Webs (such as paper, plastic film and metal sheets …etc) are wound onto rolls for distribution, processing, and operations. In the winding process, tension is one of the most important parameter for preventing the wound roll defects such as the star defect's and slippage which are detrimental to roll quality. In production field, it well known experimentally that linearly-decreased winding tension has the affects of preventing the wound roll defects. However, this tension pattern is not necessarily adapt to various types of conditions. On the other hand, Hashimoto present the optimization method of winding tension which is expressed by 3rd order sphne curve for preventing the wound roll defects. Thus we designed a wound testing machine to determine in-roll stress under deferent tension conditions. As a result, the predicted results by several tension conditions are compared with the measured data. Good agreements are seen between them.

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This paper describes experimental and theoretical studies of the fundamental characteristics of paper feeding mechanism in case of high roller rotating velocity. Experimental setup consists of driving rubber roller and driven steel roller. In experiment, velocity ratio and indentation of rubber roller are measured. In case of constant normal load, velocity ratio decreases as roller rotating velocity increases. The change of dynamic stiffness of rubber roller caused by viscoelasticity of rubber is considered in theoretical analysis. It is found that the change of dynamic stiffness of rubber roller influences the fundamental characteristics of paper feeding mechanism.

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This paper deals with an active control to suppress a flow-induced web flutter in a wide passage using pressure wave. A flexible web, as a controlled object, is supported at both ends in the passage and tensile force is applied. The web flutter is suppressed by the active control using the pressure wave from a loudspeaker. The loudspeaker set at downstream of the passage is driven with changing a gain and a phase-shift between the displacement of the web and the pressure. It is indicated experimentally that the proposed control technique suppresses the web flutter effectively and increases the critical flow velocity by about 20%.

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In this paper, a new flow-control device using movable plate actuators is developed and non-contact active feedback control is proposed to suppress the leakage-flow-induced sheet flutter. The sheet flutter is actively controlled and suppressed by the movable plates which change the air flow in the passage. As a result, it is experimentally shown that the sheet flutter is effectively suppressed by the proposed flow-control device and active feedback control method.

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This paper deals with an experimental study of self-excited vibrations generated on a thin film supported by an air tum bar with three slits. We examined circumferential pressure distribution of the air tum bar by measuring the pressure in a narrow gap between the air tum bar and the film experimentally. This study shows characteristics of the self-excited vibrations. As a result, there are two types of self-excited vibrations generated on the film. The self-excited vibrations are strongly coupled with fluctuating pressure. We discussed excitation mechanism of the self-excited vibrations of the film supported by the air tum bar.

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Using molecular dynamics, we simulated behavior of monolayer perfluoropolyether (PFPE) films coated on a solid substrate with respect to the approach and separation movement of another solid surface. Due to the presence of polar end groups, contact to Zdol films and separation from Zdol films occurred at shorter solid-solid distances than Z films. Liquid transfer to the solid surface was also less noticeable for Zdol than for Z. On the other hand, Zdol films exhibited strong adhesion and remarkable adhesion hysteresis between the approach and separation processes as compared with Z films.

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We measured the effect of ultraviolet (UV) inadiation to perfluoiopolyether monolayer lubricant films on the adhesive forte and the vertical elongation of the lubricant bridge formed between the lubricant films on magnetic disk surflices and a diamond tip. Two types of PFPE lubricants Fomblin AM3001 having polar functional end groups and higher UV ab9rptance, and Fomblin Z03 having non-polar functional end groups and less UV absorptance, and a chemically patterned Z03 lubricant film were sdected. It was found that Z03 was more susceptible to UV inadiation than AM3001 in terms of the adhesive force and the elongation of the lubricant bridge. It was also revealed that the local bonding ratio of the chemically patterned lubricant film mainly contributed to the adhesive force and the vertical elongation.

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In recent magnetic storage systems, the spacing between the flying head and the disk has been dramatically decreased to less than 10 nm for realizing ultra-high density recording. Therefore, it is very important to investigate the deformation and flow characteristics of the lubricant on the recording disk, especially the dynamic deformation of the lubricant, which is suffered from the repetitively applied pressure and shear stress by the flying head slider. In this paper, the dynamic behaviors of the ultra-thin liquid (lubricant) surface under vibrating flying head slider were numerically obtained. The dependence of the liquid surface deformation on the frequency of the stresses and the disk speed were clarified.

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Recently, the space between the flying head slider and the disk has been reduced to I Onm or less. Consequently, recording media with grooves such as discrete track media (DTM) and bit-patterned media (BPM), are considered to be some of the most promising media for achieving ultrahigh track densities. Thus, it is becoming increasingly important to analyze the static and dynamic characteristics of flying head sliders over DTM/BPM media using the molecular gas-film lubrication (MGL) equation. In this paper, we first use the perturbation method in the frequency domain to obtain not only the stiffness and damping produced by the air film but also the negative stiffness caused by the attractive van der Waals (vdW) force. The perturbation method was applied to a slider with 3 degrees-of-freedom (3-DOF) over an asymmetric groove-slider configuration, which caused a rolling motion in addition to translational and pitching motions. The dependence of the dynamic characteristics such as spacing fluctuations on the groove wave number (frequency) were numerically obtamed.

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In the present paper, we propose a modified Molecular Dynamics (MD) simulation method to analyze a gas flow in nanometer scale nanow area placed between walls. In the method, we use the difihise reflection model which assume that the wall is smooth and gas molecules reflect difihisely on the wall suifaces. This model is usually used in the direct simulation Monte Carlo (DSMC) method. Using the MD simulation method, the Couette flow problem, in which a gas flow is induced between two parallel plates separated by 10 nm and mnning opposite directions by 200m/s, is analyzed numeiically. Because the MD simulations are done by two dimensions as a first case, molecular number used in the MD simulation affects the flow velocity profile. A simulation case calculated using three molecules have good agreement with the flow velocity profile based on the Molecular Gas film Lubrication (MGL)theoiy It is eqectedthatagood result will be obtained by the MD simulation method extended to three dimensions.

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Recently, head-disk-interface(HDI) spacmg in hard disk drives(HDD) has been decreased to as low as 5 nm in order to achieve an ultra-high magnetic recording density. With the increase in magnetic recording density, the HDI spacing of the head has been reduced. To reduce the magnetic spacing, the active head slider with micro-thermal actuator was developed. The magnetic spacing of these sliders can be controlled in-situ during operation of the drive. The goal of this research is to clarify the slider hysteresis behavior of dynamic flying height (DFH) sliders. In this study, the slider hysteresis behavior was compared, varying the disk roughness. As a result, it was found the slider hysteresis behavior depends on the disk roughness.

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Liquid films which have a few nanometer thick are strongly affected by the disjoining pressure. When a liquid film on a horizontal flat solid surface is confined by another solid surface across a gas, instability of the film surface can be induced by the nonuniform disjoining pressure under several conditions. In this study, we focused on the instability caused by the curvature of the upper solid surface. The curvature makes the disjoining pressure spatially nonuniform, and consequently, the liquid film surface is deformed. The deformation speed depends on the solid-solid spacing and on the upper surface curvature.

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In this study, fundamental research on lubricant depletion due to laser heating in thermally assisted magnetic recording was conducted. In particular, the effect of lubricant film thickness as well as lubricant bonded ratio on lubricant depletion was investigated. The conventional lubricant Zdol2000 was used. As a result, it was found that the lubricant depletion characteristics due to laser heating depend largely on the lubricant film thickness and the lubricant film bonded ratio. In addition, it was suggested that the lubricant depletion mechanism involves the evaporation of the mobile lubricant molecules, when the maximum attained temperature is not very high. Another suggested lubricant depletion mechanism involves the thermocapiflary stress effect induced by the disk surface temperature gradient resulting from the non-uniformity of the laser spot intensity distribution.

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To further increase recording density of disk storage drives, laser-assisted magnetic recording can solve the fundamental programs of thermal fluctuation and is regarded as the keytechnology for achieving recording density of more than 1 Tb/in^2. In this technology, it is suggested that there is serious issues for the ultra-thin liquid lubricant films on the disk surfaces. Because they are heated to high temperature with laser beams. In this study, we focused on the thermal stability of the three lubricant film materials in laser-assisted magnetic recording. In other words, the behavior of lubricant film under the laser heating was investigated and discussed experimentally. As a result, it was found that the effects of lubricant materials as well as the laser irradiation conditions on the lubricant film depletion were clantied.

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The authors proposed a new actuator called "Nano-Motion Actuator (NMA)" for track following on a spin-stand that evaluated magnetic heads and media for high density recording. At the present time, effect of azimuth angle which causes between a center line of a head slider and a tangential direction of the track is actualized as a track pitch of the head becomes narrow. However, when a discrete track media (DTM) will be put to practical use, a new specification that should be large working distance exceeding 60 μm with a resonance frequency of over 5 kHz should be required. The authors proposed a new actuator which was consisted of a laminar piezoelectric element and a displacement amplitude mechanism. A new concept that was moving directions of the piezoelectric element and the actuator were at right angles to each other was applied to the amplitude mechanism. As a result, the new actuator will be able to evaluate new high density magnetic recording applied DTM on a future spin-stand system.

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This paper described the theoretical discussion of the risk curve, which shows the relationship between exceedance frequencies and their magnitude of the damage in a log-log scale. It is clear that the risk curves generally indicate Pareto distribution in large-scale damage of various types of hazardous events. Furthermore, Arrhenius equation expressed with the exponential function was used as the Probabilistic Disaster Characteristic Function (PDCF). Using the PDCF, Pareto distribution of the risk curve was theoretically verified.

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The pressure in the electric furnace did not increased unexpectedly, when we executed the explosive test. Therefore, we hypothesized that heat insulator of the furnace is effective in relief of the gas explosion, and the verification experiment was executed. As a result, it was found that the pressure in the furnace was influence by the heat insulator.

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In recent years, there has been increasing interest in developing high pressure processed foods, where hydrostatic pressure is used. We are developing very high pressure food processing equipment for adding of high value as food. For safety Certification, we want to make up safety concept pertaining to this equipment. We propose defense-for-security theory by analyses of traditional ways of high pressure equipments. This theory is method of validation of safety-related part of safety standards. The most important is pressure limitation device as last resort.

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This study is on construction of safety related to Very High Pressure Food Processing Equipment. Hazardous situation where human exposed to high pressure is connected directly with harm. Pressure vessel has a function to defense against internal pressure. However its defensibility has limit, it depends on material performance (i.e. the load must be controlled within the elastic range). So, it is necessary to control internal pressure not to exceed the defensibility. In the study, the defensibility prevent to hazardous situation is considered: (1) the complementary relationship model between safety by control and safety by material performance is shown, and (2) the safety proof construction is shown as a generic model.

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The Very High Pressure Food Processing Equipment is developing under the JST program operated by Niigata prefecture. In the equipment, the food is pressurized to about 400MPa through water. The major hazard source concerning on this equipment is "high pressure." If a certain amount of air is in vessel when the water is pressurized, it would take time to reduce pressure in relief process. Therefore it is necessary to achieve safety to implement functional safety: the air detection and the interlock system to avoid harm by misuse or controller trouble. On this paper, the air detection procedure is reported. The pressure is measured during pressurizing and is referred to the normal characteristic curve. And the delay of pressure rise in vessel is observed, it would be judged that air was in the vessel and the equipment stops pressurizing.

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A tire model utilized for motion analysis of vehicles traveling on dry sand was constructed. Tire force of a small size single wheel traveling on flat sand surface was measured under constant sinkage, slip ratio, and sideslip angle conditions. Experimental data showed that the norm of tire force at each sinkage could be approximated by a single curve as a simple function of slip ratio, not depending on sideslip angles. Furthermore the tire force could be decomposed into longitudinal and lateral directions by its slip direction. Taking advantage of these characteristics, tire-force calculating formula could be simplified. This tire model is possible to easily apply to driving analysis of vehicles on dry sand.

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The road bureau and the NILIM have been developing the next-generation road services which are composed of 5.8GHz DSRC and ITS on-board units, mainly focusing on AHS (Advanced cruise-assist Highway Systems) safety services. To follow the on-road verification tests and the Smartway 2007 Demo held at Metropolitan expressways in 2007, ITS-Safety 2010 Large-scale verification tests have been held in FY2008 as the joint verification tests in Tokyo and the local verification tests. This paper reports on the profiles of new services and the collaboration with the driving support system of another ministry as sensor data sharing.

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This paper aims to evaluate the effect of shorter reaction time and longer initial distance on safety of vehicle-platooning. Assuming high deceleration of the first car in the platoon, car-following movement of the rest of six vehicles were simulated with varying vehicle type, sequence, driver characteristic and so on. Numerical analysis on an actual domestic arterial corridor showed that both shorter reaction and longer distance contributed to safer vehicle-platooning, but the observed contribution was not significant. Especially passenger car just behind a heavy vehicle still came across high risk despite of the both proposed safety measures.

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The behavior of driver is formed by recognition, decision and operation. Driver has to grasp parameters such as changing of environments and movements of the automobile. There are chances that vehicle movements might be drivers' mental-workload and cause them to make mistakes in judgment and to disturb their operation of the car. In this report, we measured drivers' psychological reaction, and vehicle movements such as velocity, acceleration, and steering angle through the test. In order to consider time-series factors of psychological reaction, we used Wavelet Analysis from R-R interval of heart beat variability to clarify activities of autonomic nerve. As a result, we could specify the parameters of vehicle movements, which cause drivers' mental-workload. In addition, we could make a specific group of drivers who easily get the mental-workload from vehicle movements by using HQL Workload Sensitivity Questionnaire on drivers' individual characteristics.

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The driver while driving a motorcar is meeting the intersection, the crosswalk, the shoulder parked vehicle, the opposing vehicle, the signal, the weather, and the road environment, the traffic situation at the driving time etc. , and changes in the vehicle condition. The driver steers slowdown, a stop, departure, acceleration, the steerage from need corresponding to these environment changes. Because a driver continues such a driving, a burden increases a feeling, mental strain, and it becomes the cause that I cause fatigue and a concentration fall. There can be the thing tied to traffic accidents as a result of this. By this report, I measured vital reaction (a heartbeat count, bloodstream, quantity of sweat) that was load of the psychology that a driver received by run environment change and a speed change at that time and performed comparison in driving and nighttime driving in the day in many city sections of a roadside parking vehicle.

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Since elderly driver's traffic accidents increase with increasing of elderly population, the action of reducing them is called for urgent attention for us. As the result of driving actual condition survey by elderly drivers, they think that the most necessary system in the driver support is "night vision system". The study shows we study that elderly drivers secure the progress of safety and security feeling as they use a night vision system. Consequently, before we innovate its system in a car, they suggest that they can drive feeling safety and security in complicated pedestrians. We report the detail result in what follows.

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Kagawa Satellite Development Project promoted by Nohmi laboratory has been conducting development of Nano-satellite KUKAI in Kagawa University. KUKAI are dyad satellites, there are mother and daughter. KUKAI was launched by H-II A Launch Vehicle No. 15 at January 23, 2009. The orbit is sun-synchronous orbit of the altitude of 700km and the inclination 98.Odeg. It is currently operated at Kagawa University ground station, In this paper, reports electrical power condition data and temperature data of mother and daughter satellites an early date.

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The microsatellite SPRITE-SAT developed by Tohoku University was launched in January 2009. The mission is the observation of Sprite phenomena and Terrestrial Gamma-ray Flashes incidental on lightning discharges. In the 12 days after launch, the satellite is normally operated. But because it is damaged by a serious trouble at February 4, 2009, the data communication including uplink and downlink is not successful now. This paper shows the outlines of satellite system, flight operation results, and the reason of trouble.

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SOHLA-1 is a 50kg class space technology demonstration micro-satellite developed by Space Oriented Higashiosaka Leading Association (SOHLA). Osaka Prefecture University, Ryukoku University and Osaka University are engaged in the development with technological assistance of Japan Aerospace Exploration Agency (JAXA). This paper presents an overview of the development of the SOHLA-1 and a brief summary of the results obtained in the operation.

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These days, the super small satellites attract interest, as a way to launch observation and practical demonstration equipment. At Nakasuka laboratory, three super small satellites have been developed. Pico-satellite for Remote-sensing and Innovative Space Missions (PRISM) is the third satellite, whose main mission is the high resolution image acquiring with specially designed extensible boom. PRISM has succeeded in main mission on orbit, which means the beginning of practical use of super small satellite. In this research, the specification and the operation result of PRISM are introduced as the great suggestion of the next generation super small satellite.

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Intelligent Space Systems Laboratory, The University of Tokyo (ISSL) and National Astronomical Observatory of Japan (NAOJ) have been developing a small infrared astrometry satellite Nano-JASMINE (Nano-Japan Astrometry satellite Mission for INfrared Exploration). In order to acquire accurate star position data, Nano-JASMINE should be stabilized to less than 740 mas/8.8s accuracy during observation. Since this level of accuracy is much higher than that required to small satellite developed in the past, Nano-JASMINE needs high-performance bus system and brand-new control system. This research describes about the bus system of Nano-JASMINE and its current development status.

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In this paper, we propose an advanced formation flight (FF) method by uniting two types of devices: morphable beam devices (MBD) developed by Matunaga laboratory, and inflatable tubes, which present advantages of both free type and tether type. The MBD is a bendable arm with no actuator on itself, and the device can realize a lOOm long structure. We describe the concept design of 3-dimentional deployment formation flight satellite "TETRA" which is a 50kg and 50cm cubed microsatellite in order to demonstrate the FF technology using both the inflatable tubes and MBDs in orbit

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For Moon and interplanetary explorations, status checking/monitoring or investigating the target which is a spacecraft itself, its large deployable elements or a minorbody and so on, are needed during flight, and the authors proposed a separating nano-probe system to achieve the requirements. In this paper, design and development of the nano-probe system are reported with camera image analysis for a solar power sail technology demonstration mission of IKAROS of ISAS/JAXA.

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Since 1995, students of Tokai University collaborate with UAF's students in the project making rocket and payloads. This project including budget management was carried on only students between both countries. To observe ionospheric phenomena and to detect rocket attitudes, the SRP-5 rocket was launched at Alaska in January, 2009. Tokai University takes charge of two science missions as principal investigator. One is the measurement of magnetic variations associated with currents at the low ionosphere and the other is the measurement of ultraviolet rays to estimate ozone number density in the Arctic region. We have developed a UV sensor, a tri-axial fluxgate magnetometer and a sun sensor made by student hands. We describe here about rocket launch experiment and their results.

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CAMUI (Cascaded Multistage Impinging-jet) type hybrid rocket has been developed in Hokkaido University. The 3-dimensional shape of combustion chamber of hybrid rocket changes considerably during the operation because it is constructed of solid fuel itself. The shape of combustion chamber is related with the performance of the rocket directly, so it is important to understand the relationship between flow and shape. To clarify this issue, numerical simulations were conducted using three different 3D shapes. These shapes were measured from partially burned fuel blocks by the non-contact measuring system. These blocks were obtained by the combustion test where the blocks were taken out before they completely burn out.

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A lunar robot often requires its position relative to a lander during its activities. Although the lander is equipped with measuring devices such as stereo camera, the stereo camera does not work under shadowy environment. A three-point color marker is one of the resolutions to the issue. The three-point color marker is mounted on each segment. The lunar robot can measure its relative position from positional relationship between the three points of the marker. The marker system is simple but measuring accuracy is expected to be high enough and it is recognizable from distant place due to its mounted position.

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On the lunar surface the illumination environment is severe for capturing a well exposed image with digital camera. The sunlight is so intense there that clear shadows are created. The dynamic range required to the digital camera used such environment is well over that of currently available image censors. Therefore, the traditional image measurement technique is no longer applied to the lunar structure assembling. In order to resolve this issue, we have developed a new method which employs multiple images captured with different exposure values and the result of the test to verify the effectiveness of thiss method is shown.

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This paper describes a dynamics simulation of a humanoid robot on the moon. We are developing a humanoid robot simulator. This simulator is specialized for humanoid robot. Using this simulator, we evaluated walking performance on the moon. Humanoid robot walking controller parameters depend on gravity. As the gravity on the Moon is only one-sixth of that on the Earth, humanoid robot control parameters should be changed. In this paper we simulate a humanoid robot walking on one G and one-sixth G

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The solar sail that uses sunlight to flight in space is very valuable system, because it needs no fuel. In 2005, Cosmos-1 that adopts solar sail system was launched for the first time in the world. Now solar sail is noticed widely. There ure many studies about solar sail but most of them treat heliocentric-orbit. However it is necessary to study about earth-orbit, studies about earth-orbiting satellite are few. Then this study deals with earth-orbiting satellite and calculates the optimal orbit that makes orbital semimajor axis maximum. In this study, three-dimensional trajectories are calculated and realistic model was considered. Finally this study plans to propose one method that leads satellite to geostationary orbit.

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JAXA is developing the balloon-based operation vehicle as a new micro-gravity experimental device. The vehicle is carried to the stratosphere by a balloon and released. Micro-gravity environment is provided in the body during free-fall. The vehicle is retrieved in the sea because of safety and reuse. Therefore, there is the serious problem that the airflow dominate the decision of experiment. To solve the problem, pull-up maneuver is adopted after the free-fall experiment. The vehicle flies horizontally after the pull-up and guided to the sea area. This paper discussed about the effects of the maximum aerodynamic moment from the point of view of optimal control theory.

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This paper describes a method to predict the frequencies and modes of large structures by component modal tests. In this method, identical frequency measured by component modal tests for different tested components is considered frequency of structures. It is important to select a location where adds mass and stiffness to a tested component for accurate frequency measurements. In this method, peak frequencies of two masses give key information to select the optimal location. These masses are found by reducing mass matrices of a tested component and a structure to an arbitrary degree of freedom. The location is selected so that we separate peak frequencies of two masses from a target frequency of structures. Accurate mode measurements depend on which tested component is selected. This paper clarifies how to select a tested component to obtain accurate frequencies and modes of structures through component modal tests.

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L-605 (Haynes 25) alloy has been used for the mono-propellant structure and screen materials because of its excellent combination of high strength, up to 1100 K, and high oxidation resistance, up to 1400 K. However, deterioration of L-605 alloy caused by the effect of a high temperature environment with nitrogen and ammonia has been reported. Therefore, the alloy composition, hardness and microstructure of L-605 alloy were evaluated with and without heat treatment in a nitrogen gas atmosphere in order to investigate the degradation mechanism of the alloy. The hardness of the surface layer of the alloy increases with increasing heat treatment temperature. Concentration of chromium at the surface layer of the alloy was observed after being heat treated at 1173 K. In addition, chromium nitrides were detected in the alloy after heat treatment. These results indicate that the chromium nitride formation is a causal factor of deterioration of L-605 alloy.

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Large space structure should be constructed by robots not by human astronauts because of human safety and constructing cost. Besides, space manipulator should be deployable and foldable to reduce transportation cost and to put in rocket's payload. Tensegrity structure consists of rigid bars and flexible wires. It is suitable to make large structure and change its shape by changing wire's length. In this study, Applying tensegrity structure to extendable robotic arm is proposed. The robotic arm is composed of some tensegrity structural units that consist of 3 bars and 12 wires. When target edge position and attitude of the robotic arm are inputted, shape of the robotic arm can be determined by finding balanced shapes of each tensegrity units. A balanced shape of a tensegrity unit is searched and found by modifying target shape of the tensegrity unit.

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Japan Aerospace Exploration Agency (JAXA) develops a small demonstrator of solar power sail orbiter to demonstrate solar sail technology that utilizes photons from the sun for continuous acceleration and electrical power generation by thin flexible solar arrays. We proceed with "Interplanetary Kite-craft Accelerated by Radiation Of the Sun (IKAROS)" project, which planed to be launched in the summer of 2010. In this paper, we introduce the spread mechanism of solar power sail, and result of various tests or experiments of a proto-type model of IKAROS mission mechanism.

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In this study, crack propagation tests and crack opening tests were conducted to clarify property for the fatigue crack propagation of friction stir welded (FSW) 2024-T3 aluminum alloy. Specimens had FSW of inclined angle of 0 and 45 degtees to direction of applied loading. Results showed that crack opening stress was decreased and crack propagation rate was accelerated by the tensile residual stress around the weld line. Irrespective to the weld line angle, crack opening stress and crack propagation rate were almost same. And the da/dN-△K_<eff> curve of FSW and base metal specimens showed good agreement with each other.

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The nonslip condition between guided-pin and membrane is examined quantitatively for the guided-pin retraction mechanisms. The experimental results of the slip are compared with the one-dimensional slip model. Finally, the nonslip condition is discussed in terms of the guided-pin location and the properties of membrane.

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Gain degradation of a modular antenna due to module rotation, offset errors and curvature errors of a module is studied. Effects of these errors can be almost compensated in a single antenna by focus alignment adjusting mechanism, because they are low-order deformations. In order to investigate the effects of these errors, numerical simulations are carried out. The results clearly indicate that these errors cause antenna gain degradation of a modular antenna and they cannot be compensated.

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A fast responding Pressure-Sensitive Paint (PSP) using polymer/ceramic binder and image capturing technique called Phase Lock Method were used to visualize the unsteady pressure distributions on a capsule-shaped body undergoing the pitching motion. In addition, schlieren visualization using high-speed video camera was used to take a picture around the flowfield of the model, together with pitch angle measurement using a potentiometer. As a result, the strength and the location of vortices behind the capsule varies depending on the direction of the oscillating motion, and the base pressure distributions are related to the dynamic motion of the vortices from the edge of the capsule.

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Hayabusa sample return capsule (SRC) enters the earth atmosphere directly from the interplanetary transfer orbit with velocity over 12 km/s. Due to the extremely high aerodynamic heating up to 15 MW/m^2 exerted on the SRC, the total radiation from the SRC surface and the shock layer is estimated to be -4 to -6 visual magnitude from the ground 100 km apart. The radiation will give us a lot of information of surface phenomena and the interaction between the heatshield material and the high enthalpy air. In the present paper the reentry flight of the Hayabusa SRC and the development of the heatshield are briefly overviewed, and a preliminary ground spectroscopic experiment for correlating the surface phenomena and the radiation spectra is reported preparatory to the actual reentry of the SRC.

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Measurement technique enhancement program for high-enthalpy shock tunnel HIEST has been under going for the next five-year plan in JAXA. One of the focus of this program is accuracy evaluation of heat flux measurement under high-enthalpy stagnation condition above H_0=15MJ/kg (equivalent to flight Mach number 20 or higher). The heat flux measurement in HIEST will be compared with numerical simulation results and flight test results. Since there are many public ground testing data and flight data, Apollo configuration was selected as reference. Wind tunnel experiments has been performing in the impulsive facility HIEST. A configuration of this Apollo capsule model was AS-202 with maximum diameter of 250mm. To measure heat flux around the model, ninety-six miniature co-axial thermocouples were instrumented on the model. Angle-of-attack of the model will be varied from 0 degree to 30degree. Test will be performed with stagnation pressure of 20MPa to 60Mpa and with stagnation enthalpy from 3.5MJ/kg to 20MJ/kg. Real gas numerical simulation code with 3-D unstructured grid will be conducted. The distribution obtained at Re=1.0×10^6 shows fully laminar flow. While the distribution obtained at Re=2.6×10^6 shows natural transition at approximately Z=20mm.

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