| With the development of the scales of spacecraft projects,the demands for spacecraft attitude control are becoming more and more important today. Spacecrafts are working in the space environment,which is full of sorts of physical mediums. And these mediums will impact on the altitude movement of spacecraft. Spacecraft attitude control during propulsive maneuvers is complicated due to several factors as listed below:(i) nonlinear dynamics with time delays,(ii) modeling and parameter uncertainties,(iii) flexible modes due to fuel sloshing and appendages,(vi) constraints on propulsive force and torque inputs,(v) constraints on acceptable angular rates and attitude,(iv) autonomous reconfiguration requirements under failure conditions. The current control approaches are based on frequency domain methods such as PID control which assumes linear time invariant system dynamics. The advantages of these approaches are simplicity and ease of stability and robustness analysis. However,the decrease in performance and poor efficiency translates to additional payload and cannot meet the demand of current spacecraft control. Nonlinear Model Predictive Control (NMPC) is an effective method of solving multi-variable nonlinear system and has been used successfully in a number of industrial applications involving complex nonlinear processes such as petroleum chemical engineering and spaceflight domains with hard safety and actuator constraints. The remarkable stability and robustness properties of MPC observed in practice have been analyzed in a number of recent publications. The optimality of Nonlinear MPC design and its flexibility for reconfiguration make it an idea candidate for future spacecraft missions like attitude control using thrusters.This thesis presents the feasibility of Nonlinear Model Predictive Control implemented in spacecraft control and the optimality of increasing the control precision and decreasing the fuels expenditure. And the discussions are then focused on the simulation of spacecraft control using Function-space Model Predictive Control algorithm as mentioned below:1. Problem formulation,modeling and simulation of the spacecraft attitude and trajectory control.2. Designation of Nonlinear Model Predictive Controllers.3. Controller Tuning and Testing including Stability and Robustness Analysis.4. Test results to the implementation of MPC for spacecraft control.5. The problems to be studied in future are presented.This thesis studies the spacecraft control using Nonlinear Model Predictive Control and computer simulations are applied in it. The main results fall into two main areas.1. Application of the standard MPC algorithms was not possible due to the nature of the spacecraft dynamic model. Several methods were proposed to alleviate these difficulties,with varying success. MPC was successfully applied to the spacecraft rate control (setpoint and tracking problems) when applied on an internally stabilized model of the plant dynamics.2. A new predictive control algorithm,the Function-space Model Predictive Control(F-MPC) method,was developed based on a function-space optimization of the control input for attitude control. This method yielded very promising results on precision pointing tasks,and is also applicable to the slewing task. Pointing errors of less than 0.05 degrees were achievable with off-line nominal control computation . One key advantage of the MPC feedback stabilization algorithm is that it can handle some well known difficult cases that can arise in attitude control. For example,if one of the actuator fails,conventional feedback algorithms can no longer position a spacecraft to arbitrary orientation while this algorithm remains viable.Preliminary investigations of the MPC approach to attitude control lead to the following conclusions:I . Because of increasingly stringent requirements on the cost and control performance for future missions,it is imperative to try to improve on the abilities of traditional control methods by using some aspects of model...
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