Vigilância, previsão e controlo do ambiente espacial terrestre

The main objective of this project is to develop a new chain of new procedures (not yet available) to be adopted in every required stage to control the Earth's space environment. These stages are orbit determination (including satellite characterization), orbit propagation, and orbit transfer. For every stage, several procedures will be developed, most of them based on the modern mathematical framework described by the Theory of Functional Connections, combined with efficient optimization techniques. Each of these procedures has the potential to be added to the astrodynamics tools, contributing then to the control of the Earth's space environment. The new procedures developed in this project are associated with their respective tasks, among data collecting and processing (TASK 1), orbit determination and satellite characterization (TAKS 2), orbit prediction (TAKS 3), collision estimation (TAKS 4), and collision mitigation (TAKS 5). Every procedure developed in this project is derived in the respectives subtasks, and detailed in section 8 (Activities). The first TASK is based on techniques adopted to the purpose of observation and treatment of the available data. The techniques developed in TASK 2 are under the orbit determination scope. They must deal with raw data to determine the orbit and characterize the satellite. This characterization combined with optimization procedures are then adopted in the following procedures contained in TASK 3, to propagate the orbit according to the type and quantity of the available data, to the dynamical parameters of the characterized satellite, among others. The techniques developed in TASKS 2 and 3 will be integrated into a software (an algorithm) to be created in TASK 4 to estimate collision, considering the uncertainties involved. Finally, this software will use the procedure developed in the “orbit transfer” stage - to be investigated in TASK 5 - to select the best decision of maneuvering the satellite to avoid collision and mitigate debris. The type of maneuvers are studied in the last stage for both long term maneuvers (using continuous low thrust, like the one generated by a solar sail) and short term maneuvers (usually through the use of a propellant thruster). It is important to emphasize that the procedures developed in this project are not available neither in the literature nor in astrodynamics softwares / tools. This means that we propose an ambitious project to create a chain of tools capable to characterize the monitored satellite, determine and propagate its orbit, analyze risks of collisions in a network of satellites, and suggest maneuvers to mitigate these risks of collisions, both during and also after the lifetime of the satellite. In summary, this project consists in developing a chain of procedures related to space: processing observational data, orbit determination, orbit prediction, collision estimation, and collision mitigation. Most of the tasks are based on a state-of-the-art mathematical tool called Theory of Functional Connections. The chain of procedures will be integrated into an algorithm capable of performing a series of procedures which can be used to control the space environment.