This project made a key contribution to the AEA through the development of novel simulation models for the quantitative evaluation of the mechanical, electrical, and thermal behaviour implied by the use of EMAs.
This goal was achieved via innovative developments on different levels.
- Firstly, the physical-mathematical models of both the EMAs and the FCS/LG was set-up in such a way that they can be interlinked through the exchange of common parameters, typically EMA-positions and aerodynamic forces/torques.
- Secondly, the individual components were integrated into a single simulation model, which directly interfaces with the Shared Simulation Environment (SSE) of AEA, GRA3.
- Thirdly, test scenarios were defined, which are adequate for the validation of the electro-mechanical and electro-thermal outputs.
The electro-thermal data involved in these test scenarios differs from that normally considered for mechanical/hydro-mechanical systems. To ensure that the simulation models can readily be integrated into existing aircraft concepts and simulation tools, standards were used wherever possible.
E-Bird developed a Modelica Library to simulate electromechanical actuators (EMA) with a high level of physical realism. These EMAs can be used in many application models. In order to evaluate the EMA models directly and also for use in the Green Regional Aircraft Integrated Simulation Environment, three application models, one for a typical aircraft main landing gear (MLG) one for a typical nose landing gear (NLG) and one for an all-electric flight controls system (FCS) consisting of ailerons, flaps, spoilers, elevators and a rudder have been designed. For each of these models a simulation test bed is included in the library so each component and each setup can be tested. The library is subdivided into three packages, which contain the EMA, LG, and FCS models. Although the EMAs form a component of the MLG, NLG and FCS systems, they have been placed in a separate package to facilitate the development process of Bausch-Gall (responsible for EMA) and TWT (responsible for LG, FCS). The Electromechanical Actuators package contains individual models of EMAs. The basic EMA model is the same for all of the variants, however parameters relating to delivered torque, gear box and controller are different and tailored to their designated application. The naming of the models reflects their application (i.e. ElectroMechanicalActuatorSpoiler). There is also a simple EMA model with a much reduced complexity of modelling. The details of each of the model classes are explained in the Modelling Manual.
The Models themselves are developed from the components in the corresponding EMA Components package and standard Modelica library classes. For each of the Components dedicated test models exist.
The final output from EBird is a library of modelica models for EMAs and LG/FCS assemblies. These models are already used in the CSJU project iSSE in the full electrical system simulation of the GRA ITD. The project has been presented in a paper at the 2013 Airtec fair with good response from the audience and TWT GmbH and Bausch-Gall GmbH both expect that the models find widespread use in the optimisation of power consumption and design of green regional aircraft.