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As interest in low-cost reusable launch vehicles and extraterrestrial exploration has increased in recent years, soft-landing techniques have become important. A pintle injector can help realize this because it is capable of thrust control. However, research on this topic is very limited, and general optimization design procedures have not been completely established. In particular, no studies have examined orifice adjustment for annular flow, which is important in thrust control. In this study, a new design concept for a pintle injector is presented specifically to improve spray uniformity in a 400 N class engine; this maintains the concentricity of the pintle rod associated with the radial flow's orifice size. The primary focus here was on spray tests that were conducted to obtain the control range of the orifice area for annular flow. Spray characteristics such as spray angle, spray uniformity, and droplet size were analyzed, from which empirical correlations were derived. Finally, the optimum control range for the annular flow's orifice area was estimated from the perspective of atomization performance. This can be of reference to develop an enhanced thrust control system. • New design concept for a pintle injector was introduced to improve uniformity in a 400 N class liquid rocket engine. • Spray tests helped find the control range of the annular flow's orifice area. • An appropriate correlation equation was developed for the parameters. • The control range was estimated using empirical correlations with respect to the degree of atomization. • A database for linear control system design was established. [ABSTRACT FROM AUTHOR]

Abstract Previous and current Mars rover missions have noted a nearly ubiquitous presence of duricrusts on the planet surface. Duricrusts are thin, brittle layers of cemented regolith that cover the underlying terrain. In some cases, the duricrust hides safe or relatively safe underneath the top soil. However, as was observed by both Mars exploration rovers, Spirit and Opportunity, such crusts can also hide loose, untrafficable terrain, leading to Spirit becoming permanently incapacitated in 2009. Whilst several reports of the Martian surface have indicated the presence of duricrusts, none have been able to provide details on the physical properties of the material, which may indicate the level of safe traversability of duricrust terrains. This paper presents the findings of testing terrestrially-created duricrusts with simulated Martian soil properties, in order to determine the properties of such duricrusts and to discover what level of hazard that they may represent (e.g. can vehicles traverse the duricrust surface without penetration to lower sub-surface soils?). Combinations of elements that have been observed in the Martian soil were used as the basis for forming the laboratory-created duricrusts. Variations in duricrust thickness, water content, and the iron oxide compound were investigated. As was observed throughout the testing process, duricrusts behave in a rather brittle fashion and are easily destroyed by low surface pressures. This indicates that duricrusts are not safe for traversing and they present a definite hazard for travelling on the Martian landscape when utilising only visual terrain classification, as the surface appearance is not necessarily representative of what may be lying beneath. Highlights • Fabrication of artificial Mars duricrusts based on Mars geology. • Empirical testing and evaluation of artificial duricrust mechanical properties. • Testing of safe rover trafficability using standard geotechnical site survey methods. • Useful for full sensor testing (e.g. Ground Penetrating Radar, soil sampling systems) or as a physical analogue only (e.g. rover sinkage experiments). [ABSTRACT FROM AUTHOR]

For lunar surface exploration, a deployment system is necessary to allow a rover to leave the lander. The system should be as lightweight as possible and stored retracted when launched. In this paper, two types of retractable deployment systems for lunar landing missions, telescopic- and fold-type ramps, are discussed. In the telescopic-type system, a ramp is stored with the sections overlapping and slides out during deployment. In the fold-type system, it is stored folded and unfolds for the deployment. For the development of these ramps, a design concept study and structural analysis were conducted first. Subsequently, ramp deployment and rover release tests were performed using the developed ramp prototypes. Through these tests, the validity of their design concepts and functions have been confirmed. In the rover release test, it was observed that the developed lightweight ramp was sufficiently strong for a 50-kg rover to descend. This result suggests that this ramp system is suitable for the deployment of a 300-kg-class rover on the Moon, where the gravity is about one-sixth that on Earth. The lightweight and sturdy ramp developed in this study will contribute to both safe rover deployment and increase of lander/rover payload. [ABSTRACT FROM AUTHOR]

Chinese first Mars exploration activity, orbiting landing and roaming collaborative mission, has been programmed and started. As a key technology, Mars lander guidance system is intended to serve atmospheric entry, descent and landing (EDL) phases. This paper is to report the formation process of enabling technology road map for Chinese Mars lander guidance system. First, two scenarios of the first-stage of the Chinese Mars exploration project are disclosed in detail. Second, mission challenges and engineering needs of EDL guidance, navigation, and control (GNC) are presented systematically for Chinese Mars exploration program. Third, some useful related technologies developed in China's current aerospace projects are pertinently summarized, especially on entry guidance, parachute descent, autonomous hazard avoidance and safe landing. Finally, an enabling technology road map of Chinese Mars lander guidance is given through technological inheriting and improving. [ABSTRACT FROM AUTHOR]

Drilling and coring, as an effective way to acquire lunar regolith along the depth, is widely used in the field of planetary explorations. Because there is no relative sliding between the lunar regolith and the flexible tube, using the flexible tube coring method can acquire high recovery rate and keep the stratification of regolith samples. Very little work has been done to analyze the flexible tube coring process. A proper understanding of the coring process is necessary to develop the drilling strategy and verify whether the designed drill tool is appropriate. In this paper, two models are developed to analyze stress distribution in lunar regolith simulant during coring. Based on the developed models, a prediction method of recovery rate is developed to analyze the influence of the drilling parameters on the recovery rate. Comparison of the model calculation results with data of drilling and coring experiments demonstrated that the model based on the Terzaghi bearing theory can effectively predict the tendency when the recovery rate begins to decrease. [ABSTRACT FROM AUTHOR]

Landing safety is the prior concern in planetary exploration missions. With the development of precise landing technology, future missions require vehicles to land on places of great scientific interest which are usually surrounded by rocks and craters. In order to perform a safe landing, the vehicle should be capable of detecting hazards, estimating its fuel consumption as well as touchdown performance, and locating a safe spot to land. The landing site selection process can be treated as an optimization problem which, however, cannot be efficiently solved through traditional optimization methods due to its complexity. Hence, the paper proposes a synthetic landing area assessment criterion, safety index, as a solution of the problem, which selects the best landing site by assessing terrain safety, fuel consumption and touchdown performance during descent. The computation effort is cut down after reducing the selection scope and the optimal landing site is found through a quick one-dimensional search. A typical example based on the Mars Science Laboratory mission is simulated to demonstrate the capability of the method. It is proved that the proposed strategy manages to pick out a safe landing site for the mission effectively. The safety index can be applied in various planetary descent phases and provides reference for future mission designs. [ABSTRACT FROM AUTHOR]

We tested science operations strategies developed for use in remote mobile spacecraft missions, to determine whether reconnoitering a site of potential habitability prior to in-depth study (a walkabout-first strategy) can be a more efficient use of time and resources than the linear approach commonly used by planetary rover missions. Two field teams studied a sedimentary sequence in Utah to assess habitability potential. At each site one team commanded a human “rover" to execute observations and conducted data analysis and made follow-on decisions based solely on those observations. Another team followed the same traverse using traditional terrestrial field methods, and the results of the two teams were compared. Test results indicate that for a mission with goals similar to our field case, the walkabout-first strategy may save time and other mission resources, while improving science return. The approach enabled more informed choices and higher team confidence in choosing where to spend time and other consumable resources. The walkabout strategy may prove most efficient when many close sites must be triaged to a smaller subset for detailed study or sampling. This situation would arise when mission goals include finding, identifying, characterizing or sampling a specific material, feature or type of environment within a certain area. [ABSTRACT FROM AUTHOR]

Planetary surface exploration technology over the past few years has seen significant advancements on multiple fronts. Robotic exploration platforms are becoming more sophisticated and capable of embarking on more challenging missions. More unconventional designs, particularly transforming architectures that have multiple modes of locomotion, are being studied. This work explores the capabilities of one such novel transforming rover called the Transforming Roving-Rolling Explorer (TRREx) . Biologically inspired by the armadillo and the golden-wheel spider, the TRREx has two modes of locomotion: it can traverse on six wheels like a conventional rover on benign terrain, but can transform into a sphere when necessary to negotiate steep rugged slopes. The ability to self-propel in the spherical configuration, even in the absence of a negative gradient, increases the TRREx's versatility and its concept value. This paper describes construction and testing of a prototype cylindrical TRREx that demonstrates that “actuated rolling” can be achieved, and also presents a dynamic model of this prototype version of the TRREx that can be used to investigate the feasibility and value of such self-propelled locomotion. Finally, we present results that validate our dynamic model by comparing results from computer simulations made using the dynamic model to experimental results acquired from test runs using the prototype. [ABSTRACT FROM AUTHOR]

The Japan Aerospace Exploration Agency launched the asteroid sample return spacecraft “Hayabusa2” on December 3, 2014. Hayabusa2 will reach the C-type asteroid 1999 JU3 in 2018, and return back to the Earth in 2020. Sample collections from three sites, four surface rovers deployment and a 4 MJ-class kinetic impact crater generation are planned in the 1.5 years of the asteroid-proximity operation. The mission objective of Hayabusa2 has three aspects, science, engineering and exploration, all of which would be expanded by the successful round-trip journey. This paper describes the outline of the Hayabusa2 mission and the current flight status after the seven month of the interplanetary cruise. [ABSTRACT FROM AUTHOR]

A novel concept for Chinese Chang'e-4 lunar exploration mission is presented in this paper at first. After the success of Chang'e-3, its backup probe, Chang'e-4 lander/rover combination, would be upgraded and land on the unexplored lunar farside by the aid of a relay satellite near the second Earth-Moon Lagrange point. Mineralogical and geochemical surveys on the farside to study the formation and evolution of lunar crust and observations at low radio frequencies to track the signals of the Universe's Dark Ages are priorities. Follow-up Chinese lunar exploration activities before 2030 are envisioned as building a robotic lunar science station by three to five missions. Finally several methods of international cooperation are proposed. [ABSTRACT FROM AUTHOR]

The atmospheric re‐entry domain is a cornerstone of a wide range of space applications, ranging from reusable launcher stages developments, robotic planetary exploration, human space flight, to innovative applications such as reusable research platforms for in orbit validation of multiple space applications technologies. The Intermediate experimental Vehicle (IXV) is an advanced demonstrator which has performed in-flight experimentation of atmospheric re-entry enabling systems and technologies aspects, with significant advancements on Europe's previous flight experiences, consolidating Europe's autonomous position in the strategic field of atmospheric re-entry. The IXV mission objectives were the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled reentry system, integrating critical re-entry technologies at system level. Among such critical technologies of interest, special attention was paid to aerodynamic and aerothermodynamics experimentation, including advanced instrumentation for aerothermodynamics phenomena investigations, thermal protections and hot-structures, guidance, navigation and flight control through combined jets and aerodynamic surfaces (i.e. flaps), in particular focusing on the technologies integration at system level for flight, successfully performed on February 11th, 2015. [ABSTRACT FROM AUTHOR]

Planetary exploration has been carried out with solitary probes since the nineteen-sixties; on the other hand, the newly emerging paradigm for robotic exploration shows multi-expertize, complex modular systems as necessary for efficient and thorough activities. In this paper we propose a modular Cable Driven Parallel Robot (CDPR) that is deployed by a rover, which can take advantage of its large workspace for tasks as inspection or light manipulation. While the general deployment procedure is described, focus is given on the CDPR; a model for the pseudostatics of the robot is formulated, as well as an analysis on its modules stability. The workspace is then characterized using appropriate metrics. Results show that a 1 Kg payload for the end-effector is effectively feasible with substantial margin for an equilateral triangular workspace of 10 m side. Finally, several possible practical applications are illustrated. [ABSTRACT FROM AUTHOR]

A static rock splitter device based on high-force, high-temperature shape memory alloys (HTSMAs) was developed for space related applications requiring controlled geologic excavation in planetary bodies such as the moon, Mars, and near-Earth asteroids. The device, hereafter referred to as the shape memory alloy rock splitter (SMARS), consisted of active (expanding) elements made of Ni 50.3 Ti 29.7 Hf 20 (at%) that generate extremely large forces in response to thermal input. The pre-shaping (training) of these elements was accomplished using isothermal, isobaric and cyclic training methods, which resulted in active components capable of generating stresses in excess of 1.5 GPa. The corresponding strains (or displacements) were also evaluated and were found to be 2–3%, essential to rock fracturing and/or splitting when placed in a borehole. SMARS performance was evaluated using a testbed consisting of a temperature controller, custom heaters and heater holders, and an enclosure for rock placement and breakage. The SMARS system was evaluated using various rock types including igneous rocks (e.g., basalt, quartz, granite) and sedimentary rocks (e.g., sandstone, limestone). [ABSTRACT FROM AUTHOR]

Special percussive mechanisms, e.g. Auto Gopher and UltraSonic/Sonic Driller/Corer (USDC) have been developed by NASA Jet Propulsion Laboratory and Honeybee Robotics Spacecraft Mechanisms, Corp. to address some of the limitations of current drilling techniques for planetary exploration. The percussive mechanism consists of an ultrasonic horn, a free mass (hammer) and the drill rod. This paper presents the analysis of the interaction between these three components. The impact between the components (i.e. ultrasonic horn and free mass, and free mass and drill rod) is analyzed using solid body collision analysis applying the principle of conservation of momentum. The drill rod is modeled for both undamped and damped cases with equivalent generalized single degree of freedom system. Various values are used for the coefficient of restitution to account for energy loss during impact. The energy transferred to the drill rod by the free mass is obtained determining the change in kinetic energy due to impact. It is observed that the free mass converts the high frequency of oscillation of the ultrasonic horn into lower frequency impacts on the drill rod. A decrease in the coefficient of restitution results in a decrease in the number of impacts, impulse imparted to the drill rod and energy transferred to the drill rod by the impact of the free mass. [ABSTRACT FROM AUTHOR]

Astrobiology is a multidisciplinary field of research, which encompasses scientists ranging from cosmology, astronomy, planetary sciences, physics, chemistry, geology, paleontology to biology. In order to map the existing astrobiological expertise in Europe a comprehensive community consultation has been performed within the AstRoMap (Astrobiology Road Mapping) project that is supported by the European Commission FP7 framework. From this information a data base of scientists (European and beyond) interested in astrobiology and planetary exploration (see: http://www.astromap.eu/database.html ) has been established. It reflects the demography and research and teaching activities of the astrobiology community, as well as their professional profiles and involvement in astrobiology projects. The database provides an ideal platform for networking between scientists interested in the various fields of astrobiology. Considering future aspects of astrobiology in Europe, the need for more astrobiology-dedicated funding programs at the EU level, especially for cross-disciplinary groups, was stressed. This might eventually lead to the creation of a European laboratory of Astrobiology, or even of a European Astrobiology Institute. [ABSTRACT FROM AUTHOR]

Asteroids and comets have collided with the Earth in the past and will do so again in the future. Throughout Earth׳s history these collisions have played a significant role in shaping Earth׳s biological and geological histories. The planetary defense community has been examining a variety of options for mitigating the impact threat of asteroids and comets that approach or cross Earth׳s orbit, known as near-Earth objects (NEOs). This paper discusses the preliminary study results of selecting small (100-m class) NEO targets and mission analysis and design trade-offs for validating the effectiveness of a Hypervelocity Asteroid Intercept Vehicle (HAIV) concept, currently being investigated for a NIAC (NASA Advanced Innovative Concepts) Phase 2 study. In particular this paper will focus on the mission analysis and design for single spacecraft direct impact trajectories, as well as several mission types that enable a secondary rendezvous spacecraft to observe the HAIV impact and evaluate it׳s effectiveness. [ABSTRACT FROM AUTHOR]

This paper discusses a landing response control system based on the momentum exchange principle for planetary exploration spacecraft. In the past, landing gear systems with cantilever designs that incorporate honeycomb materials to dissipate shock energy through plastic deformation have been used, but once tested before launch, the system cannot be used in a real mission. The sky crane system used for the Mars Science Laboratory by NASA can achieve a safe and precise landing, but it is highly complex. This paper introduces a momentum exchange impact damper (MEID) that absorbs the controlled object׳s momentum with extra masses called damper masses. The MEID is reusable, which makes it easy to ensure the landing gear׳s reliability. In this system, only passive elements such as springs are needed. A single-axis (SA) model has already been used to verify the effectiveness of MEIDs through simulations and experiments measuring the rebound height of the spacecraft. However, the SA model cannot address the rotational motion and tipping of the spacecraft. This paper presents a two-landing-gear-system (TLGS) model in which multiple MEIDs are equipped for two-dimensional analysis. Unlike in the authors׳ previous studies, in this study each MEID is launched when the corresponding landing gear lands and the MEIDs do not contain active actuators. This mechanism can be used to realize advanced control specifications, and it is simply compared with previous mechanisms including actuators, in which all of the MEIDs are launched simultaneously. If each MEID works when the corresponding gear lands, the rebound height of each gear can be minimized, and tipping can be prevented, as demonstrated by the results of our simulations. [ABSTRACT FROM AUTHOR]

In this study, we propose a new attitude determination system, which we call Irradiance-based Attitude Determination (IRAD). IRAD employs the characteristics and geometry of solar panels. First, the sun vector is estimated using data from solar panels including current, voltage, temperature, and the normal vectors of each solar panel. Because these values are obtained using internal sensors, it is easy for rovers to provide redundancy for IRAD. The normal vectors are used to apply to various shapes of rovers. Second, using the gravity vector obtained from an accelerometer, the attitude of a rover is estimated using a three-axis attitude determination method. The effectiveness of IRAD is verified through numerical simulations and experiments that show IRAD can estimate all the attitude angles (roll, pitch, and yaw) within a few degrees of accuracy, which is adequate for planetary explorations. [ABSTRACT FROM AUTHOR]

The Japan Aerospace Exploration Agency (JAXA) views the lunar lander SELENE-2 as the successor to the SELENE mission. In this presentation, the mission objectives of SELENE-2 are shown together with the present design status of the spacecraft. JAXA launched the Kaguya (SELENE) lunar orbiter in September 2007, and the spacecraft observed the Moon and a couple of small satellites using 15 instruments. As the next step in lunar exploration, the lunar lander SELENE-2 is being considered. SELENE-2 will land on the lunar surface and perform in-situ scientific observations, environmental investigations, and research for future lunar utilization including human activity. At the same time, it will demonstrate key technologies for lunar and planetary exploration such as precise and safe landing, surface mobility, and overnight survival. The lander will carry laser altimeters, image sensors, and landing radars for precise and safe landing. Landing legs and a precisely controlled propulsion system will also be developed. A rover is being designed to be able to travel over a wide area and observe featured terrain using scientific instruments. Since some of the instruments require long-term observation on the lunar surface, technology for night survival over more than 2 weeks needs to be considered. The SELENE-2 technologies are expected to be one of the stepping stones towards future Japanese human activities on the moon and to expand the possibilities for deep space science. [ABSTRACT FROM AUTHOR]

Abstract: Over the past year we have celebrated the 50th anniversary of planetary exploration, which started with the Venus flyby of Mariner-2; and the 35th anniversary of the Pioneer-Venus multi-probe mission where one large and three small probes descended to the surface of Venus, encountering extreme environmental conditions. At the surface of Venus the temperature is about 460°C, and the pressure is 92bar, with a highly corrosive super-critical CO2 atmosphere. At a Venusian altitude of 50km the pressure and temperature conditions are near Earth-like, but the clouds carry sulfuric acid droplets. Deep probe missions to Jupiter and Saturn, targeting the 100bar pressure depth encounter similar pressure and temperature conditions as the Pioneer-Venus probes did. Mitigating these environments is highly challenging and requires special considerations for designs and materials. While assessing such space mission concepts, we have found that there is an overlap between the extreme environments in planetary atmospheres and the environments experienced by deep-sea explorers back on Earth. Consequently, the mitigation approaches could be also similar between planetary probes and diver watches. For example, both need to tolerate about 100bar of pressure—although high temperatures are not factors on Earth. Mitigating these environments, the potential materials are: titanium for the probe and the watch housing; sapphire for the window and glass; resin impregnated woven carbon fiber for the aeroshell׳s thermal protection system and for the face of the watch; and nylon ribbon for the parachute and for the watch band. Planetary probes also utilize precision watches; thus there is yet another crosscutting functionality with diver watches. Our team, from the Innovation Design Engineering Program of the Royal College of Art, has designed and built a concept watch to commemorate these historical events, while highlighting advances in manufacturing processes over the past three to five decades, relevant to both future planetary mission designs and can be used to produce deep diver watches. In this paper we describe our design considerations; give a brief overview of the extreme environments these components would experience on both Venus and Earth; the manufacturing techniques and materials we used to build the Venus Watch; and its outreach potential to bring a distant concept of planetary exploration closer to Earth. We will also address lessons learned from this project and new ideas forward, for the next generation of this concept design. [Copyright &y& Elsevier]

Abstract: The paper deals with the dynamic modeling of wheeled planetary rovers operating on rough terrain. The dedicated model here presented, although kept as simple as possible, includes the effect of nonlinearities and models the suspensions in a realistic, albeit simplified, way. It can be interfaced with a model of the control system so that different control strategies can be studied in detail and, in case of teleoperated rovers, it can be used as a simulator for training the operators. Different implementations, with different degrees of complexity, are presented and compared with each other so that the user can simulate the dynamics of the rover making a tradeoff between simulation accuracy and computer time. The model allows to study the effects of the terrain characteristics, of the ground irregularities and the operating speed on the behavior of the rover. Some examples dealing with rovers with different configurations conclude the paper. [Copyright &y& Elsevier]

Abstract: The paper deals with the aerodynamic analysis of a manned braking system entering the Mars atmosphere, with the aim to support planetary entry system design studies. The capsule configuration is an axisymmetric blunt body close to the Apollo capsule. Several fully three-dimensional Computational Fluid Dynamics analyses have been performed to assess the flowfield environment around the vehicle to address the aerodynamic performance of the entry capsule within mission exploration to Mars. To this end, a wide range of flow conditions including reacting and non-reacting flow, different angles of attack, and Mach numbers have been investigated and compared. Moreover, non-equilibrium effects on the flowfield around the capsule have been also investigated. Results show that real-gas effects, for all the angles of attach considered, increase both the aerodynamic drag and pitching moment, whereas the lift is only slighted affected. Finally, comparison of the results highlights that experimental and CFD aerodynamic findings available for the Apollo capsule in air adequately represent the static coefficients of the capsule in the Mars atmosphere. [Copyright &y& Elsevier]

Abstract: For missions to Mars, a drilling system is an essential tool in the search for organic matter and simple microbial life. The subsurface layer, which has been protected from radiation, weathering, and oxidation, provides a promising environment that must be investigated comprehensively for biological activity. A drill allows direct access to the subsurface layer for taking measurements and sampling for organic chemistry studies. However, extraterrestrial drilling operations pose numerous challenges: semi-autonomous nature of the drilling process, extreme conditions, and the lack of knowledge of the target’s characteristics. Rigorous testing, evaluation, and procedural development are required to ensure the success of an extraterrestrial drilling mission. In this paper, we review the procedures and results from the preliminary tests of a Mars drill for the Northern Light mission. The prototype model, developed by Dr. T.C. Ngnow with the help of Hong Kong’s Polytechnics University, has a design goal of 2W and 300g. It was delivered to York University in April, 2009, for preliminary functional tests. This paper presents the results from those tests with detailed description of the test procedure. [Copyright &y& Elsevier]

Abstract: In 2005, the Huygens probe, designed by Thales Alenia Space, France, successfully completed its entry and descent in Titan''s atmosphere. In the frame of the Aurora Exploration Program, ESA has initiated industrial studies for the ExoMars mission. The Thales Alenia Space France-led consortium was awarded the contract for the design, development and manufacturing of the Entry and Descent System under Thales Alenia Space—Italy mission prime. Huygens and ExoMars constitute major European milestones in the field of atmospheric entry and descent. Eight out of the ten bodies larger than Mercury in the Solar System have a significant atmosphere to descent in, either to reach a solid surface, or to explore the atmosphere itself. The gained experience in Entry Descent and Landing design will enhance European industry capability to contribute to future planetary exploration missions. This paper assesses the different environments and conditions that Entry Descent and Landing Systems will meet. It discusses how Europe''s Huygens and ExoMars experience will apply in such environments and identifies the critical technologies needed to complement it. It concludes on the elements of a roadmap for the related technological development. [Copyright &y& Elsevier]

Abstract: In late 2006, NASA''s Constellation Program sponsored a study to examine the feasibility of sending a piloted Orion spacecraft to a near-Earth object. NEOs are asteroids or comets that have perihelion distances less than or equal to 1.3 astronomical units, and can have orbits that cross that of the Earth. Therefore, the most suitable targets for the Orion Crew Exploration Vehicle (CEV) are those NEOs in heliocentric orbits similar to Earth''s (i.e. low inclination and low eccentricity). One of the significant advantages of this type of mission is that it strengthens and validates the foundational infrastructure of the United States Space Exploration Policy and is highly complementary to NASA''s planned lunar sortie and outpost missions circa 2020. A human expedition to a NEO would not only underline the broad utility of the Orion CEV and Ares launch systems, but would also be the first human expedition to an interplanetary body beyond the Earth–Moon system. These deep space operations will present unique challenges not present in lunar missions for the onboard crew, spacecraft systems, and mission control team. Executing several piloted NEO missions will enable NASA to gain crucial deep space operational experience, which will be necessary prerequisites for the eventual human missions to Mars. Our NEO team will present and discuss the following: [•] new mission trajectories and concepts; [•] operational command and control considerations; [•] expected science, operational, resource utilization, and impact mitigation returns; and [•] continued exploration momentum and future Mars exploration benefits. [Copyright &y& Elsevier]

Abstract: Robotic landers serve vital reconnaissance roles in the exploration of planetary surfaces, but are constrained by deliverable payload size and environment survivability. Although the Mars exploration rovers (MER) have shown incredible survivability, their solar power source limits the science output per sol. Future landers will be larger, and will incorporate more sophisticated data-collection and analysis packages, which will likely bring with them an increased demand for power. Anticipating this demand, we propose an innovative hybrid power system combining a primary radioisotope thermoelectric generator (RTG) with a secondary alkaline fuel cell. This combination provides the opportunity to utilize more effectively the energy produced by the RTG, to produce and store O2 and H2 via electrolysis of melted ice, and use this obtained O2 and H2 in a variety of ways, including as fuel for a regenerative fuel cell. This hybrid system has applications ranging from planetary rovers and deep-space probes to human habitats. [Copyright &y& Elsevier]

Abstract: Traditionally, space systems have been built for fixed requirements and optimized for highest performance. Future systems for human exploration of Moon and Mars, however, require focus on new architectural strategies geared towards increased affordability and survivability in addition to performance. Reconfigurability is a new paradigm in system design that enhances these qualities. Reconfigurable systems can attain different states with new or modified capabilities, as required with changing needs, over time. Such systems can lower mission costs through mass savings by efficient use of a fixed set of hardware for multiple functions. Their survivability is improved through their ability to reconfigure into different states so that some level of over-all functionality is retained. This study, with a focus on planetary surface vehicles, presents a methodology for determining optimal designs of reconfigurable systems. It also proposes metrics for assessing the impact of reconfigurability. It is found that for the specific scenario considered, the mass utilization efficiency in a fleet of reconfigurable vehicles is increased by 27% while the survivability can be increased by a factor of 3. [Copyright &y& Elsevier]

Abstract: The Spherical Mobile Investigator for Planetary Surface (SMIPS) concept aims at making use of the latest developments within extreme miniaturization of space systems. The introduction of Microelectromechanical Systems (MEMSs) and higher level Multifunctional MicroSystems (MMSs) design solutions gives the robot high performance per weight unit. The untraditional spherical shape makes it easily maneuverable and thus provides a platform for scientific investigations of interplanetary bodies. Preliminary investigations of the SMIPS concept show several advantages over conventional robots and rovers in maneuverability, coverage, size, and mass. A locomotion proof-of-concept has been studied together with a new distributed on-board data system configuration. This paper discusses theoretical robot analysis, an overall concept, possible science, enabling technologies, and how to perform scientific investigations. A preliminary design of an inflatable multifunctional shell is proposed. [Copyright &y& Elsevier]