With the increasing emphasis on space applications and satellite systems, the U.S. military, industry, and academic communities have identified a need for improved high-fidelity satellite simulation. This paper describes the systematic development of the laboratory-based satellite simulator sponsored by the Air Force Institute of Technology (AFIT), WrightPatterson Air Force Base, Ohio. The simulation satellite (SIMSAT) supports a variety of research areas, including attitude control, precision pointing, satellite dynamics, vibration suppression, and integrated cormoIler design. System development began with the purchase of a three-axis gas bearing from Space Electronics, Inc., which mimics a torquefree space environment using a very low-friction air cushion. Project challenges included integration of attitude control software/hardware, controller design and testing, incorporation of high-output power storage devices, remote communications, highfrequency data collection, structural design, and userinterface development. space systems, the USAF has shifted its focus ii-om being strictly an “air” force to becoming the premiere “space and air force” by the year 2020. Accordingly, AFIT has responded by developing curriculum and conducting research to support space operations and cutting-edge space technologies. Unfortunately, much of the space-related work at AFIT has been limited to computer simulation or stationary experiments due to a lack of representative space hardware. Consequently, AFIT sought to augment its laboratory facilities with a more realistic spaceplatform simulator. Development of a satellite simulator allows implementation of practical experiments, demonstration of fundamental techniques, and extension of AFIT research . capabilities in support of Air Force, Department of Defense, and industry needs. Additionally, a satellite simulator provides a hands-on tool for enhancing the learning experience of AFIT graduate students, particularly in the area of satellite attitude dynamics.