New Formation Flying Testbed for Analyzing Distributed Estimation and Control Architectures

Future NASA long duration missions will require high performance, reliable, long lived mechanical moving systems. In order to develop these systems, high technology components, such as bearings, gears, seals, lubricants, etc., will need to be utilized. There has been concern in the NASA community that the current technology level in these mechanical component/tribology areas may not be adequate to meet the goals of long duration NASA mission such as Space Exploration Initiative (SEI). To resolve this concern, NASA-Lewis sent a questionnaire to government and industry workers (who have been involved in space mechanism research, design, and implementation) to ask their opinion if the current space mechanisms technology (mechanical components/tribology) is adequate to meet future NASA Mission needs and goals. In addition, a working group consisting of members from each NASA Center, DoD, and DOE was established to study the technology status. The results of the survey and conclusions of the working group are summarized.

Modelling approaches for an ultrasonic percussion drill

The Astrophysics Data Facility at NASA Goddard Space Flight Center supports the processing, management, and dissemination of data obtained by past, current, and future NASA and international astrophysics missions, and promotes the effective use of those data by the astrophysics community, educators, and the public. Our Multiwavelength Milky Way poster was printed for broad distribution. It depicts the Galaxy at radio, infrared, optical, X-ray, and gamma-ray wavelengths. In particular, the poster contains images of the Galactic 21-cm and CO (J = 1 → 0) line emission, and IRAS 12, 60, and 100 μm, COBE/DIRBE 1.25, 2.2, and 3.5 μm, Digitized Sky Survey optical wavelength, ROSAT/PSPC 0.25, 0.75, and 1.5 keV X-ray, and CGRO/EGRET E > 100 MeV gamma ray broadband emission. All of the data sets are publicly available. Captions describe the Milky Way and what can be learned about the Galaxy from measurements made in each segment of the electromagnetic spectrum. The poster is intended to be an educational tool, one that will stimulate heightened awareness by laypersons of NASA's contribution to modern astronomy.Through an interface available on the World Wide Web at http://adf.gsfc.nasa.gov/adf/adf.html one may view the images that appear on the poster, read the poster captions, and locate the archived data and references.

The potential of spaceborne lidar to monitor aerosol layering and mixing with high vertical resolution is reviewed. An overview is presented on aerosol lidar techniques of past, present, and future NASA and ESA lidar missions. The potential of a standard backscatter lidar (LITE, 1994), a backscatter/polarization lidar (CALIPSO, since 2006), a polarization High Spectral Resolution Lidar (HSRL, ATLID, EARTHCARE), and of a multiwavelength polarization HSRL are discussed regarding their ability to derive height profiles of optical and microphysical properties of aerosols and to resolve aerosol types and mixtures as a function of height. The important role of ground-truth activities is emphasized. Measurement examples taken with ground-based lidars illustrate that these systems provide a detailed characterization of complex aerosol scenarios in contrast to the snapshot-like observations with spaceborne lidars.

Amateur astronomy of the Solar System is living a golden age with major contributions to modern planetary science. These contributions cover a wide spectrum of topics that range from the discovery of impacts in Jupiter [1-2], to the observation of stellar occultations by minor bodies [3-4], the characterization of unexpected high-atmospheric events in Mars [5], or the characterization of giant storms on Jupiter [6] and Saturn [7-8]. Besides these examples of high-profile publications, there is an increasing number of amateur contributions to dozens of studies of planetary atmospheres and countless contributions to the study of minor bodies. While we focus here in the role of amateur astronomy observations of planetary atmospheres, we also recognize the varied and healthy professional and amateur collaborations in other areas of solar system astronomy.The reasons behind this golden age lie in the two sides of the collaboration: On the side of amateur astronomers, many of them use very efficient detectors and advanced software tools, and they are highly connected at an international level. Thus, they provide high-quality observations on a regular basis to professional astronomers, or have strong analysis teams like the JUPOS team as an example (http://jupos.privat.t-online.de/index.htm). These frequent amateur observations provide essential monitoring of the temporal evolution of planetary atmospheres. On the other side, professional astronomers are aware of the potential of these observations and actively seek the collaboration of amateur astronomers and citizen scientists. A key case in this regard is NASA’s Juno mission to the giant planet Jupiter, and its large-scale collaboration around the JunoCam instrument on the mission Juno website: https://www.missionjuno.swri.edu/. The mission has been recently extended until 2025 and details of the contribution of amateur observers to this new mission scenario are presented by Orton et al. in session ODAA5 in this meeting. Other examples of professionals seeking a global collaboration with amateurs are the various professional and amateur astronomy services and workshops organized by research projects like the Europlanet 2020 Research Infrastructure (2016-2019) and Europlanet 2024 Research Infrastructure (2020-2024).We anticipate that the trend of amateur astronomy playing an important role in providing additional data sets to space missions will continue to grow and we advocate for the early establishment of such collaborations.  We review some of the elements that have made the collaboration of amateur astronomers with the Juno mission so fruitful for both parties and how this collaboration has grown beyond Jupiter into enhanced collaborations in other fields through networking amateur astronomers and providing a successful example to other fields.We also discuss future ground-based high-resolution amateur observations of Solar System planets in support of future missions. These include the James Webb Space Telescope observations of planets (launch in October 2021), ESA’s Jupiter Icy moons Explorer (JUICE, launching in 2022) and NASA’s Europa Clipper missions to the Jupiter system in the early 2030s, the in situ exploration of Saturn’s moon Titan by the Dragonfly mission (NASA) in 2034, the Envision mission to Venus (if selected by ESA), and possible future missions to the Icy Giants Uranus and Neptune. Each of these ambitious missions will benefit from the strong partnership between amateur and professional planetary scientists. The first in this line is the JWST observations of Giant planets to be conducted in 2022 (see Fletcher et al. in session OPS3 in this conference).Finally, we also show some professional and amateur networking elements developed under the umbrella of the Europlanet projects, including the recently launched Europlanet Telescope Network (https://bit.ly/2Br5LDt), and we present possible scenarios for future pro-am collaborations beyond the end of the Europlanet 2024 project. AcknowledgementsPart of this research has been supported by Europlanet 2024 RI. Europlanet 2024 RI has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 871149.

The capabilities of maximising standard payload modules’ functionalities for applications such as on-orbit satellite servicing or planetary exploration depend critically on the creation and availability of a standard interface (IF). Standard interface should provide, aside from the necessary mechanical interconnections, electrical power and data connections, as well as thermal transfer between “building block” payload modules. The overall flexibility enabled by such IF will allow endless reconfigurations of payload and other modules for different functional requirements. This can be considered a game changer technology, enabling transformation from the current approach to space missions, deploying single-use system with pre-planned and limited functionalities, to a radically new approach with multi-use, dynamically reconfigurable and multi-functional systems. Hence, SIROM aims to set a new research agenda for future affordable space missions. Within this context, the partners of the SIROM (Standard Interface for Robotic Manipulation of payloads in future space missions) project are developing the first standard IF solution that combines the four required functionalities in an integrated and compact form for future space missions. With a mass lower than 1.5 kg and having an external diameter of 120 mm and a height of 30 mm, this novel interface permits not only mechanical coupling but also electrical, data and thermal connectivity between so called Active Payload Modules (APMs), as well as other modules such as the robotic end-effectors. This multi-functional IF features an androgynous design to allow for replacement and reconfiguration of the individual modules in any combination desired. It consists of the following sub-assemblies: mechanical IF, electrical IF, data IF, thermal IF and IF controller. A clear advantage of SIROM design is that its mechanical IF consists of a latching and guiding systems for misalignment correction, capable of withstanding certain robotic arm positioning inaccuracies: ± 5 mm translation and ± 1.5° rotation in all axes. Regarding the electrical and data IFs, SIROM transfers up to 150 W electrical power and provides a data transfer rate of 100 Mbit/s via SpaceWire, plus command communication with speeds up to 1Mbit/s via CAN bus. The thermal IF provides fluidic ports for flow transfer and has the potential to transfer 2500 W between APMs accordingly provided with the corresponding close-loop heat exchange system. Although not envisaged for SIROM current design, a possible variation could be to use these ports for satellite re-fuelling. Apart from that, SIROM exhibits redundant coupling capabilities: it can match and couple another completely passive SIROM. It is provided with main and redundant connectors for thermal, electrical, data and control flow in case of one of the lines fails. All in all, SIROM will enable long duration missions with no logistic support, refurbishing, maintenance and reconfiguration of satellites, cost efficiency and simplification of the tool exchange in scientific exploration missions. SIROM is designed to be a common building block for European and possibly world future space robotics enabled missions.

In recent years, a trend for higher resolution has increased the entrance apertures of future optical payloads for both Astronomy and Earth Observation most demanding applications, resulting in new opto-mechanical challenges for future systems based on either monolithic or segmented large primary mirrors. Whether easing feasibility and schedule impact of tight manufacturing and integration constraints or correcting mission-critical in-orbit and commissioning effects, Active Optics constitutes an enabling technology for future large optical space instruments at ESA and needs to reach the necessary maturity in time for future mission selection and implementation. We present here a complete updated overview of our current R and D activities in this field, ranging from deformable space-compatible components to full correction chains including wavefront sensing as well as control and correction algorithms. We share as well our perspectives on the way-forward to technological maturity and implementation within future missions.

Integrated system health management (ISHM) technologies have been developed to address safety, replace time-based maintenance with condition-based maintenance, and to reduce life cycle costs. Traditional space system designs have focused on safety to minimize the risk to crew and to protect the public, astronauts and pilots, the NASA workforce, and high-value equipment and property. Systems have relied on high reliability components to provide the necessary safety margins and avoid operational mission failures. The current vision for future manned and unmanned space missions to the International Space Station, the Moon, Mars, and beyond, will require longer duration missions and will rely on complex assemblages of components. Increased mission duration and complexity increase the probability of operational mission failures that must be mitigated without jeopardizing safety or the objectives of the current or future missions that might reuse critical mission components. ISHM technology will be essential for providing near-real-time assessments of system capability, safety margins, and maintenance and sustainment requirements. The Applied Research Lab has conducted a series of workshops for NASA which focused on defining requirements for integrated system health monitoring and for the integration of health monitoring and control to provide intelligent self situational awareness (ISSA). The results of these workshops indicate that the benefits of ISHM and greater integration between ISHM and control include increased safety and mission assurance, the ability to rapidly respond to system failures, and decreased operator workload. Emerging open system standards such as OSA-EAI provide a framework for integrating system health monitoring with control functionality in spacecraft avionics systems. The purpose of this paper is to describe areas where system health monitoring can impact safety, reliability and sustainment in space applications and present the results of workshops conducted for NASA to identify requirements for the integration of health monitoring and control in future space systems

Sample return from asteroids and comets beyond the main belt is considered to be one of the most worthwhile future deep space missions [1]. Japan Aerospace Exploration Agency (JAXA) is currently entertaining a Jupiter Trojan sample return mission using a solar power sail [2], following the heritage of the Hayabusa sample return mission [3]. Because of high orbital energy corresponding to outer bodies, a sample return capsule (SRC) for such a future mission is expected to reenter the Earth’s atmosphere at velocities higher than 14 km/s and, hence, to encounter much severer aerodynamic heating environments than those of any past SRCs. Especially, the radiative heat transfer is considered to play a significant role in heat transfer processes in the shock layer, since the radiative heat transfer exponentially increases with the atmospheric flight velocity. To optimize the aerothermal design of the SRC and to minimize the mass of the thermal protection system (TPS) equipped with the SRC aeroshell, it is essentially required to accurately predict the aerothermal environments around the SRC along the reentry trajectory.

The Safe and Precise Landing Integrated Capabilities Evolution (SPLICE) project continues NASA's technology development for Precision Landing and Hazard Avoidance (PL&HA). The High-Performance Space Computing (HPSC) project manages a contract to build a multi core processor that is intended to be NASA's computing platform for future human and robotic spaceflight missions. This paper describes the flight computer for the PL&HA payload that will be used in SPLICE flight testing onboard suborbital rockets. This computer is being designed as a surrogate architecture for the HPSC chip, using a Xilinx Multi-Processor System on a Chip (MPSoC). Field testing with the surrogate architecture facilitates cross-agency experience with the HPSC and positions projects for future technology infusion opportunities. The MPSoC is hosted on a custom baseboard and interfaced to a second custom board that provides the sensor and vehicle interfaces. Early design trades for the SPLICE surrogate implementation are described. Preliminary performance testing on the surrogate platform using an optical navigation algorithm developed for the Orion vehicle is described, and shows 2.5 times execution speedup resulting from minimal modifications to the original code. In general, High Performance Computing/Embedded Computing (HPC/HPEC) required to address computational challenges in a wide range of NASA missions has consistently had challenges in implementation due to the diversity in the disciplines required to develop a solution. Typically, algorithm designers with expertise in the physics of the problem, and numeric approaches to solving the relations that model the physics, do not have expertise in processing architectures. There are strong dependencies between the overall performance of the system and the choices made in the modeling of the physics, the numerical approaches to solutions for the physical relations, and how these operations are mapped to computational resources in an architecture. To address this concern, a Model-Based Systems Engineering (MBSE) based concept for conducting multi-disciplinary co-design of the Guidance, Navigation, and Control (GN&C) algorithms, processing hardware configuration, and system software is introduced.

Since 2001, the In-Space Propulsion Technology (ISPT) program has been developing and delivering in-space propulsion technologies that will enable or enhance NASA robotic science missions. These in-space propulsion technologies are applicable, and potentially enabling, for future NASA flagship and sample return missions currently being considered. They have a broad applicability to future competed mission solicitations. The high-temperature Advanced Material Bipropellant Rocket (AMBR) engine, providing higher performance for lower cost, was completed in 2009. Two other ISPT technologies are nearing completion of their technology development phase: 1) NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 2) Aerocapture technology development with investments in a family of thermal protection system (TPS) materials and structures; guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; aerothermal effect models; and atmospheric models for Earth, Titan, Mars and Venus. This paper provides status of the technology development, applicability, and availability of in-space propulsion technologies that have recently completed their technology development and will be ready for infusion into NASA's Discovery, New Frontiers, SMD Flagship, or technology demonstration missions.

This paper proposes an engineering management model for NASA's future space exploration missions based on past experiences working with the International Partners of the International Space Station. The authors have over 25 years of combined experience working with the European Space Agency, Japan Aerospace Exploration Agency, Canadian Space Agency, Italian Space Agency, Russian Space Agency, and their respective contractors in the design, manufacturing, verification, and integration of their elements electric power system into the United States on-orbit segment. The perspective presented is one from a specific sub-system integration role and is offered so that the lessons learned from solving issues of technical and cultural nature may be taken into account during the formulation of international partnerships. Descriptions of the types of unique problems encountered relative to interactions between international partnerships are reviewed. Solutions to the problems are offered, taking into consideration the technical implications. Through the process of investigating each solution, the important and significant issues associated with working with international engineers and managers are outlined. Potential solutions are then characterized by proposing a set of specific methodologies to jointly develop spacecraft configurations that benefits all international participants, maximizes mission success and vehicle interoperability while minimizing cost.

In this article, we develop a novel hybrid control framework to address fast consensus seeking problems for multiagent dynamical systems. Specifically, we present hybrid distributed controller architectures for multiagent coordination to improve the transient performance of coordination tasks. The proposed controller architectures are predicated on some novel hybrid dynamic compensation structures involving the exchange of information between agents. A unique feature of the proposed framework is that the proposed controller architectures are hybrid and appear to achieve finite-time coordination, and hence significantly improve the transient performance of the closed-loop system. The overall closed-loop dynamics under any of these controller algorithms achieving consensus possesses discontinuous flows since the controller algorithms combine logical switchings with continuous dynamics, leading to impulsive differential equations. Several simulation results are provided to validate the proposed consensus protocols.

The National Space Policy of 1988 established the U.S.'s long range civil space goals, and has served to guide NASA's recent planning for future space mission operations. One of the major goals was to extend the human presence beyond Earth's boundaries and to advance the scientific knowledge of our solar system. In November, 1989, President Bush approved a revised Space Policy that essentially updated and reaffirmed the U.S. goals and activities. A broad spectrum of potential civil space mission opportunities and interests are currently being investigated by NASA to meet the espoused goals. Participation in many of these missions requires power systems with capabilities far beyond what exists today. In other mission examples, advanced power systems technology could enhance mission performance significantly. Power system requirements and issues that need resolution to ensure eventual mission accomplishment will be addressed, in conjunction with the ongoing NASA technology development efforts and the need for even greater innovative efforts to match the ambitious solar exploration mission goals.

In this paper we present a modular and distributed control architecture in order to achieve natural interaction and mobile manipulation task goals for a humanoid robot. We propose a hierarchically organized architecture with three levels and introduce the mapping of the functional features in this architecture into hardware and software modules. We also describe different functional features which have been realized and integrated into the whole control architecture.