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This viewgraph presentation evaluates absolute geolocation accuracy of OrbView-3, EROS-A, and SPOT-5 by comparing test imagery-derived ground coordinates to Ground Control Points using SOCET set photogrammetric software.
Although high altitude frequencies effects are removed at the time of basic image generation, low altitude (Yaw) effects are still present in form of affinity/angular affinity. They are effectively removed by additional parameters. Bundle block adjustment based on properly weighted ephemeris/altitude quaternions (BBABEQ) are not enough to remove the systematic effect. Moreover, due to the narrow FOV of the HRSI, position and altitude are highly correlated making it almost impossible to separate and remove their systematic effects without extending the geometric model (Self-Calib.) The systematic effects gets evident on the increase of accuracy (in terms of RMSE at GCPs) for looser and relaxed ground control at the expense of large and strong block deformation with large residuals at check points. Systematic errors are most freely distributed and their effects propagated all over the block.
The worldwide effort to grow nanotechnology, rather than use lithography, focuses on diatoms, single cell eukaryotic algae with ornate silica shells, which can be replaced by oxides and ceramics, or reduced to elemental silicon, to create complex nanostructures with compositions of industrial and electronics importance. Diatoms produce an enormous variety of structures, some of which are microtubule dependent and perhaps sensitive to microgravity. The NASA Single Loop for Cell Culture (SLCC) for culturing and observing microorganisms permits inexpensive, low labor in-space experiments. We propose to send up to the International Space Station diatom cultures of the three diatom species whose genomes are being sequenced, plus the giant diatoms of Antarctica (up to 2 mm diameter for a single cell) and the unique colonial diatom, Bacillaria paradoxa. Bacillaria cells move against each other in partial synchrony, like a sliding deck of cards, by a microfluidics mechanism. Will normal diatoms have aberrant pattern and shape or motility compared to ground controls? The generation time is typically one day, so that many generations may be examined from one flight. Rapid, directed evolution may be possible running the SLCC as a compustat. The shell shapes and patterns are preserved in hard silica, so that the progress of normal and aberrant morphogenesis may be followed by drying samples on a moving filter paper "diatom tape recorder". With a biodiversity of 100,000 distinct species, diatom nanotechnology may offer a compact and portable nanotechnology toolkit for exploration anywhere.
A lunar outpost will involve a habitat with an integrated set of hardware and software that will maintain a safe environment for human activities. There is a desire for a paradigm shift whereby crew will be the primary mission operators, not ground controllers. There will also be significant periods when the outpost is uncrewed. This will require that significant automation software be resident in the habitat to maintain all system functions and respond to faults. JSC is developing a testbed to allow for early testing and evaluation of different autonomy architectures. This will allow evaluation of different software configurations in order to: 1) understand different operational concepts; 2) assess the impact of failures and perturbations on the system; and 3) mitigate software and hardware integration risks. The testbed will provide an environment in which habitat hardware simulations can interact with autonomous control software. Faults can be injected into the simulations and different mission scenarios can be scripted. The testbed allows for logging, replaying and re-initializing mission scenarios. An initial testbed configuration has been developed by combining an existing life support simulation and an existing simulation of the space station power distribution system. Results from this initial configuration will be presented along with suggested requirements and designs for the incremental development of a more sophisticated lunar habitat testbed.
Objective: Compare vendor-provided image coordinates with known references visible in the imagery. Approach: Use multiple, well-characterized sites with >40 ground control points (GCPs); sites that are a) Well distributed; b) Accurately surveyed; and c) Easily found in imagery. Perform independent assessments with independent teams. Each team has slightly different measurement techniques and data processing methods. NASA Stennis Space Center. South Dakota State University.
The J-2X is an expendable liquid hydrogen (LH2)/liquid oxygen (LOX) gas generator cycle rocket engine that is currently being designed as the primary upper stage propulsion element for the new NASA Ares vehicle family. The J-2X engine will contain abort logic that functions as an integral component of the Ares vehicle abort system. This system is responsible for detecting and responding to conditions indicative of impending Loss of Mission (LOM), Loss of Vehicle (LOV), and/or catastrophic Loss of Crew (LOC) failure events. As an earth orbit ascent phase engine, the J-2X is a high power density propulsion element with non-negligible risk of fast propagation rate failures that can quickly lead to LOM, LOV, and/or LOC events. Aggressive reliability requirements for manned Ares missions and the risk of fast propagating J-2X failures dictate the need for on-engine abort condition monitoring and autonomous response capability as well as traditional abort agents such as the vehicle computer, flight crew, and ground control not located on the engine. This paper describes the baseline J-2X abort subsystem concept of operations, as well as the development process for this subsystem. A strategy that leverages heritage system experience and responds to an evolving engine design as well as J-2X specific test data to support abort system development is described. The utilization of performance and failure simulation models to support abort system sensor selection, failure detectability and discrimination studies, decision threshold definition, and abort system performance verification and validation is outlined. The basis for abort false positive and false negative performance constraints is described. Development challenges associated with information shortfalls in the design cycle, abort condition coverage and response assessment, engine-vehicle interface definition, and abort system performance verification and validation are also discussed.
A general overview of the Ikhana Uninhabited Air System (UAS) is presented. The contents include: 1) Ikhana UAS; 2) Ikhana UAS / Ground Control Station (GCS); 3) Ikhana UAS / Antennas; 4) Western States Fire Mission 2007 Partners; 5) FAA Certificate of Authorization (COA); 6) Western States Fire Missions (WSFM) 2007; 7) WSFM 1-4 2007; 8) California Wildfire Emergency Response 2007; 9) WSFM 5-8 Emergency Response 2007; 10) WSFM Achievements; and 11) WSFM Challenges.
The NASA Ikhana unmanned aerial vehicle (UAV) is a General Atomics Aeronautical Systems Inc. (San Diego, California) MQ-9 Predator-B modified to support the conduct of Earth science missions for the NASA Science Mission Directorate and, through partnerships, other government agencies and universities. It can carry over 2000 lb of experiment payloads in the avionics bay and external pods and is capable of mission durations in excess of 24 hours at altitudes above 40,000 ft. The aircraft is remotely piloted from a mobile ground control station (GCS) that is designed to be deployable by air, land, or sea. On-board support capabilities include an instrumentation system and an Airborne Research Test System (ARTS). The Ikhana project will complete GCS development, science support systems integration, external pod integration and flight clearance, and operations crew training in early 2007. A large-area remote sensing mission is currently scheduled for Summer 2007.
Annapolis, Maryland-based designAmerica Inc., a small aerospace company specializing in the development and delivery of ground control systems for satellites and instrumentation, assisted Goddard Space Flight Center in the development of the ASIST software, a real-time command and control system for spacecraft development, integration, and operations. It was designed to be fully functional across a broad spectrum of satellites and instrumentation, while also being user friendly. The company now has rights to commercial use of the program and is offering it to government and industry satellite designers.
This viewgraph presentation reviews Ikhana's project goals: (1) Develop an airborne platform to conduct Earth observation and atmospheric sampling science missions both nationally and internationally, (2) develop and demonstrate technologies that improve the capability of UAVs to conduct science collection missions, (3) develop technologies that improve manned and unmanned aircraft systems, and (4) support important national UAV development activities. The criteria that guided the selection of the aircraft are listed. The payload areas on Ikhana are shown and the network that connects the systems are also reviewed. The data recorder is shown. Also the diagram of the Airborne Research Test System (ARTS) is reviewed. The Mobile Ground Control Station and the Mobile Ku SatCom Antenna are also shown and described.
Two approaches were compared to the Crew Exploration Vehicle (CEV) Avionics Integration Laboratory (CAIL) approach: the Flat-Sat and Shuttle Avionics Integration Laboratory (SAIL). The Flat-Sat and CAIL/SAIL approaches are two different tools designed to mitigate different risks. Flat-Sat approach is designed to develop a mission concept into a flight avionics system and associated ground controller. The SAIL approach is designed to aid in the flight readiness verification of the flight avionics system. The approaches are complimentary in addressing both the system development risks and mission verification risks. The following NESC team findings were identified: The CAIL assumption is that the flight subsystems will be matured for the system level verification; The Flat-Sat and SAIL approaches are two different tools designed to mitigate different risks. The following NESC team recommendation was provided: Define, document, and manage a detailed interface between the design and development (EDL and other integration labs) to the verification laboratory (CAIL).
This paper describes experience using Obstacle Analysis to identify contingency requirements on an unpiloted aerial vehicle. A contingency is an operational anomaly, and may or may not involve component failure. The challenges to this effort were: ( I ) rapid evolution of the system while operational, (2) incremental autonomy as capabilities were transferred from ground control to software control and (3) the eventual safety-criticality of such systems as they begin to fly over populated areas. The results reported here are preliminary but show that Obstacle Analysis helped (1) identify new contingencies that appeared as autonomy increased; (2) identify new alternatives for handling both previously known and new contingencies; and (3) investigate the continued validity of existing software requirements for contingency handling. Since many mobile, intelligent systems are built using a development process that poses the same challenges, the results appear to have applicability to other similar systems.
Initial mapping of Mars began with the early Mariner 4, 6 and 7 flybys in the 1960's. Mariner 9 obtained the first global coverage of Mars in 1971. Viking Orbiters 1 and 2 added new and higher resolution global coverage. The US Geological Survey produced the first digital global cartographic map products in black and white and in color, the mosaicked digital image models (MDIMs). In 1989, the Phobos 88 mission added imaging as well as multispectral mapping of Mars in the equatorial region. The Mars Global Surveyor (MGS) added to the black and white and color global coverage. The most important development for Mars cartography occurred on MGS with its global coverage of Mars using the Mars Observer Laser Altimeter (MOL A) producing precision ground control in latitude, longitude and radius. The next version of the MDIM was produced at 230 m spatial resolution using MOLA precision cartographic control. The Mars Odyssey mission THEMIS instrument has completed its global infrared mapping of Mars at 100 m spatial resolution. The Mars Express mission is completing its global coverage of Mars in stereo at 100 m spatial resolution or better. MGS, Odyssey and Mars Express continue to provide limited surface coverage at the 1 to 20 m resolution. Currently the new Mars Reconnaissance Orbiter is producing images at the 10's of cm level. All of these datasets provide a rich and historic perspective of Mars covering nearly five decades and allow global cartographic map products to be produced in visual and infrared at the 100 m level with specialized cartographic maps being produced for landing sites at the meter or sub-meter spatial resolution level. This work was produced at the Jet Propulsion Laboratory, California Institute of Technology under contract to the National Aeronautics and Space Administration, NAS 7-7120.5d, within the NASA Mars Data Analysis Program and the MGS, Odyssey, Mars Express and MRO Participating Scientist Programs.
Stability testing is a tool used to access shelf life and effects of storage conditions for pharmaceutical formulations. Early research from the International Space Station (ISS) revealed that some medications may have degraded while in space. This potential loss of medication efficacy would be very dangerous to Crew health. The aim of this research project, Stability of Pharmacotherapeutic Compounds, is to study how the stability of pharmaceutical compounds is affected by environmental conditions in space. Four identical pharmaceutical payload kits containing medications in different dosage forms (liquid for injection, tablet, capsule, ointment and suppository) were transported to the ISS aboard a Space Shuttle. One of the four kits was stored on that Shuttle and the other three were stored on the ISS for return to Earth at various time intervals aboard a pre-designated Shuttle flight. The Pharmacotherapeutics laboratory used stability test as defined by the United States Pharmacopeia (USP), to access the degree of degradation to the Payload kit medications that may have occurred during space flight. Once these medications returned, the results of stability test performed on them were compared to those from the matching ground controls stored on Earth. Analyses of the results obtained from physical and chemical stability assessments on these payload medications will provide researchers additional tools to promote safe and efficacious medications for space exploration.
The Mobile Servicing System (MSS) is a complex robotics system used extensively in the assembly, inspection and maintenance of the International Space Station (ISS). Its external components are comprised of the Space Station Remote Manipulator System (SSRMS), the Mobile Base System (MBS), and the Special Purpose Dexterous Manipulator (SPDM or "Dextre"). Dexterous robotic maintenance operations on the ISS are now enabled with the launch and deployment of "Dextre" in March 2008 and the recently completed commissioning to support nominal operations. These operations include allowing for maintenance of the MSS capability to be executed uniquely via robotic means. Examples are detailed inspection and the removal and replacement of On-orbit Replaceable Units (ORUs) located outside the pressurized volume of the ISS, alleviating astronauts from performing numerous risky and time-consuming extra-vehicular activities (EVAs). In light of the proposed extension of the ISS to 2020 and beyond, "Dextre" can also be seen as a resource for the support and conduct of external ISS experiments. "Dextre" can be utilized to move experiments around ISS, as test bed for more elaborate experiments outside the original design intent, and as a unique platform for external experiments. This paper summarizes the status of "Dextre", its planned use, and future potential for dexterous operations on the ISS. Lessons learned from the planning and execution of SPDM commissioning are first introduced, and significant differences between "Dextre" and SSRMS operations are discussed. The use of ground control as the predominant method for operating "Dextre" is highlighted, along with the benefits and challenges that this poses. Finally, the latest plans for dexterous operations on ISS are summarized including visiting vehicle unloading, nominal maintenance, and operations of a more experimental flavor.
Topics discussed include: a) UAV s at NASA Dryden, Past and Present; b) Why Do We Flight Test?; c) The Blended (or Hybrid) Wing-Body Advantage; d) Program Objectives; e) The X-48B Vehicle and Ground Control Station; and f) Flight Test Highlights & Video.
At the Kennedy Space Center, I engaged in the research and development of electrical ground support equipment for NASA's Constellation Program. Timing characteristics playa crucial role in ground support communications. Latency and jitter are two problems that must be understood so that communications are timely and consistent within the Kennedy Ground Control System (KGCS). I conducted latency and jitter tests using Alien-Bradley programmable logic controllers (PLCs) so that these two intrinsic network properties can be reduced. Time stamping and clock synchronization also play significant roles in launch processing and operations. Using RSLogix 5000 project files and Wireshark network protocol analyzing software, I verified master/slave PLC Ethernet module clock synchronization, master/slave IEEE 1588 communications, and time stamping capabilities. All of the timing and synchronization test results are useful in assessing the current KGCS operational level and determining improvements for the future.
Data from the two MODIS instruments have been accurately geolocated (Earth located) to enable retrieval of global geophysical parameters. The authors describe the approach used to geolocate with sub-pixel accuracy over nine years of data from M0DIS on NASA's E0S Terra spacecraft and seven years of data from MODIS on the Aqua spacecraft. The approach uses a geometric model of the MODIS instruments, accurate navigation (orbit and attitude) data and an accurate Earth terrain model to compute the location of each MODIS pixel. The error analysis approach automatically matches MODIS imagery with a global set of over 1,000 ground control points from the finer-resolution Landsat satellite to measure static biases and trends in the MO0lS geometric model parameters. Both within orbit and yearly thermally induced cyclic variations in the pointing have been found as well as a general long-term trend.