Robust attitude acquisition for micro-satellite

Purpose - The purpose of this paper is to investigate the problem of the initial attitude detumbling and acquisition for micro-satellite using geomagnetism with the aid of the pitch momentum bias, and the application of the feedback linearization method, H_∞ and m-synthesize control theory in the robust attitude acquisition controller design. Design/methodology/approach - The pitch flywheels establish the momentum bias state in the beginning of the detumbling stage and keep the momentum bias state thereafter. The geomagnetic change rate feedback detumbling controller is used to detumble the micro-satellite and the gyroscope rigidity is utilized to capture orbital negative normal orientation in the detumbling and attitude acquisition phase. Feedback linearization method is adopted to obtain the linear attitude dynamics. Based on the feedback linearization model, a quasi proportion differential (PD) controller is designed, meanwhile H_∞ and μ-synthesis control theories are adopted to synthesis the robust attitude acquisition controllers. Findings - The pitch momentum bias-aided attitude detumbling and acquisition method make the capture of the orbital negative normal orientation faster and more accurate than the classical initial operation process. Quasi PD and H_∞ have greater robustness than the classical PD attitude acquisition controller in normal geomagnetic case; quasi PD and m-synthesis have greater robustness than the classical PD attitude acquisition controller in magnetic storm case. Originality/value - Provides pitch momentum bias-aided attitude detumbling and acquisition method for the micro-satellite and the robust attitude acquisition controller design technology.