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Reinventing Space: Design of Low-Cost Space Missions Course |
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Past Conference Papers:
Mission Design
| Paper Number RS1-2003-3001: Microsatellite Deployment On Demand | |
| Michael Hurley (NRL), Joe Hauser (NRL), Timothy Duffey (NRL) | |
| View/Download:Presentation | Paper | |
| Abstract: This paper discusses the technical, operational, and architectural issues that must be addressed to develop a tactical, launch on demand microsatellite capability. The new paradigm of threats to national security requires the U.S. to focus on a dispersed and often asymmetric threat. This portends military engagement in possibly many small unconventional conflicts around the globe. Meeting the space-based demand for sensors and communications for this new style of warfare requires an agile response, with launch on demand tactical satellites that can be matched to each conflict’s unique needs. Having small, robust payloads literally “off the shelf” and an agile, on demand launch capability would solve this problem. Today’s microsatellites, in the sub 100 kg class, are poised to perform useful tactical missions in the near future. Tactical microsatellites, “TacSats”, offer a best-of-both-worlds combination of characteristics: the low-cost, tailored payloads and on-demand responsiveness of unmanned aerial vehicles (UAVs); along with global access to denied areas, broad coverage, non-vulnerability, and long duration characteristics of traditional satellites. To recognize these benefits, a TacSat system must also include an alternative launch vehicle/process, highly automated and capable satellites, and tasking and data distribution directly by/to the forces. Each of these system features is under development. The Defense Advanced Research Projects Agency (DARPA), U.S. Air Force, Missile Defense Agency (MDA), U.S. Navy, and industry are actively working to lower launch costs and increase timeliness. Current microsatellite and payload technologies are being developed to provide the necessary automation and capability with a 100 kg target mass. Finally, the combination of direct downlink and the use of the government’s global classified network, SIPRNET, will allow tasking and data distribution directly to the forces. | |
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| Paper Number RS1-2003-8004: DARPA's Rapic Access Small Cargo Affordable Launch (RASCAL) Program | |
| Preston Carter (DARPA), Owen Brown (Booz Allen Hamilton), Tharen Rice (APL) | |
| View/Download:Presentation | Paper | |
| Abstract: RASCAL is a revolutionary space access program initiated by the Defense Advanced Research Projects Agency (DARPA). RASCAL will demonstrate the capability to launch microsatellites into low earth orbit routinely and on short notice using an air-launch system architecture. A propulsion enhancement – Mass Injection Pre-Compressor Cooling (MIPCC) - allows the air vehicle to obtain high-energy flight conditions and provides the capability for exoatmospheric staging of an expendable rocket with satellite payload attached. This architecture effectively reduces recurring launch costs, which are targeted to be $750,000 per launch. | |
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| Paper Number RS1-2003-A001: Responsive Space: A Launch Vehicle Designer's Viewpoint | |
| Antonio Elias (OSC) | |
| View/Download:Presentation | |
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| Paper Number RS2-2004-4001: Responsive Space Operations Architecture Development for the National Security Space Community | |
| Patrick Frakes (NSSO), Paul Popejoy (The Aerospace Corporation) | |
| View/Download:Presentation | Paper | |
| Abstract: The fundamental decision criteria for accepting the cost, risk, performance, and responsiveness of National Security Space (NSS) capabilities are still largely driven by the strategic imperatives of the late 1950s, even though the world has changed significantly since 1989. These decision criteria inform virtually every aspect of space acquisition and operations; risk mitigation strategies; and the NSS approach to the repair, maintenance, modernization, and replenishment of space capabilities. The National Security Space Architect (NSSA) will begin development in FY04 of a long-term Responsive Space Operations (RSO) Architecture. The RSO Architecture will identify approaches to achieve the longterm (adaptability), mid-term (flexibility), and short-term responsiveness (agility) that space capabilities will need to respond to dynamic world environments, national priorities, and operational requirements. For the Responsive Space Conference II, NSSA will outline the problem to be addressed, and the NSSA’s approach to reviewing, understanding, identifying and assessing alternative architectures, and possibly recommending fundamental changes in the overall national security space architecture. The objective is to achieve the right level of responsiveness for the nation’s 21st century space capabilities. | |
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| Paper Number RS2-2004-5001: Real-Time Mosaic - Rapid Response Hight Resolution Imaging from Space | |
| Alex da Silva Curiel (SSTL), Phillip Davies (SSTL), Stuart Eves (SSTL), Lee Broland (SSTL), Martin Sweeting (SSTL) | |
| View/Download:Presentation | Paper | |
| Abstract: An imaging constellation mission is proposed to provide near-continuous surveillance of regional activity. By introducing a multiple plane constellation of small Earth Observation satellites, it is possible to monitor selected parts of the entire globe several times during daylight. Using off-the-shelf microsatellites ensures the program is responsive in the deployment phase as well as in the operational phase. The paper describes the basic Disaster Monitoring Constellation programme as has been implemented, which already delivers daily imagery. It also describes the system trades of the regional imaging constellations, and outlines the scope of the performance that could be obtained from such a system. A cost model illustrates that the balance between launch and space segment costs must be reached by considering suitable replacement strategies, and that the system is highly sensitive to requirement creep. Finally, it is shown that the use of cost effective, small satellites leads to solutions previously thought to be out of reach of Earth Science and Government customers. | |
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| Paper Number RS2-2004-6004: Department of Defense R&D Responsive Spaceflight | |
| Taylor Locker (SMC), Major Timothy Sumrall (SMC) | |
| View/Download:Presentation | Paper | |
| Abstract: This paper will discuss a new strategy for repeatable launching of Space Research, Development, Test and Evaluation (RDT&E) missions in 12-18 months versus 48 months using mechanisms that are in place today. DoD research and development (R&D) Responsive Space (RRS) is targeting a new way of doing business by creating a standard –service provider relationship. This new standard relationship will be forged through an alliance of government organizations. This alliance of government organizations must commit resources (manning and funding) to meet the timelines established for RRS. This paper will also discuss four RRS scenarios. These are dedicated launch vehicle (LV) (build spacecraft), dedicated LV (spacecraft bought), piggyback on host spacecraft or LV, and secondary satellite deployed form LV. These scenario’s will explore the technical envelope, barriers, considerations, and schedule realities of RRS. | |
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| Paper Number RS2-2004-A007: The Architect's Perspective on Responsive Space | |
| Rick Geraci (NSSO) | |
| View/Download:Presentation | |
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| Paper Number RS3-2005-2001: Coverage, Responsiveness, and Accessibility for Various "Responsive Orbits" | |
| James R. Wertz (Microcosm) | |
| View/Download:Presentation | Paper | |
| Abstract: We have evaluated 5 potential Responsive Orbits with the following conclusions with respect to coverage, responsiveness, payload to orbit for a small launch vehicle, and missions that they would be best suited for: • Cobra Orbits provide up to 4 hours of continuous access per day, 10 hours mean response time, low payload mass to orbit, very poor optical resolution, and are best used for communications. • Magic Orbits provide up to 1 hour of continuous access per day, 12 hours mean response time, low to moderate payload mass to orbit, poor optical resolution, and are also best for communications. • LEO Sun Synchronous Orbits provide 5 minutes of coverage once or twice per day, 6 hour mean response time, moderate payload mass to orbit, excellent optical resolution, and are best suited for visual or radar observations. • LEO Fast Access Orbits provide 5 minutes of coverage once or twice per day, 45 minute mean response time, moderate to high payload mass to orbit, excellent optical resolution, and are best suited for highly responsive visual or radar observations. • LEO Repeat Coverage Orbits provide 5 minutes of coverage every 90 minutes for 4 or 5 times in a row, 9 hour mean response time, high payload mass to orbit, excellent optical resolution, and are best suited for repeated visual or radar observations. Responsive orbits have the potential to provide means for communications and high-resolution surveillance anywhere in the world within hours of an identified demand. Collectively, these orbits provide excellent opportunities for transforming space from a strategic to a tactical asset and for doing missions that cannot now be done. Coupled with the launch vehicles being developed under the AF/DARPA/NASA FALCON program and emerging smallsat technology, there is excellent potential for new, low-cost missions that can transform the way space is used. | |
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| Paper Number RS5-2007-1002: Clustered Architecture for Responsive Space | |
| Gregory A. Orndorff (Johns Hopkins University Applied Physics Laboratory), Buruce F. Zink (Johns Hopkins University Applied Physics Laboratory), John D. Cosby (Science Applications International) | |
| View/Download:Presentation | Paper | |
| Abstract: The tenets of operationally responsive space need to be addressed and implemented systematically, in a supportive and enabling framework. We discuss a proposed satellite architecture consisting of multiple clusters of satellites in geosynchronous orbit, providing standard communications and propulsion services to client satellites flying within the clusters. This allows the offloading of propellant and mission communications and the use of the cluster’s services as a utility, enabling smaller, lighter, cheaper mission satellites. We show how offloading mission communications from satellites in favor of a high-speed wireless local area network in space enables efficient use of both space and ground communications capabilities. We show how enabling operators to utilize communications and delta-V as commodities enables highly responsive operations, on the order of days for major satellite constellation reconfigurations, and how these services themselves form the foundation of truly responsive space operations. | |
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| Paper Number RS5-2007-1003: Future Optical Surveillance Using Small Satellites | |
| Stuart Eves (Surrey Satellite Technology) | |
| View/Download:Presentation | Paper | |
| Abstract: The paper will describe the successes of the TopSat and Beijing-1 surveillance missions, and will indicate how the lessons-learned from these satellites will influence the design of the next generation of optical surveillance constellations. Specifically, the ability to collect data with multiple sensors at different resolutions over different areas allows the satellites to be used responsively in different modes, depending upon the nature of the crisis situation. The agility of small satellites allows them to use Ground Motion Compensation modes to collect data over a wider range of illumination conditions, and the paper will illustrate how this capability allows a broader range of orbits to be considered, (with consequent implications for revisit rates, and hence responsiveness). This agility can also be used to implement in-pass stereo and wide-swath imaging modes when required. With the launch of the RapidEye constellation now imminent, the paper will also describe how the design of the next generation of satellites will be specifically designed for launch as part of a constellation. | |
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| Paper Number RS4-2006-1001: System Architecting Challenges of Changing Missions for a Flexible Mission Spacecraft | |
| John Bystroff (University of Southern California) | |
| View/Download:Presentation | Paper | |
| Abstract: Air Force Space Command has been a strong advocate of an operational responsive space (ORS) capability. Operationally responsive space, as described by Arthur Cebrowski, Director of Force Transformation, Office of the Secretary of Defense, involves establishing a mission need “driven by adaptive contingency planning cycles rather than predictive futures or scripted acquisition periods.” In practical terms, this means for a space system to be considered operationally responsive, identified mission needs require fulfillment within days or weeks, not the years the current acquisition process requires. One concept to fulfill responsive space requirements involves placing a flexible mission spacecraft (FMS) on-orbit. An FMS would have the capability to re-configure its bus and payload hardware and software to meet emerging mission requirements. Various new technologies, such as Software Defined Radio (SDR) and micro electro mechanical systems (MEMS) enable considering how to create a satellite with a malleable architecture. However, an FMS presents a significant system architecting challenge by its malleability. The challenge is not merely in its initial deployment, but in changing missions. To successfully support new mission requirements, an FMS must not only be able to change its own architecture, but it must be integrated with a mission architecture on the ground. It must support interfaces for the new mission along the entire stack of layered protocols from physical to application. The purpose of this paper is to highlight the system architectural challenges associated with an FMS in transitioning from supporting one mission to supporting a different one within the time-frame demanded of an “operationally responsive space system.” The challenges are first addressed with respect to satellite design concerns. The interface challenges with the ground mission infrastructures are then described with reference to the Open System Interconnect (OSI) model. Finally, it is proposed that the traditional waterfall spacecraft architecting approach is not suited to supporting an FMS mission change within the constraints demanded by ORS. Rather, the characteristics of the architecting environment for changing an on-orbit satellite design match closely with the situation faced in software development. Therefore, it is proposed that a spiral software development process provides a more viable architecting approach when changing an FMS mission. | |
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| Paper Number RS4-2006-1002: Fractionated Space Architectures: A Vision for Responsive Space | |
| O. Brown (Defense Advanced Research Projects Agency), Paul Eremenko (Booz Allen Hamilton) | |
| View/Download:Presentation | Paper | |
| Abstract: The advent of the integrated circuit some four decades ago set off mankind’s insatiable thirst for computational power. The quest to quench this desire led to the development of increasingly more sophisticated computers. Microchips sprouted ever greater numbers of transistors, choking buses, and forcing memory banks to struggle to keep up. The novelty of micro- and minicomputers was quickly trumped by the sheer computational prowess of supercomputers. And so the trend continued. In a matter of two decades, however, this drive towards greater processing power culminated in mammoth mainframes whose rapidly increasing complexity, fragility, and cost quickly outpaced the capability gains. A scant few years into the second decade of the era of the integrated circuit, the availability of inexpensive, mass-produced microcomputers, and the advent of fast, seamless internetworking ensured the relegation of the large monolithic mainframes to obsolescence and obscurity. Spacecraft have followed a trajectory that is uncannily parallel (and, of course, technologically intertwined) to the history of high-end computing. Borrowing the historical analogy, we posit that the era of distributed space architectures has likewise arrived. The gargantuan monolithic systems deployed to orbit today have grown too large, too complex, too fragile, and consequently much too expensive; furthermore, these trends have not been offset by commensurately rapid growth in capability. We propose a fractionated architecture for space systems, whereby a satellite is decomposed into a heterogeneous set of components which interact wirelessly. In the extremum, the fundamental functionality of most space systems is the reflection of photons back to earth. Thus, assuming that the requisite photon collection, processing, and re-radiation can be accomplished, the spacecraft need be nothing more than a collection of free-floating “pixie dust.” In the realm of the foreseeable technological future, however, there are a handful of schema for severing and distributing the functionality of a monolithic spacecraft. Perhaps the most basic is fractionating the spacecraft along its data channels, resulting in a loose cluster of networked spacecraft modules. Somewhat more challenging is also fractionating the power system and disseminating power wirelessly among the modules. At the technological horizon is also fractionating the propulsion and stationkeeping functionality, also necessitating the wireless transmission of forces and torques. The fractionated architecture is likely to incur an aggregate mass impact versus its monolithic counterpart (although it is noteworthy that at least one massive component may shrink – the flywheels necessary to ensure payload pointing accuracy need only be responsible for stabilizing and pointing the payload module, not the entire spacecraft). The impact on overall system cost is ambiguous since the cost impact due to greater system mass is at least partially offset by learning curve and mass production effects across the multitude of modules. For a constant required level of functionality, however, the fractionated architecture dramatically outperforms its monolithic counterparts in its value proposition. It affords its user/operator greater flexibility in the form of system scalability, reconfigurability, and adaptability (including multi-payload functionality). It dramatically increases robustness and survivability. It allows the isolation of the payload for both improved security and increased pointing accuracy. It lowers possible increases in lifecycle cost and decreases schedule risk by decorrelating failure probabilities of the various component subsystems and multiple payloads. It improves responsiveness by allowing incremental capability deployment, by enabling the utilization of small launch vehicles for the emplacement of massive orbital capabilities, and by shifting the deployment decision chain from the strategic to the tactical level. Perhaps most importantly – and much like the internetworked microcomputer – it commoditizes the space industry and transforms it from an exotic boutique to a customer-driven, cost-competitive enterprise. The technologies needed to make fractionated space systems a reality are well within reach. They potentially include responsive and inexpensive small launch vehicles, highly secure ultra wideband inter-module data links (which may also provide relative navigation capabilities for the spacecraft modules), efficient radio frequency power transmission, passively stable Keplerian cluster orbits, and mass-produced, inexpensive, space-qualified satellite components (many with their legacy in the newly-emergent field of unmanned aerial vehicles). More esoteric technology options include very high frequency power beams, laser power transmission, and remote force and torque transmission through electromagnetic induction. The Defense Advanced Research Projects Agency (DARPA) has been studying the fractionated architecture concept and is poised to commence an initiative entitled F6 – short for Future Fast, Flexible, Fractionated Formation-Flying Spacecraft utilizing Information eXchange, and incidentally a tornado of unimaginable strength on the Fujitsu scale – that will mature the associated technological, architectural, and organizational advancements necessary for an onorbit demonstration of a fractionated spacecraft. A brief discussion of the vision for F6 concludes. | |
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| Paper Number RS4-2006-2001: Responsive Air Launch Using F-15 Global Strike Eagle | |
| Timothy T. Chen (Boeing), Preston W. Ferguson (Boeing), David A. Deamer (Boeing) | |
| View/Download:Presentation | Paper | |
| Abstract: A near term military need exists for a capability to execute global strike, responsive spacelift and space control missions. This paper presents an innovative concept based on integrating off-the-shelf components to provide this capability, while avoiding technology development risk. The concept would utilize an F-15E with minimal modifications to provide a reusable first stage for the F-15GSE (Global Strike Eagle). The upper stages of the F-15GSE would consist of currently available solid rocket motors packaged to meet the mission requirements. The F-15GSE concept could provide an “all azimuth” capability from a single CONUS base while reducing the Delta-V required for orbital insertion by 5000 fps versus a ground launch rocket system. Advantages of an F-15GSE system include: increased mission flexibility, rapid response time without deployment of assets, multiple basing options and covert launches. Operational missions could be completed within two hours while on alert status with minimal infrastructure from CONUS or remote bases. Initially this concept could provide a low-cost demonstration of global strike, while military operational capability could be met with an expansion of fleet size. The F-15GSE would be capable of global reach with delivery of munitions including the Common Aero Vehicle (CAV) and also provide a LEO launch capability for microsats. Planned future upgrades are available to enhance capability for delivering heavier ballistic and orbital payloads. | |
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| Paper Number RS4-2006-3002: Responsive Tactical Space Using Micro-Satellites and Aerial Launching: The Prespective of a Small Nation | |
| Col. (Res.) Yoram Ilan-Lipovsky (Space and UAV Center), Tal Inbar (Space Research Center of the Fisher Institute for Air & Space Strategic Studies, Israel) | |
| View/Download:Presentation | Paper | |
| Abstract: During recent years, a growing interest in the world space community has awakened, regarding a new approach in the field of space technology. This approach is based on a new and revolutionary look at the needs of small nations in space and on technological innovations as well. The importance of responsive space for civilian purposes and for defense use – at the tactical level will be presented in detail in the article and presentation. Our Vision calls for many satellites working together in constellations on low earth orbit, providing continuous target coverage. Some of the satellites would be launched on demand from military or civilian aircrafts and will be placed in optimal and focused orbits. The platforms will be Micro Satellites. Among other aspects, the paper will deal with civil and defense needs and the relevancy of emerging technologies such as miniaturization, ion driven thrusters, Nano-technologies, laser communication, data fusion and advanced imaging, to the realization of this vision. The article will describe the unique status of a small nation, such as the state of Israel, and the benefits it could gain from responsive space guidelines, especially in the fields of aerial launch and micro satellites. The paper will address all aspects of the Responsive tactical micro satellites vision, applicable for a small nation, such as: • Analysis of the needs – military and civilian • Defining future missions for TMS (Tactical Micro Satellites) • A comprehensive study of the Launch On Demand (LOD) concept and focused orbits idea • Technical and financial aspects • Aerial Launching – detailed analysis of 2 main alternatives – launch from a fighter plane (such as the F-15) and from an airliner (such as 747 or 767) • Micro Satellites – architecture, basic design, the bus, payloads, propulsion and orbits • Constellations and satellite formations flying • The very low Earth orbit environment | |
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| Paper Number RS4-2006-4006: A TACSAT & ORS Update Including Tacsat-4 | |
| Col. Tom Doyne (OSD), Cdr. Greg Glaros (OSD), Peter Wegner (AFRL), Lt. Col. Randy Riddle (SMC Detachment 12), Mike Hurley (Naval Research Laboratory), Ken Weldy (Naval Research Laboratory), Chris Garner (Naval Research Laboratory) | |
| View/Download:Presentation | Paper | |
| Abstract: In May of 2003, the Office of the Secretary of Defense’s Office of Force Transformation (OFT) undertook an initiative to perform Operationally Responsive Space (ORS) experimentation. Three years later TacSat-1, 2, 3, and 4 experiments are all underway. TacSat experiments are now jointly selected each year via an iterative mission development process engaging the operational community, COCOMs & Services, and the DoD S&T community. TacSat experimentation leadership and funding has largely transitioned to the DoD S&T community with OSD’s Office of Force Transformation continuing to provide guidance and bus standards development. Each TacSat experiment tests key elements needed for an operational system by taking frequent tangible steps to spiral capability and receive operational feedback, while moving toward an acquisition. The TacSat-4 experiment will use the prototype ORS system-level bus standards and fly in a “low” Highly Elliptical Orbit (HEO) enabling a new set of ORS missions that require dwell, such as communications. In addition to experimentation, ORS has made significant strides toward an operational system. The formal ORS requirements are being developed in the Joint Capabilities Interface Development System (JCIDS) process and preparation of a Joint Program Office, formally planned for FY08, has also begun. This paper discusses the above and, for context, includes portions of the 2003, 2004, and 2005 papers. | |
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| Paper Number RS4-2006-4005: Responsive Space's Spacecraft Design Tool (SDT) | |
| Robert Strunce (Star Technologies), Fred Eckert (Star Technologies), Craig Eddy (Star Technologies) | |
| View/Download:Presentation | Paper | |
| Abstract: Star Technologies Corporation has developed a “.Net Framwork Simulation Architecture”, “Spacecraft Design Tool” (SDT), which is an open framework for Responsive Space’s rapid design concept spanning mission capture to deployment. SDT has been incorporated in all the test cells at AFRL’s Responsive Space Test Bed. SDT is integrated into the Mission Design phase for spacecraft simulation and analysis as well as providing the spacecraft dynamics/kinematics, earth environment, and sensor/actuator models in the real time hardware-in-the-loop (HITL) test cells. SDT can simulate a sensor/actuator, or interface to its respective hardware emulator or interface to the actual hardware through the Responsive Space’s Plug-n-Play (PnP) electronic environment. SDT provides a true software PnP environment where the User can seamlessly inherit properties from within SDT as well as add his own component or subsystem capabilities such as complex propulsion or electrical power subsystem. SDT has a 3D Visual game engine for display of the earth, sun, moon as well as multiple articulated spacecraft. SDT has been used to model TacSat2, a generic Responsive Space satellite, and TacSat3. SDT provides an environment for rapid prototyping of spacecraft using true software PnP of components and subsystems. In other words, the SDT application recognizes new components such as attitude control sensors and actuators in the same way that your computer recognizes that a new printer has been added. This is accomplished through the latest software technologies of COM and .NET Framework. The .NET Framework provides a higher level of interoperability than COM especially over networks and the internet where COM is a subset of the overall capability. Under the .NET Framework, objects such as a specific Sun Sensor can be written in any language (C#, C++, Fortran, ADA, Basic, Perl) and execute on different computer platforms (PC, PowerPC, Sun) and under different operating systems (Windows, Solaris, Linux). Although SDT is currently aimed at spacecraft, the “.Net Framwork Simulation Architecture” can be applied to any multi-body dynamic system such as launch vehicles, robotics or land rovers. SDT has supported NASA efforts in electro-dynamic tethers as well as tethers employed in future NASA Scientific Missions such as SPECS or TetraStar and is hosted in GSFC’s Formation Flying Test Bed (FFTB). This paper will discuss the implementation and utilization of SDT within the AFRL’s Responsive Space Test Bed. | |
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| Paper Number RS4-2006-5005: On-orbit Calibration and Focus of Responsive Space Remote Sensing Payloads | |
| Thomas Chrien (Raytheon Space and Airborne Systems), Stephen Schiller (Raytheon Space and Airborne Systems) | |
| View/Download:Presentation | Paper | |
| Abstract: Radiometric, spectral, and spatial response performance and calibration knowledge requirements have been traditional cost drivers for remote sensing payloads. Performance has a direct relationship to the usefulness of the information product, including (1) bore-sight calibration in order to achieve geolocation accuracy, (2) optimization of focus to maximize spatial resolution, and (3) absolute spectral and radiometric calibration for effective atmospheric compensation. Meeting strict requirements prior to launch is problematic. Careful (and costly) compensation must be made for gravity effects, and thermal vacuum test conditions can only approximate on-orbit thermal environments. Furthermore, the trauma of launch and subsequent space contamination can invalidate a “perfect” pre-launch calibration. An alternative approach is to fine tune focus and calibration after the payload is on orbit using vicarious calibration techniques. This reduces cost and schedule by relieving the accuracy requirements and complexity of pre-launch calibration measurements. Cost / benefit rationale as well as conceptual approaches to pre-launch testing and on-orbit focus and vicarious calibration will be presented. | |
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| Paper Number RS4-2006-7001: Autonomous Operations for Responsive Spacecraft | |
| Jackie Reilly (a.i. Solutions), Terrance Yee (Microsat Systems) | |
| View/Download:Presentation | Paper | |
| Abstract: MicroSat Systems, Inc. (MSI) is currently supporting the Air Force Research Laboratory (AFRL) on several responsive space programs demonstrating tactically useful small satellites with autonomous operations. Contrary to previous autonomy efforts, these missions have autonomous on-board software which is specifically designed to allow end-users (or Warfighter), with no satellite expertise, to task the vehicle directly. This capability puts the Warfighter in direct control of a spacecraft changing several aspects of the original paradigm throughout the mission. The use of autonomy tools and modular software elements change the paradigms for traditional spacecraft operations. The change in the operational concept creates implications for overall project development timelines and for the end user in the field. Autonomous operations must be accounted for at the beginning of the requirements definition phase. While it is possible to upgrade existing systems after they are already designed, it is much more straightforward to initially design with the non-expert end-user in mind. This allows the appropriate selection of command and telemetry architecture to accommodate both the traditional expert end-user and a specialized interface for the Warfighter. Designing the Warfighter interface to be simple and minimalist from the beginning has profound impacts on the structure of the entire autonomous software. There is a major impact on spacecraft integration and testing throughout the development cycle and during on-orbit commissioning. There is significant synergy gained from coordinating the automation software (that performs ground testing), on-board testing (to verify state of health), and commissioning the spacecraft on orbit. By careful design of these capabilities, it is possible to not only save time but also increase the degree to which the ground team follows the “test like you fly” principle. The net impact of these changes is the following: shorten the time needed to deliver a working product to the end user, bring the end user concerns closer to the design team, change the focus of spacecraft utility design from a strategic asset to one which has short term tactical significance, and to place extremely powerful space assets in the hands of ground forces within minutes of request. This places a unique set of requirements on the software to be as easy to use as possible while also ensuring the safe operation of the spacecraft. Pairing the expertise of ground support and current autonomous ground system software with the expertise of spacecraft developers and current on-board software will help to design the on-board autonomous software that accomplishes this task. | |
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| Paper Number RS4-2006-7005: Time Critical Targeting Using Responsive Tactical Satellites | |
| John Carrico (Applied Defense Solutions), Travis Langster (Analytical Graphics, Inc.) | |
| View/Download:Presentation | Paper | |
| Abstract: A key enabler for responsive space is the capability to respond to unanticipated military needs in any geographical theater in a timely fashion. The CONOPS and utility for Unmanned Aerial Vehicles (UAVs) have become critical assets in current military operations. UAVs are deployed to specific theaters of ongoing operations. However, when an unexpected national security event of interest occurs, UAVs can not provide the same capability to any location on the globe within hours. However, the migration of UAV CONOPS to space could re-locate an asset to any geographical theater within hours. This paper will discuss the utility of pre-deployed tactical satellites to achieve national security responsive space through modeling & simulation techniques. Scenario — A high value target on the ground is identified via HUMINT sources. A military plan is required to nullify the target. The military plan requires time critical targeting information for pre-mission operations which include imagery and other intelligence data. There are no airborne sensors in-theater to support the mission within the desired timeline. The theater commander requests a capability of a tactical satellite with appropriate sensors be tasked to provide mission support to a forward unit. Concept — A concept of operations for this solution utilizes knowledge and information about the orbit of a rapid response satellite. An in-theater soldier utilizes an existing chat tool (Instant Messenger in the business world or Jabber in military intelligence operations) for computing the window of opportunity for the in-theater soldier to know precisely when an overhead responsive satellite would able to image or intercept signals from the target location. The same device used for the chat session receives imagery or other data via e-mail from the satellite as it passes overhead. Data is downloaded from responsive space satellite to handheld device with Time Critical Targeting information (e.g. imagery, target coordinates, etc…). Alternatively, the device could be outfitted to upload tasking commands of known targets for imagery or signals collection. The commercial software tool computes the precise time of collection opportunity and this start/stop time is uploaded in the tasking plan. Summary — The technology to compute precise collection opportunities and provide them in-realtime to in-theater soldiers is available today. Responsive space concepts can be achieved prior to launching new systems. By implementing unique modeling, simulation & analysis techniques with existing space platforms and within existing military, intelligence, and DoD infrastructures – tactical data from space platforms can be delivered. Responsive space concepts can have immediate military utility and can be enhanced with dedicated responsive space platforms. | |
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| Paper Number RS5-2007-2001: Partially Continuous Earth Coverage from a Responsive Space Constellation | |
| Scott C. Larrimore (USAF Institute for Defense Analyses) | |
| View/Download:Presentation | Paper | |
| Abstract: Over the past half century of spaceflight, national security space systems have evolved from principally serving strategic decision makers in national capitals to providing near real time information to tactical combat commanders. United States military leaders are searching for means to provide persistent coverage and sensor access to crisis locations. Small, responsive space platforms in low Earth orbit (LEO) may offer one answer to this persistency problem. Traditional constellations of small satellites have focused on providing continuous global or near-global coverage. These large, robust, and expensive constellations are deployed over many months or years. This paradigm is not suitable for providing responsive, tailored combat support to military theater forces. Alternatively, a small number of current LEO spacecraft provide short, fleeting accesses to a geographic region of interest, denying fielded forces the persistency they desire. These short, sporadic accesses are better suited for strategically oriented missions rather than tactical ones. One can, however, design a relatively small constellation of spacecraft to provide optimized, partially-continuous coverage for a given local geographic region or latitude band. Although this configuration will not provide continual coverage throughout the entire day, several hours of contiguous access is possible. The method consists of first analytically determining the inclination yielding the maximum access to a surface target location based upon a satellite’s altitude and sensor limitations. This inclination will normally be a little greater than the target’s latitude. Next, the orbital plane at this inclination is populated with spacecraft in a modified “streets of coverage” chain. The number of satellites in the chain depends upon the size of the area to be observed, satellite sensor constraints, and launch considerations. Continuous access times over several hours long are possible along with cumulative dwell times of 50% or more. Near continuous access of a local region is possible by populating a complementary second chain. Tailored constellations of this manner may provide the contextual structure tomorrow’s responsive spacecraft need to provide persistent overhead access deployed forces desire. This is just one of several new acquisition and operational paradigms needed to turn responsive space forces technologies into true tactical combat support enhancement capabilities. | |
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| Paper Number RS5-2007-2004: ORS HEO Constellations for Continuous Availability | |
| Brian L. Kantsiper (Johns Hopkins University Applied Physics Laboratory), Patrick A. Stadter (Johns Hopkins University Applied Physics Laboratory), John H. Benson (Johns Hopkins University Applied Physics Laboratory), Pamela L. Stewart (Johns Hopkins University Applied Physics Laboratory) | |
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| Abstract: Since 2005, the Integrated Systems Engineering Team (ISET), a working group drawn from industry, academia, and the national laboratories, has been developing standards for a standard spacecraft bus for Operationally Responsive Space (ORS) missions. As part of this effort, two highly elliptical orbits (HEO), with three and four hour periods, have been identified as options for missions which require long dwell-time over a particular region. Tacsat-4 will demonstrate the utility of one of these orbits to provide persistent communications. This analysis addresses the design of the constellation of the objective system. Walker-like constellations from three to eight satellites as well as the full range of arguments of perigee are considered for the critically inclined orbits. In addition, an alternate configuration using equatorial orbits is also examined. The impact of different approaches to handling times when multiple spacecraft are in view is discussed. For high latitudes, there is typically a one satellite penalty for using the lower orbit. This penalty becomes slightly more severe for lower latitudes, unless the equatorial configuration proves feasible, in which case five spacecraft in either orbit can provide continuous availability to low latitudes. | |
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| Paper Number RS5-2007-2005: Circular vs. Elliptical Orbits for Persistent Communications | |
| James R. Wertz (Microcosm) | |
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| Abstract: Responsive Communications missions typically require “persistent communications,” i.e., repeat coverage that lasts for an extended period or the entire day. LEO orbits cannot provide this coverage without a large number of satellites. The solution has traditionally been thought of as moderate altitude elliptical orbits, such as Magic or Cobra orbits. However, recent IR&D work by Microcosm suggests that this may be the wrong answer. This paper compares moderate altitude elliptical and circular orbits in terms of coverage, accessibility, flexibility, robustness, the environment, and impact on spacecraft design. The conclusion reached is that circular MEO orbits are a better choice than elliptical MEO orbits for supplementary or persistent communications. Broad rules for selecting the best orbit for specific communications applications are given. | |
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| Paper Number RS5-2007-3004: Responsive Space Programs for the Canadian Forces | |
| Donald Bedard (Defense Research and Development Canada), Aaron Spaans (Defense Research and Development Canada) | |
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| Abstract: Until quite recently, Canada’s Department of National Defence (DND) has not had the desire nor the resources to invest in indigenous military satellites mainly due to the high costs associated with conventional space programs. With current operational requirements rapidly evolving the long development time associated with conventional space programs also threatened to deliver an obsolete system by the time the satellite finally arrived on orbit. The emergence of increasingly capable micro-satellites in the last decade has made it such that space-based capabilities are now much more accessible than they were only a decade ago. For the past six years, DND’s research agency, Defence Research & Development Canada (DRDC) has investigated how micro-satellites could be used to provide the Canadian Forces (CF) with an appropriate, effective suite of technologies that best meets national and deployed operational needs. DRDC has developed a strategy that will allow mission concepts to be demonstrated at reduced risks for DND. This R&D strategy includes the development of operational exploitation plans which calls for the rapid integration of the new capability/ asset with existing capabilities. This paper will outline DRDC’s efforts towards developing a sustainable small satellite program. An overview of DRDC’s Space System Group (SSG) will be presented noting its R&D objectives and how it has defined the term “Responsive Space” to meet the requirements of the CF. This will also include a discussion on how the SSG has taken advantage of DRDC’s R&D strategy to establish micro-satellites as solid and viable options for current and future CF needs. The success of this strategy will be illustrated with the presentation of two technology demonstration missions that are currently in the implementation phase: the Near Earth Object Surveillance Satellite (NEOSSat) and the Maritime Monitoring and Messaging Micro-Satellite (M3MSat). | |
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| Paper Number RS5-2007-4001: ORS and TacSat Activities Including the Emerging ORS Enterprise | |
| Tom Doyne (OSD's Director of Defense Research and Engineering), Peter Wegner (Air Force Research Laboratory), Chris Olmedo (Army Space and Missile Defense Center), George Moretti (SMC Space Development Group), Mike Hurley (Naval Research Laboratory), Mark Johnson (Naval Research Laboratory), Tim Duffey (Naval Research Laboratory), Chris Huffine (Naval Research Laboratory) | |
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| Abstract: This paper assembles all the Joint Operationally Responsive Space (ORS) activities underway to clearly explain their purpose, status, and relationship to each other. Activities described include all TacSat experiments (1, 2, 3, 4, & 5), the ORS Bus Standards initiative, Virtual Mission Operation Center (VMOC) efforts, candidate launch vehicles’ status, operational experimentation, the ORS Payload Technology Initiative, and the formal ORS Enterprise emerging in 2007. This paper is the jointly written to properly include and describe all the ORS activities underway. This paper is the fifth in a series on TacSat and ORS; the previous RSC papers 2003-3001, 2004-5003, 2005-1006, 2006-4006 provide history and context for this paper. | |
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| Paper Number RS6-2008-1001: Numerical Optimization Study of LEO to LEO Aeroassisted Orbital Transfer for Small Satellites | |
| Arthur Scherich (University of Florida), Anil V. Rao (University of Florida), Skylar Cox (MicroSat Systems), Todd J. Mosher (MicroSat Systems) | |
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| Abstract: Operationally responsive space (ORS) is an area of growing interest to the U.S. space community. ORS refers to the ability to enhance capability, increase flexibility, and reduce execution time of operational spacecraft. A desirable capability for ORS is the development of spacecraft that can accomplish multiple distinct missions by having the ability to change its orbit. Designs for orbital transfer generally fall into one of two categories: all-propulsive transfers (where the orbit is changed completely using on-board fuel) or transfers that combine propulsive maneuvers with atmospheric flight maneuvers (where a portion of the orbital transfer is accomplished using propulsion while the remainder of the orbital transfer is accomplished using aerodynamic control via flight through the atmosphere). The latter category of orbital transfer is called aeroassisted orbital transfer. In the case of small satellites, the on-board fuel constraints will render all-propulsive maneuvers infeasible for many missions, thereby requiring the use of atmospheric flight maneuvers. Thus, it is important to study the problem of aeroassisted orbital transfer for ORS. Optimal aeroassisted orbital transfer for high-mass lifting bodies has been studied extensively (but never flown) over the past several decades. In these studies, several types of aeroassisted maneuvers, such as aerocruise with propulsive maneuvers and aeroglide without propulsive maneuvers, have been discussed. It has been found that the heating rate constraint is one of the key parameters in determining the performance of the aeroassisted orbital transfer (i.e. the sustainable heating rate directly affects the amount of inclination change that can be achieved by the aeroassisted maneuver) and the overall mission cost (i.e. the amount of fuel required for the mission). Due to the complexity of the atmospheric maneuvers and the need for performance (e.g. minimization of fuel), aeroassisted orbital transfer problems are often posed as optimal control problems. Moreover, because these optimal control problems cannot be solved analytically, it is necessary to obtain solutions using numerical methods. Numerical methods for solving optimal control problems fall into two general categories: indirect methods and direct methods. The merits of these two approaches will be discussed in this paper. In recent years a new class of direct methods that have shown promise in the numerical solution of optimal control problems are orthogonal collocation or pseudospectral methods. In an orthogonal collocation method, the state is approximated using a basis of polynomials. Several different orthogonal collocation methods exist including the Legendre pseudospectral method, the Chebyshev pseudospectral method, the Radau pseudospectral method, and the Gauss pseudospectral method. In this research we are interested in applying the Gauss pseudospectral method to the problem of low-Earth orbit (LEO) to LEO aeroassisted orbital transfer. In this paper accurate numerical solutions are presented to the problem of LEO to LEO aeroassisted orbital transfer for a small spacecraft with constraints on inclination change, heating rate, and total heat load is considered. The spacecraft is chosen to be of a size that can be launched on a modern day small launch vehicle (e.g. Falcon or Minotaur). Furthermore, we consider orbit transfers where the size, shape, and line of apsides of the terminal orbit are constrained. In particular, the constraint on the line of apsides makes it possible to locate the apogee of the orbit over a strategic point on the Earth for intelligence, surveillance, or reconnaissance (ISR) purposes. The aeroassisted orbital transfer problem is posed as a three-phase nonlinear optimal control problem and is solved using the software GPOCS9 which is a MATLAB® implementation of the aforementioned Gauss pseudospectral method. The optimal trajectories obtained in this study provide insight into the possibilities that these types of orbits could provide ORS missions in the future. | |
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| Paper Number RS6-2008-1003: ORS Mission Utility and Measures of Effectiveness | |
| James R. Wertz (Microcosm) | |
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| Abstract: One of the current elements of the ongoing Operationally Responsive Space (ORS) debate is whether and to what extent Responsive Space systems have sufficient utility to warrant the funding required to implement them. Traditionally, Measures of Effectives (MoEs) or Figures of Merit (FoMs) have been used to quantify the performance, which can then be compared to the cost of implementation. There have been some initial attempts to do this for ORS with both confusing and misleading results. This paper briefly summarizes the traditional space system mission utility analysis process in order to establish a framework for ORS utility analysis. We then define both general and specific ORS MoEs in the following broad categories: • Cost • Responsiveness • Performance • Risk • Flexibility • Mission Goals These are adjusted somewhat with respect to the traditional utility categories of performance, cost, risk, and schedule to reflect the fact that ORS missions are not duplicative of traditional missions, but complementary to them. For each category we define multiple ORS-relevant MoEs that measure performance in that area. We then use a representative ORS mission (responsive surveillance) to quantify the MoEs relevant to that mission. The goals of the paper are to provide a broad framework in which the utility of multiple ORS missions can be quantified, specific definitions of many of the relevant MoEs, and several specific examples of quantifying these MoEs to allow us to undertake a realistic, quantitative mission utility assessment of ORS cost vs. performance. ORS mission utility is particularly challenging in part because traditional missions have a constant, long-term purpose (e.g., provide 0.25-m resolution images of any point on the Earth’s surface within 48 hours), whereas ORS missions, by their very nature, are intended to respond to dynamic world events (e.g., provide appropriate coverage of hurricane Katrina or the recent flare-up in Kenya), and utility measures are inherently more challenging. Nonetheless, demonstrating and quantifying mission utility is key to funding ORS missions in an environment of severely constrained budgets and is critical to the future success of ORS. | |
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| Paper Number RS6-2008-1004: Distinguishing Attributes for the Operationally Responsive Space Paradigm | |
| Lauren Viscito (MIT), Matthew G. Richards (MIT), Adam M. Ross (MIT), Daniel E. Hastings (MIT) | |
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| Abstract: The value-centric perspective of responsive space places emphasis on meeting the needs of stakeholders in a timely and effective manner. While ongoing technology developments for spacecraft standardization and rapid launch as well as efforts to develop enabling concepts of operations, tactics, and procedures support the advancement of an operationally-responsive paradigm, little work has been completed to evaluate responsive architectures using value-based design methods. Attributes, decision maker-perceived metrics that measure how well a decision maker-defined objective is met, differ significantly between Operationally Responsive Space (ORS) and traditional “big space” paradigms. To address this gap and to draw explicit distinctions between ORS and “big space,” the attributes for both approaches are enumerated as a function of U.S. Air Force space mission areas. Five mission areas are evaluated in the analysis: (1) Intelligence, Surveillance, and Reconnaissance, (2) Position, Navigation, and Timing, (3) Communications, (4) Environmental Sensing, and (5) Missile Warning. The underlying methodology employed in this research is Multi-Attribute Tradespace Exploration (MATE), a conceptual design methodology that applies decision theory to model and simulation-based design. Decoupling the design from the need through tradespace exploration, MATE is both a solution-generating as well as a decision-making framework. The focus in this paper is on the front-end of the MATE process—eliciting preferences from system stakeholders, including decision makers that have significant influence over the allocation of resources in a development effort. These preferences are captured in multi-attribute utility functions. As a proxy for Air Force decision makers across mission areas, utility interviews were conducted with senior Air Force acquisition officers with decades of experience in national security space. In order to identify mission areas where a responsive architecture is more valuable, several steps are required. First, each of five Air Force mission areas is evaluated on the basis of several attributes, which vary between strategic and tactical applications. These attributes define the traditional measures of effectiveness for a given mission area. Second, ORS-specific attributes are elicited. The ORS paradigm has its own set of attributes, including timeliness, tactical control, and functional customization. These responsive attributes are proposed to be in a common set, existing across all of the mission areas. Third, comparison of traditional attributes sets are made to a joint set of traditional and responsive attributes, highlighting possible tensions and complements. Fourth, the impact of adding the responsive set to the overall design space is analyzed. Fifth, the paper discusses future work on using combined traditional and responsive attribute sets in dynamic tradespace analyses, enabling comparative evaluation of both ORS and “big space” architectures. The end goal of the research is to identify mission areas and operational contexts where either traditional space or ORS architectures are the most valuable to decision makers. | |
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| Paper Number RS6-2008-2001: Semi-Analytical Approach to Target Access in the Responsive Space Problem | |
| Prasenjit Sengupta (Texas A&M University), Srinivas R. Vadali (Texas A&M University), Kyle T. Alfried (Texas A&M University) | |
| View/Download:Presentation | Paper | |
| Abstract: The problem of orbit design for Responsive Space has received renewed interest due to several geopolitical and environmental reasons. Whereas low-cost satellites can easily be launched to cover regions on the Earth, their effectiveness can be maximized via optimization of their orbital parameters, resulting in reduction in the costs of launch, orbital maintenance, and orbital transfer. Satellite orbit design involves the study of several performance metrics. For example, time of coverage, percentage daylight coverage, and area of coverage due to successive passes over a target region, while accounting for sensor attributes, have been identified as metrics for several missions. This paper presents semi-analytical techniques that are useful for the evaluation of these metrics, with a reduction in computation time without compromising on the accuracy of the results. Algorithms are also presented for optimal impulsive maneuvers for station-keeping in the presence of environmental effects such as drag and terrestrial oblateness. | |
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| Paper Number RS6-2008-2002: Responsive Coverage Using Propellantless Satellites | |
| George E. Pollock (Purdue University), Joseph W. Gangestad (Purdue University), James M. Longuski (Purdue University) | |
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| Abstract: Traditional reconnaissance satellites, which are fixed in their orbits, are limited in responding to rapidly-evolving conditions on the battlefield. For example, typical satellites cannot alter their time of arrival over a current region of interest. Further, as one conflict subsides and another emerges, these satellites cannot change their inclination to cover different latitudes. Thus, to support the warfighter in dynamic battlespaces, significant on-orbit maneuvering capability may be highly desirable. In this paper, we introduce the Lorentz spacecraft, a near-term propellantless vehicle, which can change orbit inclination, arrival time, altitude, and other orbit characteristics. The spacecraft modulates an electrostatic charge that interacts with Earth’s magnetic field to induce a propulsive Lorentz force. Assuming a conventional satellite power system (e.g. solar panels or RTGs), this spacecraft has inexhaustible maneuvering capability. In a matter of days a satellite’s orbit can be reconfigured to provide coverage of new theaters, perform flyby inspection of foreign space assets, and evade foreign tracking. We demonstrate the feasibility of Lorentz spacecraft by 1) characterizing the orbit dynamics of a charged spacecraft in Earth’s magnetic field, 2) deriving control laws for a variety of responsive space applications, and 3) providing an overview of hardware considerations and development efforts. | |
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| Paper Number RS6-2008-2003: Angels and Demons – Cooperative and Non-Cooperative Formation Flying with Small Satellites | |
| Stuart Eves (Surrey Satellite Technology) | |
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| Abstract: The paper will discuss the challenges of both cooperative and non-cooperative formation flying using small satellites; operating either as guardians of larger satellites, or as space situation awareness collection assets. It is axiomatic that Angels or Demons will have different ballistic coefficients to the larger assets with which they are associated, and this leads to specific challenges for the small satellites in order to maintain station. The paper will discuss these challenges, and the potential propulsion system designs that would be appropriate in order to meet them; recognising that in different operational modes, the ideal inter-satellite separation distance could also be different. The paper will also address some specific design requirements that arise for these classes of formation flying systems. For example, in order to maintain their relative positions, both Angels and Demons will require collision avoidance systems to ensure that they do not inadvertently compromise the operation of the primary satellite asset. In the case of an Angel, where cooperative behaviour by the primary asset can probably be assumed, this is a somewhat more tractable problem than for a Demon. This is especially true if the concept of operations for a Demon requires not just a one-time rendezvous with a target, but also a period of continuous station maintenance with a manoeuvring target, and the situation is more complicated still if the Demon is also required to be stealthy. For some surveillance concepts, the relative position of the primary and secondary satellites will be important, (possibly to ensure appropriate lighting conditions for imaging systems, or to provide a line of sight between particular antennas), and clearly the laws of orbital dynamics will influence this over time. This introduces additional design constraints for the Angel or Demon, either of which will presumably wish to retain the option of communication to the Earth whilst performing its mission. The paper will thus conclude with recommendations concerning both the technical design and the concept of operations for these co-orbiting systems. | |
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| Paper Number RS6-2008-2004: Rapid Deployment of Proof-of-Concept Missions | |
| Jeffrey S. Cain (COM DEV Ltd.), Franz Newland (COM DEV Ltd.), F. Pranajaya (University of Toronto), R. Zee (University of Toronto) | |
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| Abstract: COM DEV Ltd. has recently completed two programs that made use of highly responsive space solutions to provide proof-of-concept data for an on¬going project dealing with the reception of Automatic Identification of Ships (AIS) signals from space. The first program, QuickAIS, was designed to fly a simple payload – essentially equivalent to a commercial-grade AIS receiver – with the purpose of determining what signals could be collected using existing, standard technology: a relatively simple question. This mission was based on the Rubin platform, with the payload connected directly to the upper stage of a Dnepr launcher. The launcher had been augmented to provide power and space-ground communications through the Orbcomm network. The mission payload was developed within 60 days, was launched in November 2007 and is currently in operation. The second program, Nanosatellite Tracking of Ships (NTS) was developed to answer a number of precise questions regarding the AIS signal environment from space. This mission, based on the UTIAS CanX2 bus, has been designed, developed and readied for flight in less than 6 months. The two missions varied in complexity and involved rapid development of payloads that met the mission objectives. The QuickAIS program was accomplished using a combination of modifying existing COTS products for flight and the addition of limited new RF components. The payload development for the NTS program was more comprehensive and involved the development of a new design using some of the components developed during QuickAIS and an entirely new digital back-end. The experiences gained by the COM DEV team and its partners while implementing these missions are elaborated upon in this paper. These cover the whole project lifecycle, from mission concept definition through delivery for launch. Both programs showed that it is possible to develop very reactive mission solutions to answer precise questions. This nonethe¬less depends on a number of prerequisites, such as a solid understanding of the mission objectives and a real-time interpretation of how they will be impacted by design decisions taken during the procurement phase. It is also imperative to start from an existing platform and/or payload design that meet the majority of the mission requirements, and have key hardware available at kick-off. The COM DEV team, starting from a hard contractual date for launch delivery, performed a number of innovative design trades, including difficult compromises on system performance whilst still meet¬ing mission objectives. This included accepting higher levels of risk, for example by using processes and parts with no flight heritage, where part alternatives based on supply availability were chosen in order to meet de¬velopment schedules. Testing was also reduced to address elements needed for mission data interpretation, or that could be fixed in the time available. These and other key elements that led to the successful execution of these programs are presented and explored in this paper. | |
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| Paper Number RS7-2009-2001: Rapidly Deployable Space Capabilities-Based Assessment — Approach and Status | |
| Maj. Ryan Pendleton (United States Air Force) | |
| View/Download:Presentation | Paper | |
| Abstract: At the request of the ORS Office and USSTRATCOM a capabilities-based assessment (CBA) is currently being conducted to define the requirements for Operationally Responsive Space (ORS) systems. This CBA, entitled the Rapidly Deployable Space CBA (RDS CBA), is being performed by a joint and interagency team led by AFSPC/A5V. It is designed to define key requirements for augmentation or reconstitution of "good enough to win" capabilities in the areas of space based intelligence, surveillance, and reconnaissance (ISR), space situational awareness (SSA), and satellite communications (SATCOM). In general, a CBA seeks to use the Dodd Joint Capabilities Integration Development System (JCIDS) to formally identify requirements and evaluation criteria for acquisition programs. The goal is to identify operational tasks, conditions and standards needed to accomplish objectives; assess the ability of current and programmed capabilities to accomplish the tasks identified (resulting in a list of capability gaps); and evaluate solutions from an operational perspective across the Doctrine, Organization, Training, Materiel, Leadership, Personnel, Facilities (DOTMLPF) spectrum. This paper will provide an update on the status of the scope and results of the RDS CBA. | |
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| Paper Number RS7-2009-2004: Implementation Challenges and Strategies for Responsive Space Architectures | |
| Matthew G. Richards (Massachusetts Institute of Technology), Zoe Szajnfarber (Massachusetts Institute of Technology), Annalisa L. Weigel (Massachusetts Institute of Technology) | |
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| Abstract: Current space acquisition programs are characterized by long-development cycles, cost overruns, and changing requirements. In an effort to match the time constants associated with space system development to the needs of users, operationally responsive space (ORS) architectures have been proposed. ORS missions envision pursuing short-term space capabilities tailored for emergent needs of Joint Combatant Commanders. Although ORS solutions may sacrifice performance on traditional measures of effectiveness with employment of smaller satellites and commercial-off-the-shelf (COTS) technology, ORS offers large potential improvements in matching the pace of change in user requirements with the timeliness of obtaining new capability on-orbit. While the purported benefits of ORS are well-documented in the literature, and technology development programs are already underway, there are several non-technical challenges that must be addressed as well. These challenges include aligning the economic incentives of stakeholders, integrating ORS into the current acquisition process, overcoming political inertia associated with legacy approaches, and ensuring that ORS capabilities complement existing architectures. Therefore, it is imperative that ORS development efforts take into account the full-spectrum of challenges. Based upon this framework of technical, economic, managerial, political, and architectural challenges, implementation strategies for ORS are developed. These strategies are illustrated using an example of fractionated spacecraft, which represents one potential architecture for achieving operationally responsive space. | |
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| Paper Number RS7-2009-3007: Redefining the Word “Responsive” in ORS | |
| Stuart Eves (SSTL) | |
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| Abstract: The word "responsive" has been used in a temporal sense to define the Tier 1, 2, and 3 capabilities envisaged for ORS. The paper will demonstrate how small, agile satellites with a variety of possible operational modes can be used to perform a variety of different surveillance and communications functions, thereby offering a different, flexible form of "responsiveness" to the military users of the system. Some of these agile operational modes are possible with larger satellites, but many rely on the compact design of small satellites to deliver capabilities that are simply not feasible with larger, more strategically oriented designs. | |
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