Adaptive Angular Velocity Tracking Control of Spacecraft with Dynamic Uncertainties

The tracking of orientation and angular velocity is a primary attitude control task for an on-orbit spacecraft.The problem for a rigid spacecraft tracking a desired angular velocity profile is addressed using an adaptive feedback control.An angular velocity feedback tracking algorithm is firstly developed based on the precisely known attitude dynamics of the spacecraft,and the global tracking of the control algorithm is proved based on the Lyapunov analysis.An adaptation mechanism is then designed to deal with the dynamic uncertainties of the spacecraft.Such an adaptation mechanism enables the controller to track any desired angular velocity trajectories even in the presence of uncertain inertia parameters,although it does not guarantee the inertia tensor being precisely identified.To verify the effectiveness of the proposed adaptive control policy,computer simulations on dynamic equations of a spacecraft are conducted and their results are discussed.

Comment on the paper “Hydromagnetic thin film flow of Casson fluid in non-Darcy porous medium with Joule dissipation and Navier's partial slip”

The present comment concerns some doubtful results included in the abovepaper.

变惯量多体曲轴轴系发动机动力学仿真

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基于Pro/E的渐开线内花键安装盘参数化设计

对渐开线内花键安装盘在Pro/E环境下的参数化设计过程的分析,得出安装盘重量、转动惯量等所需参数从而大幅提高了设计效率和数据计算精度,并举例说明该模型通用性良好,可满足不同规格的渐开线内花键安装盘的计算需求。