Dynamic Modeling And Control Of Amphibious Moving Mass Coaxial UAV With Payload

This paper investigates an amphibious unmanned aerial vehicle(UAVs)with the capabilities for water surface floating and aerial flight.To fulfill specific mission requirements,a novel amphibious moving mass control coaxial UAV is proposed,which employs the displacement of an internal mass slider to regulate the UAV’s attitude and position.This UAV demonstrates the capability of suspending loads and performing takeoff/landing on water surfaces.A mathematical model for the moving mass control coaxial UAV is established,and the dynamic characteristics of the UAV in water and air environments are analyzed.Leveraging the moving mass control coaxial UAV,position and attitude control algorithms are designed based on an active disturbance rejection control methodology.Lastly,control algorithm design is carried out for the UAV under load suspension conditions.The main research contributions are summarized as follows:In order to address the challenges posed by the complexity and susceptibility to wear and tear of traditional coaxial unmanned aerial vehicles(UAVs)that rely on intricate and fragile variable-pitch mechanisms,a novel moving mass control coaxial UAV is proposed.The Newton-Euler modeling method is employed to establish the Newtonian motion model of the moving mass control coaxial UAV and derive expressions for the translation and rotation of the center of mass.Building upon this foundation,a linearization approach is applied to investigate the UAV’s dynamic characteristics,analyzing the impact of different mass ratios on stability and maneuverability.An optimization strategy for the placement of control mechanisms is presented,and simulation results demonstrate the superior effectiveness of the moving mass control scheme for large-sized UAVs.Additionally,fluid dynamics simulations are conducted using a multiphase flow model to examine the feasibility of amphibious motion for the UAV,and flow field simulations provide evidence of the UAV’s ability to transition between water and air environments.To address the nonlinearities,uncertainties,and excessive overshoot in the control system of the moving mass control coaxial unmanned aerial vehicle(UAV),this study develops a mathematical model and derives the system’s state equations.Qualitative analysis of attitude control and position control algorithms reveals the presence of nonlinearities and uncertainties in the moving mass control coaxial UAV control system.Building on this analysis,attitude and position control laws based on the active disturbance rejection control algorithm are designed for the moving mass control coaxial UAV.The particle swarm optimization algorithm is employed to optimize the complex system parameters.Simulation results demonstrate that the optimized active disturbance rejection control algorithm effectively reduces overshoot and improves the system’s tracking speed.To address the issues of increased overshoot,decreased tracking accuracy,and poor robustness to external disturbances and load variations in the moving mass control coaxial unmanned aerial vehicle(UAV)under load conditions,this study proposes an adaptive fuzzy inference active disturbance rejection control algorithm based on the moving mass control coaxial UAV.In contrast to traditional active disturbance rejection control algorithms,which lack online parameter self-tuning capability,the proposed approach utilizes fuzzy logic to achieve online adjustment of active disturbance rejection compensation coefficients.Additionally,by constructing an adaptive observer for tracking estimation,the algorithm effectively handles the uncertainty associated with the displacement of the load system’s center of mass,thereby enhancing control precision and disturbance rejection capability.The effectiveness and practicality of the proposed algorithm are demonstrated through experimental simulations of load suspension for the moving mass control coaxial UAV in both water and air environments.