title: Adaptive back-stepping tracking control for rotor shaft tilting of active magnetically suspended momentum wheel.
abstract: Two-dimensional gyroscopic torque can be produced by tilting the rotor shaft of the active magnetically suspended momentum wheel. The nonlinear magnetic torque is analyzed and then an adaptive back-stepping tracking method is proposed to deal with the nonlinearity and uncertainty. The nonlinearity of magnetic torque is represented as bounded unknown uncertainty stiffness, and an adaptive law is proposed to estimate the stiffness. Combined with back-stepping method, the proposed method can deal with the uncertainty. This method is designed by Lyapunov stability theory to ensure the stability, and its effectiveness is validated by simulations and experiments. These results indicate that this method can realize higher tracking precision and faster tracking velocity than the conventional cross feedback method to provide high precision and wide bandwidth outputting torque.
authors.affiliation: School of Instrument Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China; Guangdong Key Laboratory of Popular High Performance Computers, Shenzhen University, Shenzhen 518060, China. Electronic address: buaayyj@126.com.
authors.forename: Yuan-jin
authors.initials: YJ
authors.lastname: Yu
authors.affiliation: School of Instrument Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China.
authors.forename: Jian-cheng
authors.initials: JC
authors.lastname: Fang
authors.affiliation: School of Instrument Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Xiang
authors.affiliation: School of Instrument Science and Opto-electronics Engineering, Beihang University, Beijing 100191, China.
authors.forename: Chun-e
authors.initials: CE
authors.lastname: Wang
keywords: Adaptive; Back-stepping; Lorentz force-type magnetic bearing; Magnetically suspended momentum wheel; Rotor shaft tilting; Tracking control