Development of an aircraft active sidestick control is an actual direction in modern flight control systems which allows to increase safety, to improve cabin ergonomics and to reduce the mass and weight of control levers. The article devoted to simulation modeling of a pair active sidesticks based on electromechanical actuators coupled by a frameless kinematic scheme, providing identical dynamic characteristics for the pitch and roll channels. MATLAB, Simulink, Simscape, with SimMechanics and SimPowerSystems libraries was used to create the mathematical model. Parameters such as moments of inertia was count based on the 3D model of the active sidestick. The complex model includes two active sidesticks units, three blocks as the input source ("Autopilot", blocks of the 1st and 2nd pilots), a block that compute a loading characteristic for the manual control mode and a block with logic for switching from automatic to manual mode. The model of each active sidestick unit consists of three main blocks: a regulator, an electric motor with a control system, and a block of mechanics. The regulator block includes a PID regulator and a PWM modulator. The electric motor unit includes a power source, a three-phase bridge inverter, a model of a brushless three-phase electric motor from the SimPowerSystems library and a power switch control unit. The mechanics block includes a planetary gearbox, hinge mechanism, handle, moments of inertia, a position sensor, a torsion rod equal to tension springs which are used in device, a nonlinear speed damper and a torque source unit, depending on the force applied by the pilot. Developed model makes it possible to get static and dynamic characteristics of the actuators, to check control algorithms to simulate operating modes in automatic and manual control, including piloting by both pilots at the same time and the interruption in automatic control mode. Including in model a " hold position block" allowed to simulate situation when in manual control mode the 1st pilot tries to hold the handle in a position that he considers correct, despite the intervention of the 2nd pilot. The simulation results showed that developed device meets specified requirements for the aircraft active sidesticks.
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