The purpose of a powered wheelchair driving simulator is to decrease the time and effort in the process of clinic, research and development. In this paper, the design concepts of our driving simulator for research and development use are explained. To design the simulator's software and hardware, two following experiments were conducted. 1: The driver's horizontal field of view was measured. While making a right turn at a corner of a corridor, the movement of the driver's gazing point was measured. From this result, the maximum and minimum values of gazing point movement were analyzed to design the simulator's angle of view. 2: Motion cues such as acceleration and vibration were measured. The characteristics of these motion cues were analyzed to design the motion system. From the experiment results, a driving simulator of a powered wheelchair was developed. To evaluate the driving simulator, the experiment for comparing with a real powered wheelchair driving was conducted. Evaluations improved by the components which were specially designed for the driving simulator.

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In this paper, we discuss the difference of driver's characteristics. Nowadays, driver assist systems are developed. It is very important to develop an effective driver assist system. We focus our attention on steering maneuver. We performed the experiment using the actual car. In the experiment, we measured not only a vehicle state but also the force acting on steering wheel and the motion of driver's arm. The six-degree-force transducer on steering wheel is newly developed. The motion capture system using supersonic wave is adapted. We found three kinds of characteristic maneuvers. First, it is the difference of steer angle. A beginner driver steers with high frequency. On the other hand, an expert driver steers without high frequency. Next, we investigated the location of grabs on steering wheel of each subjects. The beginner grabs particular place of steering wheel. They don't cross their arms during cornering. Finally, we found the difference of characteristic about pushing and pulling force on steering wheel.

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We conducted driving simulator experiments with 15 participants to identify factors related to drivers’ judgment of when and how to brake. We set up a situation in which a subject vehicle encountered a target vehicle at an open non-signalized intersection to simulate a crossing collision. Drivers in the subject vehicle were instructed to apply the brakes when they felt danger. Factors investigated were azimuth angle to the target vehicle, position of target vehicle when the subject vehicle arrives at an intersection, visual angle of target vehicle, and relative distance between subject vehicle and target vehicle. We analyzed both their time differentials and increase rates. Statistical analysis indicated that the factors most closely related to the drivers’ braking judgment are relative distance between subject vehicle and target vehicle, and azimuth angle to the target vehicle.

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This paper studies a tracking line of battery SOC (State of Charge) which indicates battery energy remaining along with an up-hill drive way in Death Valley with a number of start-stop modes to its simulation on an emission chassis dynamometer with a gradient road load. A method of spline interpolation smoothes apply to set a road gradient data for a chassis simulation test. It was found that the SOC in the chassis simulation matches the SOC in a real world test. The paper mentions a quantitative evaluation to the simulation results based on Mahalanobis distance method.

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Rolling stock has generally been inspected and maintained on the basis of preventive maintenance. However, the reliability of sensors and information technology has drastically improved and, with this background, the objective of this research is to develop a condition monitoring system for the bogies of Shinkansen cars. This paper describes two algorithms for detecting faults in some parts of bogies. These algorithms are based on the statistical analysis of vibration acceleration during some periods. One algorithm detects the difference in the vibration peak distribution between normal operation and operation with faulty parts. The other algorithm compares the vibration states between the front and rear bogies in the same car when one bogie has faulty parts. To examine the details of the vibration characteristics of the bogie with some faults, experiments simulating some faults in bogie parts are conducted in the rolling stock field simulator at Komaki Research Center of JR Central. Through this experiments and analysis, we can demonstrate the reliability and validity of the schemes developed in this study for monitoring the conditions of Shinkansen bogies.

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Currently, container ships move cargo with minimal participation from external trucks. However, there is slack time between the departure of container ships and the completion of cargo handling by container ships without the participation of external trucks; therefore, external trucks can be used to move cargo without delaying the departure time. In this paper, we propose a solution involving the control algorithms of transfer cranes (TCs) because the efficiency of yard operations depends largely on the productivity of TCs. TCs work according to heuristic rules using the forecasted arrival times of internal and external trucks. Simulation results show that the proposed method can reduce the waiting time of external trucks and meet the departure time of container ships.

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The activation mechanism of motorcycle weave mode is clarified within the framework of the energy flow method, which calculates energy flow of mechanical forces in each motion. It is demonstrated that only a few mechanical forces affect the stability of the weave mode from among a total of about 40 mechanical forces. The activation of the lateral, yawing and rolling motions destabilize the weave mode, while activation of the steering motion stabilizes the weave mode. A detailed investigation of the energy flow of the steering motion reveals that the steering motion plays an important role in clarifying the characteristics of the weave mode. As activation of the steering motion progresses the phase of the front tire side force, and the weave mode is consequently stabilized. This paper provides a design guide for stabilizing the weave mode and the wobble mode compatibility.

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This study uses the energy flow method to analyze how structural flexibility affects the motorcycle wobble and weave modes. Lateral bending of the front fork and torsion of the main frame affect the wobble mode stability. These are based on the gyroscopic effect of the front wheel in the steering motion by considering structural flexibility. At high speeds, lateral bending of the front fork and torsion of the rear swing arm more significantly affect the weave mode stability. These are primarily due to the phase changes of the external force generated by the yaw rate in the lateral motion. The phase change of the yaw rate force in the lateral motion originates from the phase change of the tire side forces.

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Disturbances decrease vehicle stability and increase driver's mental and physical workload. Especially unexpected disturbances such as lateral winds have severe effect on vehicle stability and driver's workload. This study aims at building a driver model of steering operations in lateral wind toward developing effective driver assistance system. First, the relationship between the driver's lateral motion and its reactive quick steering behavior is investigated using driving simulator with lateral 1dof motion. In the experiments, four different wind patterns are displayed by the simulator. As the results, strong correlation was found between the driver's head lateral jerk by the lateral disturbance and the angular acceleration of the steering wheel. Then, we build a mathematical model of driver's steering model from lateral disturbance input to steering torque of the reactive quick feed-forward steering based on the experimental results. Finally, validity of the proposed model is shown by comparing the steering torque of experimental results and that of simulation results.

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In recent years, air-spring-type tilting vehicles, which use air springs as the car-body tilt mechanism, have been employed, even in Shinkansen trains, to increase the operation speed on curved sections. On a test train running at a speed of about 300 km/h with the tilt mechanism, however, it was found that the car-body roll and lateral vibrations increased in compound curves where the plane and vertical curves overlapped. In this study, an analytical model of the air-spring-type tilting vehicle is developed, and a numerical simulation is carried out to clarify the high-speed curving behavior in a compound curve. Then an antiroll damper, which is installed between the car-body and the existing anti-rolling device, is examined as a countermeasure to reduce car-body vibration. As a result, it is shown that the vibration occurring in the compound curve is caused by the centrifugal force generated by the passage of the train on the vertical curve and the imbalance in stiffness between the left and right air springs during tilting. It is also shown that an antiroll damper has a potential to suppress the increase in car-body vibration in compound curves.

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