Research On A 3PSS+S Parallel Driving Device Of Helicopter Main Rotor

Among aviation vehicles,helicopters are widely used in various fields of military and civilian use due to their high maneuverability and efficient hovering characteristics.As the core of helicopter power and control,advanced rotor drive devices have become the focus of domestic and foreign research.This subject researched a new type of helicopter rotor parallel drive device,replacing the traditional helicopter’s automatic tilter with 3PSS+S parallel mechanism,and using the parallel mechanism’s high rigidity and multiple degrees of freedom to further improve and improve the performance of the drive device.Compared with the traditional helicopter drive device,the main advantage of the new parallel drive device is that the structure is simpler and the waste resistance area is reduced;the flexible drive is adopted to prevent the engine main shaft from swinging with the helicopter’s main rotor shaft;the device structure is a parallel mechanism with greater overall rigidity.The main research content of this topic can be divided into the following aspects.The degree of freedom of the parallel mechanism is calculated and verified,and the inverse position solution of the mechanism is solved based on the vector method.Based on the projection method and the influence coefficient method,the Jacobian matrix and the Hessian matrix of the mechanism are solved,and the velocity and acceleration relationship between the input and output of the mechanism is established.The method of combining the virtual work principle and Newton-Euler method is used to solve the statics and dynamics problems of the mechanism,and the mathematical relationship between the driving force and the load is established.Combining the principle of virtual work and material mechanics,the stiffness matrix of the mechanism and the deformation of the center point of the moving platform are obtained,the stiffness model of the mechanism is established,and the trajectory of the driving device is planned according to the stiffness and deformation.In the Matlab/Simulink software environment,the simulation model of the parallel mechanism is constructed,and the three-dimensional entity model of the mechanism is established by Solidworks.The two are combined to verify the mathematical model.Based on the blade element theory and the rotor vortex theory,the force of the rotor and the helicopter flight power during flight are solved.Combined with the dynamic calculation results of the device,the relationship between the rotor pull and the load of the ball pair is established and the finite element simulation of the ball pair is performed,which provides a theoretical basis for the practical application of the mechanism.