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A Design Template For Gas Satellite Payloads, Daniel Sakoda Sep 1988

A Design Template For Gas Satellite Payloads, Daniel Sakoda

Small Satellite Conference

The Naval Postgraduate School has designed a small, low cost, general purpose satellite bus, ORION. An investigation of the structural requirements has been done for ORION as an extended Get Away Special (GAS) canister payload. The structure must be able to withstand the design limit load of 6.0 g's acceleration in ± X and ± Y, and a limit load of 10.0 g's in the ± Z. The structure must also have modal vibration greater than 35 Hz. A finite element analysis in linear bending considers an aluminum stiffened cylinder with two equipment plates and a top plate. Considerable weight …

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The Development Of An Attitude Sensing System For Small Satellites, Wedad Abdou, Sawat Tantiphanwadi Sep 1988

The Development Of An Attitude Sensing System For Small Satellites, Wedad Abdou, Sawat Tantiphanwadi

Small Satellite Conference

This paper describes the attitude sensing system developed by Globesat, Inc. for its gravity-gradient-stabilized satellites. Compactness, low cost, low power, and high performance were the main considerations of the system design. The sensor is based on a commercial CCD video camera for imaging the sun and the horizon. The images are digitized by a frame grabber and then processed for attitude computation. The system has a field of view of 90 X 360 and can determine attitude to 10 or better. Using the sun and nadir vectors as references, the orientation of the satellite with respect to the Earth is …

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Packet Store-And-Forward Communications Satellites For Relief And Development, Gary Garriott Sep 1988

Packet Store-And-Forward Communications Satellites For Relief And Development, Gary Garriott

Small Satellite Conference

The early history of proposed small satellites in low earth orbit using store-and-forward digital technology for humanitarian relief and development work is reviewed. A description of the current status of the PACSAT project being developed jointly by SST Ltd and VITA is is provided. The need to decrease the turnaround period of time-dependent technical information to and from isolated regions of the world is described, as well as limitations to project success when the right information is not available at the right time. Major PACSAT applications areas in relief and development are presented, and a functional description of several tiers …

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Design And Development Of A Standardized Electronics Box, David Spencer Sep 1988

Design And Development Of A Standardized Electronics Box, David Spencer

Small Satellite Conference

The Naval Research Laboratory (NRL), in conjunction with the McDonnell Douglas Astronautics Company (MDAC), has developed a standardized electronics box that provides a simple, cost-effective structure to house various digital and analog electronic circuitry. The standard electronics box design adheres to the Lightsat principles of simple and inexpensive articles which can reliably perform various missions. This standard electronics housing design reduces repetitive design and testing costs; specifically, shock and vibration qualification testing, venting, fracture, and thermal analyses, and mass properties determination. The simple box design allows for ease of manufacture and a direct path for conductive thermal dissipation, and flexibility …

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Sensor Deployment Mechanism For Surfer Satellite, Robert Dill, James Flom, Donald Gibbons Sep 1988

Sensor Deployment Mechanism For Surfer Satellite, Robert Dill, James Flom, Donald Gibbons

Small Satellite Conference

SURFER, the Stanford University Radio Frequency Emissions Receiver, is a small, free flying, spin stabilized satellite. It will take measurements of the earth’s ionosphere during the joint US/Italian Shuttle tether experiment. To obtain these measurements several sensors must be extended from the satellite to Specified positions. This will increase the resolution of the instruments and decrease the electromagnetic interference from the satellite electronics. The primary requirements for the deployment mechanism are: 1) The sensors must be positioned at least 60 inches from the satellite with ± 5% on the known deployed length and a ±1 degree tolerance on the known …

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A Framework For Analyzing The Market And Supporting Infrastructure For Small Satellites And Associated Systems, Stephen Morgan Sep 1988

A Framework For Analyzing The Market And Supporting Infrastructure For Small Satellites And Associated Systems, Stephen Morgan

Small Satellite Conference

A comprehensive, conceptual framework within which space programs, projects, and activities can be analyzed is presented. This framework consists of a number of largely functional dimensions. Most important is the division of space-based and space-oriented activity into two major segments: the space infrastructure, and space-derived products and services. The space infrastructure includes the various functions and devices which support space-oriented activity, including launch vehicles, payload and vehicle processing facilities plus those organizational and technological elements which support space-oriented activity, including the institutional support base. Space-derived products and services are those products and services which can only be produced within the …

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Uogas - A Get Away Special Satellite With Orbit-Raising Capability, Ralph Lorenz Sep 1988

Uogas - A Get Away Special Satellite With Orbit-Raising Capability, Ralph Lorenz

Small Satellite Conference

The low cost of satellite deployment from Shuttle GAS canister makes it an attractive launch option. However, the low deployment altitude severely constrains lifetime so the UoGAS (University of Surrey Get Away Special) spacecraft will incorporate a propulsion system. Lifetime extension methods are considered and a start-of-mission orbit-raising manoeuvre is selected. An orbit dynamics simulation method (taking into account the atmospheric drag) is discussed and results presented. Mission profiles, propulsion systems (including colloid, resistojet and cold gas thrusters, as well as a novel hybrid bipropellant combination) and stabilisation options are discussed: an aerodynamically stabilised vehicle with a resistojet propulsion system …

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International Small Satellite Organization; Connecting The Small Space Systems Community, R. Fleeter Sep 1988

International Small Satellite Organization; Connecting The Small Space Systems Community, R. Fleeter

Small Satellite Conference

ISSO (International Small Satellite Organization) connects the diverse members of the low cost space systems community. The bimonthly ISSO newsletter, related ISSO activities, membership and membership services are described. The role of ISSO in the emerging small satellite/launcher industry and ISSO plans for 1989 are discussed. ISSO’s first 18 months and some publication highlights are reviewed.

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Nonvolatile Solid State Data Recorder For Space Applications, Russell Averill Sep 1988

Nonvolatile Solid State Data Recorder For Space Applications, Russell Averill

Small Satellite Conference

Solid state data recorders provide numerous advantages over reel-to-reel tape recorders. Having no moving pans, they offer great reliability and do not produce troublesome reaction torques as compared to mechanical recorders. The Naval Postgraduate School has designed and built a solid state magnetic bubble memory data recorder for use on board a satellite. This recorder is based on a modular concept. The basic configuration consists of a back plane, power supply card, a controller card, a recorder interface card, a system interface card, and a selectable number of memory cards, containing four Mbytes each.

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A Small Ion Propelled Spacecraft For Near Earth Experiments, S. Field, K.A. Ryden, P. Truscot, N.C. Wallace Sep 1988

A Small Ion Propelled Spacecraft For Near Earth Experiments, S. Field, K.A. Ryden, P. Truscot, N.C. Wallace

Small Satellite Conference

It has become increasingly apparent that designers of today's large and complex spacecraft are reluctant to adopt many new and innovative technologies due to the lack of in-orbit operational experience with these devices, a particular example being ion propulsion. The reasons for this are understandable but as a consequence many new ideas are caught in a 'chicken and egg' situation where they will not be flown until they have been and shown to work reliably. A study has been carried out in an attempt to provide a simple, low cost spacecraft that can be launched from almost any vehicle into …

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Active Magnetic Control System For Gravity Gradient Stabilized Spacecraft, Francois Martel, Parimal Pal, Mark Psiaki Sep 1988

Active Magnetic Control System For Gravity Gradient Stabilized Spacecraft, Francois Martel, Parimal Pal, Mark Psiaki

Small Satellite Conference

Active magnetic control is studied as a means to improve the capabilities and performance of gravity gradient stabilized spacecraft. Active magnetic control eliminates the need for a passive damper and can reduce significantly the costs and complexity of other functional parts of the spacecraft. The system under study includes three magnetic torquers, one three-axis magnetometer, and a control processor. It does not require any moving parts, and provides for rapid libration damping, tighter stabilization and active control of the yaw angle. Control algorithms are defined. Results of the analysis of the control laws and computer simulations, including high-order models of …

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Preliminary Design And Concept Of Operations For A Small Tactical Imaging Satellite, Neal Miller, Larry Chizek Sep 1988

Preliminary Design And Concept Of Operations For A Small Tactical Imaging Satellite, Neal Miller, Larry Chizek

Small Satellite Conference

Tactical commanders could use a reconnaissance satellite which is survivable, flexible in operations, and able to provide real time direct data of high quality imagery. By design, the imaging satellite would be inexpensive and mutually beneficial to all the armed services. The imaging satellite is solar powered and 3 axis stabilized. A constellation of satellites in sun synchronous orbits will provide near worldwide coverage with revisit times of 90 minutes. Command and control will come from a single field unit, although many units may have receive capability. The satellite could be used during times of crisis or stored for future …

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Payload Positioning System For Gravity Gradient Satellite, M. Holliday, D. Pancratz, E. Park, D.B. Putnam Sep 1988

Payload Positioning System For Gravity Gradient Satellite, M. Holliday, D. Pancratz, E. Park, D.B. Putnam

Small Satellite Conference

Many current satellites rely on active control systems to maintain attitude. Passively controlled gravity gradient satellites cost less and are more reliable, but have difficulty accommodating independently moving payloads such as pointable telescopes. To eliminate these difficulties, use of a counter rotating inertia is proposed to negate payload induced transient instabilities. Counter rotating inertias have been used before with limited success due to residual torque/momentum. In gravity gradient satellites, this is absorbed by the gravity gradient restoring torques. A single axis (of a three axis) demonstration gimbal using a bifilar pendulum with PC controlled servo feedback loop and simulated pointable …

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On-Orbit Annealing Of Satellite Solar Panels, Sherif Michael, R.S. Sommers Sep 1988

On-Orbit Annealing Of Satellite Solar Panels, Sherif Michael, R.S. Sommers

Small Satellite Conference

An approach to extend the life of orbiting satellites is presented. Since output power of spacecraft solar panels plays a major role in determining the end of life of the satellite, any attempt to recover any of this lost power would be very attractive. The goal of this research was to investigate the possibility of annealing radiation damaged solar panels under conditions that would be feasible to apply in orbiting spacecraft. Preliminary data of a technique called forward biased current annealing of GaAs cells is presented and shows promising results at a moderate temperature. An autonomous microprocessor controlled experiment to …

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Operation Of A Small Tethered Payload, Peter Banks, Roger Williamson, Thomas Vaneck, Burt Lee, Eric Stoneking Sep 1988

Operation Of A Small Tethered Payload, Peter Banks, Roger Williamson, Thomas Vaneck, Burt Lee, Eric Stoneking

Small Satellite Conference

This paper presents results of a study currently being performed at Stanford University sponsored by NASA/Goddard Space Station Small Attached Payloads. The use of tethers as a means of dynamic isolation for small attached payloads shows promise in reducing orbital maneuvering vehicle requirements to service co-orbiting facilities while still providing a stable contamination-free platform for precision pointing instruments. Thethers may also be used as a means of deorbiting small sample return vehicles. These return vehicles might be dedicated small experiment carriers for a specific mission and require little manned interaction, or they might be loaded with experimental samples for de-orbit …

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Modeling Atmospheric And Solar Radiation Pressure Effects On The Attitude Dynamics Of Small Satellites, Thomas Vaneck Sep 1988

Modeling Atmospheric And Solar Radiation Pressure Effects On The Attitude Dynamics Of Small Satellites, Thomas Vaneck

Small Satellite Conference

Because of the current interest in: 1) Small inexpensive LEO satellites, 2) Small STS/SS tethered satellites, and 3) Precision pointing spacecraft used in celestial and terrestrial observations, there is a renewed interest in predicting the effects of solar and atmospheric pressures on these vehicles. To date the majority of published work has been restricted to simple, well defined vehicle geometries. The investigation of other geometries requires a considerable effort to redefine and implement the new configuration. Since it is difficult, if not impossible, to find a near optimal spacecraft geometry analytically, the designer must choose a particular configuration and limit …

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A Feasibility Study For A Remotely Controlled, Low-Power- Consumption Scanning Electron Microscope Suitable For Space Applications, John Chidester, Lynn Chidester Sep 1988

A Feasibility Study For A Remotely Controlled, Low-Power- Consumption Scanning Electron Microscope Suitable For Space Applications, John Chidester, Lynn Chidester

Small Satellite Conference

Experiments and instruments for operation in and on small satellites are constrained by the volume, weight, power, and ruggedness requirements of the satellite design and structure. It is anticipated that increasing numbers of "laboratory" style experiments will be performed in space. An application of current interest is the in-space observation of material surfaces exposed to the space environment. One such instrument for possible small satellite flight operational use, is a scanning electron microscope (SEM). The design factors and parameters of such an SEM, as well as the trade-offs and instrument limitations, will be discussed. The electronic control and image relay …

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Observations Of Single-Event Memory Upsets On The Uosat-2 Satellite, Jeff Ward Sep 1988

Observations Of Single-Event Memory Upsets On The Uosat-2 Satellite, Jeff Ward

Small Satellite Conference

This paper describes observations of single-event memory upsets in the UoSAT-2 satellite Digital Communications Experiment. Two years of SEU observations for Harris 6564 memories are included, presented both as error rate statistics and as a map of satellite orbital location at the time of error occurrence. The results presented here are the preliminary observations in a long-term single-event upset study funded by ESA-ESTEC.

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Space - Radiation Qualification Of A Microprocessor Implemented For The Intel 80186, R.H. Maurer, J.D. Kinnison, B.M. Romenesko, B.G. Carkhuff, R.B. King Sep 1988

Space - Radiation Qualification Of A Microprocessor Implemented For The Intel 80186, R.H. Maurer, J.D. Kinnison, B.M. Romenesko, B.G. Carkhuff, R.B. King

Small Satellite Conference

The Intel 80186 sixteen-bit microprocessor is an example of a high performance device (8 MHz) needed to carry out advanced experimentation on Low Earth Orbit missions. However, this key complex microprocessor is not space-qualified. We will discuss the procedures necessary to qualify a microprocessor for the natural space radiation environment. We also present the results from our single event upset tests on the 80186. The upset cross-section exhibited a threshold of 0.4 MeV-cm²/mg, a knee at 7 MeV-cm²/mg and an asymptotic value of 5x10-4cm². The upset cross-section did not depend on frequency in the 4-8 MHz range and increased by …

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Design Of A Small Satellite For Use In Astronautics Education, Walter Daniel Sep 1988

Design Of A Small Satellite For Use In Astronautics Education, Walter Daniel

Small Satellite Conference

The Naval Academy is pursuing a small satellite project to give midshipmen hardware and ground control experience. The concept is for a lightweight, gravity-gradient stabilized satellite to be deployed from a Get Away Special cannister; the payload would be two small, low-resolution imagers (one visible and one infrared). The 40 foot diameter ground station antenna being installed at the Naval Academy can receive a power of 10 milliwatts from a satellite that uses an omnidirectional antenna and is in a typical Space Shuttle orbit. Approximately 5 to 7 watts of power is constantly available to the payload of up to …

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Application Of Raman Spectroscopy To Small Satellites In Exploring Solar Bodies, James Cantrell, Greg Mccurdy Sep 1988

Application Of Raman Spectroscopy To Small Satellites In Exploring Solar Bodies, James Cantrell, Greg Mccurdy

Small Satellite Conference

Raman Spectroscopy is an active remote sensing method that can map planetary mineral and chemical abundances and their distributions. Raman spectroscopy can also be used to study the chemical composition of various planetary atmospheres. The remote raman technique utilizes a low power laser to stimulate raman scattering at the substance and a spectrometer receives the returned raman spectrum at the spacecraft. The returned spectrum contains the shifts in frequency, shifted from that of the incident laser light, that are characteristic of the substance. The intensity of the raman spectrum lines is proportional to the amount of the substance present. Thus, …

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Development Of A Responsive Small Spacecraft, P.A. Miller, C.A. Hughes Sep 1988

Development Of A Responsive Small Spacecraft, P.A. Miller, C.A. Hughes

Small Satellite Conference

The development of a small spacecraft bus is presented. The approach applied seeks to respond to the requirements of potential users as represented by a large data base of payload missions, while minimizing cost. The development results in a general purpose spacecraft design that is responsive to a wide range of mission requirements, and provides a clear definition of capabilities and interfaces to facilitate user mission design.

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A Modular Small Satellite Bus For Low Earth Orbit Missions, N.P. Bean Sep 1988

A Modular Small Satellite Bus For Low Earth Orbit Missions, N.P. Bean

Small Satellite Conference

The University of Surrey has demonstrated its capability in the field of small, low-cost spacecraft with the UoSAT-1 and 2 missions launched into low earth orbit in 1981 and 1984. Surrey Satellite Technology Ltd., a company formed by the University of Surrey, is now developing a flexible spacecraft bus based on the experience gained from these missions. The paper describes how the design philosophy used on the UoSAT spacecraft has been advanced to produce a bus providing basic power conditioning, telecommand, telemetry and attitude control functions. This basic bus is sufficient to support a variety of payloads, but the architecture …

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Designing A Small Satellite - Starsat, Thomas Lash Sep 1988

Designing A Small Satellite - Starsat, Thomas Lash

Small Satellite Conference

STARSAT, the Standardized Teaching and Research Satellite, is a small, low-cost satellite being designed and but It at the USAF Academy. The basic function of STARSAT is to expand upon NASA's Get-Away-Special concept by al lowing similar type payloads to be flown in low earth orbit for extended periods of time. As a standardized spacecraft bus, STARSAT will be able to support a variety of such research payloads. While research is a major goal, STARSAT is also an outstanding tool to aid in teaching undergraduate engineering students. This paper describes the technical specifications for the spacecraft, ground support, launch support …

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A Family Of Generic Earth Pointing Satellites, Jeanine Bowman, Francis Czopek Sep 1988

A Family Of Generic Earth Pointing Satellites, Jeanine Bowman, Francis Czopek

Small Satellite Conference

This paper outlines a family of generic earth pointing satellites. The smallest configuration is sized to fit a Get Away Special (GAS) container (2.5 cubic feet). The basic core of the largest member is sized to be scout launch vehicle compatible (18 cubic feet). The smallest member can easily accommodate 125 pounds of payload and generate 200 watts of electrical power. The largest can carry 500 pounds of payload and generate 1 Kilowatt of power. This family of earth pointing satellites is based on modular components that allow upward compatibility. To keep cost per unit volume low, tried and proven …

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The Italian Approach To Small Satellites For Low Cost Access To Space Developments, G. Rondinelli, G. Barresi, A. Cramarossa, F. Graziani Sep 1988

The Italian Approach To Small Satellites For Low Cost Access To Space Developments, G. Rondinelli, G. Barresi, A. Cramarossa, F. Graziani

Small Satellite Conference

Several technological institutions and scientific center are presently forbidden to access space exploration, because of the high costs involved with satellite development and launch. ITALSPAZIO has performed several studies directed toward the minimization of such costs. Possible design approaches are: use of a small bus capable to fly at marginal cost on expendable launch vehicles by paying delta-costs when passing from one launcher class to the upper next of the same launcher, (an example is constituted by the ARIANE IV when passing from AIRANE 40 to ARIANE 42s); use of left-over launcher capacities; use of subsystems and equipment’s developed for …

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The Avatar Small Spacecraft System, Joseph Leblanc Sep 1988

The Avatar Small Spacecraft System, Joseph Leblanc

Small Satellite Conference

American Microsat president Joseph A. LeBlanc will present the AVATAR Small Spacecraft System. The AVATAR Small Spacecraft System consists of the AVATAR satellite modules and the ground control and data collection facility. The AVATAR spacecraft is comprised of modules containing specific mission subsystems that are designed to work together or independently to satisfy mission requirements. Four modules provide payload space, control, propulsion and three axis stabilization. The different modules (described below) and the customer launch options will be discussed separately during the presentation. Common Services Module: The Common Services Module houses the spacecraft computer, the TT&C communications equipment, the attitude …

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Low Cost Station Keeping Maneuvers For A Small-Satellites Constellation In Tundra Orbits, A. Cramarossa, G. Rondinelli, F. Graziani Sep 1988

Low Cost Station Keeping Maneuvers For A Small-Satellites Constellation In Tundra Orbits, A. Cramarossa, G. Rondinelli, F. Graziani

Small Satellite Conference

A constellation of three small satellites placed, in highly inclined geosynchronous eccentric orbits equally spaced, can provide a continuous coverage of a service zone at high latitudes. Satellites on such orbits (TUNDRA) will spend most of the time around the apogee and each satellite of the constellation is required to be at a certain position in the orbit at a fixed time interval, in order to keep the constellation synchronism, which is requested by the user's antenna to have at switch-over time an isopower signal. To counteract the orbit perturbations (mainly due to lunisolar effects), that do not preserve the …

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Deep Space Missions For Small Satellites, Paula Butler, Alan Stein Sep 1988

Deep Space Missions For Small Satellites, Paula Butler, Alan Stein

Small Satellite Conference

Small satellites, with masses well under 100 kg, can perform useful deep space science missions for costs similar to those of low earth orbit and geosynchronous smallsats. Space Explorations has identified several interesting missions for smallsats, with the objective of developing "turnkey" space-science packages which would have a cost to the customer of $10,000,000 and be operable by one or a few people. We have analyzed one mission, a Lunar Polar Photographic Orbiter, in great detail over the last year. We conclude that it is commercially and scientifically feasible to produce a small lunar satellite which is capable of doing …

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An Approach To The Design Of A Lightweight Lunar Spacecraft, G.E. Sevaston, D.H. Lehman, K.T. Nock Sep 1988

An Approach To The Design Of A Lightweight Lunar Spacecraft, G.E. Sevaston, D.H. Lehman, K.T. Nock

Small Satellite Conference

The Quicksat study, undertaken at the Jet Propulsion Laboratory (JPL), had as its goal the development of low mass, low cost spacecraft that can be implemented within a relatively short time span. As part of this effort, JPL studied a lunar mission referred to as Lunar Prospector (LP). The LP spacecraft carries a spare Apollo gamma ray spectrometer (GRS) in a 100 km polar orbit about the moon in order to obtain a global map of surface composition. The primary mission objective is to search for water in the form of ice trapped within polar craters; this is viewed as …

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