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After the turn of the century, growing social attention has been paid to environmental concerns, especially the reduction of greenhouse gas emissions and it comes down to a personal daily life concern which will affect the purchasing decision of vehicles in the future. Among all the sources of greenhouse gas emissions, the transportation industry is the primary target of reduction and almost every automotive company pours unprecedented amounts of money to reengineer the vehicle technologies for better fuel efficiency and reduced CO2 emission. Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

Suspension is an important chassis part which is vital to ride comfort [1]. However, it is difficult to achieve our targeted comfortability level in a short time. Therefore, improving efficiency of damper development is our primary challenge. We have launched a project which aims to reduce the workload on developing dampers by introducing analytical approaches to the improvement of ride comfort. To be more specific, we have been putting effort into developing the damping force prediction, the vehicle dynamics prediction and subjective rating prediction. This paper describes subjective rating prediction method which output a subjective rating corresponding to the physical value of the vehicle dynamics with deep learning. As a result of verification using objective data which was not used for learning process, DNN (Deep Neural Network) prediction method could fairly precisely predict subjective rating of the expert driver.

The thermal design of the LUNAR-A spacecraft, investigating the internal structure of the moon, is a challenge due to the widely varying thermal environments. A passive thermal control philosophy of radiators, multilayer insulation (MLI) and heaters was used for the LUNAR-A thermal design. Verification of the design was performed separately for the major spacecraft modules which consisted of a main structure, a propulsion subsystem and penetrators. As consequence, acceptable thermal performance can be expected for all phases of the mission. This paper describes the thermal design, analysis, thermal model testing and in-orbit temperature predictions.

The satellite ‘HALCA’ was launched in February 1997 by the Institute of Space and Astronautical Science (ISAS), Japan. HALCA is a scientific satellite with a large deployable antenna to make experiments on space VLBI. The deployable antenna, developed under the requirements of large aperture area and accurate reflector surface, is formed of complicated structures and lots of mechanisms. Though heat exchange in the antenna was complicated and difficult to evaluate, antenna thermal performance in orbit was within expectations and all mechanisms were adequately controlled until the antenna deployment. This paper describes thermal control design of the large deployable antenna, thermal design verification in the thermal balance test, and evaluation of performance in orbit.

This paper describes a new passive thermal control device-a Reversible Thermal Panel (RTP)-which changes its function reversibly from a radiator to a solar absorber by deploying/stowing the radiator/absorber reversible fin. The RTP consists of Highly Oriented Graphite Sheets (HOGSs), which have characteristics of high thermal conductivity, flexibility and light weight, as thermal transport units, which can transport the heat from equipment to reversible fin, and of a Shape - Memory Alloy (SMA) as a passively rotary actuator to deploy/stow the reversible fin. The RTP prototype model was designed and fabricated using HOGSs, a honeycomb base palate, and a prototype reversible rotary actuator. The heat rejection performance of the RTP as a radiator and the heat absorption performance as an absorber were evaluated by thermal vacuum tests and thermal analyses. The autonomous thermal controllability achieved using the prototype rotary actuator was also evaluated.

The present paper addresses the development study of expander cycle Air Turbo-Ramjet (ATR) conducting in the Institute of Space and Astronautical Science (ISAS) in cooperation with Ishikawajima-Harima Heavy Industries Co., LTD(IHI). The analytical study on the various cycle derivatives of ATR engine applying for a space plane has been presented in IAF congress held in Brighton 1987. Of which we selected the expander cycle ATR with intake air cooler and made the long-term research plan to assess its feasibility. The development study is going to be implemented by three steps of verification test, (1) sea level static test, (2) hypersonic simulation test with wind tunnel and (3) actual flight test with a flying test bed. We are now in the first step which was initiated in 1988 and will be accomplished in 1991.

The MUSES-B spacecraft will be launched in 1996 by the Institute of Space and Astronautical Science (ISAS). Its primary mission is experiments on space Very Long Baseline Interferometry (VLBI) for radio astronomy using a large deployable antenna. A challenging thermal design must be compatible with a wide range of sun angle and an 86 minute eclipse. The thermal design and verification has been performed separately for the major modules of the spacecraft; a main structure, a deployable antenna and Reaction Control System (RCS). Special attention is paid to the exposed RCS whose solar input varies significantly depending on the sun angle. This paper describes the thermal design concept for MUSES-B and verification results of its thermal model test focusing on the main structure and the RCS.

An onboard simultaneous measuring method of solar absorptance αS and total hemispherical emittance εH for thermal control materials is proposed. This method allows to determine αS and εH simultaneously by giving different levels of input power to a sheet heater attached to the sample, and there is no need to use the values of the mass or the specific heat of the sample materials for the data reduction. In order to verify this method on the ground, the parameters αS and εH are measured for three kinds of thermal control materials.

The authors worked in the Engine Department at Nakajima Aircraft Co. from 1936 to 1945. Nakagawa was in the Engine Design Department, where he was involved in designing the air-cooled, radial double-row 14-cylinder 1,100 hp Sakae Model 20 engine and the radial 18-cylinder 1,800 - 2,000 hp Homare engine. Mizutani was a field engineer for these two engines and other engines. During that period we gained much experience in fuel and lubrication systems. Before the authors joined Nakajima, the company's engine development team had already developed a carburetor-based fueling system, which was subsequently used in all Nakajima engines. From 1941 on, all newly designed engines had to use 87-92 motor octane fuel by order of the Army and Navy. It was a very difficult task to change the engine specifications to meet this requirement, particularly for the Homare engine, which was initially designed for 100-octane fuel. The authors explain various steps taken to overcome this difficulty.

A number of reports have been published in recent years concerning research work that is underway in Europe. America and Japan on navigation systems for vehicles. The systems reported on to date employ a variety of position detection sensors, such as geomagnetic sensors, gyrocompasses and loran receivers. However, the literature contains virtually no reports of automobile navigation systems that make use of a Global Positioning System (GPS) as a means of detecting and determining the location a vehicle. The authors have developed a GPS automobile navigation system that is intended to be one subsystem of a cinorehensive on-board information system. The total system incorporates car telephone data communication capabilities as well as various functions for centralized operation of the vehicle equipment. This navigation system can accurately locate a vehicle's position using position data received from GPS satellites together with data supplied by geomagnetic sensors.

A scoping thermal analysis was done to evaluate the general feasibility of capillary pumped heat engines. The analysis was motivated by recent advances in nanoscale materials science that have made it increasingly practical to manufacture high porosity wicks with a median pore diameter on the order of a few nanometers. Capillary pumped heat engines are shown to be generally feasible for wick evaporation rates equivalent to about 1 watt per square centimeter when wick material thermal conductivity on the order of a few W/m-K is assumed. A compact heat engine architecture, referred to as an integrated capillary engine, is introduced.

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.

Because of rising demands to improve aerodynamic performance owing to its impact on vehicle dynamics, efforts were previously made to reduce aerodynamic lift and yawing moment based on steady-state measurements of aerodynamic forces. In recent years, increased research on dynamic aerodynamics has partially explained the impact of aerodynamic forces on vehicle dynamics. However, it is difficult to measure aerodynamic forces while a vehicle is in motion, and also analyzing the effect on vehicle dynamics requires measurement of vehicle behavior, amount of steering and other quantities noiselessly, as well as an explanation of the mutual influence with aerodynamic forces. Consequently, the related phenomena occurring in the real world are still not fully understood.