple internal sensor fusion. The proposed method consists of slippage- compensation using encoders and gyroscopes, attitude correction using an acceleration sensor and gyroscopes' bias value update. Finally, a performance test was carried out in real environment to confirm a validity of our approach. In this paper, we introduce the three-dimensional localization method by extended gyro-based odometry and report the experimental results.

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In this paper, we propose a method of robot motion control for sidewalk navigation in outdoor environment. The robot moves using data of LRF. In advance, the robot is provided the map which has the position data about turning points. GPS and Odometry are used for self-position acquisition. If the robot comes to turning points, it moves based on this map. This method which we propose is applied to our robot. We clarify usefulness of this method through real world experiments.

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Recently, mobile robots like cleaning robot and security robot have been studied. When such mobile robots are operated, it is necessary to generate their trajectory automatically. In recent years, real-time generation of a dynamic obstacle avoidance trajectory is becomes possible by advance of computer. In this paper, the system which generates the target trajectory avoiding obstacles in the indoor environment automatically by the real-time optimization is constructed. The effectiveness of the proposed system is verified through the experimental system using the omni-directional robot.

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It is well known that CVT is effective for fuel economy. We proposed the wide range CVT (WRCVT) which enables gear ratio from forward to reverse by the combination of half toroidal CVT and differential gear. This WRCVT is installed on a test vehicle with newly designed on-board controller. The integrated accelerator signal was the reference to the WRCVT because the revolution speed of the engine should be kept constant. When brake switch is turned on the reference is changed to the measured wheel speed signal to prevent mismatch between transmission gear ratio and actual vehicle speed.

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A new differential gear mechanism is presented in this paper. By using this mechanism, it is possible to control the rotation of the target axis without any effect on axis passing through, and then because of easy to produce, ATV with Differential Control System is manufactured, i.e., add the differential force from the motor to the driving force from the engine without any interference and output from wheel.

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Recently, mobile robots are expected to be used in various fields. Recognition of the self-position is important to move autonomously in the environments. Dead reckoning is used widely as the way to recognize the self-position. However, the localization error is unavoidable in dead reckoning. In this paper, we propose a method for improving the precision of dead reckoning by predicting its localization error by using the AR model which is a time series analysis model.

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This paper describes the developed an autonomous running method for a wheeled robot which is able to run on a slope plane in uncertain three-dimensional world including a spiral slope. The developed new robot is an autonomous type which is able to run on two wheels and mount an ultrasonic sensor and a PSD (Position Sensitive Detector) sensor. The robot can run to the destination while presuming three dimensions and the self-position with a dead reckoning and recognizing the environment in an uncertain 3D world including the slope.

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This paper proposes a new vehicle type mechanism which has 4-Wheel-Drive Omni-Wheels with 4-Wheel-Steering. This mechanism is a superset of conventional Omni-directional vehicle and some car type mechanism. Then with some DOF fixed, the mechanism can be applied many conventional driving methods. Steering and driving characteristics of the vehicle is illustrated with geometrical analysis. A straight driving method with non-step gear ratio by symmetric steering and a turning method by difference of driving speed are tested. Experiments are held with a vehicle model and some difference between the analysis and experiments caused by dynamic effect such as driving or cornering force.

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A dynamic skating method by cyclic leg extension and contraction is improved by introduction of dwell time to the leg extension trajectory. 7th order polynomial function is used to have dwell time without discontinuity. Swing motions in frontal plane are simulated based on an equation of motion of inverted pendulum and a condition of conservation of angular momentum at collision by switching support leg. And it is shown that limit cycles exist various cycle of leg extension while phase at switching support leg changes to match inverted pendulum motion period to cyclic input period. With dwell time, limit cycle exists for longer cyclic leg extension period and it is expected to lead longer skate distance for one step.

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In this study, we have been developed an autouomous running method which run a wheeled mobile robot with a one-eyed camera and by using a rangefinder method by a line laser to a goal while avoiding obstacles moving in uncertain space including a narrow road.

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The navigation task is applied to the potential function that we propose and it verifies it by the simulation. And, the domination of this method is shown compared with other method.Moreover, the thing that retreated by changing the operational expression of the potential function became possible.As a result, it comes to be able to innovate the sensor that was not able to be used in a current specification. However, the influence on the navigation according to the introduction of the action decision is uncertain. Therefore, the influence on the navigation by having increased state newly as give the evasive action width by backdown and can do the best action is verified.

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The proposed quasi-minimum time trajectory for a mobile robot is obtained as follows. First a global quasi-shortest path is generated by Path Shortcut Method on a provided floor map. In the navigation step, a local quasi-shortest collision-free path is obtained by the method and described as a spline curve. Then the time optimized trajectory is generated by the idea of time scaling. An idea of self-positioning with a range sensor is also proposed. The autonomous navigation is effectively executed by the proposed algorithms.

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In resent years, the bicycle-type unmanned vehicles have already been studied and developed. The goal of this research is to develop a bicycle-type vehicle can run on the rough road in forest. As a fundamental research, we have developed the control system which can balance and run our vehicle on the flat road.

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The research of image-based control for nonholonomic mobile robots is a recent topic of mobile robots. There are few researches about image-based control of mobile robots with central catadioptric cameras. A central catadioptric camera is very effective to keep target objects in the camera field of view because of its wide area view. In this paper, a new image-based path following control method for a nonholonomic mobile robot with a central catadioptric camera is proposed in the image parameter space. It is confirmed by indoor and outdoor experiments that the designed system has high performance and robustness in real world.

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We research the mobile robot navigation system by using one laser source. We confirmed that we could navigate the mobile robot by using laser navigation system and described the basic features of this system. However, when the navigation speed was fast, it was difficult for the robot to follow the laser spot. We found that we needed to change the scanning speed, synchronizing it with the acceleration and deceleration of the mobile robot to realize the smooth navigation. In this paper, we examine the device configuration and the simulation result to scan the laser smoothly.

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This paper addresses a new technique of a maneuvering assist to adapt to human operation. When we maneuver the robot, the collision or accident is occurred by our careless mistakes. For prevention measure, many assistance functions have been suggested before now. However, those functions crossly preclude that we want to do, because of attempting to avoid that. In this paper, we suggest new system that assists maneuvering the robot without operator's notice. Finally, the technique is verified by several simulation experiments.

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Service robots are desired safety and movement stability in the symbiosis space. Driving module of inverted pendulum type mobile robot is suitable for the small space and high performance of mobility. This paper describes about the attitude stabilization of inverted pendulum mobile type robot for the trouble of power management or the control system. It consider about effectivity of redundant control system and the center of gravity from a result of numerical simulation.

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In this paper, we discuss the control of 2D inverted pendulum as an application of a platform robot. The platform robot called "WITH" was developed in our laboratory, and the robot is able to do omni-directional movement. We present the effectiveness as the platform robot by controlling the 2D inverted pendulum.

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The application of four-wheel rover to the ground test of jet engine is presented. Main role of rover in this test is data acquisition around the engine and the surveillance of engine and measurement devices. The load capacity of new rover is increased up to 8 kg and its upper deck is designed to be flat, so that rover can be equipped with such devices as laptop computer and surveillance camera for multi-purpose measurement. The use of wireless LAN enhances the data communication between remote-control rover and local computer in the operation room, such as live video, control command and measured data.

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Recently, various mechanisms have been developed combining linkage mechanisms and wheels. Especially passive linkage mechanisms and small wheel type robots are proposed, because a wheel type mobile mechanism has difficulty on the rough terrain movement. In our research, a 6-wheeled mobile robot employing the linkage mechanism has been developed to enhance maneuverability, and achieved climbing over a 0.20[m] height of bump. We designed controller using neural network for high energy efficiency. This controller has same performance with PID. In this paper, we propose environment recognition system for wheel type mobile robot on rough terrain environment. This system consists of multiple classification analyses. We compared with some methods.

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A wheeled mobile mechanism with a passive and/or active linkage mechanism for rough terrain environment is developed and evaluated. In our previous research, we developed a switching controller system for wheeled mobile robots in rough terrain. In this paper, we focus on the decision of controller parameters using hyperplane of adjusted neural network. Our proposed controller shows almost same performance of adjusted neural network controller in the experiments of the climbing over the stairs, even though that controller consists of less parameter than neural network controller. And also, that controller shows better performance than well-tuned PID controller.

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Wheelchair has become popular in the past several years. And electrical wheelchair that has battery, casters and motors is developed. On these wheelchairs, casters and driving wheels are slipped and induced slip angles. Cornering forces are induced by these slip angles. And these forces cause the wobble and restricted forces. For this reason, it is difficult to control the wheelchair as operator's directed. In this paper, we focus the effects of cornering forces by casters and slip angles. We consider that the effects of casters and slip angles to control the wheelchair as directed.

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This paper describes a novel technique to reduce planning time and memory using precomputed search trees with steering sets. One property of precomputed search trees is that collision checking is not greatly required during growing the nodes. Precomputed search tree is one of the idea of reducing planning time however it's a time-memory trade off. We present a new path planning with precomputed search tree using pruning based on a rule of memory constant.

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For mobile robot at outdoor atmosphere, the robot has to avoid any obstacles, e.g. human beings, trees and any construction. We developed a obstacle avoidance system using laser range finder and ultrasonic sensor. The base algorithm is potential method. We added a strategy for avoid local stable balanced point where the robot cannot escaped. To certify this algorithm, we tested this algorithm with simulation and experiment about many cases.

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This paper describes a method for obstacle detection and obstacle avoidance for a mobile robot using SOKUIKI sensors in outdoor environments. Road shape 3D map is constracted by SOKUIKI sensors. Obstacles are detected by unevenness of the height on the road detected by SOKUIKI sensors. We remove the discrete, low unevenness from 3D map to prevent the misrecognition of fallen leaves. Data of obstacles are stored in a ring buffer to store all the measurements in the last 7 seconds. We define a "free space cuboid" to represent possible "obstacle free space" where the can pass through. Each cuboid has a priority number which is checked from highest to lowest priority in order to perform obstacle avoidance.

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We developed the autonomous mobile robot system using GPS. When the operator inputs the goal point by GPS coordinates data, the robot go straight using GPS data. In this system, the robot compares the present direction and progressive direction, and controlled the angle to zero. We implemented the system by use of wheelchair and had the outdoor experiments. In outdoor experiments, we confirm the validity of this system.

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Some of conveyance tasks of the mobile robot are used to improve the efficiency of the production system. If the induced inertia force and torque should be bigger than the maximum static friction force and torque, the carrying objects begin a slipping motion on the mobile robot and it is a serious problem for the production system. When carrying objects slip off the mobile robots, they may be broken and the accident interferes with accurate traveling motion of the mobile robot. Then, in this study we set the purpose of this research to guide the mobile robot as fast as possible while keeping the objects not slip. Effectiveness of the guidance control with accelerative restriction of the mobile robot is verified with travelling experiment with mobile robot.

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We will propose the online path planning algorithm to navigate an autonomous mobile robot from the 3D data obtained by a laser range finder, without avoiding obstacles in the unknown environment toward the goal from the starting point. The planning path can be expressed as a Bezier curve, considering the direction of the robot, and the position and the direction of the robot can be obtained by a dead reckoning method. Examining the proposed algorithm, it is proved to be very useful for navigation of a mobile robot, and furthermore, the 3-dimensinal map can be easily acquired by a vertical scanning of the laser range finder.

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This study handles a safely maneuvouring control system developed for human symbiotic robots with an omni-wheeled vehicle. In this paper, we propose a flexible control method for getting over a difference in level, according to conditions of limitation to maneuvour caused by the structure and motion performance of the vehicle by itself.

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This paper describes support-equipment of operating a personal computer for users who have an obstacle on the regions of upper limb. The user wore a head set device with an angle sensor on the top of head and a distance sensor in front of mouth. Angle sensor could measure the roll and pitch angles of head, and distance sensor could confirm whether mouth was opened or not. In mouse operations, cursor could be moved according to the direction and magnitude of the tilted head angle. Click operation mode were started by opening the mouth for two seconds, and then each functions were executed by tilting the head.

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This paper describes a new human-machine interface based on mouth open/close motions. User attached the developed controller with the skin surface to observe the moth open/close states. The controller equipped a tiny magnet sensor by which the slight relative displacement between the upper and lower skin point of mouth could be measured. For a higher recognition ratio, the controller had a flexible structure to absorb the slight displacement caused not by operation but by mastication to eat something. Moreover, the misrecognition with speaking could be avoided by comparing the current mouth state with the previous one. Next, suggested method was applied for operation of the meal support equipment.

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In this paper, a new method of controlling a multi DOF robot was suggested. Humanoid robot equipped seventeen DOF was used as a multi DOF robot. Controller has a two DOF joystick, and accelerometer was put on inside. Joystick operations and tilting the controller were combined to increase the number of operation to assign the multi motion of the robot. In cases where the controller was set to the horizontal state, joystick operation could provide the walking motions. When the controller was set to the vertical state, direction of CCD camera equipped on the head part of robot could be controlled.

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In recent years, the computer spreads, and its users also go on increasing. However, everyone cannot handle it easily. The computer must be user-friendly and become what can be used intuitively. Then, the "gaze interface" which makes it possible to operate the computer only by watching the screen has been developed. Although the accuracy of gaze measurement has been improving recently, it is still unsuitable for use as a human-machine interface for the reason that the equipments are large-scale, and that the setting is very difficult. It will become practical if gaze tracking will start automatically by detecting the user in front of the display with one camera. We aim at development of a human-machine interface which makes automatic detection of the existence of people by detecting the movement of human blinking, and starts a calibration automatically, and measures gaze points in real-time.

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Task supporting system using head mounted display and augmented reality (AR) is described. Since measurements of deformation and temperature of a work piece is needed for line heating task, an interactive scheme that includes measurement instruments combined to the AR system is proposed. Whole system is designed so that the coordinates of the measurement instruments are transformed to the marker based one. It is performed by detecting markers using ARToolKit and a video camera attached to the instruments. Errors in position and pose of a marker detected by ARToolKit are experimentally investigated to estimate the practical merit of the design. Systematic errors caused by misread of a marker edge are analyzed. It is revealed that the position accuracy in the optical axis direction of the video camera is not accurate enough for the supporting system when single marker is only detected.

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A prototype of visual monitoring system is developed aiming to use for task support. The prototype consists of a video camera, a head mounted display (HMD), and a very small board computer as its major components. All of the components are mounted on a helmet. The optical axis of the video camera is aligned to have the same direction as that of the HMD. This makes the computing process in augmented reality easier and the task in a narrow space possible. An experiment is carried out to evaluate the performance of the prototype. The experimental result shows that support information is well transmitted to an operator through the prototype. Several problems to be solved are derived as well.

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We are planning to develop HFAMRO-2 which can play with people using the step-on interface. Therefore we would like to improve the mobility performance and to replace the range sensor from HFAMRO-1. This paper shows the modified design of mobile unit which will be able to double the speed of movement. And it also shows the comparison between new range sensor and old one based on the results of performance measurements. The new sensor can detect and measure the stepped foot more precisely.

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We propose new input method of operation. Instructions to robot are given by stepping on a part of operation screen that is projected on running surface by projector equipped on the robot. This paper examines the layout of instruction buttons on operation screen. And additional functions, the preliminary-announcement and indication of forthcoming movement and the discrimination of obstacles from stepped foot to apply autonomous movement and mouse cursor operation, are also discussed.

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For the operation of the remotely controlled robot, it is very important to provide enough view around the robot to the user clearly. Acquired images from multiple cameras are used to provide views around the robot. However, there are several weak points to the image of the camera. We need the system which can make up for those weak points. In this paper, we propose the method to correct image by sensor information, and to show it to the user by using GUI. Than this, the user can acquire information becoming necessary for work, and it comes to be caught information visually. In other words the user can recognize information more intuitively.

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An interactive tactile graphic display which acts by touch force has been developed as a trial. The trial model showed four usability problems through several usability experiments. Thus we re-designed three operation rules and developed a new image resampling algorithm to solve the problems. As the result, all problems shown in the previous system were solved. Furthermore a strategy of user interface design for interactive tactile graphic displays was shown through the development. In addition, an audio-tactile graphic system which can be used mainly to overcome tactile cognitive limitation was implemented as an application of the system.

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The exhibition to a high tip of a finger the space resolution becomes important in a tactile display in the conventional investigation. However, we must touch the tactile display that we can cover at a time at a tip of a finger in a bigger area practically very small. This paper proposes sense of touch exhibition to the palm for sense of touch stimulation of the big size area that cannot cover only at the area of a tip of finger and think about a finger-tip in the pin display and a difference of the shape communication of the palm.

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It is important that those who operate it understand the situation in surroundings of the robot to achieve a smooth operation when the robot is operated remotely. However, because robot and operation person's work spaces are different, the situation recognition is difficult. The improvement of the operativeness of the remote movement robot was attempted by aiming at the development of the operation support with software in this research, and using a human interface with a touch panel.

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This paper describes a video projection system with reduced motion blur using a high-speed DMD (Digital Micromirror Device) projector. Conventional DMD devices suffer from motion artifacts, which are observed as blurred moving objects, because of eye motion. A DMD projector displays grayscale brightness by pulse-width modulation and requires many patterns for a frame. In a motion video, image positions are updated per frame, which causes large motion blur. To address this issue, we propose a method in which image positions are updated per pattern. To examine whether the proposed method can give an improved result, an evaluation experiment was conducted. The result of the t-test applied to this evaluation experiment proved that there was significant difference at p<.001 between the proposed method and the conventional one, and the motion blur reduction was successful

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The development of accurate 3D hand model is a key to improve a model matching based hand pose estimation. This paper proposes a method to create an individualized 3D surface model of a human hand using voxel expression from images observed by multiple cameras. The link lengths of individual fingers of the user's hand are the most important features needed to create the individualized model. To create a hand model that corresponds the closest to the user hand, the lengths of the finger links are estimated by searching a set of models generated by the motion of the finger links. Using these models, the accuracy of the hand pose estimation was evaluated.

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In this study, we proposed a new passive force feedback system for an operator. A motion input device and a force feedback device are equipped independently in this system. The proposed method doesn't realize the real sense that the operator manipulates an object directly. But it is useful for the assist of a tele-operation system or force training system. A prototype force display device is developed and we discussed the method and the sensory property of passive force display for human.

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For the purpose of presenting 3D information for tele-operation, a method of displaying motion parallax by measuring only orientation of the operator's head is proposed. Assuming that the operator sits down in front of an object of task and gaze it, the position of its eye is estimated from the orientation of its head measured with an inexpensive sensor.

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