Study of the design parameters of the onboard system for changing the mass-inertia characteristics of the aircraft

The paper presents the results of a study of a new concept of a system for changing the mass-inertial characteristics of nominally axisymmetric rotor structures, in particular, aircraft of an axisymmetric shape. This system can be used for static and dynamic balancing of the product directly during operation and is a balancing weight installed on the movable platform of the mechanism with parallel kinematics of the hexapod type. It can be applied, including for nominally axisymmetric aircraft, to parry disturbances from asymmetries of various kinds by purposefully creating a mass-inertial asymmetry of the structure. The paper analyzes the ways to bring the system to the required state (by linearly changing the lengths of the drive rods, as well as by moving and rotating the balancing weight according to linear laws). The ratios of the mass-inertia characteristics (longitudinal and transverse moment of inertia of the balancing weight) of the “body of the aircraft - balancing weight” system and their influence on the kinematic parameters of the mechanism, in particular on the required displacements and rotation angles of the balancing weight, the magnitude of the change in the lengths of the drive rods were evaluated. Based on the original model as a system of two bodies “body of the aircraft - balancing weight”, an extended model was created taking into account the mass-inertial characteristics of the drive rods. The applicability of the two-body model is analyzed depending on the mass-inertia characteristics of the drive rods, in particular, on the mass of the rods. The influence of the accuracy of changing the lengths of the drive rods on the final mass-inertia characteristics of the system, such as the axial moments of inertia of the system and the residual uncompensated centrifugal moment of inertia, is analyzed.