In this paper,a hybrid passive/active vibration(HPAV)controller of a loosely connected spacecraft consisting of a servicing satellite,a target and an X-shape structure isolator is first proposed to suppress vibrations...In this paper,a hybrid passive/active vibration(HPAV)controller of a loosely connected spacecraft consisting of a servicing satellite,a target and an X-shape structure isolator is first proposed to suppress vibrations of the system when subjected to the impulsive external excitations during the on-orbit missions.The passive dynamic response of the combined system can be adjusted appropriately to achieve the desired vibration isolation performance by tuning the structural parameters of the bio-inspired X-shape structure.Moreover,the adaptive control design through dynamic scaling technique is selected as the active component to maintain high vibration isolation performance in the presence of parameter uncertainties such as mass of the satellite platform,the damping and rotation friction coefficients of the X-shape structure.Compared with the pure passive system and the traditional spring-mass-damper(SMD)isolator,the HPAV strategy witnesses lower transmissibility,smaller vibration amplitude and higher convergence rate when subjected to the post-capture impact.Numerical simulations demonstrate the feasibility and validity of the proposed hybrid control scheme in suppressing vibrations of the free-floating spacecraft.展开更多
The control strategy is presented using passive and active hybrid magnetically suspended flywheels(P&A MSFWs),which can help meet the requirements of high precision and high stability for earth-observation satellit...The control strategy is presented using passive and active hybrid magnetically suspended flywheels(P&A MSFWs),which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P&A MSFW has more rotation degrees of freedom(DOFs)since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law(SMC)to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law.展开更多
文摘In this paper,a hybrid passive/active vibration(HPAV)controller of a loosely connected spacecraft consisting of a servicing satellite,a target and an X-shape structure isolator is first proposed to suppress vibrations of the system when subjected to the impulsive external excitations during the on-orbit missions.The passive dynamic response of the combined system can be adjusted appropriately to achieve the desired vibration isolation performance by tuning the structural parameters of the bio-inspired X-shape structure.Moreover,the adaptive control design through dynamic scaling technique is selected as the active component to maintain high vibration isolation performance in the presence of parameter uncertainties such as mass of the satellite platform,the damping and rotation friction coefficients of the X-shape structure.Compared with the pure passive system and the traditional spring-mass-damper(SMD)isolator,the HPAV strategy witnesses lower transmissibility,smaller vibration amplitude and higher convergence rate when subjected to the post-capture impact.Numerical simulations demonstrate the feasibility and validity of the proposed hybrid control scheme in suppressing vibrations of the free-floating spacecraft.
文摘The control strategy is presented using passive and active hybrid magnetically suspended flywheels(P&A MSFWs),which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P&A MSFW has more rotation degrees of freedom(DOFs)since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law(SMC)to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law.