is paper presents the control system design process of a novel tilt-rotor unmanned aerial vehicle (TRUAV). First, a new configuration scheme with the tilting rotors is designed. en, the detailed nonlinear mathematical model is established, and the parameters are acquired from designed experiments and numerical analyses. For control design purposes, the dynamics equation is linearized around the hovering equilibrium point, and a control allocation method based on trim calculation is developed. To deal with the actuator saturation and uncertain disturbance problems for the novel TRUAV, an improved flight control law based on the combination of the robust servo linear quadratic regulator (RSLQR) optimal control and the extended state observer (ESO) is proposed. e designed flight control law has a simple structure with a high reliability in engineering. Simulations and hovering flight tests are carried out to verify the effectiveness of the mathematical model and the proposed control strategy.

This paper addresses the aerodynamic modeling, observer-based state-feedback robust control and sensor fault detection for a laboratory ducted coaxial-rotor UAV (DCUAV). First, by introducing the main model elements of this novel unmanned vehicle, the detailed nonlinear mathematical model of the hovering flight UAV is presented. Second, through introducing a weighting matrix and a new form of changeof-variables, a new method is proposed by designing two different systems simultaneously as detector and controller. An observer-based controller is proposed to achieve the control objective and finite-frequency sensor fault detection objective simultaneously. The observer-based controller design method is derived from a new formulation of linear matrix inequality (LMI), which can achieve the prescribed H ∞ performance, H − performance and the stability of the closed-loop system. By constructing a new matrix decomposition form, the simultaneous design of detector parameters and controller parameters is solved. Finally, simulations are conducted for the hover flight with disturbances and sensor faults, the results show the satisfactory control performance and fault detection performance.

The working principle of the motor can cause unbalanced magnetic pull (UMP) between stator and rotor unavoidably. Previous research about nonlinear vibration excited by UMP was focused on the rotor supported by traditional mechanical bearings or gas bearings. However, the magnetic levitation rotor is particular due to the low rigidity provided by the active magnetic bearing (AMB). UMP amplifies rotor vibration in the resonant zone and further excites the nonlinear electromagnetic force, thus producing different vibration phenomena. The paper calculates rotor orbit, spectra analysis, and time-history plot with numerical methods and studies the influence of the rotation speed, eccentricity, key control parameters, and UMP on rotor dynamics in detail. Results illustrate displacement response spectra of the magnetic levitation rotor are quite different from previous research results. The appearing frequency components are inducted by universal formulas in this paper. Furthermore, research shows a slight adjustment of the control parameters affect significantly harmonic components and vibration characteristics. The research results have practical reference significance for fault diagnosis, feature recognition, and controller optimization of the AMB-rotor system.