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Wet multiple plate clutches consist of friction plates, on which a friction material is bonded, and mating plates that are plain metal plates. Since the frequency and the range of load in the field of forklift trucks vary widely and are more severe than those for passenger cars, the wet multiple plate clutches on forklift trucks are often damaged. Damaged clutches that were returned from the field typically had 3 types of symptoms: 1.Only the friction material was damaged, 2.Only the mating plates were deformed, 3.Both symptoms were observed. It was clear that the cause of these symptoms depended on the difference of the operating application and the strength criteria of each part. This showed that a design guide for wet multiple plate clutches considering the strength balance between the two parts according to the work application was required. The relevant flow chart of this design process was proposed.

As for automobile, the mass production period of Electric Vehicle(EV) has begun by the rapid progress of the battery performance. But for EV- Motorcycle(MC), it is limited for the venture companies' releases. The design and evaluation methodologies are not yet established or standardized so far. This paper provides the practical and the experimental examples. To study the feasibility of EV-MC, we developed the prototypes in the present technical and suppliers' parts environments, and evaluated them by the practical view of the MC usage. The developed EV-MC has the equivalent driving performance of the 250cc internal combustion engine(ICE)-MC and a cruising range of 100km in normal use. In the prototype development, the reliability and the ability of protection design of the battery in the whole vehicle against the environmental loads are mainly studied, especially, heat and cold, water, shock, and the accident impact.

Generally, it is thought that control is simpler than an Internal Combustion Engine (ICE)-Motorcycle(MC) as for the Electric Vehicle(EV) type MC. However, there is few characteristic to the ICE-MC to the EV-MC and it cannot get good performance without control for EV-MC. We study the methodology for design and evaluation an EV-MC. In this approach, we developed the prototype EV-MC having manual transmission. In our study, we think that EV-MC having manual transmission is feature in comparison with other general EV-MC. From this feature, we had to develop the function control in addition to standard EV-MC function control. This paper provides a function control for EV-MC having manual transmission. In this paper, we arrange the problem points of EV-MC which put electric propulsion motor and manual transmission together at first. And report the result that studied a method to solve the problem points.

With an increasing number of vehicles, the reduction of traffic noise emissions becomes a greater social requirement. On the other hand, as users' tastes for motorcycles have diversified, it becomes important to develop and supply products to meet customers' requests within a short period. Therefore, it is a key factor to efficiently develop motorcycles which conform to the noise regulations. This paper describes concrete examples of currently utilized noise-source proving methods and noise reduction methods for motorcycles.

Electronically controlled suspensions are expected to improve driving performance as the damping characteristics of the suspension can be adjusted in real time to respond to road conditions. This paper reports the results of testing the suspension control logic for improving ride quality, especially when driving on rough roads, using an internally developed riding simulator. The skyhook theory is widely known as a control logic for reducing vibration when driving a four-wheeled vehicle on a rough road, which we utilized in our riding simulator to examine the vibration reduction effects when applying control logic for motorcycle suspensions. The test results show that the skyhook theory can be applied in motorcycles. However, sensors for suspension systems that can be installed in mass-produced motorcycles are severely limited in terms of cost and space.

The power train system for Utility Vehicles (UVs) or All-Terrain Vehicles (ATVs) mainly consists of a rubber V-belt CVT. The adjustment of the CVT specification requires many steps to realize the shifting operations of the CVT so as to satisfy the acceleration feeling of the driver. In this paper, we report on the simulation technology that predicts the transient behavior during an acceleration of the vehicle equipped with a belt tension clutching CVT, which has both functions of the shift operation and the clutch action. By using the developed simulation technique, it has become possible to adjust the CVT specifications efficiently.

The Advanced ECS is under development for the purpose of saving fuel, improving safety, and cabin comfort. In FY2006 study, basic components (i.e. MDC, OBNOGS, desiccant units, and CO2 removers) have been improved and their performances evaluated including resistance to environmental condition (i.e. vibration). In addition, the suitable system configuration for a 90-seats aircraft has been considered to evaluate the feasibility of the system. In this paper, we show the results of the evaluated performances based on prototype components, and the analytical study of a revised system configuration.

“ASKA” developed by National Aerospace Laboratory (NAL) is a quiet, short take-off and landing (QSTOL) research aircraft adopting upper surface blowing (USB) concept as a powered high lift system. To achieving sufficient STOL performance by augmenting stall angle of attack and roll control power, blowing BLC technique was applied to the outboard leading edges and ailerons.Supplied high pressure air to save the BLC piping space,the BLC system which was fit for use of high pressure air was developed. The BLC system, in which BLC air is discharged by a series of discrete jets from small drilled holes (0.8 ∼ 3.0 mm in diameter) arranged in a raw, is one of the unique features of the aircraft. In this paper, the summaries of aerodynamic development of the BLC system are described except for the air piping system.

One of the important feature in the Environment Control and Life Support System required to support long duration mission at the Space Station is an oxygen supply for the human metabolism. The recovery of oxygen from the concentrated carbon dioxide through chemical methods will give significant advantage to the Space Station by reducing the supply requirement of the consumables, such as oxygen bottles. Oxygen recovery plants using the Bosch reaction and the Sabatier reaction are experimentally developed and tested. The Bosch reaction has been considered to produce carbon and water directly from carbon dioxide by the hydrogenization process. But it seems to proceed through two steps with carbon monoxide as the intermediate product. Also the total production rate is relatively low and the carbon deposited is less solid. The Sabatier reaction requires two steps to achieve carbon and water, with methane as the intermediate product.

This paper describes a numerical analysis method for predicting the brake squeal using the Substructure Synthesis Method. This method is more accurate than the classical method based on the mass-spring system, and simpler than the analysis of all the brake system by FEM. The squeal studied here is focused the one occurring in the low frequency range and its mechanism is due the structural instability of the brake assembly. First, some experiments were carried out in order to grasp the brake squeal phenomenon. These experiments made clear the following items. (1) The low frequency brake squeal occurred at 850Hz. (2) The vibration mode shape had 5 nodes fixed in a space. (3) The brake squeal became maximum at 0.3 - 0.5 (MPa) liquid pressure under the constant temperature condition. (4) The higher the temperature of the pad was, the stronger the brake squeal was under the constant liquid pressure condition.

In order to design a well-balanced truck frame, optimization of not only the stiffness of the entire body and stress of each member, but also the internal force of each member is necessary, including the effect of a rear body mounted on the frame. This paper proposes a new parameter, “torsional stiffness share rate,” that directly correlates the contribution of member torsional stiffness to frame torsional stiffness with the internal force of the members as to torsion of the truck frame. The merits of the torsional stiffness share rate are shown in comparison with the strain energy share rate and the stiffness contribution rate. The results of experimental and FEM analyses of the torsional stiffness share rate are also presented.

In case of all-terrain vehicles (ATVs), which have characteristics of both motorcycles and cars, the effect of the rider movement can not be ignored when analyzing ATVs' behavior. We have developed a simulation system of an ATV with rider operations, which are throttle control and rider movement, by using multibody dynamic simulation software. To quantify the rider operations and verify the validity of the simulation system, we have conducted experiments and simulations on a sport-ATV in two jumping patterns. In this paper the results of comparison between simulation and experiment are reviewed. Then, we report the analysis results of the effects of the rider operations and the ground profile to ATV jumping behavior with using the simulation system.

Water is one of the most valuable items in the closed environment such as the space station. It will be used for human habitation and various experiments. However, it will be not supplied from the earth. Therefore, water reclamation is one of the most indispensable technologies in the space station. The water treatment processes used to be combinations of the membrane separation technologies of pre-filter (PF), ultra-filtration (UF) and reverse osmosis (RO) which has been developed for the salt-to-fresh distillation technology. One the other hand, more efficient hydrophobic membranes have been developed recentry. Using these new water treatment technology of hydrophobic membranes, the membrane distillation (MD), combined with the conventional water treatment process in now being investigated for water reclamation. The MD is expected to be most important process of the water reclamation system integrated into the space station in the future.

In this study, we efficiently predict the vibration response of a design shape at a low computational cost in the early development stage, select design proposals with good characteristics from many proposals devised by the designer at the early stage, and forward them to the next stage to achieve the front-loading of development while increasing product value. The application of participation factor (PF) focusing on the response at a specific part for vibration evaluation of a motorcycle frame is described. To reduce the motorcycle frame vibration, an eigenvalue analysis was performed, and appropriate design change proposals were efficiently selected using partial participation factor (PPF), an index showing the relevance of vibration of specific parts or positions. Using the PPF, we extracted which vibration modes considerably contribute to the vibration response of the part of interest.

This technical paper reports the development of an automatic defect detector utilizing deep learning for “polished skins”. Materials with a “polished skin” are used in the fabrication of the external plates of commercial airplanes. The polished skin is obtained by polishing the surface of an aluminum clad material, and they are visually inspected, which places a significant burden on inspectors to find minute defects on relatively large pieces of material. Automated inspection of these skins is made more difficult because the material has a mirror finished surface. Defects are broadly classified into three categories: dents, bumps, and discolorations. Therefore, a defect detector must be able to detect these types of defects and measure the defects’ surface profile. This technical paper presents details related to the design and manufacture of an inexpensive automated defect detector that demonstrates a sufficiently high level of performance.

This paper describes a simulation of the lubricating oil flow in a motorcycle oilpan using a CFD technique in consideration of oil suction and oil return. In the technique, sink boundary and source boundary were used to simulate oil suction and oil return, and a VOF method was used to simulate the free surface of oil. To validate the simulation, a simulation result was compared with experiment results of a prototype motorcycle. As a result, the time of the simulated oil pressure drop in main gallery when the motorcycle decelerated rapidly in a racing circuit was agreed with the measured one. In addition, to demonstrate the applicability of the CFD simulation, a case study of the shape optimization on the baffle plate in the oilpan was shown.

Nowadays, space crafts such as a space shuttle take the O2 gas for crew respiration from the earth. However, for long periods of stay in space and far missions such as to the moon, it is not possible to carry sufficient amounts of oxygen. Therefore, there is need to establish other methods of supplying the extra O2 required by the crew under such circumstances. The CO2 reduction system is one method to generate O2 in space.

The Japanese Experimental Module (JEM) Pressurized Module (PM) is a facility where astronauts conduct experiments or control the total JEM facility. Inside the PM, the air composition, temperature and humidity are controlled so as to be comfortable for astronauts' activity all the time. The verification of the on-orbit performance of the functions constituting a manned space system is one of the critical points. Computational Fluid Dynamics (CFD) simulation technology is utilized to characterize and investigate the airflow in the JEM for various operating conditions. The development of a successful CFD model for International Space Station (ISS) operation is useful because there are always off-nominal and other contingency operations, which might occur and could be analyzed using an existing CFD model. This paper also presents the cabin ventilation test data obtained from the JEM flight module.

In motorcycles, the size and output performance of the engine itself has a major effect on the maneuverability of the motorcycle. In particular for cases where a high output engine is mounted on a lightweight frame, these effects are even more of a concern. In the case of developing a racing motorcycle with a high power engine, the behavior of the motorcycle differs depending on the output range used and there are a lot of cases where changes to the basic dimensions of the motorcycle as well as the main components are required. Here, there are a lot of cases where the rider and drive-able courses are limited to compatibility with distinct specifications and when considering use as a general mass production motorcycle by riders with varying levels of skills and in various environments, it difficult to determine how to provide support.

A driving simulator capable of duplicating the critical sensations incurred during a spin, or when a driver is engaged in drift cornering, was constructed by Mitsubishi Heavy Industries, Ltd., and Hiromichi Nozaki of Kogakuin University. Specifically, the simulator allows independent movement along three degrees of freedom and is capable of exhibiting extreme yaw and lateral acceleration behaviors. Utilizing this simulator, the control characteristics of drift cornering have become better understood. For example, after a J-turn behavior experiment involving yaw angle velocity at the moment when the drivers attention transitions to resuming straight ahead driving, it is now understood that there are major changes in driver behavior in circumstances when simulator motions are turned off, when only lateral acceleration motion is applied, when only yaw motion is applied, and when combined motions (yaw + lateral acceleration) are applied.