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Full-Text Articles in Aerospace Engineering
Periodic Methods For Controlling A Satellite In Formation, Erin Y. Carraher
Periodic Methods For Controlling A Satellite In Formation, Erin Y. Carraher
Theses and Dissertations
Precise position determination and control is necessary to accomplish proposed satellite formation flying missions of ground movement target indication and synthetic aperture radar. This thesis combines the estimation and control techniques of past AFIT theses with various time-varying and time-invariant LQG control methods. Linear time-invariant control is ideal for on-board satellite estimation and control applications, freeing-up the satellite's limited computational capacity. Using a dynamics frame transformation from the nodal frame to an orbital frame, a higher fidelity, time-periodic model produced nearly identical results for either time-varying or time-invariant control for many scenarios. Scenarios included initial perturbations in the radial, in-track, …
Microdot - A Four-Bit Microcontroller Designed For Distributed Low-End Computing In Satellites, Anthony R. Woodcock
Microdot - A Four-Bit Microcontroller Designed For Distributed Low-End Computing In Satellites, Anthony R. Woodcock
Theses and Dissertations
Many satellites are an integrated collection of sensors and actuators that require dedicated real-time control. For single processor systems, additional sensors require an increase in computing power and speed to provide the multi-tasking capability needed to service each sensor. Faster processors cost more and consume more power, which taxes a satellite's power resources and may lead to shorter satellite lifetimes. An alternative design approach is a distributed network of small and low power microcontrollers designed for space that handle the computing requirements of each individual sensor and actuator. The design of microdot, a four-bit microcontroller for distributed low-end computing, is …