In this paper, the control method which locally applies the feedback linearization control into the rotary pendulum system is proposed. Since rotary pendulum has the 2-DOF underactuated-by-1 system, only the angular velocity scale layer is linearized. Experimental results show the utility of the proposed method in the real system.

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The wear characteristics of copper-impregnated carbon fiber reinforced carbon composites (C/C composites) was investigated using a block-on-ring type wear tester during application of a DC electrical current. Three types of C/C composite contact strip materials were tested. The wear test was carried out at a constant sliding speed of 55.6 m/s with a normal load of 59 N, and applied electrical currents ranging from 100 to 500 A. The arc-discharging rate, which is defined as the ratio of arc-discharging time to total sliding time, ranged from 0 to 35%. We also investigated the oxidation properties of the C/C composites with the TG-DTA. The results of the wear experiments indicate that the wear of copper-impregnated C/C composite contact strips was proportional to the arc discharge energy, which can be calculated from measurements of contact voltage and electrical current. The C/C composite contact strips with high strength carbon fiber were more likely to wear under high arc discharge energy conditions. The C/C composites made of higher strength carbon fiber were more likely to be pyrolyzed or degraded by oxidation than the C/C composite with lower strength carbon fiber. This difference is thought to contribute to the difference in the wear characteristics.

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In a former study, the authors developed a numerical simulation program in order to predict wheel-wear profiles, especially for wheel flange-wear, of railway vehicles where the rolling contact between wheel and rail causes wheel wear. In this study, a number of wheel profiles of vehicles running on a commercial line have been investigated. The investigation shows that wheel profiles of the same running distance do not always have the same worn profiles, so it is difficult to find the wear-amount tendency toward running distance. Therefore, the authors executed running tests on a test track, which are able to restrict various conditions, such as track curvature, running velocity and lubrication. The results of the tests show that the simulation program is reasonable and applicable to prediction of wheel flange wear.

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This paper describes the drivers steering behavior affected by the vehicle side slip angle during changing lanes. In order to investigate the influence of the sideslip angle to driver's steering behavior, driving simulator is employed to realize various vehicles with different side slip characteristics. We prepared three specifications, i.e. yaw rate and side-slip angle generate in the same direction, the opposite direction, and side-slip angle is kept to zero. In this study, we used two type second order prediction model. The one is the second order prediction by yaw rate and side-slip angle. Another one is the second order prediction by only yaw rate. And we discussed the effect of side-slip angle on the driver's forward prediction with compared the two prediction models.

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Recently, many researches about vehicle dynamics analysis under unusual condition like derailment and impact to an obstacle are increasing. In these conditions, longitudinal force applied to a car frame may exceed design load. In this paper, longitudinal strength of a railway vehicle at intermediate end in consideration of plastic deformation is evaluated. As a result, it is clarified that the existing vehicle structure has much larger longitudinal crippling strength than elastic strength defined in a standard. In addition, an effect of dynamics to longitudinal strength and a crippling area is evaluated.

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This paper describes analysis and corrective actions of passengers fall accidents from chair on line in chairlifts. Ropeway and chairlift accidents of the same kind show the highest frequency of occurrence in passengers fall accidents from chair on line. Analysis includes accidents occurrence situations of chairlifts without safety bar and with safety bar. Corrective actions to prevent passengers fall accidents from chair on line are discussed based on the above analysis results. Further corrective actions for safety are expected to be taken on the basis of lessons learned from these analysis and actions discussed.

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During moving and cargo-handling of a forklift, accidents may happen if the operator extends his head and/or his hands out of the cabin, and then have a collision with pallets and pillars. Optic devices are used as protect device installation. The examination is performed on controlling the system.

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There are ship images and non-ship images (noise) on radar images. Ship images on radar images are selected by officers based on officer's observation skill and experience. In order to save the effort of officer's watch with keeping the watch level, it is necessary to save the effort of the radar operation by officers. Therefore, purposes of this study are feature extraction on radar images and ship image detection based on feature points. This study is the first-step approach of automatic ship image detection on radar images. Many features of radar images were extracted by image processing and texture analysis using raster images of radar. As a result of cluster analysis using these features, it is possible to detect about 83% ship images on radar images.

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We have been focusing on wireless LAN for radiocommunication between ships for exchanging safety and efficiency navigational information each other. In the preceding trial, we used directional antennas and measured RSSI (Received Signal Strength Indication) and throughput between ships. However, the trial was held with one ship moored at the pier and just head-on situation. In this time, we carried out on-sea trial by sailing two ships keeping enough distance. By this trial, we confirm the characteristics of the directional antennas especially half-power angle which affected the radiocommunication performance. As a result, we achieved over 1 Mbps throughput between ships which was our target.

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It is possible that a train's crew cannot recognize a derailment immediately, even if a running railcar derails. From a serious accident in the past, we learned that damage from secondary collisions can occur when the derailed train continues to run. Therefore, in order to help mitigate and reduce these kinds of accidents, we have developed a derailment disaster algorithm. Also, in combination with the Train Protection Radio, we have made a "Train Protection System to Prevent Secondary Accident" device widely available in order to prevent secondary accidents by stopping other nearby trains. The derailment detection algorithm continuously monitors car body acceleration and determines if a derailment occurs by observing wave pattern abnormality. The development of this algorithm has been validated via inspection by desk simulation and examining derailment conditions during normal train running. The derailment detection device which was in use is comprised of an acceleration sensor and a microcomputer. Furthermore, triggered by a derailment accident which occurred in 2005, the "Train Protection System to Prevent Secondary Accident" device has been put into practical use to detect derailments, collisions and rollovers. In recent years, it is being used as standard equipment on 90% of JR East trains running in the Tokyo area, and its usage is still increasing. By the "Train Protection System to Prevent Secondary Accident" device, a rail vehicle derailment at Sagamiko Station of the Chuo Line was detected by this algorithm in 2013. This device functioning together with the Train Protection Radio automatically detected the derailment of the said train during neighborhood running and safely stopped the train. This clearly demonstrated the effectiveness of the concept of this technology.

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Passengers have a risk of gettig injured in collision with interior components in the event of train crash accidents. In order to lower the risk of passengers getting seriously injured, it is important to figure out the situation of collision between passengers and interior components. In this investigation we intended to figure out the behavior of interior components when passengers collide with them. We got mechanical strength properties of interior materials by performing tensile tests. Besides we examined the behavior of boards made of each interior material by striking them with an impactor and carried out the reproduction analysis.

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Approximately a third of the traffic accident fatalities in Japan are caused as a result of accidents while a person is in a vehicle. Collision from the frontal direction accounts for 53 percent, a much higher percentage than accidents involving collisions from other directions. In Japan, laws concerning collision from the front direction are defined in the Safety Regulations: Full frontal rigid barrier impact test and Frontal offset deformable barrier impact test. We focused on these two tests and studied over 50 cases to research the degree of injury value during tests at the time of certification. In Full frontal rigid barrier impact test, we observed little difference between the average injury values for the driver and passenger. In Frontal offset deformable barrier impact test, the values were higher for the driver than the passenger when comparing the average injury values of the head and chest. In Full frontal rigid barrier impact test and Frontal offset deformable barrier impact test, the average chest injury value was higher compared with the average head injury value. For head injury criterion, the average value for Full frontal rigid barrier impact test was higher compared with the average value in Frontal offset deformable barrier impact test. For both the Full frontal rigid barrier impact test and the Frontal offset deformable barrier impact test, we observed that the heavier the test vehicle weight, the higher the decrease in the injury value.

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[in Japanese]

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Resent year, the pedestrian fatality accounts for the great majority. Therefore, it is important to prevent pedestrians from being involved in fatal accidents. In the previous study, the authors proposed the safety speed index at overtaking a pedestrian in narrow roads. This study focuses on drivers' behaviors in the target scene in the Near-miss Incident Database. By comparing driving data in the Near-miss Incident Database and the proposed safety speed index, the validity of the proposed safety speed index is shown.

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Recently, many safety systems for automobiles have been proposed. However such systems seem only to focus on individual users. In contrast, our research focuses on a "Mutual Assistance" system. In this paper, we investigate and evaluate a warning system based on mutual assistance to avoid right turn and oncoming vehicle collisions (left turn and oncoming vehicle collisions in left hand drive regions). The warning system is designed to warn third party vehicles of potential risks. We evaluate the warning system using a driving simulator. The results were analysed with respect to collision rate, collision speed, TTC (Time-To-Collision) and Behavior-Specific Rate of Occurrence. The results indicate that the warning system statistically decreases the risks of right turn and oncoming vehicle collisions. Also, we discussed appropriate timings for early warning alerts.

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To prevent accidents with road crossing pedestrians, we analyzed the road crossing behavior of pedestrians using the near-miss videos and data. Thus we extract that the pedestrians are not aware of the approaching vehicles as a factor of dangerous crossing. To evaluate the possibility of collision, we modeled the crossing scene and organized the conditions that the collision could not be avoided by braking of the vehicle when the pedestrian unaware of approaching vehicles crossing. In such a condition that it is difficult for the vehicle to avoid the collision, we proposed informing the approach of the vehicle to pedestrians as one measure of collision avoidance.

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Pedestrian accident account for approximately 30% of fatal accident of traffic accident. Therefore, it is important to develop countermeasures of active safety or passive safety, for improving pedestrian safety, by clarifying reality of situation of damage. In this paper, author tried to clarify the relationship between collision velocity and injury level of[pedestrian by damaged region as statistical data by processing traffic accident data stored ITARDA(Institute for Traffic Accident Research and Data Analysis). In collision velocity less than 30km/h, frequency of slight injury by bruise, laceration or abrasion of legs is high. And in collision velocity over 50km/h, frequency of fatal or serious injury by fracture of head is high.

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Head-on collision accident is the most frequent accident, therefore, it is important to develop the active safety technology to prevent them. The experiment was conducted on the test course with experiment vehicle to collect driving data and a simulation when passing through a non signalized intersection was established to clarify elderly drivers' behavior. This paper describes their risk factors based on simulation results.

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This paper investigated the effect of driving assistant system which is designed for anticipating pre-preceding vehicle on traffic flow stability. The authors have proposed a driving assistant system which is referred to as PRE3 (prediction by pre-preceding vehicle) and confirmed through a driving simulator (DS) experiment that it is efficient for the following driver to anticipate the pre-preceding vehicle in order to make the platoon stable. In this paper, it is investigated whether the effect of PRE3 is extended to the macroscopic stability of traffic flow. Driver's behavior is modeled based on an Optimal Velocity (OV) model and validated using a DS experiment data. Numerical analysis through a traffic simulator confirmed that PRE3 is also efficient to make the traffic flow stable without any deterioration of velocity along a freeway corridor.

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Drowsiness causes fatal and heavily injured traffic accidents. Therefore, the development of the method to prevent drivers' drowsiness is demanded. The supply of fragrance is one of the useful methods to awaken human, therefore, in this study (l)-menthol which has a stimulate effect was chosen and its effect was tested. The electrocardiogram which is one of the most convenient measurement methods was employed to detect subjects' drowsiness, then the variations of R-R Interval and autonomic nervous system were analyzed.

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Drowsiness causes fatal and heavily injured traffic accidents, therefore a number of studies on the detection of drowsiness or on the inhibition of it have conducted. In present study, electrocardiographic measurement which is one of the most convenient measurement methods for subjects and experimenters was chosen to detect of driver's low arousal state. The variations of R-R Interval and autonomic nervous system indexes during driving simulator were verified by employing frequency analysis and Lorenz plot analysis.

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This study evaluates driver's workload and pleasant or unpleasant emotion by measuring brain activity. Driver's brain activity is measured using near-infrared spectroscopy (NIRS). Whether the reduction of driving workload by Adaptive Cruise Control (ACC) system can be evaluated from brain activity was discussed through experiments using a driving simulator. The relation between the brain activity and the pleasant or unpleasant emotion was evaluated using International Affective Picture System (IAPS). These results suggest the possibility of evaluating driver's workload and pleasant or unpleasant emotion from measurement of brain activity using NIRS.

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Visual information would influence the perceptual sensitivity for vibrations of vehicle motions as well as bodily information. This would be known generally but the detailed mechanism has not been sure yet. We are trying revealing the mechanism and the contribution ratio of visual/bodily information by using the driving simulator. In this paper, we would show some results of the experiments, especially and pitch direction.

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Based on the analysis of elderly driver's actual driving behavior, we classified unsafe driving behavior into 4 categories by focusing the consciousness and the intent. By extracting the causes of unsafe driving behavior, we develop quantitative index to discriminate the consciousness and the intent at an intersection where vehicles must stop temporarily on entering. Results of the experiments show the clarified that the maximum velocity and uneven reaction speed are selected as the quantitative index. Moreover, it is verified that 76.6% of the driving behavior about the consciousness and the intent were discriminated by the index.

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The objective of this study was to investigate on the stabilization ofan inverted pendulum type vehicle by attitude control. In this paper, an attitude control by gyro moment was proposed with the modeling and simulation studies of an inverted pendulum type two-wheel vehicle equipped with single gimbal flywheels. The simulation results had shown that it is possible to stabilize the vehicle with attitude control by gyro moment from the flywheels.

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In this work, we propose a new personal mobility vehicle (PMV) with the purpose of recreation. Our objective is to develop a new small sized vehicle to provide leisure experience to the users by traveling with the vehicle. A prototype is developed with collaborative steering and handling systems for creative maneuverability experience.

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Suborbital spacecraft which can reach an altitude of 100km has been studied in JAXA. Suborbital spacecraft is a vehicle proposed for the research and experience under microgravity condition. Suborbital spacecraft has been studied with a baseline shape. In this study, aerodynamic characteristics of the baseline shape was evaluated using numerical simulation. As a result, the shape of the baseline head part generated a strong shock wave. A modified shape with area rule is applied to the head part. Lift and drag were improved with the modified shape.

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Various micro-electric vehicles (EV) have been made by a lot of manufacturers in the world since approximately two decades before. Few numbers of such small cars, however, have come into use in Japan. This is mainly because the proper utilities have not been considered sufficiently while the micro-EV's would not be substitutes for the ordinary cars including "Kei (Light)" class cars in Japan. The micro-EV's can be very useful transfer method when their characteristics or their essentials are considered enough. Several kinds of prototypes of micro-EV's made by the authors are shown in this paper and the prototypes have various utilities as maintenance service in the woods in the suburban areas, picking-up a member of a family to hospital and mothers' transfer with children more than one, etc. The benefit of such prototypes is verified at the same time that the functions of them are not provided for the ordinary cars.

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This paper describes a proposal of new steering system which can provide easy operation of vehicle to all drivers. We elucidate the factor of the problem of conventional steering system in low speed range. We compared the steering operation between the beginner driver and the skillful driver. The beginner driver held various positions when he operated steering. In addition, the operation sometimes meandered after the returning straight. We thought the factor of the problem is changing the hand holding the steering wheel. However, these problems do not occurred for the skillful driver. In other words, it is thought that changing the hand holding the steering wheel is the operation that a human being learned by experience. Therefore, we propose maneuverable steering system without changing the hand holding steering.

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This paper studies a method for introducing the given course geometry into the trajectory generation of the vehicle maneuver. An idea of the method is to align objects around the outer border of the course. These obstacles are defined by means of a p-norm formulation. Numerical results of the optimal control problem show that the optimal trajectory can be obtained by the proposed method.

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These days, mission with Unmanned Airial Vehicle has been popular, but it is difficult to get precise position information essential for the mission when it is impossible to use GPS because it is performed indoors and so on. In this paper, we consider a localization algorithm that can be processed on-board. In this method, UAVs measure relative positions mutually, and this information is used in particle filter. Then we examine the performance of this method. It is proved that for short time it is possible to trace the true position by using this algorithm but the estimated value diverge if you use the method for long time. Finally, we consider an alternative scheme that aims at integrating particle filter output into INS output.

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This paper proposes a brush-cutting robot which operates a brush-cutter selling on the market and cuts the grass automatically. The robot vehicle is constructed with a center articulated body, a manipulating mechanism of the brush-cutter, sensors and the controller. In order to get the own position continuously, two LRFs (Laser Range Finder) and a GPS campus are installed. Authors proposed SSM (sensor steering mechanism) method which is a lateral guidance mechanism that an articulated vehicle using center bending mechanism achieves stable high speed running. The developed robot is able to guide laterally for mowing without left over by SSM method and self-localization method using 2D-map of 10cm grid and LRF. This experiment uses this robot to show the result of running and mowing. As a result, the proposed system can realize mowing without left over by setting the overlap to 20cm.

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This paper presents a detection method of road marking using Laser Range Finder (LRF) intensity of surface for getting the road traffic information. Many studies of road signs and road marking detection method have been mainly using an optical camera. However, sometimes an optical camera cannot get effective image because it is affected by ambient light. On the other hand, intensity of LRF is hardly affected by those conditions. For this reason, road surface texture images are made by LRF refractive intensity of surface. The type of road marking was identified by a simple template matching from this image. As a result of the paper was that the present method detected road marking of "止まれ" with high accuracy when the velocity of the vehicle was 30 km/h or less. The detection rate of the speed limit signs on public roads was about 92% and the pedestrian crossing warning sign was about 87%.

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We propose a trajectory control design for a wheeled inverted pendulum robot, which can be considered as a mechanical system with nonholonomic constraints. First, we make a mathematical model of a wheeled inverted pendulum robot as an implicit Lagrangian system and then show the passivity based control by introducing a controlled Lagrangian in the context of the implicit port-controlled Lagrangian system. Lastly, we demonstrate our theory by some experiments and numerical simulations.

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The demand of two-wheeled inverted pendulum vehicles in the market is increasing because it is much more compact than cars and motorcycles and suitable for movement in a short distance. In this research, the control algorithm which enables the driver to operate the vehicle more freely was studied to expand the utility of the vehicle. In the study the difference between the control gain which was taken through the mechanical model analysis and the one which was adjusted by the human drivers. It was consequently cleared that the human operators also control the system using weight movement. Accordingly, the control gain considering the weight movement almost agreed with the one which was adjusted by the human operators.

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I'm developing the new mobility of skateboard type which can be carried into a public transportation. And the experimental model exists in my laboratory now. This experimental model can run at about 13 km/h. The time this experimental model can run continuously is 30 minutes. And the possible weight which rides is 80 kg. The weight of an experimental model is 14 kg. Fundamental travelling performance is as mentioned above. However, This experimental model has a some problem. Especially a big problem is being unable to over a higher step. Hence, My study is enabling it to over a higher step with an experimental model.

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Relatively, new marine container terminals often have a rectangular shape by making use of reclaimed land. However, due to geographical reasons some terminals have an irregular shape. At the terminal with irregular shape with RTG operated, the storage capacity depends on the location and number of aisles which yard trailers move. In this paper, we consider the aisle location problem at the container terminal with polygon shape. We also consider the container storage problem under the aisle location obtained, in order to minimize the total service time and to minimize the yard space utilization.

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This paper describes simulation study on flight-deck interval management (FIM) operation at Tokyo International Airport. FIM is an airborne-based interval management operation that is expected to achieve accurate time spacing and reduce fuel consumption. CDO is applicable to low-density traffic area at present and it is needed to confirm the safety of FIM operation by simulation in order to apply CDO to congested airport. In this paper, models for the simulation were created using Stochastically and Dynamically Colored Petri Net (SDCPN), which allow us to describe complex systems. Based on this model, several simulations were conducted to evaluate the performance and effectiveness of FIM operation.

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This study deals with a development and evaluation of a motorcycle simulator to analyze rider's control algorithm. This paper described about the evaluation for a visual system configuration as underlying data of such simulator construction. We had subjective test using a flat screen to evaluate for a visual scene of the simulator. And, it is concluded that wide-field screen vertical view angle and stereoscopic video projector are effective. In addition, using these results, a new spherical screen system using 3D projectors is constructed. The motorcycle simulator will be improved using this system.

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As an effort to support the earthquake disaster reconstruction of the northeast (Tohoku) region, the "Next-generation Energies for Tohoku Recovery (NET) Project" was initiated in 2012. Under this project, Advanced Mobility Research Center (ITS Center), Institute of Industrial Science (IIS), The University of Tokyo and New Industry Creation Hatchery Center (NICHe), Tohoku University has collaborated to promote the research and development of a mobility integrated energy management system (EMS) that supports the sustainable development of a disaster resilience region. This study involves the survey studies of the mobility capability of disaster area residents (including the elderly) during normal and emergency conditions, and the formulation of basic human behavior models. In addition, a driving simulator is developed to reproduce and analyze the energy-mobility movement. In normal condition, the analysis of human factors is conducted with the energy management system. In emergency condition, the studies of information providing methods and evacuation methods are carried out.

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Haptic guidance steering, which produces torque in steering wheel to guide the driver to steer along the desired trajectory, is the assistance system which has been proposed as a continuous assistance system. The authors propose to use it for vehicle navigation. Compared with the phonetics, the driver can feel the direction without dispersing the attention. The experiments to change the lane with haptic guidance steering are carried out compared with phonetic assistance. The results show the effectiveness of the haptic navigation.

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Smart phone is widely spread, and the use of navigation system by smart phone is developing. This can provide more kinds of information rather than common type of car navigation system. On the other hand, using smart phone navigation system may cause disturbance and distraction for drivers, which might generate a traffic accident. Therefore the safety of the navigation system by smart phone is needed to be evaluated. The study assesses the safety through the experiment by a driving simulator in which a car navigation system can be utilized. The safety is estimated by subjective assessment.

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In the project of Energy-saving ITS Technology, reliable automatic platooning by trucks is a main objective for highway transportation. Utilization of the driving simulator is useful to examine the safety of the automatic platooning by the Project. To examine safety of the proposed system, an actual cabin of a truck is mounted on a driving simulator, and the automatic platooning control is achieved. The behaviors of drivers when the system failed in forming platooning with manual or adaptive cruise control driving are analyzed to examine the reliability of the system. For the reaction delay of the driver, truck could not stop safely in the driver brake. However, if there is brake assist, it enable stopping safely.

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In the fields of improving the highway traffic safety and developing driving assistant system, it is important to understand the relation between the driving operations and the cortical brain activity corresponding to road geometry. In this paper, we performed a series of experiments using a driving simulator on a special designed course including several left and right curves. Meanwhile, the cortical brain activity was also measured by a functional near-infrared spectroscopy (fNIRS). We analyzed the characteristic differences of driving operations about left/right curves. Furthermore, accordantly difference of activation of brain regions between left/right curves was also extracted independently. Results show that fNIRS can be used in driving simulator experiments to evaluate drivers' brain activity for curve driving.

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