Dual RF Astrodynamic GPS Orbital Navigator Satellite (DRAGONSat) - 07.08.15
Dual RF Astrodynamic GPS Orbital Navigator Satellite (DRAGONSat) will demonstrate autonomous rendezvous and docking (ARD) in low Earth orbit (LEO) and gather flight data with a global positioning system (GPS) receiver strictly designed for space applications. ARD is the capability of two independent spacecraft to rendezvous in orbit and dock without crew intervention. DRAGONSat consists of two picosatellites (one built by the University of Texas and one built by Texas A and M University) and the Space Shuttle Payload Launcher (SSPL); this project will ultimately demonstrate ARD in LEO. Science Results for Everyone
Information Pending Experiment Details
David B. Kanipe, Johnson Space Center, Houston, TX, United States
Robert Bishop, Ph.D., University of Texas, Austin, TX, United States
Robert Steve Provence, Ph.D., Johnson Space Center, Houston, TX, United States
Tim Straube, Johnson Space Center, Houston, TX, United States
Helen Reed, Ph.D., Texas A&M University, College Station, TX, United States
Glenn Lightsey, Ph.D., University of Texas, Austin, TX, United States
University of Texas, Austin, TX, United States
Texas A&M University, College Station, TX, United States
United States Department of Defense Space Test Program, Johnson Space Center, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Department of Defense (DoD) - Retired
ISS Expedition Duration
March 2009 - October 2009
Previous ISS Missions
DRAGONSat will be perfomed on the 2JA mission to the ISS.
- Dual RF Astrodynamic GPS Orbital Navigator Satellite (DRAGONSat) is a low cost, low risk project designed to prove that autonomous rendezvous and docking (ARD) can be performed successfully in space.
- It will also provide invaluable flight data for the global positioning system (GPS) receiver designed strictly for space applications to demonstrate precision relative navigation and precision real-time navigation as well as provide orbit determination.
To successfully travel beyond low Earth orbit (LEO), to the moon, Mars and beyond the ability for two spacecraft to autonomously rendezvous and dock (ARD) in space must be demonstrated. Dual RF Astrodynamic GPS Orbital Navigator Satellite (DRAGONSat) is a collaboration project with two universities (University of Texas at Austin and Texas A and M University) to each build a satellite that will ultimately rendezvous and dock with each other in space without the benefit of human intervention.
DRAGONSat is an anticipated eight-year program with a launch of the satellites approximately every two years. The first three missions will test individual components and subsystems while the final mission will culminate with the successful docking of two satellites. Each mission builds upon the previous mission culminating in a fully autonomous rendezvous and docking mission. In addition, the universities are required to use a global positioning system (GPS) receiver designed by National Aeronautics and Space Administration (NASA) in order to gather flight data in the space environment to determine its functionality. The objective is to demonstrate precision real-time navigation capability as well as precision relative navigation between the two satellites.
This project will demonstrate ARD in space and provide NASA with actual flight data that is directly linked to the Exploration Systems Architecture Study Technology Focus Area under Avionics and Software. ARD will be utilized in the Constellation Program for unmanned cargo vehicles and in space assembly. Data from DRAGONSat will have a direct impact on the development of that capability.
Student education is enhanced by engaging in a real world scenario including requirements, geographical distance, system engineering, project management, and dealing with diverse cultures. This project will also develop critical skills that will be invaluable to NASA in the future as the aerospace workforce continues to mature and retire. This project also gives NASA insight into the best and brightest students.
DRAGONSat is comprised of two 5 inches x 5 inches x 5 inches satellites which are launched from the orbiter payload bay. A picosatellite is defined as being 5 inches x 5 inches x 10 inches, so each of these satellites is actually one half of a picosatellite. Both satellites are composed of aluminum with a mass of approximately 7.5 kg. The surface of each picosatellite is covered with photo voltaic cells which will enable a longer active life in orbit. Each satellite also has a dipole antenna and two antennas for the GPS receiver. The satellites are ejected from the SSPL which is located on the payload bay sidewall.
The two satellites comprising DRAGONSat are launched together in the Space Shuttle Payload Launcher (SSPL) which is attached to the side wall of the orbiter payload bay. They are adjacent in the SSPL but when ejected, and once they are at a safe distance from the Space Shuttle, they will separate and begin the experiment. The data subsequently collected will be downlinked to ground stations for as long as the satellites are able to transmit.
Texas A&M University’s AggieSat2 and University of Texas’ Bevo-1 launched together from shuttle flight STS-127/2JA on July 30, 2009. The 2 satellites failed to completely separate, which hindered communications through antennas that were partially captive within Bevo-1. Despite this failure, AggieSat2 operated for 230 days in low-Earth orbit until re-entry on March 17, 2010. While mission success requirements to download 2 full orbits of GPS data were not achieved, the NASA-provided DRAGON GPS unit was commanded to operate for one 90-minute period and data samples throughout this period were downlinked that show the GPS unit was operational and tracking GPS satellites. Texas A&M students also developed a model to predict a satellite’s drag coefficient. Undergraduate students managed, implemented, and documented the entire spectrum of the satellite life cycle, and many students obtained real-time spacecraft operations experience as well (Graves 2012).^ back to top
Graves JT, Perez JA, Reed H, McLelland A, Kanipe DB, Provence RS, Runkle TA. AggieSat2 student satellite mission. 50th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition, Nashville, Tennessee; 2012 January 9-12 17 pp.
Ground Based Results Publications
Computer-generated depiction of the University of Texas Satellite: PARADIGM Structural Layout. Image provided courtesy of NASA.
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Computer-generated depiction of the Texas A&M University Satellite: AggieSat2 Structural Layout. Image provided courtesy of NASA.
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