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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.

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.

We developed active control more suitable for sports riding than the previous electronic stability control system for enjoying sports riding by many users. One of them, the traction control system S-KTRC (Sports Kawasaki TRaction Control) uses the sensor output like not only the slippage calculated from the front and rear wheel speed but also engine speed, throttle position, and gear position etc. As the result, conditions of the motorcycle and rider's intention are calculated by ‘Motorcycle model’ in the ECU continuously. By this ‘Motorcycle model’, S-KTRC confirms the real time conditions and predicts the succeeded condition, every 5milliseconds to decide to govern torque. The ABS system KIBS (Kawasaki Intelligent anti-lock Brake System), it is possible to control the rear wheel's lift by using the pressure data of the front brake at the sudden braking operation.

At the upstream part of the Three-Way Catalyst (TWC) an O₂ sensor (UpO₂S) is used for O₂ Feedback Control (O₂F/B) that controls the air-fuel ratio (A/F) close to the stoichiometric level. O₂ sensor has a bit of individual characteristic difference as for the switching the excess air ratios of output (λ shift). This phenomenon becomes remarkable according to the effects of unburnt elements in exhaust gas. Despite the O₂F/B implementation, A/F isn't controlled to the stoichiometric level and the conversion efficiency of the TWC could be lower. Maintaining a higher level of TWC conversion efficiency requires more accurate A/F control and corrections of the UpO₂S λ shift issue. Therefore, using an O₂ sensor at the downstream part of the TWC (DownO₂S)~where the effects of unburnt elements in exhaust gas are smaller~can be an effective way to restore these challenges.

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.

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.

The feasibility study of the thermal control system for medium size or large size satellites was conducted to investigate the capabilities and specifications of devices such as cold plates, a radiator, a mechanical pump, and so on. In the first step of the system development demonstration, the cold plate was selected to investigate the performance among these devices. In this paper, the system concept of the advanced single-phase fluid loop and the evaluation by numerical analysis and experiments are described.

A Temperature and Humidity Control (THC) assembly an essential system in order to provide comfortable environment for crew members in Japanese Experiment Module (JEM). Development of an engineering model (EM) and a proto model (PM) of JEM THC assembly started from March 1991 and completed on March 1995 successfully. In this development phase, it is called JEM EM phase, qualification test of THC was conducted to verify the THC design. This paper presents JEM THC design and an outline of the assembly model development.

This paper describes results of the thermal-hydraulic performance experiment system (THYPES) of the two-phase flow loop thermal control system using the test rocket which can maintain a gravity level of 10-4G for about six minutes. Feasibility study of this system had been conducted for loading into a experiment module of test rocket TR-IA No. 3. In 1991, engineering model of the experiment system was designed and manufactured in order to investigate its function, performance, and endurance against launching conditions. In 1992, flight model of the experiment system was designed and manufactured. The following tests were conducted so as to ensure the capability and compatibility of THYPES; functional test, performance test, environmental test, and interface tests between the experiment system and rocket avionics section. The experiment was performed on September 17, 1993 and the results are evolved.

The Japanese Quiet Short Take Off and Landing experimental aircraft named ASKA was developed and flight tested during 1977 till 1989. The control system hard and software were examined by the functional mock-up with using the actual hardware. The small longitudinal limit cycle was observed in the closed loop test when the Pitch Control Wheel Steering software was on in the mock-up testing. In this paper, first, the method to analyze and to expect the limit cycle based on the describing function was shown. The limit cycle was induced due to the nonlinearities in the automatic control mechanism. The nonlinearities in the hardware were examined to make the model to simulate the system on the computer. The method was shown effective to predict the limit cycle in the mock-up. Second, with using the flight measured dynamics, the limit cycle was concluded as on border line between existing and not, which coincides with the actual flight result.

“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.