Mathematical simulation method can be adopted to check flight characteristic of UAV, also can be adopted to simulate hardware experiments of unmanned aerial vehicle (UAV), then related flight experiments can be perfor...Mathematical simulation method can be adopted to check flight characteristic of UAV, also can be adopted to simulate hardware experiments of unmanned aerial vehicle (UAV), then related flight experiments can be performed. The simulation method can reduce the flight periods, cost and risk. UAV flight model research play an important role in simulation and modeling in initialize periods of the UAV producing. The study of the paper focuses on the aerodynamic force modeling work of UAV based on Simulink. The designed model not only can afford mathematics simulation experiment but also will do benefits to the research of flight control, navigation guidance of UAV.展开更多
Current research on quadrotor modeling mainly focuses on theoretical analysis methods and experimental methods,which have problems such as weak adaptability to the environment,high test costs,and long durations.Additi...Current research on quadrotor modeling mainly focuses on theoretical analysis methods and experimental methods,which have problems such as weak adaptability to the environment,high test costs,and long durations.Additionally,the PID controller,which is currently widely used in quadrotors,requires improvement in anti-interference.Therefore,the aforementioned research has considerable practical significance for the modeling and controller design of quadrotors with strong coupling and nonlinear characteristics.In the present research,an aerodynamic-parameter estimation method and an adaptive attitude control method based on the linear active disturbance rejection controller(LADRC)are designed separately.First,the motion model,dynamics model,and control allocation model of the quad-rotor are established according to the aerodynamic theory and Newton-Euler equations.Next,a more accurate attitude model of the quad-rotor is obtained by using a tool called CIFER to identify the aerodynamic parameters with large uncertainties in the frequency domain.Then,an adaptive attitude decoupling controller based on the LADRC is designed to solve the problem of the poor anti-interference ability of the quad-rotor and adjust the key control parameter b0 automatically according to the change in the moment of inertia in real time.Finally,the proposed approach is verified on a semi-physical simulation platform,and it increases the tracking speed and accuracy of the controller,as well as the anti-disturbance performance and robustness of the control system.This paper proposes an effective aerodynamic-parameter identification method using CIFER and an adaptive attitude decoupling controller with a sufficient anti-interference ability.展开更多
Flexible wings with a high aspect ratio own prominent nonlinear effects on the aeroelastic behaviors due to the geometrically large deformation and the nonlinear unsteady aerodynamic force referring to a strongly dyna...Flexible wings with a high aspect ratio own prominent nonlinear effects on the aeroelastic behaviors due to the geometrically large deformation and the nonlinear unsteady aerodynamic force referring to a strongly dynamic stall.This study proposes an efficient method to calculate the nonlinear flutter of the flexible wing in a fast way.First,the geometrically nonlinear deformation of the flexible wing under aerodynamic load is calculated based on a newbeam model only having two generalized rotational freedom,which reduces the computing time drastically for engineering practice.Then the deformed flexible wing is regarded as a curved beam to considering the geometrical nonlinearity via the shape of applied curved beam.The curvature of the curved beam is fitted based on its static deformation.Thereby,the flutter of the flexible wing with large deformation can be simply solved by the linear vibration theory of the curved beam.Further,the ONERA dynamic stall model is used to describe the nonlinear unsteady aerodynamic force.In the end,the flutter behavior of the flexible wing is gained using the transfer function method for small computational cost.Illustrative examples demonstrate the validity of the present method through existing analytic solutions and published results.展开更多
文摘Mathematical simulation method can be adopted to check flight characteristic of UAV, also can be adopted to simulate hardware experiments of unmanned aerial vehicle (UAV), then related flight experiments can be performed. The simulation method can reduce the flight periods, cost and risk. UAV flight model research play an important role in simulation and modeling in initialize periods of the UAV producing. The study of the paper focuses on the aerodynamic force modeling work of UAV based on Simulink. The designed model not only can afford mathematics simulation experiment but also will do benefits to the research of flight control, navigation guidance of UAV.
基金Supported by National Natural Science Foundation of China(Grant No.61501493).
文摘Current research on quadrotor modeling mainly focuses on theoretical analysis methods and experimental methods,which have problems such as weak adaptability to the environment,high test costs,and long durations.Additionally,the PID controller,which is currently widely used in quadrotors,requires improvement in anti-interference.Therefore,the aforementioned research has considerable practical significance for the modeling and controller design of quadrotors with strong coupling and nonlinear characteristics.In the present research,an aerodynamic-parameter estimation method and an adaptive attitude control method based on the linear active disturbance rejection controller(LADRC)are designed separately.First,the motion model,dynamics model,and control allocation model of the quad-rotor are established according to the aerodynamic theory and Newton-Euler equations.Next,a more accurate attitude model of the quad-rotor is obtained by using a tool called CIFER to identify the aerodynamic parameters with large uncertainties in the frequency domain.Then,an adaptive attitude decoupling controller based on the LADRC is designed to solve the problem of the poor anti-interference ability of the quad-rotor and adjust the key control parameter b0 automatically according to the change in the moment of inertia in real time.Finally,the proposed approach is verified on a semi-physical simulation platform,and it increases the tracking speed and accuracy of the controller,as well as the anti-disturbance performance and robustness of the control system.This paper proposes an effective aerodynamic-parameter identification method using CIFER and an adaptive attitude decoupling controller with a sufficient anti-interference ability.
基金The support of the Natural Science Foundation of China(Grant no.11702325)the Natural Science Foundation of Hebei Province of China(Grant no.A2018210065)is highly appreciated.
文摘Flexible wings with a high aspect ratio own prominent nonlinear effects on the aeroelastic behaviors due to the geometrically large deformation and the nonlinear unsteady aerodynamic force referring to a strongly dynamic stall.This study proposes an efficient method to calculate the nonlinear flutter of the flexible wing in a fast way.First,the geometrically nonlinear deformation of the flexible wing under aerodynamic load is calculated based on a newbeam model only having two generalized rotational freedom,which reduces the computing time drastically for engineering practice.Then the deformed flexible wing is regarded as a curved beam to considering the geometrical nonlinearity via the shape of applied curved beam.The curvature of the curved beam is fitted based on its static deformation.Thereby,the flutter of the flexible wing with large deformation can be simply solved by the linear vibration theory of the curved beam.Further,the ONERA dynamic stall model is used to describe the nonlinear unsteady aerodynamic force.In the end,the flutter behavior of the flexible wing is gained using the transfer function method for small computational cost.Illustrative examples demonstrate the validity of the present method through existing analytic solutions and published results.
