The Japan Aerospace Exploration Agency (JAXA) makes the world's first solar power sail craft IKAROS demonstration of photon propulsion and thin film solar power generation during its interplanetary cruise. The spacecraft deploys and spans a membrane of 20 meters in diameter using the spin centrifugal force. It also deploys thin film solar cells on the membrane, in order to evaluate its thermal control property and anti-radiation performance in the real operational field. The spacecraft weights approximately 310kg, launched together with the agency's Venus Climate Orbiter, AKATSUKI on May 21, 2010. This is a Front-Loading of new key technical issues of extended solar power sail mission toward Jupiter and Trojan asteroids via hybrid electric photon propulsion. This paper presents the summary of development and operation of IKAROS.

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The novel asymmetric thermoplastic polyimide (ISAS-TPI) with space environmental stability was developed. The large area polyimide thin films (φ=20m) was fabricated with various electric devices for solar/solar cell hybrid sail "IKAROS" launched on May 21, 2010. IKAROS have completely been achieved the world's first solar sail mission.

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Japanese spin-type solar power sail IKAROS was launched in May 21st 2010 by JAXA, and the 20m-sized sail membrane was successfully deployed in June 2010. The deployment was achieved through two stages. In the first stage, a part of the membrane is unwrapped quasi-statically from the cylindrical spacecraft. In the second stage, the whole membrane is deployed dynamically from the spacecraft. During the design and development process of the sail membrane structure in last three years, the numerical simulation of the deployment dynamics had been one of the most important issues. In this paper, the pre-flight prediction of the deployment behavior in the second stage is summarized, and the flight data is compared with the numerical simulation.

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This paper briefly summarizes the trend of small satellite development activities in European community. Recently, the importance of small satellite development activity, especially in terms of education, is getting recognized in Europe and a large amount of organizations and institutions are now taking part of the stream. Though the initiation of the CubeSat projects in Europe was relatively late, there are nowadays not only CubeSat projects but also many middle-sized small satellites under development. In this paper some exemplary small satellite projects in Europe both CubeSats and middle-sized small satellites are described. Based on the experience of author obtained through a 5-years-long research activity at the University of Stuttgart in Germany, exemplary system architecture of modern middle-sized small satellites is described. Along the European small satellite development activities future key technologies are becoming available, which can be also of Japanese interest. For example, space plug and play avionics products marketed in Europe are possible targets to be introduced to Japanese future small satellites. The aspect that most of the European products are ITAR-free makes them very attractive to communities outside Europe including Japan. On the contrary, Japanese small satellites-related products and technologies will be highly welcomed by the European community. In this sense Europe can be one of the strong partners of Japan as well as a possible customer of Japanese small satellite technologies. The author strongly recommends that Japan actively cooperate with European community to achieve rapid technology development and demonstrations.

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Many universities are now developing CubeSats or micro/nano satellites. Some companies, such as Surrey Satellite Technology Ltd. (SSTL) or Innovative Solutions In Space (ISIS), were spun off from these activities and started the space business. On the other hand, most of space development is operated by government agencies under public funding. The space industry is not acknowledged as a business by the general public. Innovative Nano Satellite Technology Center (INSTEC) was established in April 2010 to make the space industry more active with using a nano satellite. It includes technology development team, mission design team, and universities. One of main missions of this center is to create a new application of nano satellite. Agricultural, piscatorial, environmental, and other mission are under study for coming out five nano satellites launch in next four years.

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Laboratory of Spacecraft Environment Interaction Engineering (LaSEINE) in Kyushu Institute of Technology in researching spacecraft charging and arcing, space debris and small satellite. Laboratory of Spacecraft Environment Interaction Engineering has test facilities specialized space environment and provides the education for the space environment. In particular to spacecraft charging and arcing, the solar array panel made in Japan and abroad were tested. The laboratory is one of the world's leading authorities on spacecraft charging and arcing. Recently, the environment test facilities for a small satellite are developed. These facilities can provide most of test environments required small satellites. In this presentation, our past results and future plan will be reported.

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A non-deterministic analysis method of thin membrane dynamics is presented. The thin membrane is modeled based on the tension field theory, which represents wrinkling phenomenon as a compressive stress relaxation. The generalized α method is applied to formulate a numerical dynamic analysis of wrinkled membrane. A Monte-Carlo approach, where the probability distributions of uncertainties parameters contained in the membrane model are approximated by an ensemble set, is presented to evaluate statistical properties of membrane dynamics behaviors. A simple numerical example is presented to verify the effectiveness of the presented approach.

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This research addresses wrinkle measurement of the square membrane structure under tension loaded at each corner. Wrinkle distribution of a square membrane set in upright position is measured by using laser displacement sensor that is set at a horizontal-vertical stage composed of linear actuators. On the other hand, numerical solution is evaluated through geometrically nonlinear finite element analysis using MITC(Mixed Interpolation of Tensile Components) shell elements. In comparison of numerical results with experimental wrinkle measurement results, the significant factors that give rise to difference between analysis and experiment will be identified to develop a wrinkling analysis model.

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Spatial distribution characteristics of the out of plane displacement of wrinkled membranes were investigated through the statistics analysis of the experimental results of the square wrinkled membranes. The out of plane displacement of wrinkled membranes, held fixed at three corners and subjected to shear loading at remain corner, were treated. The analysis results show that the spatial distribution of the out of plane displacement of the square wrinkled membranes does not follow the normal distribution and log-normal distribution. However, focusing on the average and the standard deviation of the out of plane displacement of the membranes, it turned out that these statistics follow theoretical models such as normal distribution and log-normal distribution.

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Mechanical properties of wrinkles induced by wrapping fold of large space membranes are examined to determine the wrinkle condition in the wrapping fold process. Wrapping fold experiments are performed to investigate the effects of the wrapping tensile force, the crease, and the membrane thickness on the wrinkles. Using the experimental results, the wrinkle condition is examined. To examine the stress around the wrinkles and to confirm the validity of the experimental results, FEM analyses are demonstrated.

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The method for detecting the damage on the plate by using the wavelet transformation is proposed for the first stage to apply the method to the time series vibration data of the large space membrane. The wavelet analysis is applied to the natural vibration mode and transitional response data by FEM, and the deviation of the wavelet coefficients of damaged plate is calculated for detecting the damage. The results indicate that the damage location on the plate is successfully detected by the wavelet coefficients.

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CMES(Centre National D'Etudes Spatiales) and French non-profit organization Planete Scienses have been conducting annual experimental rocket launch campaign called "La Campagne Nationale de Lancement" for the amateur clubs, such as university students and young engineers, since 1960s. The purpose of the rocket launch campaign is not only to make their dream come true but also to teach the participants how the actual development is processed. A student group of Kyushu Institute of Technology has been participated in the French experimental rocket launch campaign since 2006. This paper focuses on the design, development and test results of two rockets called "Ninja-10" and "Sakura" launched in 2010. The first rocket "Ninja-10" performs automatic gliding recovery using parafoil. The rocket tracks the way point gliding, and lands at the target point based on GPS (Global Positioning System) information. The second rocket "Sakura" aims at supersonic flight, which was recovered successfully by using the two-stage parachutes deployment.

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This paper reports space experimental result for the Tethered Space Robot -S (TSR-S) on the sounding rocket "S-520-25." The tethered space robot is a new type of space robot connected to tether. The major advantage of the tethered space robot is that its attitude can be controlled under tether tension by its own link motion. The S-520-25 was launched on August 31, the TSR-S experiment started at 285 seconds after the launch. Tether was extended and kept its tension, and attitude control of the robot was performed.

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Electro Dynamic Tether (EDT) system is one of the non-chemical propulsion systems on low earth orbit (LEO) in the future. The tether technologies rocket experiment (T-REx) mission was proposed, which is the first attempt in the world to employ a bare tape tether. The sounding rocket S520-25 is provided for the T-REx mission. In this mission, the tape tether is stored in a storage box in a foldaway manner, which is a new concept of tether deployment schemes. To expand EDT system feasibility, a small satellite mission of EDT system, following T-Rex mission, is planned, in which a bare tape tether of 3km stored in the folding manner will be deployed. However, shape of the foldaway tape tether storage is concerned to affect the design of the spacecraft in case that the tether length becomes longer, and simple expansion of scale will not be able to cope with this problem. In this paper, in order to improve store efficiency, we expand foldaway manner to the two dimensions, called "cross-shift foldaway storage,"

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A pico-satellite HAYATO (KSAT) was launched on the piggyback of HIIA 17 from Tanegashima Space Center on May 21, 2010, and put into a circular orbit of altitude of 300 km. HAYATO has a 10-cm cube structure and is the first CubeSat onboard a Ku-band transmitter. We had successfully caught telemetry signals with a ground control system at Kagoshima University after eleven days of the satellite launch. Despite of a limited operation period, we have confirmed that most of bus components, such as solar cells, a power control unit, secondary batteries, and onboard computer and a Ku-band transmitter, were survived space environment during eighteen days.

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A Soka University pico-satellite "Negai" measures mere 10cm cube and weights just one kilogram. Its orbit is 300km with inclination of 30 degrees. In 30 days or so after launch it will be dragged by the air and it is burnt out to become a manmade shooting star when reentering to the atmosphere. People believe wishing upon a shooting star makes their dreams come true. The main mission is to carry children's dreams recruited from the public microfilmed to be loaded on the satellite. Hence it is called "Negai" or "Wish." The technical mission is to space prove the high functional information system with inside triple-redundant fault-tolerant soft-core CPU embedded in an FPGA and reliable picture transmission system. This paper emphasized on the technical mission as well as how we operated so short mission life operation with 30 degrees inclination.

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This paper is a continuation of a previous study whereby the planar attitude control of a deputy satellite encircling a central satellite body is discussed. In this extension, however, the inclusion of sensor and actuator noise is made. In reality the sensitivity of both the positional measurement and charge induction system will limit the performance of the satellite formation. Attitude and positional control are achieved by exploiting the spacecraft charges, a Lyapunov based control law, a switching control logic and a temporary guidance ellipse method. The desired attitude is defined as the deputy satellite body fixed y-axis pointing towards the composite satellite centre of mass. In translational terms the target path (nominal reference motion) is a Clohessy Wiltshire bounded solution relative to the central satellite body. The influence of actuator noise into the feedback system is hereby investigated.

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With the increasing use of the International Space Station, humans have more opportunities to work in space. In space, a mobility device that operates efficiently is needed. In this research, a mobility system called the "Tether Space Mobility Device" (TSMD) is proposed. TSMD has a mechanism that enables the tether to move an object. In this study, the TSMD model is composed of two rigid bodies and one flexible body that can express motion with large deformation and large displacement. Several modeling of TSMD is performed. An influence on motion and control of TSMD is discussed.

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This paper proposes an approach to design a rendezvous trajectory for active debris removal. Designing the active debris removal mission, it is preferable to remove multiple debris sequentially in a single mission in terms of cost efficiency. The trajectory design procedure has the following three steps: selecting the removal target debris from many candidates; specifying the removal order; and designing the rendezvous trajectory with a low ΔV. Lambert's problem is applied as the rendezvous motion equation to design the transfer orbit from debris to next target debris. To demonstrate the feasibility of the proposed design procedure, some numerical results using genetic algorithm are shown.

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A parafoil is applicable to an earth-returning vehicle as a promising gliding system. At landing flare is a useful way to brake a parafoil. Height from the ground was appropriate as a timing of flare. Maneuver of flare was automated by H8 microcomputer. Experimental flight system with parafoil was used to verify the proposed timing of flare. As a result, effective height to start a flare was between 3.5[m] to 4.5[m]

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In this report, we describe the outline of the GLIMS equipment equipped with the JEM exposed facility and the development of the equipment as an engineer belonging to the department of mechanical engineering of the university. Especially, we developed the equipment by the cooperation of Department of Science and Department of Engineering in the development of this mission equipment without ordering to the specialty company of the space appliance. We describe how the teacher at the university that is involved in mechanical engineering should be related to development so that Department of Science may cooperate with Department of Engineering.

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The Space Systems Laboratory of Kyushu Institute of Technology has been studying unmanned suborbital winged rocket as a research subject of future fully reusable space transportation system since 2005. The flight tests of a small scaled winged rocket were conducted five times from 2008 to 2009. A larger winged rocket with a hybrid called CAMUI, which will reach to a higher altitude, is under development in collaboration with Hokkaido University, National Defense Academy, JAXA, IHI Aerospace Co. Ltd., and other aerospace industries for validating INS/GPS hybrid navigation system, real time trajectory generation and guidance algorithm using GA implemented on FPGA, H∞ and adaption control theory. This paper reports current design, development and flight test plan of the winged rocket.

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Tohoku University and Hokkaido University started the development of a new 50-kg microsatellite RISING-2 at July 2009. This satellite inherits the development technique of RISING (SPRITE-SAT) launched on January 2009. The progress is shown in this paper. Using a Cassegrain telescope with 10-cm diameter and 1-m focal length, earth surface is observed with 5-m resolution from 700-km-alt sun synchronous orbit. By 3-axis attitude stabilization using reaction wheels and star sensors, the designated area on earth surface can be observed. In addition to color images, multi-spectrum images of cumulonimbus are observed by using a liquid crystal tunable filter. As a secondary mission, transient luminous events such as sprite are observed, which is same mission as SPRITE-SAT.

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Under the current development of mid-to-large size satellites, the high reliability is mandatory to avoid failures and their development cost increases enormously to achieve the high reliability. On the other hand, several universities develop and launch nano-satellites with low cost for the purpose of education from around 2000. To generate new market for satellite utilization, low cost and fast development are key points. The balance of cost and reliability is one of the very important points to realize the markets. The theoretical research toward the balance of cost and reliability is being conducted through the governmental first program "New Space Development and Utilization Paradigm by Nano-satellites Introducing Japan-oriented Reasonable Reliable Systems Engineering". This paper presents the concept of the way to realize the reasonably reliable systems engineering. Current reliability is based on the assumption that there is no miss-design and it only depends on the random failure of parts. However, many of real on-orbit failures were caused by design errors. We propose the new reliability which includes design error and the definition of the reasonably reliable Systems Engineering. The realization concept consists of re-use of design, reduction of complexity, functional redundancy and simple organization to develop nano-satellites.

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Inflatable structure is the thin membrane which is sustained by high pressure gas inside it, and has attracted a lot of attention for the large structure in space. To verify membrane deployment with inflatable tube on orbit, we are developing the nano-satellite named SPROUT (SPace Research On Unique Technology). The volume and electric power which can be used for the inflation system in nano-satellite are severely limited and the gas leak of the tank is also undesirable. So we proposed the small SMA valve with low power consumption which opens the high pressure gas tank on orbit. We conducted demonstration experiments to verify the effectiveness of the small SMA valve. This paper introduces the details of the small SMA valve and reports the results of experiments.

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One-dimensional symmetrical explosive loadings are applied to expand structural components: tubular cylinders, spherical shells and rings of 304 stainless steel and double and single walled cylinders of an aluminum alloy, A5052 to fragmentation, and the effects of wall thicknesses, explosive driver diameters and the constant proportionality of the in-plane biaxial stretching rates are investigated on the deformation and fracture behavior of three types of single walled structures experimentally and numerically. In the cylinder tests, the driver is a column of high explosive PETN, inserted coaxially into the bore of a cylinder and initiated by exploding a fine wire bundle at the column axis using a discharge current. In case of the ring tests, ring specimens are placed onto a cylinder charged with the PETN as an expansion driver, and for sphere tests, a specimen filled with the PETN is also initiated by exploding a fine copper wire line with small length located at the central point.

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In future lunar, planetary or asteroid explorations, in-situ analysis of rock samples are strongly demanded to obtain many data from various aspects. For precise composition analysis, a sample surface should be smoothed. In this report, a surface shaver with a piezoelectric actuator is proposed and its machining performance in air is investigated. Shaving teeth are mounted at the ends of a lever mechanism. The device is pressed through four springs onto the specimen with a linear actuator. When a sinusoidal voltage of 50 Vp-p and an offset voltage of 25 V ware applied, the natural frequency was 556 Hz and the unloaded amplitude of shaving teeth were 0.77 mmp-p. Basalt samples were machined for 10 minutes in air. The surface roughness was small with an increase of the pressing force. However, the removal amount was smaller with an increase of the pressing force further. The surface roughness varied widely not only due to removal amount but also due to pores.

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Exploding Wire-Pulsed Plasma Thruster (EW-PPT) is the satellite thruster using a wire explosion. Wire explosion is the phenomenon that wire is exploded by thermal expansion due to low-voltage pulse current from capacitor bank (charging voltage: about 280V, capacity of condenser: 680-5440μF). The produced expansion gasses after exploding a wire contribute as propulsion of thruster. This study, obtain the velocity of the pendulum to measure impulse bit(I_<bit>). But there is a problem that impulse bit is underestimated because the pendulum's mass is too light. The purpose of this paper is to revaluate impulse bit by increasing the pendulum's mass. As a result, impulse bit (I_<bit>) is 11598μN・sec with the wire of Al. This value is larger than the value measured by using light-pendulum.

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The purpose of this study is to establish a measurement technique of aerodynamic force for the four-winged flapping vehicle which has been developed. The detection of downward force on a flat plate of the downward stream generated by a hovering device is proposed in this study. This indirect-measured force was compared with the direct-measured force. Both measured values showed the good agreement in the thrust measurement of propeller. This method was applied to the four-winged flapping vehicle. The variation of indirect-measured force was smaller. It was confirm that the indirect-measured force rose with the increase of beating frequency.

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"HORYU" a 10cmx10cmx10cm CUBESAT, has been developed by students group of Kyusyu Institute of Technology, Japan. In system engineering, the important element to success is to test well. Not only system test but also level of sub-system and component tests is required. In such a level tests, feasibility, interfaces between subsystem and subsystem, and robustness, are checked. In the system test, working sequence that HORYU will be performed in space will be tested on the ground. The tests consist 3 parts. The first one is initial sequence that HORYU performs after released from the rocket. Also HORYU will be tested normal mode, and mission mode on the ground as well. In the paper, the tests are described in detail.

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Technology demonstration satellite Earth Observatory - the TSUBAME has two main mission: Visible Earth observation; Measurement of polarization of hard X-ray photons from gamma-ray bursts (GRB). Attitude Determination System (ADS) of TSUBAME has the following sensors: Magnetometers (TAMs), Solar Sensors, MEMS gyro, Star Trackers, Fiber Optic Gyro (FOG), GPS receiver. To ensure satellite survival during each mission only several types of sensor will be used in order to minimize power consumption. This paper presents a robust algorithm using TAM and MEMS gyro sensors based on Unscented Kalman Filter (UKF) where both the three-axis attitude and gyro sensor biases are estimated. This algorithm will be used during sun pointing mode because of small power consumption of TAMs and MEMS gyro sensors. Numerical simulation example is given to certify the proposed algorithm and its estimation accuracy.

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Hyper Spectral Camera (HSC) is a VNIR (visible and near-infrared) hyperspectral sensor for micro satellites. The objective of the HSC is to provide high-quality hyperspectral images and to utilize for agricultural area. The HSC acquires GSD (ground sampling distance) of 15m over a swath width of 15km. The spectrometer is equipped with a direct vision prism and covers wavelength range from 450nm to 1000nm. The result of the optical design indicated that high imaging quality at each wavelength is achieved. The HSC also has data handling subsystem. High-general versatility for data handling and interface is implemented to the HSC. The subsystem is integrated by FPGA and uniquely installs mass memory and some peripheral components. Space Wire interfaces the HSC and satellite bus subsystem. It is scheduled to complete the HSC Proto-Flight Model development at the end of FY2010.

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This paper describes a concept of monitoring the debris environment around a certain primary spacecraft by an accompanying micro satellite. Space debris is the collection of objects in orbit around the Earth that is derived from space activities and of no use any more. Space agencies have become more and more susceptible to the debris since it has caused serious damages to operational spacecraft in recent years. Some debris can be observed by optical systems and spacecraft can maneuver to avoid the collisions with them. However, there still exist much small debris in space that cannot be forecasted. Especially, the micro debris, which size is less than 1cm, has become a major threat due to its existing number, the destructive energy, collision probability, and unknown position and velocity. For operational spacecraft, it is a major concern to know the environment around the spacecraft. The micro satellite presented in this paper is designed to detect this micro debris around a primary spacecraft using space debris detector in quasi-real-time, so that the environment and risks in orbit can be better understood based on the measurement. This paper shows the details from the background to the mission analysis.

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The Laboratory for Space Systems (LSS) in Tokyo Institute of Technology is developing a small satellite named "TSUBAME", which has two main missions: observation of polarized gamma-ray high-speed attitude maneuver with the Micro-CMGs, and earth observation with a small optical camera. This paper is focused on the thermal and structural design of its engineering model.

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The variable geometry truss (VGT) is a truss structural system having a number of length-adjustable members. In this study, we make an experiment system of a VGT. We deal with the characteristic of shape-memory alloy (SMA) wires as actuators and mechanical characteristic of a VGT. A heat-temperature relation model of SMA is developed; we formulate the forward kinematic problem of the VGT taking account of the SMA thermo-mechanical behavior. The quasi-static behavior of the VGT is also discussed.

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In this study, we propose a concept of self-thickness-growing panel using shape memory polymer (SMP) as actuators for light-weight structures. The panel as a sandwich structure is made of two facing SMP plates extended using the shape fixation effect, and one elastic thin-plate put inside and attached to the SMP plates at a ruled interval. When the temperature of SMP becomes above its glass transition temperature, the SMP's elastic modulus drastically reduces, but embedded recovery force causes a buckling deformation of the elastic thin-plate, increasing panel's thickness. This paper reports the results of concept verification through experiments and numerical calculations. The effect of secondary-shape forming, which is one of the structural characteristics of SMP, is also discussed for concept's viability.

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A strategy for designing modes of intentional deformations and distribution of surface adjustment mechanisms are developed. The intentional deformations are used for shape control of a reconfigurable antenna system to determine control inputs. Surface deformations of a reflector are corrected by using the surface adjustment mechanisms. Efficiency of each intentional deformation and surface adjustment mechanism is evaluated and useless intentional deformations and useless surface adjustment mechanisms are eliminated on the basis of the evaluated values. Some numerical simulations are carried out to demonstrate the effectiveness of the strategy.

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To meet advanced science missions, large and precise support structures such as truss structures are needed. In this paper, pointing control of a truss structure is discussed. To control the truss structure, thermal expansion of truss members is utilized instead of mechanical actuators. Heaters are equipped to truss members so that the thermal expansion of the members is controlled by heaters. PI control is applied to an experimental model which is box truss with 1.9m height. Through experiments, it is shown that the truss structure can be controlled with good accuracy, for example, within 3 arcsec error.

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JAXA is planning new asteroid exploration mission after "HAYABUSA". This planned mission requires much higher guidance accuracy in approach and touchdown phase than previous mission since it is expected to touchdown inside of the newly made crater. For position controller design Model Predict Control (MPC) which can consider limitations in control input and predict future state is applied in this paper. The performance and usefulness of this control algorithm is evaluated through numerical simulation.

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The minorbody explorer called "HAYABUSA" conducted sampling mission on the minorbody "ITOKAWA", and now it is planning to develop next minorbody explorers. The LSS, laboratory for space systems at the Tokyo Institute of Technology, and JAXA, propose the adhesive based sampling system for next minorbody explorers. By using this sampling system, it becomes possible to get larger size and heavier mass samples compare with the samples which are able to get by HAYABUSA's sampling system. In this paper, Description of the adhesive based sampling system, results of evaluation experiments and analysis of the sampling mechanism are described and discussed.

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It is known that the excavation resistance of the lunar regolith tends to be larger than that of typical terrestrial soils due to the high relative density and angular grain shapes of the lunar regolith. So it is necessary to improve the efficiency of excavation, i.e. to reduce the excavation resistance, because the available energy and the possible size for a lunar excavator will be limited especially in the initial phase of lunar development near future. In this paper, the optimal excavation conditions have been investigated when the rippers are used to loosen the regolith prior to the excavation by a wide blade like a dozer like a dozer blade. It was verified by comparison with excavation on terrestrial sand that the interlocking of grains due to highly angular grains of the lunar regolith makes ripping helpful in excavation energy reduction. Also, the effect of gravel content is studied although that has been ignored in the existing researches about lunar excavation.

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JAXA is carrying out research and development of a lunar lander and its mobile robot (rover) aimed at precursor of human lunar exploration and lunar science. The target areas for lunar exploration are mainly in mountainous zones, and the moon's surface is covered by regolith. Achieving a steady run on such irregular terrain is the big technical problem for rovers. This was determined considering the mass and expected payload of the rover. This paper describes the technical issues of the rover designed for lunar exploration, and presents the trend and status of research and development. This paper also gives study and analysis results about suspension mechanisms of the lunar exploration rover.

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JAXA is developing a mobile rover to lunar surface exploration or base construction as a follow-on KAGUYA. Because the lunar surface is covered by regolith, implying an irregular and rough terrain, the rover has difficulty in mobility. Therefore a new low-pressure wheel is recommended for high mobility performance and low power consumption with a less complex mechanism. A low-pressure wheel can change its contact shape and pressure distribution to account for terrain. In this paper, the procedure for the measurement of mobility parameters like contact pressure on the deformable terrain, and a contact mobility model for low-pressure wheels are presented. This measurement is valuable for analyzing the interaction between a low-pressure wheel and the deformable terrain.

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