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Investigation Into Low-Cost Propulsion Systems For Small Satellite Missions, Jerry Sellers, Malcolm Paul, Maarten Meerman, Robert Wood

Small Satellite Conference

Low-cost satellites need low-cost propulsion systems. The research summarised in this paper has focused on investigating low-cost propulsion system options for small satellites with specific application to the upcoming UoSAT-12 mini satellite mission. The research began by looking at available propulsion system technology. Low-cost spacecraft engineering techniques were then explored to identify specific system cost drivers for further investigation. This led to parallel research efforts aimed at (1) basic research & development into hybrid rockets to characterise their applicability to low-cost spacecraft, and (2) applied research into low-cost spacecraft systems engineering - to design and implement a system for UoSAT-12. …

Spacecraft Computer System, A High Performance Flight Data System For Nasa's Small Explorer Satellites, Quang Hong Nguyen

Small Satellite Conference

The high performance, light weight, small volume and low power flight data systems required by small class satellites push the limits of today's technology. Requirements for high-speed telemetry downlink, fully autonomous operation, and a large data storage have caused NASA' s Small Explorer (SMEX) Project to create a new generation data system. NASA Goddard Space Flight Center (GSFC) Code 743 designed, built and tested such a data system, called Spacecraft Computer System (SCS), for SMEX missions. The flight qualified SCS has been successfully delivered to the SMEX Submillimeter Wave Astronomy Satellite (SWAS) spacecraft. In addition, the SCS has been selected …

Energy Storage Options For Low-Cost Spacecraft Applications, D.F. Pennington, S.E. Wecker, R.D. Wright, D.K. Coates

Small Satellite Conference

Several energy storage options currently exist for small satellite power systems. These include nickel-hydrogen, nickel-cadmium and nickel-metal hydride batteries. Nickel-hydrogen is available only as a spaceflight qualified system and is therefore relatively high in cost. Nickel-metal hydride batteries are available only in a small capacity, commercial cylindrical version which limits usefulness in aerospace applications. Both aerospace and commercial nickel-cadmium batteries are available, providing another degree of freedom in matching battery selection to the specific cost and power requirements of the spacecraft. Other near-term options which may become available include aerospace grade nickel-metal hydride, silver-metal hydride and lithium ion batteries. Other …

Fast Auroral Snapshot Mission Unique Electronics Complete Spacecraft Electronics Contained In A Single Enclosure, Lamar Dougherty, Timothy Gruner, Jonathan Wilmot, Michael Chiville

Small Satellite Conference

The Fast Auroral Snapshot (FAST) Mission Unique Electronics (MUE), housed in a single container, controls all major spacecraft functions. The functions include, Command and Data Handling (C&DH), Attitude Control and Stabilization (ACS), battery charge control and power distribution which comprise the Power System Electronics (PSE), thermal sensing and control, pyrotechnic device firing, spacecraft health and safety functions, Instrument Data Processing Unit (IDPU) interface and Small Launch Vehicle (SLV) interface. Each of the MUE functions have been optimized to conserve mass and power, utilize packaging, mechanical hardware and electronics components that are suitable for the radiation environment in the Auroral regions. …

The Submillimeter Wave Astronomy Satellite Attitude Control Software Design, Mark Anderson, Miriam Wennersten, Joseph Bonnett, Adrian Hill

Small Satellite Conference

The Submilimeter Wave Astronomy Satellite (SWAS) was selected for flight by NASA in 1989 as a part of the Small Explorer (SMEX) program. SWAS's primary science objective is to conduct high spectral resolution surveys of galactic molecular clouds. The SWAS Attitude Control System (ACS) is three-axis controlled, zero momentum stabilized, and is capable of performing subarcminute pointing. This paper will discuss the design of the software components which comprise the Attitude Control System Software. The paper first describes the high level requirements which governed the architecture of the Attitude Control System Software. Next, the context in which the software resides …

The Attitude Control System Design For The Submillimeter Wave Astronomy Satellite, Charles Clagett, Thomas Correll, Michael Fennell, Frederick Niles, Victoriano Untalan Iii, Roger Chen, Walter Daniel

Small Satellite Conference

The Submillimeter Wave Astronomy Satellite (SWAS), the third Small Explorer spacecraft, has a sophisticated three-axis stellar pointing attitude, control subsystem. This mission requires slewing the satellite up to 3 degrees and settling on target within 15 seconds to a 57 arc-second accuracy once per minute. Hardware and software configuration will be briefly described. The spacecraft has many modes and submodes of increasing complexity and accuracy. These modes use a variety of routines including: Kalman Filtering, Magnetic Calibration, AutoTargeting, Slewing and Fine Control, Momentum Management, and Stellar Acquisition. Simulations have shown that the Attitude Control System (ACS) not only meets sub-arc-minute …

Control Systems For The Mars Pathfinder Mission, Dankai Liu, Steve Franklin

Small Satellite Conference

The Mars Pathfinder Project began in October 1993, along with the Near Earth Asteroid Rendezvous Program, as one of the first Discovery Program missions funded by NASA. The Mars Pathfinder Project is planned, designed, launched and operated by JPL Mars Pathfinder Project Team under the management of JPL Mars Exploration Project Office. The project is intended to be JPL's most visible demonstration of a successful better, faster, cheaper mission in accordance with NASA's new direction.

Mars Pathfinder will place a lander vehicle and rover on the Mars Surface and conduct significant technology and science experiments. The principle mission objective is …

Design Progress In The Satellite Quick Research Testbed (Squirt) Program, Christopher Kitts, Robert Twiggs

Small Satellite Conference

Stanford University's Satellite Systems Development Laboratory (SSDL) is achieving positive results in its yearly educational program known as the Satellite Quick Research Testbed (SQUIRT). This project's goal is to produce student engineered microspacecraft capable of servicing state-of-the-art research payloads. SQUIRT spacecraft are about 25 pounds, 18 inches in diameter, nine inches tall, and have a cash budget for parts of approximately $50,000. After 18 months of work, the first SQUIRT design team is in the final assembly and test stage of the Stanford Audio Phonic Photographic Infrared Experiment (SAPPHIRE) satellite. This microspacecraft will be used to space characterize experimental infrared …

First Class Science On A Coach Class Ticket, Robert Meurer

Small Satellite Conference

"Faster - better - cheaper" is more than a catchy phrase at Orbital Sciences Corporation. On April 3, 1995, the first of OSC's MicroLab no Orbital Experiment Service missions was launched on a flawless Pegasus launch. The first PicoLab is expected to be placed on contract later this year for launch in 1997. Both of these two carrier concepts offer scientists, experimenters and students the opportunity to fly dedicated missions at a fraction of the cost of primary payloads. This paper introduces the MicroStar Common Core Vehicle (CCV) series of small satellites. The MicroStar CCV series is based on a …

Spartan Lite: Genesis Of A Small Satellite, Evan Goldstein, Stewart Meyers

Small Satellite Conference

Goddard Space Flight Center's (GSFC) Space Science Directorate (SSD) came to the Special Payloads Division (SPD) to discuss the idea of extending the mission life of sounding rocket class instruments with a small satellite. The SSD provided a preliminary study that recommended using a five cubic foot Hitchhiker (HH) or Get Away Special (GAS) canister to eject an ASTRO HITCHHIKER satellite into a Space Transportation System (STS) orbit. The SPD interdisciplinary engineering team reviewed this preliminary study and identified restrictions on the proposed satellite's design. The SPD then asked the SSD to provide requirements for various types of instruments. Combining …

The Mars Pathfinder Commercial Hardware And Microgyro (Chμg) Experiment: Lessons Already Learned, Douglas Caldwell

Small Satellite Conference

The Commercial Hardware and Microgyro (CHμG) experiment was designed to demonstrate the feasibility of using commercial off-the-shelf modules (PC Cards) and microelectromechanical sensors (MEMS) on space missions and to obtain performance data on both in a deep-space environment so as to gain a better understanding of these two technologies which promise to substantially reduce the cost, mass and power of future spacecraft. Simultaneously, the experiment was designed to provide information and resources to Mars Pathfinder (MPF) which could enhance that mission's value. For various technical and programmatic reasons, the experiment was radically descoped and the "commercial hardware" aspect of the …

Applying Fiber Support Technology To Small Satellite Systems, Scott Jensen, Clair Batty, Dave Mclain

Small Satellite Conference

Cryogenically cooled components in infrared instruments designed by Utah State University's Space Dynamics Laboratory traditionally have been mounted on glass-epoxy composite (G-10) cylinders for thermal isolation. Ensuring adequate mechanical stiffness to withstand typical launch loads often compromises the desired thermal isolation and conduction parasitic heat loads become a concern. Beginning with a senior design project in the Mechanical and Aerospace Engineering Department, a new approach to rigidly supporting cold components using high performance fibers in tension was initiated. The development effort included consideration of several candidate fibers for tensile strength, shear strength, creep, and thermal conductivity as well as a …

Miniaturized Rf Remote Sensing Instruments, James Brady, Greg Mceachron

Small Satellite Conference

Until recently, miniaturization of RF remote sensing instruments has not been cost effective. Aperture size has governed launch vehicle selection and spacecraft mass has been well within margins. However, as technologies improve for miniature spacecraft, multiple spacecraft can fit within small launch vehicle shrouds. Down-sizing payloads is now advantageous. E-Systems is applying state-of the- art technologies to significantly reduce the size and weight of RF remote sensing payload electronics. Current activities include the development of MMIC modules; the application of advanced, materials; the development of multiband feeds; and the development of micromachined filters and other RF components. These technologies will …

Science Instrumentation For The Student Nitric Oxide Explorer, Scott Bailey, Richard Kohnert, Robert Mcfeeters, Aimee Merkel, Erica Rodgers, Stanley Solomon, Stanley Straight, James Vian, Thomas Woods

Small Satellite Conference

The Student Nitric Oxide Explorer (SNOE) is a small satellite to be designed, built and operated at the University of Colorado under the Student Explorer Demonstration Initiative (STEDI) from the Universities Space Research Association. The goal of the STEDI program is to demonstrate that low cost satellite missions can be done with large student involvement. The primary science goals of SNOE are to measure thermospheric nitric oxide (NO) and its variability over the lifetime of the mission. SNOE will also monitor the solar irradiance at soft X-ray wavelengths and the auroral energy deposition at high latitudes. Three science instruments are …

Tethers For Small Satellite Applications, Joseph Carroll, John Oldson

Small Satellite Conference

This paper begins with a sketch of the history of space tether concepts and then describes the four tether orbital flight tests flown in 1992-94 (TSS-1, SEDS-1, PMG, and SEDS-2). It reviews currently funded flight experiments and studies aimed at near-term flights. Next it provides a brief tutorial on some key aspects of space tether concepts. Finally it homes in on issues and applications relevant to small satellites, and gives specific examples of typical mission scenarios, tradeoffs, benefits, and costs.

Benefits Of Low-Power Stationary Plasma Thruster Propulsion For Small Satellites, Craig Clauss, Dennis Tilley, David Barnhart

Small Satellite Conference

The paper examines some of the benefits to be gained in using Stationary Plasma Thruster (SPT) propulsion onboard small spacecraft. SPTs were developed in Russia, and have an extensive flight history, with over 70 thrusters flown since 1971. A joint venture company is qualifying a complete propulsion subsystem incorporating Russian thrusters with western electronics and propellant feed components. The availability of thrusters which operate with input powers under 500 watts, as well as the simple, compact design of the SPT makes it well suited for application on small satellites. An interplanetary mission proposed to NASA's Middle Explorer (MIDEX) program, uses …

Pegasus® Shared Launch Accommodations For Microsat And Secondary Payloads, Cary Pao, Jaime Fernandez, Robert Fulton

Small Satellite Conference

Launch services in the emerging "smaller, faster, cheaper" aerospace industry have evolved into a highly cost driven environment to meet more demanding requirements for systems performance. The introduction of the Student Explorer Demonstration Initiative (STEDI) and the designation of Pegasus as the NASA Ultralite Expendable Launch Vehicle are examples of the demand for more cost-effective access to space. This trend requires a change in the way Iaunch vehicles are used from the traditional single payload mission on a dedicated booster to launching multiple payloads on a single flight. Operations in this manner will attract a larger customer base at a …

Smaller, Better, Faster - Nasa's Ultralite Expendable Launch Vehicle Services (Uelvs), W. Cutlip

Small Satellite Conference

The signing of the Ultralite Expendable Launch Vehicle Services (UELVS) contract on December 23, 1994, marked the end of a fast-track, six-month procurement process and the beginning of a new "smaller-better-faster" operational paradigm within NASA's Mixed Fleet Program. Managed by the Goddard Space Flight Center's (GSFC) Orbital Launch Services Project (OLS), UELVS reflects a departure from the established Medium and Small Expendable Launch Vehicle Services (MELVS and SELVS) in both management philosophy and level of NASA technical oversight. The intent of this paper is to discuss the foundation and implementation of this paradigm and future plans for UELVS.

Building "Smaller, Cheaper, Faster" Satellites Within The Constraints Of An Academic Environment, Richard Lu, Tanya Olsen, Michael Swartwout

Small Satellite Conference

Student driven satellite projects are working under the constraints of extremely limited budgets, short development times due to student turnover, limited technical expertise, and other academic time commitment pressures. These are issues prevalent throughout the university system, but many programs do not directly address these realities. So how can educational programs promote a "smaller, cheaper, faster" philosophy and at the same time effectively realize its potential? This question was asked of the students in Stanford University's Satellite Systems Development Laboratory (SSDL). In response, the Satellite QUIck Research Testbed (SQUIRT) program was developed to give students the opportunity to participate in …

Earth Reference Imager Experiment For Satellite Attitude Determination, Jose Delatorre, Jr.

Small Satellite Conference

The Earth Reference Imager (ERI) experiment on board the ASUSat 1 student satellite will provide valuable attitude information to validate the new attitude sensors along with the GPS data. Using the concept of triangulation, the satellite's tilt, swing, height, azimuth, and coordinates will be attained from an image of the Earth. This information will then be compared with the attitude sensors to confirm the data received from the satellite.

Soft X-Ray Detection System For The Catsat Small Satellite, Glenn Forrest, Steve Lynch

Small Satellite Conference

We present an innovative approach to detecting low energy x-ray emissions from cosmic gamma ray bursts. Our design employs an array of avalanche photodiodes (APDs) to measure x-rays from 500 eV to 10 keV over a wide field of view, approximately 2π steradians. These silicon devices are ideal in many ways for small satellite use. This effort is driven by the scientific requirements of the CATSAT mission. Our objective is to meet the mission requirements within the time scale and cost constraints of the STEDI program. CATSAT is a joint effort between the University of New Hampshire, Weber State University …

The Opal Satellite Project: Continuing The Next Generation Of Small Satellite Development, Brian Engberg, Jeff Ota, Jason Suchman

Small Satellite Conference

The Satellite Systems Development Laboratory (SSDL) in the Department of Aeronautics and Astronautics at Stanford University was created in an effort to promote a new philosophy about building satellites. The main tenets of this philosophy include the design and construction of reliable spacecraft that are smaller, developed within a one year time frame, and employ cheaper "off-the-shelf" parts. As a result of these criteria, one must take an alternative approach to the engineering project, including rapid prototyping of hardware, careful evaluation of mission requirements, and an overall approach which emphasizes development of the whole system rather than individual subsystems. The …

The Design Of The Sapphire Separation System And Launch Vehicle Interface, Alison Nordt

Small Satellite Conference

Small satellites create unique challenges in the design of deployment mechanisms and attachments to launch vehicles. The SAPPHIRE satellite, designed and built by students at Stanford University, is 35 pounds and is designed to be launched as a secondary payload on any of a variety of launch vehicles. The design of the interface and separation system is intended to optimize simplicity, size, weight, and cost. The SAPPHIRE design uses a single hold down bolt with a single separation spring. Deployment is achieved through the use of a Frangibolt (TiNi Alloy Co.). This device utilizes properties of the shape memory alloy …

Spartnik: Student Developed Micro Satellite, Benefits Education And Industry, Thomas Romano, Jason Leong

Small Satellite Conference

This paper describes a micro-satellite design and construction project. SPARTNIK, the capstone design project of the Aerospace Engineering undergraduate program was conceived with the industry ideal of "faster, cheaper, and better." With minimal funds and resources, SPARTNIK's main goal is to educate students for the real world, through the design and manufacturing of a working micro-satellite. A multidisciplinary team of Aerospace, Mechanical, and Electrical Engineering undergraduate students was formed to confront this challenge. This project will help prepare engineering students to contribute to the emerging field of micro-satellite development. Classified as a secondary payload, SPARTNIK will conform to the size …

Ionospheric Plasma Technology: Asusat 1 & Advanced Spacecraft Propulsion Systems, Charles Hewett

Small Satellite Conference

The Ionospheric Plasma Research Experiment (IPRE) is the scientific payload on board Arizona State University's student designed, ASUSat 1, which is scheduled for launch in late 1995 on a Orbital Sciences Corporation Pegasus rocket. The IPRE consists of a group of integrated instruments and sensors designed for innovative space and Earth science applications that integrate solar power and ionospheric plasma for lowthrust propulsion, attitude control, and electrical power generation. Propulsion devices that use the natural occurring plasma of a planet's ionosphere eliminate the need for on-board propellant supplies and provide the capability of maintaining low-altitude orbits indefinitely. In this manner, …

A System Architecture To Advance Small Satellite Mission Operations Autonomy, Sam Siewert, Linden Mcclure

Small Satellite Conference

A system architecture concept that supports automation of small satellite mission operations functions is presented along with a working prototype. The concept and prototype provide an automation framework which enables much more advanced levels of operational autonomy than is typical of current systems. This scalable architecture provides a risk mitigating stepwise approach toward achieving high levels of operational autonomy to enable significant operations cost savings through mission performance management by exception. The prototype consists of an October 1997 manifested Space Shuttle Hitchhiker payload along with the software and hardware described in this paper.

Mission Overview Of Engineering Test Satellite, Kitsat-3, Sungheon Kim, Sungdong Park, Dan Keun Sung, Soon Dal Choi

Small Satellite Conference

SaTReC has developed and operated two micro-satellites, KITSAT-1 and 2 successfully. Since middle of 1994, the third satellite, KITSAT-3, has been being developed. Its main mission is to perform onorbit engineering tests of core technologies for high performance small satellite. This includes 3- axis stabilization, high speed data transmission and solar panel deployment. In addition to engineering tests, there are 3 payloads; Earth Observation System (EOS) using a linear CCD camera with 17m resolution and 3 spectral bands, Space Environment Scientific Experiment (SENSE) and KITSAT Data Collection System (KDCS). KITSAT-3 is planned to be launched in middle of 1997. This …

Innovative Spacecraft Architecture Study, H.W. Swenson, S.P. Presley, D.G. Heflinger, R.N. Constant, S.D. Szogas, P. Avrin, R.T. Carlson, C.R. Husbands

Small Satellite Conference

The baseline concept used as the basis for the Innovative Spacecraft Study (ISA) was developed and published by Eric Sundberg and John Meekins in a white paper entitled, "Uniform Interface, Sectional Spacecraft" and a presentation, "Wireless Spacecraft". The paper proposed that it was necessary to develop a new paradigm for the design, fabrication, integration, test, launch, and operations of spacecraft because of the new geopolitical situation, long development cycles, and reduced military funding. The key assertion to the proposed new approach is the use of standard interfaces among "modularized" spacecraft sections with a high speed optical data bus for data …

The Design And Management Of A Low Cost Scientific Stedi Mission, D.J. Forrest, K. Levenson, K. Reister, J. Parsons, A. Owens, C. Whitford

Small Satellite Conference

The release of the Student Explorer Demonstration Initiative (STEDI) Opportunity of Announcement in May 1994 generated a tremendous amount of excitement and activity within the small satellite community. To meet the very tight constraints of the STEDI program (2 years, $4 million) a new paradigm for small science satellites must be created which centers on university involvement. This paper describes the collaborative process for the three university CATSAT project and focuses on some of the issues that are important for a successful university small satellite program. These points include: running a program from within a university environment, creating a model …

The Student Nitric Oxide Explorer, S.C. Solomon, S.M. Bailey, T.E. Holden, D.C. O'Connor, J.P. Perich, M.A. Salada, G.A. Stafford, K.R. Taylor, J.E. Vian, P.R. Withnell

Small Satellite Conference

The Student Nitric Oxide Explorer (SNOE) is a small scientific spacecraft designed for launch on a Pegasus™ XL launch vehicle for the USRA Student Explorer Demonstration Initiative. Its scientific goals are to measure nitric oxide density in the lower thermosphere and analyze the energy inputs to that region from the sun and magnetosphere that create it and cause its abundance to vary dramatically. These inputs are energetic solar photons in the EUV and X -ray spectral regions, and energetic electrons that are accelerated into the polar regions, where they cause auroral disturbances and displays. Both of these phenomena are aspects …