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Research On Attitude Tracking Control Of Combined Spacecraft

Posted on:2024-04-01Degree:MasterType:Thesis
Country:ChinaCandidate:S S WangFull Text:PDF
GTID:2542306926966409Subject:Electronic information
Abstract/Summary:PDF Full Text Request
On-orbit service is a kind of space service technology for the purpose of spacecraft maintenance,parts disassembly and garbage removal in orbit,which can improve spacecraft performance,extend spacecraft life and avoid losses caused by commo n spacecraft failures,and has vital practical and academic values.Attitude control after target acquisition is one of the important components of on-orbit service and a prerequisite for on-orbit service.When performing on-orbit service,the service spacecraft captures the target spacecraft and generates a combined spacecraft,but the combined spacecraft has different parameter characteristics because the target spacecraft has different types of application areas and operation states.Therefore,it is necessary to model the combinatorial spacecraft formed in different cases and design different controllers for different motion models and control problems.The main research of this paper is as follows:Firstly,the attitude tracking error models of different combinatorial spacecraft are established.When the target is a cooperative spacecraft,the attitude error model of the combined body as a whole is chosen to model the combined body as a whole,considering that its rotational inertia and other parameters are completely known;however,when the target is a non-cooperative spacecraft,the rotational inertia and other parameters are unknown,and the combined body as a whole is modeled differently fro m the cooperative target,and the service spacecraft is chosen to model the combined body as a whole to model the attitude error of the captured non-cooperative spacecraft.The attitude error model of the service spacecraft after the capture of the non-cooperative target is chosen.Then,the attitude tracking control of the combined spacecraft at the cooperative target is studied.Firstly,the combination is considered to be affected by external perturbations,and a strongly robust terminal sliding mode is used to suppress the external perturbations,while the control strategy of designing a fast non-singular terminal sliding mode is chosen in order to improve the convergence speed of the control system.Then,further considering the uncertainty of the rotational inertia of the combiner also exists,the adaptive fast non-singular terminal sliding mode based control strategy is designed using real-time estimation of the rotational inertia of the combiner.Finally,the effectiveness of the proposed control strategy in the attitude tracking control of the spacecraft with cooperative target combinators is verified by si mulation experiments.Finally,the attitude tracking control of the combinatorial spacecraft for non-cooperative targets is studied.Considering the jitter that exists in the terminal sliding mode in practical engineering applications is generally difficul t to eliminate,and the advantage of referring to the higher-order fully driven system theory is that the design controller can obtain a linear constant system with arbitrary characteristic structure and the design process is simple and convenient.Based on this,the direct parameterization method using the higher-order fully driven system theory is chosen.First,a nonlinear disturbance observer is designed to estimate the complex disturbances of the system and compensate them by a compensation controller;then the service spacecraft error model is upscaled to a second-order fully driven system;immediately afterwards,a parametric controller is designed by using the direct parameterization method and combining the observations of the observer.Finally,the effectiveness of the proposed control strategy in the attitude tracking control of the non-cooperative target combiner spacecraft is verified by simulation experiments.
Keywords/Search Tags:combined spacecraft, attitude tracking, sliding mode control, direct parametric approach, disturbance observer
PDF Full Text Request
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