Force and torque induced by traveling motion and moving operations of a mobile manipulator effect dynamically to the objects being carried on it. If the induced inertia force be bigger than the static friction force, the carrying objects start to slip on the mobile manipulator, and further the start of slipping of one object may cause dangerous collapse of all carrying objects, since the start of slipping makes the traveling acceleration increase in a stepping manner through stepping reduction of coulomb friction force between carrying objects and vehicle. And moreover it interferes with accurate traveling operations for dexterous behaviors of mobile manipulator. A purpose of this research is to propose a model of mobile manipulator to analyze the influences of the slipping to the motion and to discuss conditions for the controller of guidance and moving operations to avoid slipping. In this paper, We propose a model of mobile manipulator with n links including the slipping motion of the plural carrying objects. Using the proposed model, the influences of the slipping are analyzed and justification of the model is verified by simulations.

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A crane mounted on a tower-like flexible structure called the 'Tower crane' has a problem that a fast transfer of the load causes the sway of the load and the vibration of the flexible structure. Furthermore if the length of the load rope varies, It is difficult to control by the fixed compensator, because the natural frequency of the load rope and gain of the plant to control input vary also. We have already verified the efficiency of the gain-scheduled H_∞ compensator by simulations and experiments only in the up-and-down direction. However, the rotational direction have not be implemented the gain-scheduled control. So, this paper designs the gain-scheduled compensator for both directions and verifies its efficiency by experiments.

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In this research, the operation analysis for transfer crane system of a seaport container terminal is investigated. In the present paper, the effects for stowage row of a transfer crane are analyzed by simulation model. As a result of simulation analysis, the proportion in traveling time affects the efficiency of the operation time and it became clear to be better the operation efficiency of the 8 rows style than the conventional 6 rows style.

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The Hanshin-Awaji Earthquake of 1995 caused extensive damage to the container handling cranes at the container terminals of Kobe Port. Consequently, the authors developed a seismic isolated container handling crane that could avoid damage and wheel derailment for practical use. These practical cranes were installed at Tokyo Port Terminal Japan in October 2001. The authors used laminated-rubber isolators as system to make the natural period of the crane longer and isolate earthquake energy. Laminated-rubber isolators have been widely installed on bridges, buildings and other structures for many years. This paper verifies the seismic isolation system effectiveness by a scale model test, such as the reduction of crane acceleration response and prevention of wheel derailment, and shows the results of the simulation by nonlinear seismic response analysis.

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In this paper, we make simulation model by finite element method and high(10) mode analysis. The tracking control problem and the anti-sway control problem for the rubber tired transfer crane are considered. Since the tired transfer crane swerves from the demand course, it needs the tracking control to keep the demanded course. At the same time, the anti-sway control is needed to control the vibration of building. Generally, since the model of the transfer crane can be expressed as one of nonholonomic system, it is difficult to design a controller. This paper propose a design method of a controller to keep the demanded course and control the vibration.

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Building of the road surface conditions decision system for on the car was done by this paper. Past albedo meter couldn't cope with measuring at night because solar light was used.Therefore, this paper proposes an on-board road surface sensing system using a pair of solar cells and an additional light. From the experimental results, it is shown that the sensing system can measure the difference of road conditions, not only at daytime but also at night. Moreover, image treatment was used for the conditions of the decision which were difficult, and it coped with it only by the albedo value. The reliability of the decision rose as a result.

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By the development of vehicle dynamics and vehicle dynamics control, the vehicle is more safely. Almost the vehicle dynamics model is tested by lane-change. The lane-change is simulated on the straight road. In this paper, the vehicle dynamics model is simulated by the lane-change on the curve road. And compared the result on straight road with the result on curve road. The vehicle dynamice model is simple two wheels model with the roll model. The driver model is simple preview tracking control model.

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We have developed and verified a new suspension system for an electric vehicle naming Tandem Wheel Suspension System (TWS). TWS is a new suspension concept for passenger class electric vehicle that makes a great progress in space utility, handling ability and ride comfort. A general concept of TWS is replacing the 4 larger sized wheels with 8 smaller wheels. The 8wheels consist of the four couples of adjoined two wheels. These two wheels are connected with the hydraulic piping installed in each shock absorber. Further more, those hydraulic piping are connected with the unit of large capacity hydro-pneumatic spring shock absorber. The hydro-pneumatic spring shock absorber unit serves as inputs and loads from adjoined two wheels. We have made simulation analyses on ride comfort and developed the running prototype to verify TWS performance. This running prototype has eminent potential in driving ability. These simulations reveal that ride comfort of TWS should be improved compared with 4wheels reducing the body vibrations by 5 times under 1 Hz.

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We have developed the Battery Built-in Frame (BBF) for an electric vehicle. This structure provide the space for battery storage in aluminum extrusion molding under the floor, which was adopted in "Luciole". In this paper BBF was extended to store all the electric components needed to drive an EV, such as batteries, inverters, a vehicle controller, a DC to DC converter and power switchers. We named this concept "the Component Built-in Frame(CBF)". This modification resulted in not only the expansion of cabin space but also the improvement of the body stiffness by maximum 39%, generally 7% in torsional rigidity, and maximum 24%, generally 21% in flexural rigidity.

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This paper investigates the feasibility of applying the stochastic robustness method to the evaluation of the robust vehicle control systems. Vehicle motion is modeled by nonlinear dynamics equation containing 10 uncertain parameters. The system robustness is characterized by the probability of instability and probabilities of violation of prescribed performance indexes, subject to the variation of uncertain vehicle parameters. These probabilities are estimated by applying the Monte Carlo method to the results of a large number of simulated vehicle motion. Three nonlinear vehicle control strategies are chosen to demonstrate the use of stochastic method to analyze and compare the robustness of control designs.

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In our previous researches, we estimated the reduced quantity of aerodynamic drag of trains by smoothing under-floor construction. However, we did not compare the results of wind tunnel tests with those of on-track tests, or verified the accuracy of wind tunnel tests for the aerodynamic drag of trains. In this research, we estimated the aerodynamic drag of a train-set by wind tunnel tests. Regarding the reduced quantity of the aerodynamic drag of trains, we compared the results of wind tunnel tests with those of on-track tests. These test results show that the reduced quantity of the aerodynamic drag of trains by wind tunnel tests approximately agrees with that by on-track tests.

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In this paper, the relation between the longitudinal acceleration and the changes in attitude were studied, to define the criteria of riding quality of standing passengers on railway vehicle. Longitudinal acceleration, pressure distribution under foot and move distance of body were measured in the field running tests. Some information was obtained about the limit values of longitudinal acceleration keeping both hoot position.

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In this paper, dynamic simulation study of the running performance of the AGT vehicle with the single-axle bogies are described to show the characteristics of the single-axle bogie in realistic situation. The multi-body dynamics modeler, DADS, is used to build the dynamic model of AGT vehicle with single-axle bogies and this is used to demonstrate the vehicle motion in actual guideway. The target AGT vehicle consists of front bogie, rear bogie and body. The each bogie consists of bogie frame, rotating frame, guide wheels and running wheel. Twenty seven (27) rigid bodies including sprung mass are used for the vehicle modelling. Suitable joints that connect each rigid body are selected and applied to realize the actual movement. The multibody dynamics code is used to built the dynamic model of AGT vehicle with single-axle bogies and this is used to demonstrate the vehicle motion in actual guideway. It is demonstrated that the vehicle dynamic response can be obtained in realistic situation by using multibody dynamics code, that is useful for designing both vehicle and guideway.

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Magnetically levitated vehicle, so-called Maglev vehicle, is noticed as the next generation high-speed public transportation system. For the practical use, it is important to improve the ride comfort at high-speed operation. Maglev vehicle is composed of lightweight car bodies and bogies mounted on super-conducting magnets (abbreviated as SCMs) and on-board refrigerating systems. It is rather difficult to design the secondary suspension as a vibration isolation system between the car body and bogie, because the ratio of sprung to un-sprung mass is small and the damping between SCMS and ground coils is very small. To improve the vibration control performance, active or semi-active suspension systems have been applied to this system. Moreover a new technique for obtaining magnetic damping is investigated using distributed power collection system. This paper The characteristic of the Maglev vehicle system was examined by the difference of the input turbulence in this research. Moreover, the effect of the electromagnetic damping on the control of the secondary suspensions was examined.

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This paper presents the outline of the developed experimental setup for guideway vehicles with scaled model. It is important to study on the interaction between wheel and rail to improve the running performance of vehicles. The scaled model experiments are very useful from the viewpoint of cost and availability. The test machine with roller rig has several drawbacks in simulation of tight curved truck. In the developed experimental setup, it has a tight curved truck(R=3.3m) with variable cant. This allows us to observe the wheelset behavior under the various curved truck conditions. This paper shows the detailed feature of the set up and application plans for experimental study on some new projects.

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Recently, commercialization is advanced to the warning system for the lane deviating prevention because of the progress of the sensor technology of the image processing technology etc. However, it is difficult to forecast departing several seconds after and the time to spare for the risk hedge is short. Therefore, the strategy by which reactive time of the driver is shortened is requested. This time, the torque was given to the steering wheel aiming to shorten reactive time of the driver to warning and the lane departure warning system which used bodily sensation (tactile) was developed. And, the effect was confirmed by a basic experiment with a driving simulator and the real car running experiment.

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We proposed the designing methodology to optimize the warning timing of Lane Departure Warning System and Forward Vehicle Collision Warning System. This warning timing can keep the time margin to avoid the lane departure or collision, and also minimize the fiequency of warning outputs. As regards the time margin, we observed that 90%ile of maximum lateral deviation is less than 0.3m when the warning timing was set at Time to Lane Departure = 1.0s, and also clarified that all of the driver can avoid the collision to the preceding vehicle when the warning timing was set at Assumed Delay Time = 1.0s in the Stopping Distance Algorithm. As regards the warning frequency, we observed that the frequency of lane departure warning is less than 0.5% when the warning timing was set at Time to Lane Departure =1.0s, and the frequency of forward vehicle collision warning is less than 0.5% when the warning timing was set at Assumed Delay Time = 1.0s. It can be concluded that Time to Lane Departure =1.0s and Assumed Delay Time = 1.0s are one of the appropriate timing for lane departure warning and forward vehicle collision warning in view of keeping the time margin and also minimizing the frequency of warning outputs.

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Recently, in-vehicle navigation devices have become very popular. Therefore accidents influenced by in-vehicle navigation devices are increasing. We analyze accidents using statistical method accessing a national accident database to discuss safety usability of in-vehicle navigation devices. Accidents influenced by in-vehicle navigation devices are characterized by vehicle type, accident type, driver biography, time of accident, a day of week, area of accident location, road geometry, driver behaviors, vehicle velocity, etc. Tendency of drivers using devices may characterize accident tendency. Moreover visual distraction by in-vehicle navigation devices may influence accident occurence.

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Recently, by the practical use of ITS, it is promoted that a driver is provided a lot of quantity and various kind of information from the surroundings and vehicle all the more. Particularly, the diffusion rate of the multifunctional car navigation system has being a marked increase. As such, it is important to examine the effective presentation method by the car navigation system in the driving situations. This paper describes the examination based on experimental results that the difference of the driver's behavior between the route guidance by the passenger's voice and the route guidancc by the computer synthetic sound. In addition, it is examined that the frequency of the driver's gaze to discrete observation subjects at city road.

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Since guidance is insufficient, parking lots become empty and the parking spaces are not used effectively. To correct this, we developed and applied a system able to retrieve parking lot information easily using a portable telephone connected to the Internet. To provide the benefit and convenience to parking lot users, improve parking lot capacity usage, and help ease traffic congestion, parking lot users are provided information on parking status(full vs empty), etc.

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In order to get high reliability of a product, at the design stage the designer has to consider the different kinds of environmental loads acting on a product. If a product design proceeds without considering enough reliability, it will lead to the reduction of design possibility, efficiency, and also the effect of problem elimination. In this paper, authors propose the framework of failure information management system to carry out reliability design that can stepwise support a design from the conceptual design stage to the detailed design stage. In this system, the failure cases are represented as the information network model. And also this system can show a designer the failure information with the required reliability analysis that are FMEA and FTA.

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The transportation of the object by the legged robot of the plural or units has been being researched so far. It will be thought that the path plan to base the environment which hits doing of the legged robot such as differences and slopes and obstacles the transportation work becomes important in the future. Then, this research assumes a complex environment when the ship comes alongside the pier to be a shake model of the grounding plane agitation, constructs the environment first on the simulator, and proposes a suitable posture control for four loading transportation of the robot.

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In our research, we are aiming to construct a system which put back washed clothes in order as a house keeping robot. In this report, shape and posture estimation method for washed clothes are proposed based on the movement of the feature points of laundries during the robot's operation.

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In recent years, concrete safety measures are possible by maintenance of the international standard related safely. However, such safe technical know-how also has few systems which educate by necessarily not being fixed. Then, in this research, the designer of a machine, a manufacturer, and a user propose the system which can learn suitable safety measures. This system consists of "a man-machine system cooperation work system" and "an imitation line of a large-scale production system."

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This paper proposes the new hold monitoring system of industrial robot considering economical efficency and safety. The movement of large number of driving shaft of robot is monitored by sinple magnetic reed switches. The robot is controlled by fail-safe triple diversity controller with self-checking by safety information, that is generated by ON-OFF type reed switches. The tamper proof countermeasure can be possible by this equipment.

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A concept of lightweight EV has been developed in orderto maintain mobility of senior people in our aging society and to protect our environment. Together with this vehicle, a concept of low speed traffic systen in neighborhood is proposed.

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In this paper, we propose a new position sensor-less control system for an electric vehicle that is driven with a permanent magnet synchronous motor. To drive a permanent magnet synchronous motor high efficiency, we need to do the vector control. The rotor position of the motor is necessary to do the vector control. A proposed method detects the rotor position of the motor by motor currents, and can materialize the low cost motor control unit. The position sensor-less control system is suited to an electric vehicle, because it has high responsiveness. As experimental results, the system was possible that it corresponds to the unique action of the vehicie.

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Series hybrid electric systems are thought to be suitable power systems for motor vehicles in urban traffic. It is important for this system to improve the comprehensive energy efficiency when components are combined, and to evaluate it appropriately. In this report, the technique to grasp energy loss in detail that occurs when electric power flows complicatedly in the series hybrid power system has been examined. And, the energy efficiency of the series hybrid power system on urban driving has also been evaluated for a trial.

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The Toyota Intelligent Multimode Transit System(IMTS) is realized through combining the ITS technology for fullyautomated cars with existing rail-way technology as an innovative transit system. At the Awaji Farm Park we have developed the IMTS specifically designed for the transport of visitors between two major areas. This is the first introduction of the IMTS as a practical transport. The system is composed of fully automated buses and a road-side system as a whole. The primary functions of the buses are automated steering control and pratooning. Over the dedicated lane for the IMTS blocking sections are fitted and an automatic train operating is installed. Here, the system configuration, bus control and operating system are shown.

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We propose an allocation planning method for the transfer crane (RTG: Rubber Tired Gantry crane) in a container terminal. The proposed method has two characteristics. The first is to consider the interference among the RTG such as deadlock and blocking. The second is to reschedule the assignment and the routing to the RTG already planned if it is possible to minimize the total traveling time of all the RTG. The second one is for the case where RTG waiting for work obstruct RTG at work or traveling. We take the example to show that the proposed method is incorporated into a yard operation and the system is constructed. We consider that the proposed method is easy to apply to the automated container terminal that is expected to introduce unattended RTG in the future because the proposed method is possible to output the traveling route of each RTG.

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The globalization of world economy by which locations of productions and consumptions has been diversified into nations has resulted in rapid growth of demands for the intermodal container transportation. This demands cause heavy traffic jam of trucks at the gate of container terminals. This paper tries to investigate economical loss and environmental damages caused by the traffic congestion. To explore better solutions for reducing the congestion, the Monte Carlo random simulation model is applied for queues of trucks observed at a gate of container terminal in a Japanese port. This simulation model simulates two possible alternatives of increasing in number of slots of gate and decreasing service time of checking in gate by which the traffic congestion can be reduced. This paper examines innovative technologies of gate systems that can be used for the alternatives and finally suggests that which one is more ecological to the Japanese container terminals.

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Environment Protection and Customer Satisfaction concept is most interesting subject now a day. At the same time, information and communication technology is developing rapidly and they say that it is IT (Information Technology) revolution era now. Under these circumstances, transportation of cargo by motor vehicle takes major part in environment protection subject in the field of logistics business. We developed and report on planning system for motor vehicle transportation by using IT technology, whict realizes real time tracing and EAT (estimated arrival time) information service with suitable environment protection purpose.

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As the universal communities are growing, demands for small-sized elevators which needs small hoistway area are increasing. An elevator system to reduce the hoistway area is proposed in this paper. This elevator system has three characteristics. The first is self-propelled system. A winding drum drive which has motor and reducion gears built-in is attached on the bottom of a car. And the car winds up itself. The second is no couterweight and no machine room. So hoistway crossectional area is reduced to less than 80% of the former elevator with couterweight. The third is easy installation. This system has simple roping and layout. And the car with winding drum drive is pre-assembled and tested at a factory. That leads to a reduction in costs and a shortening of manufacturing term. In this paper, a construction of winding drum drive, a layout of elevator system and the results of an experimental elevator are shown.

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The Electro-Magnetic-Suspension (EMS) system with a circle-cross-section rail succeeded the banking of a vehicle while running in curve. In the system, the damping in tilting motion is so small that any disturbance will make the vehicle oscillation without friction. So vibration control system made by the rotor with active control was proposed. The feedback control of the rotation of the rotor by sensing tilting angle with gyro sensor realizes equivalency skyhook damper for tilting motion of the vehicle. In this paper, simulation and experiment are carried out, and varying the position of the rotor in this vibration control system is investigated.

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Experimental result from a series of vibration measurement test of real railway vehicle is presented in this report. In the measurement test, both stationary vibration test using electrodynamic exciter and running test were carried out to investigate the vibration characteristics of the carbody as three dimensional structure. The effects of support condition of the carbody and running velocity upon the vibration response are discussed, and the modal characteristics are described, too. It is found that the eigenfrequencies concerning to the vibration of floor increase according to the supporting condition changes from block support to air spring support. It is also shown that the vibration of this carbody is complex and the roof and the floor looks to vibrate independently.

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Vibrational transmissibility of aluminum alloy double skin structures utilized for car bodies of high-speed railway vehicles are presented. The structure is treated as elastic beams and its transmissibility is calculated with Finite Element Method (FEM). The comparison of the simulation results with the experimental results shows that the proposed method to calculate the transmissibility is valid.

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Recent lightweight railway vehicles tend to express complex vibration motion such as roof and floor vibrate out of phase. Simple beam model cannot be applied to the case and it is needed to treat the carbody as three-dimensional structure (Box-type structure). In this paper, an analytical method is proposed to investigate vibration modes and responses of lightweight high-speed railway vehicles. The carbody is modeled as box-type structure, which consists of combination of plates and beams. The connecting condition of each components is satisfied by introducing artificial springs at their joints. The truck model contains the effect of the excitation input through traction devices and anti-yaw damper, and multiple input from right and left axle box is taken into consideration. Numerical results are compared to the measured data to examine the validity of the method.

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This paper describes the numerical results about squeal of disk brake. The squeal considered in this paper is low frequency squeal (1.8-2.5kHz), and has coupled vibration modes between rotor and caliper through pads. To investigate the mechanism of low frequency squeal, disk brake is modeled as a two-degree-of-freedom model. The brake system become unstable and occur the squeal when the coefficient of friction is relatively high. And to make the stiffness of caliper bigger, the squeal is restrained. From the analysis, it was made clear that the coefficient of friction between rotor and pads, and stiffness of caliper (especially the stiffness of trailing side) had grent influence to the low frequency squeal. So in design of the real brake system, these values are very important to restrain the low frequency squeal.

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Friction characteristics of braking material for safety gear of ultra-high speed elevator (1000m/min) was investigated by l/30 scale testing apparatus. The devaroped braking material is made of a compound with ceramics and metallic materials to prevent deterioration by shock and frictional heat. Its coefficient of friction is approximately 20% higher than the convenntional braking material, and its wear resistance is excellent. To clarify the friction characteristics of that for duplex type safty gear, breaking tests on the slided suraface of the rail specimen were also carried out. On the slided surface of the rail supecimen, friction coefficient is lower than that on the vergin surface. Its decreaseing rate of the devaloped breaking material is less than that of conventional one. The deveroped breaking material is better suited for duplex type saety gear.

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Skyscrapers require installment of high-speed elevators. As the elevators become faster, their ride comfort worsens because of cabin vibration due to disturbance. Therefore, an active vibration control system is often utilized to improve the ride comfort. In this study, a vibration control system and a neutral position control system are designed based on optimal control theory using the Active Mass Damper (AMD) to improve the ride comfort and prevent incorrect movement of the AMD. This report investigates the effect of a variable gain control on the movement of the AMD using computer simulation.

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In analyzing vehicle dynamics, it is useful to show animation of vehicle motion, in addition to charts of measured data. To visualize vehicle dynamics, however, displacement information should be prepared for all degrees of freedom. We are developing a system to achieve visualization by estimating necessary Information from minimum information. In the previous paper, we described the estilmtion of displacement by using a small sine wave input vibration. In this paper, we describe the estimation of displacement by a vertical track irregularity input vibration. We focus on the vibration amplitude dependency of air spring.

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Friction force or torque of mechanical brake is a state which is influenced by friction coefficient acting between brake disk and brake lining. If friction torque of mechanical brake can be measured or estimated, it will be possible to improve accuracy of brake force control, in the servo system which compensates for the variation of friction coefficient. This study presents a method to estimate friction torque acting between brake disk and brake lining in braking, using Inverse Systems.

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Natural Gas Hydrate (NGH) can be carried at much higher temperature than LNG (ca. 112K) by self-preservation effect. Thus, not only the running cost but also the initial cost of NGH production plant will be saved in comparison with LNG plant. We studied the NGH transporting system in the form of NGH pellet (NGHP). NGHP is solid in spherical shape and has good handling for loading to NGH carrier. A suitable combination of different sized pellets can improve the filling efficiency in cargo hold of NGH carrier.

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Recently, from the viewpoint of prevention of serious air pollution and global warming, reduction of harmful exhaust emissions and further improvement of thermal efficiency are requested. The electronically controlled hydraulic system for fuel injection and inlet/exhaust valve actuation on the diesel engine is expected as an effective method to reduce harmful exhaust emissions and fuel consumption because of achievement of optimum engine operation in response to changing conditions including engine loads and fuel properties. Now, we have mounted this system on the medium speed 4-cycle 3-cylinder diesel engine. It enables to control each fuel injection timing and each valve opening/closing timing independently. And even if low engine rotation, high fuel injection pressure and high speed of the valve actuation can be obtained. As the experimental result, it was found that using the electronically controlled marine diesel engine it was possible to improve thermal efficiency and to reduce harmful exhaust emissions synthetically at low load.

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This paper intoroduces a minivan with a newly developed hybrid system known as THS-C (Toyota Hybrid System-CVT). This hybrid system employs a highly efficient engine, a high performance exhaust emission control system, a super efficient CVT with metal belt, and a super efficient motor. System control of the engine, motor and CVT optimizes both the operations of the motor and the engine. With these improvements, this new vehicle achieves over 80% better fuel economy than the original vehicle and decreases drastically exhaust emission using precision control when the engine starts and stops.

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