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2000

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Campus Connection, August 24, 2000, Vol. 2 No. 1, California State University, Monterey Bay Aug 2000

Campus Connection, August 24, 2000, Vol. 2 No. 1, California State University, Monterey Bay

Campus Connection

CSUMB Receives Almost $9 Million in State and Federal Grants -- Staff/Faculty Profile: Meet Bill Trumbo -- S.E.A. Lab Monterey Launches Maiden Voyage -- CSUMB and Fleet Numerical Sign Agreement -- NEWS BRIEFS -- Resource 25 Launched -- CSUMB Welcomes New Employees! -- PLANNER Web & BANNER Web

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Exponent, Vol. 32, No. 1, 2000-08-24, University Of Alabama In Huntsville Aug 2000

Exponent, Vol. 32, No. 1, 2000-08-24, University Of Alabama In Huntsville

2000

No abstract provided.

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'The Bible And Its Interpretation' Opens Ud Distinguished Speaker Season Aug 2000

'The Bible And Its Interpretation' Opens Ud Distinguished Speaker Season

News Releases

News release announces that the Rev. Peter J. Gomes will open the University of Dayton's 2000-2001 Distinguished Speaker Series season with a talk on "Transformed and Transforming Texts: The Bible and its Interpretation."

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Summer Mustang, August 24, 2000 Aug 2000

Summer Mustang, August 24, 2000

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.

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Campus Chronicle (Vol. 3, No. 2), Valparaiso University Aug 2000

Campus Chronicle (Vol. 3, No. 2), Valparaiso University

Campus Chronicle

No abstract provided.

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Panama Rejects Special Status For U.S. Military; Will Assist With Plan Colombia, Ladb Staff Aug 2000

Panama Rejects Special Status For U.S. Military; Will Assist With Plan Colombia, Ladb Staff

NotiCen

No abstract provided.

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August 24, 2000, The Daily Mississippian Aug 2000

August 24, 2000, The Daily Mississippian

Daily Mississippian (all digitized issues)

No abstract provided.

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Interactive Mission Design Web Site , John Leon, William Cutlip, Mark Hametz Aug 2000

Interactive Mission Design Web Site , John Leon, William Cutlip, Mark Hametz

Small Satellite Conference

The Access To Space (ATS) Group at NASA’s Goddard Space Flight Center (GSFC) supports the science and technology community by facilitating frequent and affordable opportunities for access to space. The ATS Group has developed an interactive Mission Design web site that provides both the information and the tools necessary to assist mission planners in selecting and planning their ride to space. The ATS web site was developed through core partnerships with other government agencies seeking similar tools for their mission planners. Key design features of the site include a searchable mission database and launch vehicle toolboxes. The mission database contains …

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Analysis Of Spectrum Band Sharing Between Cdma And Other Systems , Tarek Attia, Peter Sweeney, Martin Sweeting Aug 2000

Analysis Of Spectrum Band Sharing Between Cdma And Other Systems , Tarek Attia, Peter Sweeney, Martin Sweeting

Small Satellite Conference

Many mobile satellite systems have been proposed to employ Code Division Multiple Access (CDMA) technique at L/S band. These bands have been allocated to the mobile satellite services on a primary basis since 1992, in addition to the existing services. Therefore, the mobile satellite services will be subject to share spectrum with each other and with existing services. This paper discusses spectrum overlapping for two cases: i)- between a CDMA channel and narrowband signal channel; ii)- between CDMA channels sharing the same band. Analyses have been performed to increase the overall spectral efficiency in the frequency band, taking into account …

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Autonomous Control System For Precise Orbit Maintenance, Manop Aorpimai, Yoshi Hashida, Phil Palmer Aug 2000

Autonomous Control System For Precise Orbit Maintenance, Manop Aorpimai, Yoshi Hashida, Phil Palmer

Small Satellite Conference

In this paper, we describe a closed-loop autonomous control system that enables orbit operations to be performed without the need of any ground segment. The growing availability of GPS receivers on satellites provides an excellent means for autonomous orbit determination and our work builds upon previous work on orbit determination algorithms developed here at Surrey. The orbit is described using a set of epicycle parameters which provide an analytic model of LEO orbits. The parameters in this model are estimated onboard the satellite using a Kalman filter. We describe an enhancement to this software which provides both control as well …

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Autonomous Operations Experiments For The Distributed Emerald Nanosatellite Mission , Christopher Kitts, Michael Swartwout Aug 2000

Autonomous Operations Experiments For The Distributed Emerald Nanosatellite Mission , Christopher Kitts, Michael Swartwout

Small Satellite Conference

Distributed space systems are often cited as a means of enabling vast performance increases ranging from enhanced mission capabilities to increased system flexibility. Achieving this vision, however, will require radical advances in the automated control of these multi-satellite systems. To explore this challenge, Santa Clara University and Stanford University have initiated development of a simple, low cost, two-satellite mission known as Emerald. The Emerald mission includes several experiments involving the autonomous operation of distributed space systems. First, “low-level” inter-satellite navigation techniques will be explored. Second, “high-level” multi-satellite health and command management functions will be demonstrated. Due to operational considerations and …

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Infrastructure For Internet-Based Operations, James Cutler, Gregory Hutchins, Christopher Kitts, Robert Twiggs Aug 2000

Infrastructure For Internet-Based Operations, James Cutler, Gregory Hutchins, Christopher Kitts, Robert Twiggs

Small Satellite Conference

Global access to remote systems is becoming a reality through advances in the Internet. Applied to spacecraft operations, this provides the opportunity for spacecraft operators to access remote system resources from any location with Internet access. As part of its space operations research, Stanford University's Space Systems Development Laboratory (SSDL) is exploring the ability of Internet based operations to improve the cost effectiveness of space mission operation. It is developing a ground station control system to provide computer assisted console control, remote operation, and software agent-based autonomous control. Known as Mercury, the system has been implemented on SSDL's OSCAR-class amateur …

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Status Of Chips: A Nasa University Explorer Astronomy Mission, Will Marchant, Ellen Riddle Taylor Aug 2000

Status Of Chips: A Nasa University Explorer Astronomy Mission, Will Marchant, Ellen Riddle Taylor

Small Satellite Conference

In the age of "Faster, Better, Cheaper", NASA's Goddard Space Flight Center has been looking for a way to implement university based world class science missions for significantly less money. The University Explorer (UNEX) program is the result. UNEX missions are designed for rapid turnaround with fixed budgets in the $10 million US dollar range. The CHIPS project was selected in 1998. The CHIPS mission has passed the Concept Study and will be having the Confirmation Review in August 2000. Many lessons have already been learned from the CHIPS UNEX project. This paper will discuss the early issues surrounding the …

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Effects Of Networking Configurations On Space Channel Throughput, Stephen Horan, Ru-Hai Wang Aug 2000

Effects Of Networking Configurations On Space Channel Throughput, Stephen Horan, Ru-Hai Wang

Small Satellite Conference

The throughput results for file transfers using file sizes ranging from 1 Kbyte through 1 Mbyte using both the standard TCP/IP and SCPS protocol stacks are reported here. The file transfers are performed at a range of balanced and unbalanced link speeds and channel error rates. The host computers used in the simulations are using standard Linux operating system configurations on PC platforms. The PPP is used as a framing protocol to support communications between the computers. The file-transfer throughput results will show the effects of link configuration and channel error rate on the necessary time to transfer a file. …

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Cubesat: A New Generation Of Picosatellite For Education And Industry Low-Cost Space Experimentation , Hank Heidt, Jordi Puig-Suari, Augustus Moore, Shinichi Nakasuka, Robert Twiggs Aug 2000

Cubesat: A New Generation Of Picosatellite For Education And Industry Low-Cost Space Experimentation , Hank Heidt, Jordi Puig-Suari, Augustus Moore, Shinichi Nakasuka, Robert Twiggs

Small Satellite Conference

The launch and deployment of picosatellites from the Stanford University OPAL microsatellite in February 2000 demonstrate the feasibility and practicability of a new age of space experimentation. Two of the six picosatellites deployed from OPAL were built by The Aerospace Corporation in El Segundo, CA and demonstrated new space testing of MEMS RF switches and intersatellite and ground communication with low power wireless radios. These picosatellites weighting less than one kilogram with dimensions of 4x3x1 inch were built as test platforms for DARPA and were constructed and delivered for flight in less than nine months. From this experience, a new …

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The Jawsat Mission: Final Report And Lessons Learned , J. Smith, D. Richards, M. Wood, G. Sharp, W. Clapp Aug 2000

The Jawsat Mission: Final Report And Lessons Learned , J. Smith, D. Richards, M. Wood, G. Sharp, W. Clapp

Small Satellite Conference

One Stop Satellite Solutions and the Center for Aerospace Technology recently completed the JAWSAT mission. This was the first flight of the Minotaur launch vehicle and the first time eleven separate micro and pico satellites were placed into orbit with one launch. The JAWSAT project required both new technical designs as well as new programmatic ways of conducting a space mission. Main stream, large satellite, methods were not adequate. Technical lessons learned on this project range from new techniques in versatile, low-cost, structural design to a reasonable method of qualifying commercial off-theshelf electronic components. New methods of final integration and …

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Internet Access To Spacecraft, James Rash, Ron Parise, Keith Hogie, Ed Criscuolo, Jim Langston, Chris Jackson, Harold Price Aug 2000

Internet Access To Spacecraft, James Rash, Ron Parise, Keith Hogie, Ed Criscuolo, Jim Langston, Chris Jackson, Harold Price

Small Satellite Conference

The Operating Missions as Nodes on the Internet (OMNI) project at NASA's Goddard Space flight Center (GSFC), is demonstrating the use of standard Internet protocols for spacecraft communication systems. This year, demonstrations of Internet access to a flying spacecraft have been performed with the UoSAT-12 spacecraft owned and operated by Surrey Satellite Technology Ltd. (SSTL). Previously, demonstrations were performed using a ground satellite simulator and NASA's Tracking and Data Relay Satellite System (TDRSS). These activities are part of NASA's Space Operations Management Office (SOMO) Technology Program. The work is focused on defining the communication architecture for future NASA missions to …

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Asusat1: Low-Cost, Student-Designed Nanosatellite, Assi Friedman, Brian Underhill, Shea Ferring, Christian Lenz, Joel Rademacher, Helen Reed Aug 2000

Asusat1: Low-Cost, Student-Designed Nanosatellite, Assi Friedman, Brian Underhill, Shea Ferring, Christian Lenz, Joel Rademacher, Helen Reed

Small Satellite Conference

On January 27, 2000 (UTC) ASUSat1 was launched into space onboard Orbital Sciences’ Minotaur rocket. The launch was the culmination of six years of effort by over 400 students. ASUSat1 is an innovative nanosatellite bringing new concepts for low-power, low-mass, highly constrained designs. Its primary mission was earth imaging, with several secondary missions including orbit determination, amateur-radio communications, passive stabilization techniques, attitude detection, and composite-material research. Following the successful launch and deployment of ASUSat1, the satellite operated for 14 hours. In spite of this, the team collected useful data from the satellite, and verified many of the design concepts incorporated …

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Recovery Of The Wide-Field Infrared Explorer Spacecraft, David Everett, Thomas Correll, Scott Schick, Kimberly Brown Aug 2000

Recovery Of The Wide-Field Infrared Explorer Spacecraft, David Everett, Thomas Correll, Scott Schick, Kimberly Brown

Small Satellite Conference

The Wide Field Infrared Explorer was developed to perform astronomy using a cryogenically cooled infrared telescope. Shortly after launch, rapid venting of the cryogen, caused by an untimely cover removal, sent the spacecraft into an uncontrollable spin which exceeded 60 revolutions per minute. Over the next week, the WIRE team developed a plan and successfully executed the procedures necessary to de-spin the spacecraft and gain attitude control, but the cryogen for cooling the instrument was depleted. The recovery of the spacecraft enabled a thorough checkout of most of the subsystems, including the validation of several new technologies. Although the primary …

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Real-Time Attitude And Orbit Control System Of A Small Leo Satellite With Parallel-Processing Approach In A Ground Station, Roger Johnson, Sanjay Jayaram, Lei Sun, Chan Ho Ham Aug 2000

Real-Time Attitude And Orbit Control System Of A Small Leo Satellite With Parallel-Processing Approach In A Ground Station, Roger Johnson, Sanjay Jayaram, Lei Sun, Chan Ho Ham

Small Satellite Conference

A Real-time Attitude and Orbit Control System (AOCS) using a parallel processing approach will be implemented using a Satellite Ground Control Station (SGCS). With this approach, the satellite will collect platform (attitude reference) and payload measurements (at 1Hz) over several orbits and down-link to the SGCS (at 5 KHz) where the real-time filtering, fault detection, diagnosis and corrective (if needed) control is generated. The control commands are up-linked to the satellite before losing telemetry lock. A substantial reduction in on-board computation can provide a cheaper and a higher reliable AOCS. In the proposed scheme, an advanced real-time estimation and control …

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Aeroastro’S X-Band Transponder – Meeting The Communication Needs Of Tomorrow’S Small Spacecraft , Eric Aamot, Ray Zenick, Kimberly Kohlhepp Aug 2000

Aeroastro’S X-Band Transponder – Meeting The Communication Needs Of Tomorrow’S Small Spacecraft , Eric Aamot, Ray Zenick, Kimberly Kohlhepp

Small Satellite Conference

This paper will discuss a number of technologies and design philosophies leveraged from commercial industry that AeroAstro has applied to the development of a new spacecraft communications subsystem. Although there has been a recent push toward reducing spacecraft mass and cost, there is no commercially available communications equipment that will significantly contribute to that reduction. While spacecraft mass has dropped more than an order of magnitude in the past ten years, radios have not followed this trend. AeroAstro is developing a highly integrated, power-efficient, low operating voltage X-Band telemetry transponder for small satellite applications. This design leverages emerging technology from …

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Effects Of A Distributed Computing Architecture On The Emerald Nanosatellite Development Process , Julie Townsend, Bryan Palmintier, Eric Allison Aug 2000

Effects Of A Distributed Computing Architecture On The Emerald Nanosatellite Development Process , Julie Townsend, Bryan Palmintier, Eric Allison

Small Satellite Conference

Building satellites with greater capabilities on shorter timelines requires changes in development approach. Relative to previous satellite projects in Stanford’s Space Systems Development Laboratory (SSDL), the Emerald Nanosatellite system is highly complex. Its mission requires numerous experiments and relatively sophisticated subsystem capabilities. To develop this system on a short two-year timeline required a new development approach to simplify system integration. As a result, the Emerald development team adopted a modular distributed computing architecture. While this decision imposed many changes on Emerald’s design process, the benefits of the distributed architecture for system integration and testing justified its selection. This approach has …

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The Kyushu/Us Experimental Satellite Tether (Quest) Mission, A Small Satellite To Test And Validate Spacecraft Tether Deployment And Operations, Johan Carlson, Yosuke Nakamura Aug 2000

The Kyushu/Us Experimental Satellite Tether (Quest) Mission, A Small Satellite To Test And Validate Spacecraft Tether Deployment And Operations, Johan Carlson, Yosuke Nakamura

Small Satellite Conference

In recent years, an increased effort to design, build, and operate small satellites has taken place in universities and laboratories all over the world. These microsatellites provide numerous flight opportunities for science experiments at a fraction of the cost of larger traditional missions. In addition, there has been an increasing trend towards international cooperation on space projects. From the International Space Station to joint commercial ventures, the future of space progress will be shared by countries around the world. Tomorrow’s engineers must prepare for this challenge. This paper provides an overview of the Kyushu/US Experimental Satellite Tether (QUEST) mission, a …

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The Design And Feasibility Study Of Nanosatellite Structures For Current And Future Fsi Micromissions , Badrinarayan Shirgur, Derek Shannon Aug 2000

The Design And Feasibility Study Of Nanosatellite Structures For Current And Future Fsi Micromissions , Badrinarayan Shirgur, Derek Shannon

Small Satellite Conference

To support focused science and engineering micromissions, spacecraft bus designs should minimize mass and maximize design flexibility without reducing capability. This requires a highly efficient spacecraft structure to maintain the required stiffness with a minimal mass. In the following presentation, two design approaches are evaluated for the structure of the Florida Space Institute’s nanosatellite bus. One design uses sandwich construction exclusively, representing the current level of spacecraft structures. The other design uses a cast aluminum primary structure, which is a new approach for nanosats. Based on the evaluation of these two structures, the cast aluminum design is selected for FSI’s …

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Opal: Smaller, Simpler, And Just Plain Luckier, James Cutler, Greg Hutchins Aug 2000

Opal: Smaller, Simpler, And Just Plain Luckier, James Cutler, Greg Hutchins

Small Satellite Conference

On January 26, 2000 at 7:03PM PST, Stanford University’s first student built satellite, OPAL – the Orbiting Picosatellite Automated Launcher, roared into space on a modified Minuteman II missile. Students from the Space Systems Development Laboratory spent four years designing, fabricating, and testing the OPAL satellite in preparation for the launch. OPAL’s primary mission objectives were to explore a new mothership/daughtership mission architecture for distributed sensing, to characterize an off-the-shelf magnetometer, and to characterize a suite of off-the-shelf accelerometers. Six DARPA sponsored daughterships, also known as picosatellites, were deployed from OPAL. They were built by The Aerospace Corporation, Santa Clara …

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Command And Data Handling Subsystem Design For The Ionospheric Observation Nanosatellite Formation (Ion-F) , John Jensen Aug 2000

Command And Data Handling Subsystem Design For The Ionospheric Observation Nanosatellite Formation (Ion-F) , John Jensen

Small Satellite Conference

This paper describes the approach taken by the ION-F student team in designing a common Command and Data Handling (C&DH) subsystem for three different nanosatellites. It outlines the requirements of the satellites and reasons behind the decision to develop a custom board. The design is based upon industrial-grade components and centered on a Hitachi SuperH RISC Processor. The C&DH subsystem contains a 16 MB telemetry buffer, a digital and analog interface subsystem, and a DMA-oriented CMOS camera framebuffer. Students are fabricating these boards with the assistance of Space Dynamics Laboratory at Utah State University. This design will be flown by …

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Digital Cmos Cameras For Attitude Determination, David Meller, Prapat Sripruetkiat, Kristin Makovec Aug 2000

Digital Cmos Cameras For Attitude Determination, David Meller, Prapat Sripruetkiat, Kristin Makovec

Small Satellite Conference

The Ionospheric Observation Nanosatellite Formation (ION-F) satellite cluster consists of three individual spacecraft, which are being developed by the University of Washington (UW), Utah State University (USU), and Virginia Polytechnic Institute and State University (VT). The satellites will demonstrate formation flying and distributed satellite capabilities. A novel component of the Attitude Determination System (ADS) for each satellite is use of low-power, low-mass, inexpensive CMOS cameras for Sun and Earth horizon sensing. This paper describes a candidate camera set of specifications, the configuration of cameras on each ION-F satellite and a sensor fusion scheme for the ADS. Several algorithms for nadir …

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Gps Micro Navigation And Communication System For Clusters Of Micro And Nanosatellites , Ray Zenick, Kimberly Kohlhepp Aug 2000

Gps Micro Navigation And Communication System For Clusters Of Micro And Nanosatellites , Ray Zenick, Kimberly Kohlhepp

Small Satellite Conference

Formation flying will quickly revolutionize the way science, remote sensing and surveillance missions are performed in space, enabling a whole new range of applications for small satellites. Currently, there are numerous missions in the planning stages involving formation flying of a constellation of micro or nanosatellites. However, to truly achieve the goals of these formation-flying missions, an accurate means of relative ranging, determining time and position measurements, inter-satellite communications, and controlling the formation states is becoming critical. Today, while there are very expensive products available for positioning and attitude determination, none of them are capable of meeting the precise positioning …

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Lightweight Optical Wavelength Communications Without A Laser In Space, D.A. Hazzard, J.A. Maccannell, G. Lee, C.D. Garrett, J.A. Payne, N. Dahlstrom, T.M. Shay Aug 2000

Lightweight Optical Wavelength Communications Without A Laser In Space, D.A. Hazzard, J.A. Maccannell, G. Lee, C.D. Garrett, J.A. Payne, N. Dahlstrom, T.M. Shay

Small Satellite Conference

We will present a model for an earth-to-low-earthorbit optical communications system. The system modeled herein is designed to offer a very lightweight, low power consumption, low data rate communications link from LEO satellites. A novel architecture for a free-space optical communications link is presented and analyzed. For the first time, a method that offers full-duplex communications on a single beam is presented. In addition, a novel data format for free-space optical communications is presented. In this system, both the laser and the downlink receiver are located on the ground. The optical elements located on the spacecraft are a simple uplink …

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A Fast Prediction Algorithm Of Satellite Passes, P.L. Palmer, Yan Mai Aug 2000

A Fast Prediction Algorithm Of Satellite Passes, P.L. Palmer, Yan Mai

Small Satellite Conference

Low cost, fast access and multi-functional small satellites are being increasingly used to provide and exchange information for a wide variety of professions. They are particularly useful, for example, as a resource in very remote areas where they can provide useful information such as to rescue teams for changing conditions in a disaster zone and monitoring the sea state to warn approaching shipping. Unlike terrestrial communication systems, the receiver/transmitter in these di_erent application areas needs to be powered on and contact to specialised satellites to exchange data at speci_c time rather than consuming valuable power at all the time. This, …

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