Attitude Control Of Distributed Remote Sensing Satellite Formation Under Complex Constraints

As a platform of remote sensing technology,remote sensing satellite can telemeter the earth's surface in outer space.It is widely used in agriculture,forestry,water conservancy,meteorological monitoring,land survey,disaster warning and many other fields.In the new era,in order to meet the more stringent requirements of the application of satellite remote sensing technology,formation,agility and intelligence become the important directions of satellite remote sensing technology development.In this paper,the formation control of remote sensing satellite is taken as the technical background.Under the constraints of uncertainties and control system with limited input,the coordinated attitude control of spacecraft formation is studied.Aiming at the imaging mode of "cooperative observation of key areas with multisatellite" of remote sensing satellite formation,a computing model of attitude orientation of on orbit satellite gaze imaging is established.Combined with the requirements of the imaging mode for the fast attitude maneuver of large angle range and high attitude tracking accuracy of attitude control system,a two-stage attitude control method is designed.Firstly,the fast convergence of attitude control error is achieved by using Bang-Bang control,and then based on feedforward and feedback control and cascade control,high precision attitude tracking is realized.The simulation result shows that the attitude control strategy can basically meet the expected design requirements of fast attitude maneuver and high-precision attitude tracking.In this paper,the formation coordinated attitude control of remote sensing satellite is studied under the consideration of the constraints such as disturbance torque,uncertain of satellite moment of inertia and saturation of actuator.Firstly,based on Nussbaum gain theory,an adaptive attitude cooperative controller considering actuator saturation is designed.Then,by means of adaptive method and extended state observer,the uncertainties in the system can be estimated in real time,so that the controller can compensate the uncertainties in the mean while.The numerical simulation results verify the stability of the controller.In view of the fact that only some members of the spacecraft formation can obtain the attitude information of the pilot spacecraft,and the communication means in reality may bring the topology unidirectionality of the formation information network,based on the directed topology theory,this paper first establishes the modified Rodrigues parameter model of the formation attitude cooperative control,and then an attitude cooperative controller based on the neural network method is designed.In this method,neural network is used to approach the uncertainty of the system,and Nussbaum gain method is used to realize the saturation constraint of control torque,the control system has better control performance.Finally,the stability of the method is verified by numerical simulation.