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This paper aims to propose preliminary design models of actuator housing that enable various geometries to be compared without requiring detailed knowledge of the actuator components. Aerospace actuation systems are currently tending to become more electrical and fluid free. Methodologies and models already exist for designing the mechanical and electrical components, but the actuator housing design is still sketchy.

The approach is dedicated to linear actuators, the most common in aerospace. With special attention paid to mechanical resistance to the vibratory environment, simplified geometries are proposed to facilitate the generation of an equivalent formal development. The vibratory environment imposes the sizing of the actuator housing. Depending on the expected level of details and to vibration boundary conditions, three levels of modeling have been realized.

This paper shows that the vibrations induced by aircraft environment are not design drivers for conventional hydraulic actuators but can be an issue for new electromechanical actuators. The weight of the latter can be optimized through a judicious choice of the diameter of the housing.

This approach is applied to a comparison of six standard designs of linear actuator geometries after validation of the consistency of the different models. Early conclusions can be drawn and may lead to design perspectives for the definition of actuator architecture and the optimization of the design.

This paper has demonstrated the importance of the vibratory environment in the design of linear actuator housing, especially for electro-mechanical actuators with important strokes. Developed analytical models can be used for the overall design and optimization of these new aerospace actuators.

In more than 100 years of aviation, significant progress has been made in flight control systems. The aircrafts that have entered service for the past ten years tend towards power-by-wire flight control with electrical actuators. The purpose of this study is to analyse the effects of electrical actuation on power consumption, weight and fuel consumption on a commercial transport aircraft.

The Airbus A321-200 aircraft was chosen as a case study for analysing the effects of electrical actuation on the flight control actuation system (FCAS) architecture, and Pacelab SysArc software was used for design, modelling and analysis. As alternatives to the existing system, hybrid and all-electric models are built to a set of design guidelines with certain limitations.

Compared to the existing FCAS architecture model, 80 kg weight savings in the hybrid FCAS architecture model and 171 kg weight savings in the all-electric FCAS architecture model were observed. In terms of fuel consumption, it has been observed that there is 0.25% fuel savings in the hybrid FCAS architecture model, and 0.48% fuel savings in the all-electric FCAS architecture model compared to the existing FCAS architecture model at 3200 NM.

In line with the data obtained from this study, it is predicted that electrical actuation is more preferable in aircraft, considering its positive effects on weight and fuel consumption.

In this study, three different models were created: the existing FCAS architecture of a commercial transport aircraft, the hybrid FCAS architecture and the all-electric FCAS architecture. Hybrid and all-electric models are built according to a set of design guidelines, with certain limitations. Then, similar flight missions consisting of the same flight conditions are defined to analyse the effects of power consumption, weight, and fuel consumption comparatively.

The purpose of this paper is to develop accurate model and simulation of mechanical power transmission within roller‐screw electromechanical actuators with special attention to friction, compliance and inertia effects. Also, to propose non‐intrusive experiments for the identification of model parameters with an integrator or system‐oriented view.

At system design level, the actuation models need to reproduce with confidence the energy losses and the main dynamic effects. The adopted modelling methodology is based on non‐intrusive measurements taken on a standard actuator test‐bench. The actuator model is first structured with respect to the bond‐graph formalism that allows a clear identification of the considered effects and associated causalities for model implementation. Various approaches are then combined, mixing blocked or moving load, position or torque control and time or frequency domains analysis. The friction representation model is suggested using a step‐by‐step approach that covers a wide domain of operation. The model is validated under varying torque and speed conditions.

A structured model is introduced with support of the bond‐graph formalism. Combining blocked/moving load and time/frequency domain experiments allows the development of progressive model identification. An advanced friction representation model is proposed including the effects of speed, transmitted force, quadrant of operation and roller‐screw preload.

Mechanical transmission energy losses and dynamics are modelled in a system‐oriented view without massive need to confidential design parameters. Not only speed but also load and operation quadrant effects are reproduced by the proposed friction model. The non‐intrusive experimental procedure is made consistent with use of a standard actuator test‐bench.

The purpose of this paper is to design an electromechanical actuator which can inherently tolerate a stuck or loose failure without any need for fault detection isolation and reconfiguration.

Generalized design methodology for a thrust vector control application is adopted to reduce the design iterations during the initial stages of the design. An optimum ball screw pitch is selected to minimize the motor sizing and maximize the load acceleration.

A high redundancy electromechanical actuator for thrust vector control has lower self-inertia and higher reliability than a direct drive simplex configuration. This configuration is a feasible solution for thrust vector control application because it offers a more acceptable and graceful degradation than a complete failure.

Future work will include testing on actual hardware to study the transient disturbances caused by a fault and their effect on launch vehicle dynamics.

High redundancy electromechanical actuator concept can be extended to similar applications such as solid motor nozzle in satellite launch vehicles and primary flight control system in aircraft.

High redundancy actuators can be useful in safety critical applications involving human beings. It can also reduce the machine downtime in industrial process automation.

The jam tolerant electromechanical actuator proposed for the launch vehicle application has a unique configuration which does not require a complex fault detection isolation and reconfiguration logic in the controller. This enhances the system reliability and allows a simplex controller having a lower cost.

The purpose of this paper is to present a novel approach in aeroservoelastic analysis and robust control of a wing section with two control surfaces in leading‐edge and trailing‐edge. The method demonstrates how the number of model uncertainties can affect the flutter margin.

The proposed method effectively incorporates the structural model of a wing section with two degrees of freedom of pitch and plunge with two control surfaces on trailing and leading edges. A quasi‐steady aerodynamics assumption is made for the aerodynamic modeling. Basically, perturbations are considered for the dynamic pressure models and uncertainty parameters are associated with structural stiffness and structural damping and are accounted for in the model by a Linear Fractional Transformation (LFT) model. The control commands are applied to a first and second order electro‐mechanical actuator.

Dynamic performance of aeroelastic/aeroservoelastic system including time responses, system modal specifications, critical flutter speeds, and stability margins are extracted and compared with each other. Simulation results are validated through experiments and are compared to other existing methods available to the authors. Results of simulations with four structural uncertainties and first order controllers have a good agreement with experimental test results. Furthermore, it is shown that by using a high gain second order controller, the aeroservoelastic (ASE) system does not have any coupling nature in frequency response.

In this study, modeling, simulation, and robust control of a wing section have been investigated utilizing the μ‐Analysis method and the wing flutter phenomenon is predicted in the presence of multiple uncertainties. The proposed approach is an advanced method compared to conventional flutter analysis methods (such as V‐g or p‐k) for calculating stability margin of aeroelastic/aeroservoelastic systems.

In the past electromechanical actuators have been used to operate and control functions that demanded reasonably low power whilst the more arduous requirements of secondary and primary flying control surfaces have been powered by hydraulic motors and drives. With the advent of rare earth permanent magnet electrical machines with greatly enhanced magnetic properties allowing higher powers to be achieved without significant increases in mass and dimension, together with the development of high voltage power electronic devices, it is now possible to extend the application of electomechanical actuation even to primary flying control surfaces. This paper highlights some design aspects in the development of electromechanical actuators (EMA's), draws attention to the several advantages of EMA's and their rare earth drive motors and addresses some of the problems that need to be tackled in order to achieve full certification for future aircraft.

Fault tolerant control surface actuation of unmanned aerial systems with take-off weights below 150 kg offers new design challenges due to limitations in mass, weight and cost. Conventional redundancy concepts need to be amended by smart operational strategies, enhanced sensor data provision and advanced failure mitigation. The paper aims for the design of a hardware-in-the-loop platform that enables the model-based development, verification, performance analysis and safety assessment of redundant and smart electromechanical actuators.

The hardware-in-the-loop platform was developed on the basis of various requirements and upcoming certification needs. One major aspect is the close relationship between model-based design approaches and the ability to keep hardware prototypes in the loop during the entire development process using virtual actuator control electronics.

The platform has proven to deliver valuable results during development of hardware and software prototypes. By its high flexibility and modularity, it has shown to be a versatile, attractive and cost-efficient alternative to conventional hardware-in-the-loop environments.

The presented simulation environment allows operating the components under realistic conditions by offering a control surface setup with redundant electromechanical actuators and a torque machine for hinge load simulation. It supports active–active, active–passive and single actuator operations to examine force-fighting phenomena, performance measurements and the exposure to actuator and control surface hardware faults.

The presented simulation environment provides precise knowledge about the behaviour of all involved components within all states of flight as well as mission and failure scenarios that are required during design, implementation and testing of fault tolerant actuation systems.

The presented paper aims to describe the general idea, simulations and prototyping process of an assisting flight control system (FCS) for light sport aircraft (LSA). The proposed FCS framework is intended to simplify piloting, reduce pilot workload, and improve system's reliability and handling qualities of manual flying.

Assisting flight control strategy integrates mechanical and digital FCS into a synergic platform, combining the high reliability of mechanical controls with the computation and actuation power introduced through a single line digital FCS. Concepts drawn from classical control theory along with flight envelope protection algorithms have been used throughout the design of the flight control laws. A prototype of the assisting FCS has been subjected to validation trials during series of hardware-in-the-loop simulations.

Despite controversies between the pilots' perception of a modern aircraft and limitations imposed by the legacy airworthiness codes, it has been shown that a pilot assisting and workload reducing control system can be successfully implemented on board of a LSA while satisfying the expectations on a state-of-the-art equipment meeting required level of safety defined by the current legislation.

A transition between specific flight modes as well as nonlinearities in the FCS may lead to unfavorable and unpredictable forms of aircraft-pilot interactions. The number of accessible flight control modes should be therefore limited to the most significant ones.

Sport aircraft are mostly flown by a single pilot, who could benefit from the pilot assisting FCS as the system has the potential to supervise the aircraft's safe operation in various flight conditions.

Introducing an assisting FCS on board of a LSA through an innovative approach which utilizes hidden and unused resources of modern digital automatic FCSs while respecting the limitations imposed through the weight and cost sensitive nature of the LSA market.