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The Solar Anomalous And Magnetospheric Particle Explorer (Sampex) Power System Design And Performance, Anisa Ahmad, Harry Culver, James Jagielski, John Lyons, Gopalakrishna Rao, Ernest Rodriguez
The Solar Anomalous And Magnetospheric Particle Explorer (Sampex) Power System Design And Performance, Anisa Ahmad, Harry Culver, James Jagielski, John Lyons, Gopalakrishna Rao, Ernest Rodriguez
Small Satellite Conference
The Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX) spacecraft is the first mission of the NASA Goddard Space Flight Center Small Explorer program. The spacecraft was successfully launched July 3, 1992. The SAMPEX power system is a Direct Energy Transfer design with Gallium Arsenide Solar Arrays, and a Super Nickel Cadmium Battery. The power system is a single string system with functional redundancy, designed to minimize weight, volume and power consumption. This paper will give an overview of the power system and present beginning of life flight performance data.
The Isosat Small Satellite: A Design In Isogrid Technology , Joseph Greathouse, Mark Hines, Kevin Jezak, Gilbert Moore, Reed Nielsen, Rex Ridenoure, William Watt
The Isosat Small Satellite: A Design In Isogrid Technology , Joseph Greathouse, Mark Hines, Kevin Jezak, Gilbert Moore, Reed Nielsen, Rex Ridenoure, William Watt
Small Satellite Conference
ISOSAT, a small hexagonal shaped satellite structure, was designed and constructed in the Industrial Technology Department at Utah State University as a senior research project using automated manufacturing techniques and incorporating the "Isogrid" structure concept. Isogrid applications can be found in projects such as Skylab, most cylindrical structural elements of the Delta rocket and in the engine shrouds of Boeing's new 777 commercial airliners. The basis of the Isogrid is the repeating pattern of equilateral triangles which make up the structure. This pattern, machined into solid aluminum plates, results in a substantial weight savings with an acceptable reduction in structural …
Producing A Low Cost, Space Qualified Computer By Ruggedizing Commercial Computer Cards , Gregory Dirks
Producing A Low Cost, Space Qualified Computer By Ruggedizing Commercial Computer Cards , Gregory Dirks
Small Satellite Conference
A low cost space qualified computer using thermally and dynamically enhanced commercial circuit cards has been developed at Southwest Research Institute (SwRI) on an internal research program. This computer, the SC-6, has been fabricated, tested and delivered to clients for use on the upcoming Commercial Experiment Transporter (COMET) mission. Thermal enhancements provide conduction paths from the electronic components to the 'housing; from which the heat may be removed by conduction and/or radiation. Thermal vacuum tests confirm operation with a baseplate temperature of between -20 and +60°C. Dynamic enhancement is achieved by attaching a stiffener/damper frame directly to the circuit card …
Radiation-Induced Power Degradation For Gaas/Ge Solar Arrays, Thomas Woike
Radiation-Induced Power Degradation For Gaas/Ge Solar Arrays, Thomas Woike
Small Satellite Conference
This paper presents new radiation-induced power degradation data for GaAs/Ge solar arrays applicable to missions ranging from low earth orbit (LEO) to geosynchronous earth orbit (GEO) and compares these results to silicon arrays. These results are based on recently published radiation damage coefficients for GaAs/Ge cells. The power density ratio (GaAs/Ge to Si BSF/R) has been found to be as high as 1.83 for the proton-dominated worstcase altitude of 7408 km (MEO). Based on the EOL GaAs/Ge solar array power density results for MEO, missions which were previously considered infeasible may be reviewed based on these more favorable results. The …
Hete Telemetry Ranging Subsystem, Greg Huffman
Hete Telemetry Ranging Subsystem, Greg Huffman
Small Satellite Conference
The HETE (High Energy Transient Experiment) satellite, a joint project between MIT Center for Space Research and AeroAstro, is a high energy gamma ray burst/X-ray/UV observatory platform. In order to provide accurate time stamping of gamma ray burst events, a clock accurate to within 100 Ils of Universal Time (UT) is required on the satellite. This paper presents a clock setting/ranging subsystem that is incorporated into the HETE telemetry system at no additional weight or power consumption. This method makes use of augmenting the data scrambler with a PN ranging code with unique words which allows accurate ranging and clock …
Saflr: A Small-Satellite Program For Two-Way Environmental Data Collection And Distribution , A. Ginari, G. Lehmann
Saflr: A Small-Satellite Program For Two-Way Environmental Data Collection And Distribution , A. Ginari, G. Lehmann
Small Satellite Conference
A new approach in space technology arises in various areas utilizing small satellites, also called μSATs. Implementing modem equipment especially in the field of electronics and computers, leads to powerful systems which are able to cover wide areas of application. In addition, new launch capabilities, such as secondary payloads and piggy-backs on CIS launchers enables a "low cost" approach for satellite based applications. In this context OHB-System develops the small satellite system called SAFJR. (Satellite For Information Relay) with unique communication capabilities. The major operation is aimed to two-way data collection and distribution of environmental “in-situ" measurements. Moreover, the implemented …
Temisat: A Microsatellite System For Autonomous Enviromental Monitoring Service, Brunella Pavesi, Giuseppe Rondinelli, Nikolaos Balteas
Temisat: A Microsatellite System For Autonomous Enviromental Monitoring Service, Brunella Pavesi, Giuseppe Rondinelli, Nikolaos Balteas
Small Satellite Conference
TELESPAZIO is developing the first professional system program using TEMISAT micro-satellite. The service offer will be dedicated to Enviromental Monitoring for data collection and distribution from autonomous Networks. The system is composed by two microsatellite units with low cost satellite based TDMA/SCPC scheme, a Mission Control Center and two different types of terminal; Collection Center terminal and User terminal. A brief description of the satellite subsystem is outlined.
International Activities In Small Satellites; Comparisons With U.S. Programs, Brian Horais
International Activities In Small Satellites; Comparisons With U.S. Programs, Brian Horais
Small Satellite Conference
Despite relatively low levels of Government funding when compared with U.S. small satellite activities, the international small satellite community has achieved a number of impressive successes. These range from the impressive imagery transmitted from the University of Surrey's UoSAT-5 to the demonstrated small satellite launch system versatility and affordability of the Ariane Auxiliary Structure for Space Payloads (ASAP). Capabilities exist in a growing number of countries outside of the United States to design, fabricate, and in some cases launch small satellites into low earth orbit. Activities in India and Israel are being joined by emerging space programs in such countries …
Recent Status Of Small Satellite Study In Japan, Takashi Iida, Ryutaro Suzuki, Atsushi Nakajima
Recent Status Of Small Satellite Study In Japan, Takashi Iida, Ryutaro Suzuki, Atsushi Nakajima
Small Satellite Conference
This paper describes the recent status of small satellite study in Japan focusing on the activities of the Small Payload WorkShop (SPWS) which was established in January, 1990. The objectives of SPWS are to review the development of small satellite and its launching system, to study the possible mission, to exchange information, to pick up and study the issues to be solved and to contribute to the good and efficient development of the future plan of small satellite utilization in Japan. The discussion to initiate the SPWS is reviewed briefly. The paper describes the recent studies of small satellites missions …
Micro-Satellites - Areas Of Utilization And Design Principles, G.V. Molgshev, G.A. Fopov
Micro-Satellites - Areas Of Utilization And Design Principles, G.V. Molgshev, G.A. Fopov
Small Satellite Conference
Among 6-7 problems of modern astronautical designing there is one which is not evident but very actual. The paper shows the place of Small Satellite Systems (SSS) among modern missions. They are especially useful in experimental and modeling researches which are based on new technical lessons. They will have special role is serving of manned orbital stations and large satellites.
Launch Vehicle Options For Small Satellite Systems , Robert Cullen
Launch Vehicle Options For Small Satellite Systems , Robert Cullen
Small Satellite Conference
The small satellite industry faces a special challenge when it comes to the selection of a launch vehicle. Given the limited number of dedicated lifters and a disadvantageous payload weight/cost ratio, the launch planner must often compromise satellite system performance to remain within the profiles of throw weight, altitude, inclination, and cost associated with the obvious choices of launch vehicles. This paper provides a detailed look at the world's inventory of launch vehicles, particularly those that are appropriate for use as dedicated lifters of small satellites and those that can accommodate small satellites as non-primary payloads. The term small satellite …
Increasing Space Access Availability For Small Payloads: The Pacastro Launch Vehicle , Rick Fleeter, Frank Mcloughlin, Ray Millst
Increasing Space Access Availability For Small Payloads: The Pacastro Launch Vehicle , Rick Fleeter, Frank Mcloughlin, Ray Millst
Small Satellite Conference
This paper familiarizes the Small Satellite community with the capabilities and advantages offered by the PacAstro launch vehicle and its applications to low-cost launch needs. At a projected cost of $5M per launch, the 2-stage, pressure-fed liquid fueled vehicle is designed to transport 225 kg (500 Ibm) to a 750 km (405 nm) altitude circular polar orbit, or to a 1200 km (650 nm) altitude circular equatorial orbit. The smooth burning engine provides a gentle vibration environment and can be throttled, shut-down, and restarted to accommodate accurate orbit insertion. The large 1.5 m 10 and 2.4 m long payload volume …
Missions Of Small Satellites Launched By The J-I Launch Vehicle , Atsuo Tsuiki, Toshio Doura, Yoshiaki Suzuki
Missions Of Small Satellites Launched By The J-I Launch Vehicle , Atsuo Tsuiki, Toshio Doura, Yoshiaki Suzuki
Small Satellite Conference
This paper presents the concept of the small satellites launched by the 1-1 launch vehicle of the National Space Development Agency of JAPAN (NASDA). On this concept, the missions of the small satellites are for the experiment and the validation of the earth observation. The satellite communications, and the others on orbit. For efficient achievements of these missions, the common satellite bus will be adopted for the solid launch vehicle J-I, in order to develop the each small satellite system quickly by low-cost.
Achieving Performance Taliorability In The Castor 120 Solid Rocket Motor, David Buhaly
Achieving Performance Taliorability In The Castor 120 Solid Rocket Motor, David Buhaly
Small Satellite Conference
The methods used by Thiokol Corporation to achieve unprecedented performance tailorability in the Castor 120™ solid rocket motor will be discussed.. This motor is a 120,000-pound class motor designed for use on expendable launch vehicle systems. It employs a carbon-epoxy composite case, Class 1.3 HTPB propellant, and a vectorable nozzle. A key objective was to build a motor that could be used in fast stage, strap-on, and second stage applications. Each application has differing thrust, action time, nozzle vector duty cycle. and structural capability requirements. In contrast, most existing large solid rocket motors are designed for a single application. With …
The Development Of The Northern Satellite Service, Rolf Skatteboe
The Development Of The Northern Satellite Service, Rolf Skatteboe
Small Satellite Conference
Launch- and operational cost have been prohibiting factors for small satellite systems. and it is becoming clearer that a new philosophy must be adopted to accommodate the reduced budgets of such systems. This paper discusses the design of an integrated launch facility for small polar orbiting satellites and sounding rockets. It focuses on the development of a cost-effective total service for integration, launch, operation and TT&C for micro-satellites, called the Northern Satellite Service (NSS). The goal is to create a flexible service, and offer this service to the international market The proposed launch facility is based on the existing infrastructure …
Launch Vehicle Technology And The Impact Upon Lightsat Design, Jason O'Neil
Launch Vehicle Technology And The Impact Upon Lightsat Design, Jason O'Neil
Small Satellite Conference
Low cost satellites require low cost access to space. Today, several companies are attempting to provide competitive launch services for small satellites. DSI, which has launched 18 lightweight satellites, has extensive experience in the areas of satellite design, launch planning, integration and test. The selection of an ELV has important impacts upon the design of the satellite. This paper focuses on 2 areas: 1.) the environments of the small ELVs and 2.) The corresponding impacts upon the satellite design. The author uses recent flight experiences to create a template which the designer can use to better understand the engineering constraints …
Single Event Upset And Latchup Sensitive Devices In Satellite Systems , Richard Maurer, James Kinnison
Single Event Upset And Latchup Sensitive Devices In Satellite Systems , Richard Maurer, James Kinnison
Small Satellite Conference
We present a decision tree to systematically evaluate the potential use of single event sensitive devices in spacecraft systems. We present several concrete examples of branches on the tree.
Resistance To Satellite Failures Of Leo Communication Systems , Thomas Wolf, Jean-Jacques De Ridder
Resistance To Satellite Failures Of Leo Communication Systems , Thomas Wolf, Jean-Jacques De Ridder
Small Satellite Conference
This paper presents a satellite failure analysis for Low Earth Orbit (LEO) constellations with continuous global coverage. Worst case failure configurations are identified for polar orbit constellations and the coverage performance deterioration 'is evaluated by computer simulations. Then, the probability of having a number of satellite failures in a given constellation is evaluated as a function of satellite reliability. It is shown that the probability of occurrence of a worst case failure configuration is very low, and that the most probable configuration is a uniform distribution of the defective satellites. As a consequence, the maximum tolerable number of satellite failures …
In-Place Assembly And Testing Of Satellites, Franklin Williams Jr.
In-Place Assembly And Testing Of Satellites, Franklin Williams Jr.
Small Satellite Conference
This paper describes an innovative approach to testing satellites that reduces test flow time and risk. The approach uses a uniquely designed assembly stand, created by INTRASPACE, that accommodates the satellite assembly process as well as in-place environmental testing. The satellite is assembled, functionally tested and environmentally tested on a single assembly stand platform. The platform rotates in 2-axes to facilitate access to all areas of the spacecraft. For environmental test, a "bell jar" vacuum dome is placed over the spacecraft. Vacuum, Thermal Vacuum and Acoustic Testing are made possible by the modular arrangement of the dome, liquid nitrogen cold …
Low-Cost Quick-Look Radiation Testing Of Electronic Components For The Mars Observer Camera , S.M. Brylow, T.A. Soulanille
Low-Cost Quick-Look Radiation Testing Of Electronic Components For The Mars Observer Camera , S.M. Brylow, T.A. Soulanille
Small Satellite Conference
The development of modern electronics has far outstripped the inventory of components for which radiation tolerance has been determined and published. New component characteristics require a more integrated approach to radiation tolerance in system design. The Mars Observer Camera performance requirements could not be met with a design restricted to components of established radiation hardness. A balanced approach that intimately involved radiation effects in the system design process was required. This included low-cost, quick turnaround testing of total ionizing dose and heavy ion induced single event phenomena of upset and latchup. The results were used to inform the system design, …
High-Data-Rate Communication Techniques For Small Satellites, Robert Bokulic
High-Data-Rate Communication Techniques For Small Satellites, Robert Bokulic
Small Satellite Conference
Modulation and coding techniques that are both power and bandwidth-efficient are examined at the system level in this paper. Such techniques include convolutional encoding with QPSK modulation and the relatively new trellis-coded modulation. Power and bandwidth trade-offs are discussed, a sample link calculation is given, and hardware implementation is considered.
A Unique New Antenna Technology For Small (And Large) Satellites, Bernard Raab, Larry Sikora
A Unique New Antenna Technology For Small (And Large) Satellites, Bernard Raab, Larry Sikora
Small Satellite Conference
The application of large antennas in spacecraft is often limited by available volume, as well as by the more usual mass limitation. Shroud dimensions usually determine the maximum aperture which can be carried without resorting to complex and potentially unreliable unfurling mechanisms. This applies all the more in a small-satellite environment with the smaller available launch volumes and severe mass limits of this species. FLAPS (Flat Parabolic Surface) is a newly developed technology for RF reflector surfaces which frees the spacecraft designer from the packaging rigidity of the common parabolic dish. It offers the ability to essentially duplicate the capability …
Downlink Signal Level And Error Measurements For Pacsat-1, Robert Diersing
Downlink Signal Level And Error Measurements For Pacsat-1, Robert Diersing
Small Satellite Conference
The PACSAT-l store-and-forward amateur radio satellite was placed into low earth orbit (LEO) on January 22, 1990 using the Ariane Structure for Auxiliary Payloads (ASAP). Most of the first year of operation was spent on application software development with full time operation of file server and file broadcast services beginning in late 1990. During 1991, both ground station and satellite-based software matured and stabilized such that the satellite sees a high volume of daily use both by individual amateur radio station operators and stations acting as gateways for terrestrial packet radio networks operating in the Amateur Radio Service. The purpose …
Using Digital Signal Processors On Small Satellites, Don Lefevre, Daniel Mulally, Mark Heiberger
Using Digital Signal Processors On Small Satellites, Don Lefevre, Daniel Mulally, Mark Heiberger
Small Satellite Conference
Digital Signal Processing integrated circuits (DSPs) have improved terrestrial communications systems by allowing the implementation of greatly improved transmitters and receivers. In applications from dial-up modems, to echo-free conference phones, to customer-specific hearing aids, DSPs have allowed the implementation of functions that would be impractical without them. However, DSPs have had limited use in small satellites due to lower available data rates and relatively high power consumption. Also, most of the existing DSPs have not been space qualified. Improvements in semiconductor processes are allowing the construction of integrated circuits (ICs) with much smaller features. In fact, 0.6 micron processes are …
A Laser Downlink For Small Satellites Using An Optically Modulating Retroreflector, Gary Jensen, Charles Swenson
A Laser Downlink For Small Satellites Using An Optically Modulating Retroreflector, Gary Jensen, Charles Swenson
Small Satellite Conference
This paper presents an earthsatellite-earth laser downlink system which is compact, simple, and low-power enough to be considered for use on very small satellites. Presented here is the design, feasibility study, and results from preliminary "proof of concept" testing of the critical components.
A Compact Radar Altimeter Satellite For Monitoring Global Climate Change, J.A Giannini, C.C. Kilgus, E.L. Reynolds
A Compact Radar Altimeter Satellite For Monitoring Global Climate Change, J.A Giannini, C.C. Kilgus, E.L. Reynolds
Small Satellite Conference
Altimetry has become the focus of global climate studies because it is the only tool available able to provide both mesoscale (100-500 kIn) and basin-scale (10,000 kIn) circulation information on a global, synoptic basis. . The Atlas-launched Navy Geosat mission proved the capability of the radar altimeter to measure the mesoscale ocean features. A lightsat compatible Geosat Follow-On Technology Model (GTM) altimeter, capable of Scout or Pegasus launch and with half the weight and power (63-lbs and 69-W) of the Geosat altimeter, was developed and built at JHU/APL. This altimeter demonstrated the feasibility of a compact satellite version of Geosat. …
The Development Of A Low Cost Earth Sensor, Richard Anderson
The Development Of A Low Cost Earth Sensor, Richard Anderson
Small Satellite Conference
A Low Cost Earth Sensor (LCES) is under development at Lockheed Missiles & Space Company (LMSC) that will be adaptable to both Geosynchronous (GEO) and Low Earth Orbit (LEO) applications. The LCES is based on the latest pyroelectric detector array technology. It has been designed with a minimum of components, using ASIC and hybrid electronics techniques. The sensor will be contained in a single package with a weight of less than 2.5 pounds and a power requirement of less than 2.0 watts. It can be designed to be fully redundant. There are both low accuracy (± 0.5 deg) and high …
A Low-Cost Small Satellite Space Radar System, Bernard Raab, Robert Bartlett
A Low-Cost Small Satellite Space Radar System, Bernard Raab, Robert Bartlett
Small Satellite Conference
The advantages of space-based radar have been frequently noted for such applications as environmental monitoring, crop detection, soil-moisture determination, coastal ice measurement, and all-weather surveillance, to name just a few. The FLAPSTM ("Flat Parabolic Surface") antenna technology developed by Malibu Research, enables the conception of a smallsatellite radar system. The design described in this paper is that of a lightweight surveillance satellite capable of being launched on a Pegasus booster. It is capable of detecting small ships and aircraft, such as may be required for drug-interdiction missions and other all-weather surveillance applications. The FLAPSTM antenna has many of the features …
Precision Quartz Oscillators And Their Use In Small Satellites, J.R. Norton, J.M. Cloeren
Precision Quartz Oscillators And Their Use In Small Satellites, J.R. Norton, J.M. Cloeren
Small Satellite Conference
Space-qualified precision quartz oscillators are ideal instruments for use aboard small satellites as the heart of the spacecraft navigation system as well as for other applications such as radio science experiments, pseudorandom communications, and altimetry. This paper provides information on the history of precision quartz oscillator use aboard small satellites and discusses potential applications and design tradeoffs. The Johns Hopkins University Applied Physics Laboratory pioneered the use of precision quartz oscillators in small satellites in 1958. Current performance parameters of oscillators designed by the Applied Physics Laboratory will be presented along with mass and power considerations.
Electronic Packaging Techniques In The Mars Observer Camera, Timothy Cushing, Roger Applewhite
Electronic Packaging Techniques In The Mars Observer Camera, Timothy Cushing, Roger Applewhite
Small Satellite Conference
Volume constraints of small spacecraft place difficult packaging requirements on electronic designs. High component counts per unit area and stiff, lightweight boards with large surface to volume ratios will define the state of the art for PWB assemblies. The Mars Observer Camera, a high resolution imager on the Mars Observer mission, required innovative developments in these design areas to satisfy the difficult volume constraints placed on the instrument. These included qualifying a high-reliability "I-lead" surface mount technique used throughout the electronic system. This enabled a density with 4500 parts (including large DIPs and flatpacks), boards, and cabling in 900 cubic …