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In recent years, the number of reported traffic accidents due to sudden deterioration in driver’s physical condition has been increasing, it is expected to develop a system that prevents accidents even if physical condition suddenly changes while driving, or reduces damage through vehicle body control. For this purpose, it is necessary to detect sudden changes of the driver’s physical condition, and research is being conducted widely. Among them, it is reported that some of such changes may appear in the heartbeat interval. In other words, by acquiring the driver’s heartbeat interval in real time, it may be possible to detect the sudden changes, and reduce traffic accident. Even if a traffic accident occurs, the damage can be reduced by emergency evacuation immediately after detecting sudden changes.

This paper experimentally and analytically evaluates the heat rejection/retention performance of a reversible thermal panel (RTP) which can autonomously change thermal performance depending on its own thermal conditions. The RTP is considered as a candidate methodology for thermal control of Venus mission, PLANET-C, in order to save survival heater power. An RTP prototype was tested and evaluated. An analytical thermal model of the RTP was also developed, and basic performances of the RTP were evaluated. Thermal performance of the RTP when applied to the longwave camera (LIR) of the PLANET-C was evaluated with an analytical thermal model as functions of fin deployment directions and rear surface properties of the RTP's fin. The analytical results showed that the RTP can save heater power in comparison to a conventional radiator.

In a previous study, we developed and validated a new driving posture focused on biomechanical loads for physical fatigue reduction in static long-term sitting. In this study, the posture was evaluated in dynamic long-term driving condition by qualitative and quantitative measurements. The results showed physical fatigue of the new posture was halved in comparison with the one of the conventional posture in same car by subjective evaluations. Physiological indices had same tendency with subjective evaluations. From the results, we extracted seven physiological indices as good measures of physical fatigue while driving. Therefore, fatigue reduction of the new posture was qualitatively validated by physiological measurements.

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.

Variable emittance radiator, called SRD, is a thin and light ceramic tile whose infrared emissivity is varied proportionally by its own temperature. Bonded only to the external surface of spacecrafts, it controls the heat radiated to deep space without electrical or mechanical parts such as the thermal louver. By applying this new device for thermal control of spacecrafts, considerable weight and cost reductions can be achieved easily. In this paper, the new design and the new manufacturing process of the SRD and its optical properties, such as the total hemispherical emittance and the solar absorptance, are described. By introducing this new design and manufacturing process, the weight of the SRD is easily decreased, keeping its strength and the optical properties.

A lightweight 100 W-class deployable radiator with environment-adaptive functions has been investigated. This radiator - Reversible Thermal Panel (RTP) - is composed of flexible high thermal conductive materials and a passive reversible actuator, and it changes its function from a radiator to a solar absorber by deploying/stowing the reversible fin upon changes in the heat dissipation and thermal environment. The RTP is considered one of the candidates of thermal control methodology for the Japanese Venus mission “Planet-C”, which will be launched in 2010 to save its survival heater power. In this paper, design and fabrication of the RTP proto-model (PM) and the test results of deployment/stowing characteristics in an atmospheric condition are reported. Thermal performance estimation with thermal analytical model of the RTP PM is also presented.

Fatigue resulting from long-term driving can be classified into physical and mental fatigue. Physical fatigue seems to be mainly caused by driving posture. The purpose of this study is to develop a new driving posture for reduction of causal factors of physical fatigue, that is, biomechanical loads caused by the posture. In this paper, driving posture was optimized by subjective optimizations of seat contours and biomechanical analysis considering necessary conditions for driving operations and forward view. The new driving posture was tested by subjective evaluations and pelvic movement measurements. It was found that the new posture reduced physical fatigue dramatically.

Ignition by Nanosecond Repetitively Pulsed Discharges (NRPD) at EXponential Increase of Minimum Ignition Energy (MIE-EXI) region under super lean SI engine conditions was studied. Fundamental experiments were conducted with a turbulent ignition test chamber with twin counter-rotating fans. The MIE-EXI region by arc discharge appeared over 6500 rpm of fan speed. In the MIE-EXI region (7000 rpm), successful ignition was achieved by establishing coupled ignition kernels with NRPD at 15 kHz although ignition was unsuccessful at 1 kHz. Results show that ignition by NRPD has potential advantages for lean burn applications. Preliminary engine test results with NRPD were also demonstrated.