OBJECT-ORIENTED MODELLING OF FLIGHT CONTROL ACTUATION SYSTEMS FOR POWER ABSORPTION ASSESSMENT

In the work, the object-oriented approach provided by the Modelica-Dymola environment is used to perform a comparison between different technologies for aircraft actuation systems in terms of power absorption characteristics. Starting from the same set of basic design, three actuators characterised by different technological solutions (servohydraulic, electro-hydrostatic and electromechanical) have been defined, and the related “object-models” have been developed and characterised in terms of dynamic performances. In parallel, the model of a basic flight control system with two ailerons, two elevators and one rudder has been created, including models for the aerodynamic hinge moments calculation and the simulation of elasticity of the actuator structural links. The models have been then used to obtain three types of actuation systems: a traditional servohydraulic one, a “more-electric” plant with all electro-hydrostatic actuators, and an “allelectric” system. Each system is finally tested with the same command time history by reproducing a sample flight manoeuvre, and the power absorption characteristics are analysed and discussed