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ACTUATION 2015: Modular Electro Mechanical Actuators for ACARE 2020 Aircraft and Helicopters

Final Report Summary - ACTUATION2015 (ACTUATION 2015: Modular Electro Mechanical Actuators for ACARE 2020 Aircraft and Helicopters)

Executive Summary:
The All-Electric Aircraft is a major target for the next generation of aircraft to lower consumption of non-propulsive power and thus fuel burn. To eliminate hydraulic circuits, pumps and reservoirs, Electro Mechanical Actuators (EMA) are mandatory but now need to meet cost, reliability and weight requirements from the airframers.
ACTUATION2015 aimed to develop and validate a common set of standardised, modular and scalable EMA resources for all actuators (flight control, high lift, main landing gear, door, thrust reverser) and all types of aircraft (business/regional/commercial airplanes and helicopters).
Compared to an A320 aircraft, ACTUATION2015 targeted a reduction of the overall Life Cycle Costs of actuators of 30%, to improve reliability by 30% and to reduce aircraft weight by 500kg.
ACTUATION2015 was a 4.5-year integrated project comprising 54 partners representing the European stakeholders of the actuation and airframe sectors from 12 countries.
The technical approach has gathered detailed airframes’ requirements, specified a set of standard modules, and developed prototypes for assessment at component and actuator level through rig tests and the virtual validation of modules. In parallel, a unified EMA design process supported by standard methods and tools was also developed.
The project relied on recent advances made in EU and national projects to integrate the required technologies (solid state power distribution, power electronics, operation in harsh conditions, jam tolerant EMAs, etc.) to overcome the current barriers and to mature the EMA technologies to TRL 5. Four actuators and ten modules were delivered.
Standardising EMA modules (motors, power drive electronics, mechanics, sensing) is seen as a key enabler to succeed in achieving the cost objectives and developing new specifications for use by the supply chain. Standardisation was conducted with the support of a recognised standardisation body (CEN) and led to the publication of CEN workshop agreement, a limited-consensus document agreed by the partners.
ACTUATION2015 has complemented existing EU funded projects, notably CLEAN SKY SGO, with an EMA solution and paves the way towards the ACARE 2020 All-Electric Aircraft.

Project Context and Objectives:
Project context
In recent years, several collaborative research and development projects and industrial programmes started to develop the All-Electric Aircraft (AEA) that provides an opportunity of value change.
The aero-equipment industry has in particular launched several studies and developments on more electrical actuation with Electro Hydraulic Actuators (EHA) or Electro Mechanical Actuators (EMA). This has provided incremental approaches to address hydraulic circuits issues with Fly-by-Wire technologies (A320, B777 and Falcon 7X) and the introduction of 2H/2E architecture for back-up actuators in the A380. The POA FP5 project and more recently, the MOET FP6 project, by moving from Fly-by-Wire (FbW) to Power-by-Wire (PbW) technologies, have demonstrated on specific systems the effectiveness of electrical actuation with:
- Reduction of maintenance operations
- Reduction of leakage-related problems
- Health and usage monitoring system capability
- Time effective assembly and tests
- Improved availability and operation in Aircraft
The resulting More Electric Aircraft with PbW actuators is an answer to limit the proliferation of hydraulic circuits. EMA systems are the best candidate for the aircraft of the future (i.e. the All Electric Aircraft) when considering they are:
- Less complex because of the absence of hydraulic system
- Stiffer than an equivalent EHA since there is no hydraulic fluid in the load path
- Better suited to long term storage or space applications since there is no leak potential
Furthermore the acceleration of EMA entry into service is a necessary technical breakthrough if EU aero-equipment industry wants to remain competitive: newcomers are entering the actuator and aircraft market: FbW is now being developed at low cost (China with COMAC, Brazil with Embraer, Russia with Irkut).
But, technological, economical and safety barriers still persist for a wide adoption of EMA especially when considering:
- Cost issues: EMA cost drivers fixed by the airframers are not reached in the present situation. This EMA cost non-competitiveness is a blocking situation, coming from:
- Specific costly tailored products with single-sourcing and low scale volume
- The lack of standard methods to design, test and qualify EMAs
Standardisation of components and “Design to cost” approaches are essential to make the electrical actuation cost effective. Generalisation of electrical actuation on board increases components production volumes. The definition of families among the electrical and mechanical components, the standardisation of interfaces, the design of Standard modules and the “Resources sharing” of equipment between systems are key factors to reducing the cost of EMAs. “Resource sharing” in the context of the project refers to the multiple, synergetic use of components (e.g. use of the same PDE) for different aircraft functions.
- Reliability issues: EMA sensitivity to certain single point of failures that can lead to mechanical jams, results in a reluctance to mobilise EMA for safety critical applications, and thus creates difficulties for certification of Power Drive Electronics, Motors and Mechanics, and the reliability in harsh environment has to be improved. New power components (e.g. silicon carbide for power control), improved thermal management, more electronics integration (e.g. control card FPGA) and improved mechanics (e.g. lubrication concepts) are essential to meet the reliability requirements. Standardisation is needed to solutions affordable.
- Weight issues: the current technology in use for the development of EMAs is not optimised in terms of weight due to materials, architectures and sensors not being fully optimised and not using latest state-of-the-art technologies (FP6 projects: MOET, DRESS; ...) used expensive for custom made SiC ASICs. EMA technologies were not considered mature enough in 2007 to be part of the JTI CLEAN SKY programme. Recent advances in jam free EMAs and power electronics made at research level (CREAM FP7 project) need to be adapted for aerospace applications at the systems level.
Consequently, to enable the production of future all-electric aircraft in line with ACARE 2020 objectives and to complete the work done in Clean-SKY SGO ITD on the optimisation of more electrical systems architectures focusing on the total deletion of hydraulic circuit, ACTUATION2015 came at the right time for the actuation industry to exploit these recent advances and to overcome these last barriers by developing, integrating and validating the expected low cost electrical modular actuation technology with:
- Standardised modules (e.g. motors, sensors, connectors, screws, etc.) and interfaces to develop cost effective and reliable EMAs, accurate for all systems (including safety-critical systems), applied to all aircraft systems and to several market segments (helicopters, business aircraft, regional and large aircraft),
- Standard design, qualification and simulation tools with qualified processes and model library including in particular a design-to-cost approach (see figure 1).
Achieving the corresponding breakthrough by providing:
- Cost reduction, reliability improvement and weight reduction and power consumption reduction
- Maturity Technological Readiness Level (TRL) ranging from 3 to 5
- Completing CLEAN SKY SGO with the introduction of EMA technologies

Objectives and Results
The aim of ACTUATION2015 was to develop and validate standardised, modular and mutualised EMA for the first time for all airframe systems (flight control, high lift, main landing gear nose wheel, door locks, etc...) and to address the needs of regional and large aircraft, business aircraft, and helicopters.
The ACTUATION2015 technical objectives were to:
- Reduce the overall Life Cycle Costs (LCC) (development, acquisition, certification, maintenance, operation) by:
- Providing standardised families of EMA modules usable in different types of applications and in some cases sharable between different applications
- Designing and producing EMAs from off-the-shelf standardised modules
- Addressing all types of aircraft systems and aircraft applications – from helicopters to large aircraft
- Standardise and reduce the number of qualification and re-qualification tests
- Reduce EMA weight and improving reliability by:
- Introducing new materials, (e.g. Sic for electronics, magnetised composites for motors, ...)
- Mutualisation and optimisation of actuation architectures
- Enabling an all-electric architecture at aircraft level
- Improving safety margins by developing health monitoring techniques to predict the onset of failures
- Maturing the Technology for deployment in the next generation of short/medium range single aisle aircraft by 2020

Targeting TRL5 and building on the POA and MOET results, ACTUATION2015 has delivered:
- Standards and modular EMA products, tools and methods ready to use with the output of CLEAN SKY SGO
- New mature actuation technologies (TRL 5 modules):
- Improved sensor technologies
- New control and power management techniques
- Standardised and enhanced Health and Usage Monitoring
- Common standards and Shop Replaceable Units (SRU) or Line Replaceable Units (LRU):
- Motors, sensors, Power Drive Electronics (PDE), power drive systems
- Commonality and scalability in qualification process, providing credit for certification:
- Qualification methods
- Data base on components technologies and processes
Three types of modules applied to several systems were developed and used to validate:
- Concept of modular and scalable standard component applicable to several actuator systems (flight controls, high lift, landing gear, thrust reverser and doors), and also applicable to different type of aircraft (from helicopters to business aircraft and regional aircraft up to large commercial aircraft)
- Low cost and mature actuation technology for flight control systems
- Overall weight, operational reliability, installation and maintenance benefit at a global level of electrical actuation solution
- Global validation of electrical actuation standardisation process
On the basis of aircraft currently into service (optimised short range aircraft – Airbus A320), the results, with this new generation of actuation systems, were:
- A 30% LCC benefit split as follows:
- Savings on each items at actuator family by using the same mechanics, Power Control Module or Control Monitoring Module, Sensors
- Savings from development of components families with various functions provided by the same/similar hardware
- Savings from reduced cost of modification/retrofit/obsolescence management which are applicable to larger components units engaging significant cost scale reduction,
- Installation and maintenance cost reduction for airframers assembly line and airlines maintenance with:
Reduced Initial provisioning for actuators by reducing the amount of different part number “modules” for the same family of actuators
Electrical actuators “Plug and play” principle (no bleeding, no refilling, no leakages)
Improved trouble shooting with electrical actuation and digital communications
Electrical actuator health monitoring to anticipated removals, logistics and stocks optimisation
Pipe installation deletion from final assembly line - assembly time reduction
Deletion of hydraulic tools, ground parks and phosphoric esters storage
- A 30% operational reliability per 10,000 aircraft take-offs
- A 500kg weight saving, made up of various items such as, hydraulic circuits deletion, EMA weight reduction, mutualisation of components, more integrated PDE, etc.
Overall, ACTUATION2015 has significantly reduced the LCC (Life Cycle Cost) of electrical actuation (i.e. acquisition, certification, maintenance and operation costs) while contributing to maturing the technology, improving the reliability and reducing fuel consumption through weight savings.

Project Results:
SP1: Specifications for modular EMA

SP1 partners have applied a multi-disciplinary integrated approach gathering airframers, actuator manufacturers, component suppliers to define electronic modules covering a large amount of electrical actuators applications:

• Multi-system applications within a given functional area of the aircraft (ATA chapter classification; e.g. ATA-32, landing gear: braking, steering, gear actuators).
• Trans-ATA applications: modules utilisation across different system domains (e.g. landing gear and flight control actuators electronics).
• Multi-aircraft applications: modules compatible for a wide range of aircraft (regional, short range, long-range and large aircraft).

This approach was followed iteratively through a number of steps:

1. Requirements collection by airframers (Airbus, Alenia, Piaggio and Airbus helicopter) for the various aircraft applications.
2. Standardisation of the actuator sensors interfaces, motor sensors interfaces, aircraft communication and power interfaces.
3. Pre-sizing of each EMA by the actuator manufacturers with a bespoke design. Definition of module capacities and ranges.
4. Workshops to determine the best electronic modular architecture solution considering the aircraft optimum and the systems specifics.
5. Specification of the standardised electronic modules.

Some features of the Power Drive Electronics (PDE) allow tailoring it to each specific application. This includes: casing, thermal management, mechanical support, electrical connections between the modules, filtering, lightening protections, electro-magnetic protection and custom functions that are unique to each EMA type.

One of the main challenges for SP1 partners was to define an architecture using widely accessible and well-proven technology.
The determination of the optimal modular system has proven to be challenging: on one hand electronic modules should be versatile enough to cover the needs of the most demanding applications; on the other hand the chosen solution must not be too oversized for those applications with lower requirements.

The key modules for the electrical aircraft actuation electronics are:
• Power Core Module (PCM).
• Control & Monitoring Module (CMM).

PDE design guidelines have also been used to specify the internal low voltage power supply (Internal Standardised Supply Interface – ISSI), the protocol for Inverter Control Over LVDS (PICOL), the motor and actuator sensors interfaces, the data-logging NVM protocol and the standardised Operating System for software download onto the CMM.

The concept of EMA and EHA are identical with the exception that EHA uses fluidic gearing between the electric motor and the surface actuator instead of mechanical gearing.
ACTUATION2015 partners have therefore taken into account the requirements of EHAs in the standardisation process of actuator electronics. The PDE comes in different configurations to meet the varying needs of applications:

Primary Flight Controls (e.g. aileron, spoiler, elevator, rudder).
In the configuration intended for primary flight control (PFC) the PDE contains two standardised CMMs – one of them carries out a Command Lane (COM) and the other a Monitor Lane (MON) – and one standardised PCM.

Secondary Flight Controls (e.g. High-Lift System)
The HLS actuator is powered and controlled by two independent PDEs. As for PFCs, each PDE contains two CMMs for control and monitoring and one PCM for power control. The electrical motor is a dual-wound machine rather than two separate motors in order to optimise weight, cost and space.
The same PDE configuration is applicable for the Trimmable Horizontal Stabilizer.

Landing gears: Steering and Braking systems.
The steering PDE is identical to a primary flight control PDE: two CMMs for control and monitoring and one PCM for power control.
A braking PDE contains 4 PCMs for 4 actuators power control and 2 CMMs. A single CMM manages two PCMs via the digital interface (PICOL). Same topology is applicable for several flight control surfaces control with the same CMM (e.g. Spoilers multiple control).

AAEM/FNM: Regional aircraft electrical actuators requirements (WP13)
The main objective of this WP was to provide specification requirements for Flight Control Primary Actuation System, for Landing Gear Actuation System, High Lift Actuation System, for Cargo Doors and Thrust Reverser Actuation System for regional aircraft (< 100 seats), as well as to capture electrical requirements of more electric scenario and define constraints and guideline for electric actuation.
Regional aircraft are a relatively wide segment in civil aviation, with weight configurations that may vary from 15 tons to 50 tons and more. Potential applications for electrical actuation are therefore quite large for every individual application on aircraft even if considering regional aircraft alone. Hence, requirements have been collected by taking into account different applications within the same segment.
The baseline aircraft that was considered for this work is a regional twin-engine turboprop that is currently of interest for future development. This aircraft is presently confined in a conceptual/definition phase. The aerodynamic configuration is a traditional one, i.e. one Rudder for Yaw control, two Elevators for Pitch control, and two Ailerons for Roll control. This particular baseline comprehends a pair of multifunctional Spoilers (two on each side of the wing), all acting as Roll control and ground braking/lift dumping.
During ACTUATION2015 Project it has been designed an Elevator EMA. The Elevator actuator has been chosen for virtual integration because of the challenging space envelope requirements, compared to the Aileron or Rudder ones. Elevator actuators are installed in the stabiliser trailing edge, where the airfoil absolute thickness is smaller than in the fin (where Rudder actuators are installed) or even in the wing (where Aileron actuators are installed).
The Elevator EMA pre-sizing results in an actuator that fulfils the main installability requirements, even if it leaves some development open to improvements, for example rearrangement of the EMA configuration, in terms of relative position of its elements (motor, gear, screw), can be optimised in order to get some better installability.

Several other potential installation improvements are possible by reconsidering some Specification requirements in addition to details of EMA components integration. The used pre-sizing tool gives a reasonable result, but it is recommended to harmonise tool input parameters with specification requirements.

SP2: Technology modules
SP2 partners have developed the required technology to meet the cost, reliability and weight project key targets. Also it has been addressed technology works related to hardware EMA modules including: motor architecture, composite materials, mechatronics, new sensors, power electronics, while applying the standardisation process and using the tools from SP3 and SP4. SP2 have designed and manufactured three types of modules which have been used for integration in SP5 and testing in SP6.

Mechanics and materials (WP21)
Mechanical transmission systems have been optimised and it has been proven a significant reduction of the probability of jamming for safety-critical applications (jam-free approach). Also, the wear of mechanical components has been minimised with the development of new lubrication concepts which improve failures rates, reduce maintenance and extend component life of EMA.
New materials have been characterised and validated such as advanced composite and specific stainless steel, in order to address cost, reliability, life and weight issues on the basis of specifications provided by SP1, thermo-mechanics rules and environmental constraints.
Jam tolerant designs and devices have been proposed which are incumbent to some applications.
It has been established a new set of standardised process for design, sizing and qualification of key components of the mechanical drive train like roller screws and ball screws, considering specific requirements with respect to dynamic loads,
vibration and harsh environment.

Sensors (WP22)
The main objective of WP22 was to develop and validate standardised sensors for EMA for all airframe systems (flight control, landing gear, thrust reverser and doors. Specific technical objectives were:
• To develop standard processes on selected module on the last state of art of sensor without contact.
• To demonstrate that the modules selected on linear and on rotary equipment are the best choices and that it will provide cost efficiency.
• To show that a new technology approach with the sharing of several functions in the same sensor module is possible and can follow the standard processes. Introducing new technologies and developing new optimised architectures.
All of the above objectives have been achieved and documented.

Motors (WP23)
During the project it has been developed a family of scalable electrical motor modules for the construction of aircraft actuators usable in various aircraft applications addressing factors such as cost, high reliability and high torque density and fulfilling SP1 standardisation requirements.
The optimisation of these modules has been done using different motor technologies and assessing three main concepts:
- Simplex motor without any inherent fault tolerance: two simplex motors may be used in parallel inside the actuator in order to meet aircraft safety and reliability requirements.
- Dual winding motor: a dual lane motor consists of a standard rotor and a stator with two separate windings.
- ‘Fault Tolerant’ motor: a motor that includes a level of inherent redundancy, therefore potentially reducing the mass, space envelope and cost of multiple redundant actuators.

A standard motor module in two copies has been manufactured by two different partners in order to demonstrate their interchangeability. These modules have been validated on a test bench in SP6 and integrated in SP5.

SAGEM: Power Drive and Mechatronics (WP24)
The objective of this WP was to develop a modular and standard Power Drive electronic, able to address different actuation configuration on an aircraft.

Main Key Design Drivers were centred on availability, space envelope /weight and cost.
The development (including the trade-off studies and the specification completion) has been performed by the partners of this WP in a fair way, and a clear willingness to succeed.

According to the DOW, the following activities have been achieved:
• Common specification for A/C PDE
• Standardisation of Command Monitoring Module, Power Core Module, Mechanical and Electrical interfaces (for internal as well as external connections)
• Standardisation of Software packages (OS, AS) as a first step towards a final standardisation objective
• Allowing the initiation of the normalisation activity (see WP72)
• Manufacturing and unitary tests of the modules with demonstration of expected performances (partial due to schedule constraints)

As main results to be recorded for this WP, we may highlight:
• The modularity concept demonstrated at PDE level
• The compliance with technical requirements at A/C level (fixed wings and rotary wings)
• The compliance with economic targets at A/C level (see WP63)
• The validation of an important technical step on the roadmap for Smart Power Electronics and more ambitious targets in terms of availability-reliability/ space envelop/ weight/ cost.

SP3: Methods and Tools
The general aim of SP3 was to develop, implement, and demonstrate methods and tools able to accelerate the design and development process of electromechanical actuators for any application in passenger aircraft. Three main objectives were pursued along the project and successfully fulfilled:
1. Development of efficient methods for the design and optimisation of EMAs
2. Creation and validation of a standard-multiphysics model library of EMA components
3. Generation of a process to enable EMA modular certification and virtual testing
All methods developed were tailored to EMA applications and designed to meet the engineers’ needs. A lot of effort was put to demonstrate and validate the created methods and models as it was recognized from the beginning that this is a major driver for the industrial utilization of such. The advancement in terms of model-based methods and tools for the design of EMAs in comparison to the status at the beginning of the project can be summarized as follows:

• Reduced number of key parameters for an optimal design of EMAs,
• Multi-level models with increasing simulation performance
• Highly automated sizing process without sacrificing accuracy,
• Less demanding iteration loops,
• Modular and component oriented model libraries,
• Numerically robust, well documented, and easy-to-parametrize models,
• Standard model library is at the disposal of all partners and will become soon a commercial product.

Furthermore, relevant investigations were performed on the stability and regeneration aspects of different actuation systems and power system configurations. These led to a set of conclusions with direct impact on the future use of EMAs in combination with a HVDC power supply.

Reliability and Uncertainty Analysis (WP33)
A suite of tools for performing uncertainty and reliability analyses at two different levels – actuator and flight control system level – were developed and tested with real applications. The outcomes of this work package are: the required reliability information to perform case studies, the methods behind the tools, and the conclusions and recommendations drawn from the investigations performed. These outcomes are namely,
• A database containing safety and reliability information for electromechanical actuator components,
• A tool based on Bayesian Networks for propagating uncertainties in reliability values of actuator sub-components into system-level reliability analyses,
• A method and tool to perform model-based reliability analyses at actuator and flight-control system level,
• Application of the developed tools leading to a set of conclusions on the reliability of primary flight control systems with electromechanical actuators,
• Evaluation of different reliability tools and comparison against the developed ones.
Although the tools created in the framework of this work package were not put at the disposal of partners outside SP3, the contribution resides in the general approach and methods employed to study the reliability of electromechanical actuation systems in an efficient manner.

EMA Validation, Testing and Certification (WP35)
The partners of WP35 developed a view on how to validate, test and certify modular EMAs. The modular certification process was described in D35.1. The role of virtual testing in the qualification process was investigated and described in D35.2. The benefits of health monitoring for qualification of EMAs to be expected were searched for and were reported together with health monitoring qualification and certification aspects in D35.3. Generic test plans and test procedures for EMAs and EMA modules were compiled in D35.4 respectively D35.5. And the process description for the qualification of EMAs is given in D35.6.
The partners in WP35 were Airbus Group Innovation, INSA Toulouse, Paragon, Hamburg University of Technology, Technical University of Munich and NLR. The academic view was therefore prominent amongst the partners. The views were an important input for WP64 where industrial partners generated their view on optimised qualification of EMAs and EMA modules including the certification aspects.

SP4: Control and Monitoring
The main Scientific and Technical (S&T) results for SP4 are fully described and documented in the SP’s formal reports (20 off) that have been delivered to the EC.
SP4 was made up of three work packages (WP) that addressed three distinct areas of research relating to control and monitoring aspects of the ACTUATION2015 EMAs.

Fourteen partners, from nine different countries, contributed to the work that was performed. The team was made up of 6 industrial partners, 1 academic partner, 5 SMEs and 2 research institutes.

WP41, titled “Prognostics and Health and Usage Monitoring” (PHM), which had thirteen partners, was concerned with the study of possible ways and means to determine the heath of the ACTUATION2015 EMAs with the primary objective of being able to determine remaining useful life (RUL). Knowledge of RUL for the actuators is useful to enable preventative maintenance actions to be carried out in a timely manner and thereby reduce the occurrence of in-service failures. Remaining useful life can be a function of both actuator usage and degradation that occurs as a result of failures. Hence the WP addressed both aspects.
The results that were produced included a definition of a PHM system level architecture, including aspects related to the health and usage monitoring of individual actuators as well as the management of health and usage information at both the aircraft level and the fleet level. Actuators are repairable items and may be installed on different aircraft throughout their life. Hence it is necessary to have methods to manage the health and usage data throughout the life cycle.
A number of different methods and algorithms for assessing both the heath and the usage of the EMAs were developed and assessed and the results documented. These included fault detection methods for the individual EMA components (motors, bearings, gearboxes, etc.) as well as methods for assessing the performance of a complete EMA. Of particular note was the development of a novel condition based monitor for detecting motor faults. It did this by looking for changes in the motors magnetic signature. A low voltage carrier signal was added to the motor drive signals and this was used to detect variations in the reactance modulation. The technique also generated a synthetic rotor position signal and this was evaluated as part of a sensorless control scheme in WP42.
Finally, a new data driven health assessment method was developed that will allow RUL estimates to be generated without the need for expensive run-to-failure tests to be carried out on the individual EMA components. WP41 produced 11 deliverable reports.

WP42, titled “Advanced Control and Monitoring”, which had seven partners, was concerned with the development of advanced control and monitoring techniques related to the use of the ACTUATION2015 EMAs in their intended applications.
The results that were produced included the assessment of advanced design methods and tools to determine the optimum performance and stability criteria and to perform “what if” parameter analyses to determine key sensitivities for different options.
The work performed included the development, analysis and assessment of various control law strategies for EMAs configured in a redundant force summed active/active configuration taking into account both normal operation (fault free) as well operation in the presence of failures. For example, a number of different fault tolerant control schemes were developed that were able to provide continued operation in the presence of a detected failure e.g. a sensor fault or motor winding fault.
Some faults result in failures that have to be detected and passivated very quickly. A particular case that was studied was that of a powered EMA runaway. This failure has to be detected and isolated before the fault has an effect at the control surface. An algorithm to detect and isolate the ‘failed’ EMA was developed and tested.
Finally, software functional specifications were written for a sub set of the control and monitoring schemes that were evaluated. This was done to facilitate their implementation (for practical evaluation) on the ACTUATION2015 EMAs. WP42 produced 5 deliverable reports.

WP43, titled “Regenerated Power Management”, which had three partners, was concerned with the management of the power that can be regenerated by an EMA during normal operation. This power, if not managed properly, can “pump up” an EMA’s bus voltage to a level that will result in malfunction or damage to the EMA.
The management of regenerated power (to date) has typically been performed local to each individual EMA (in the EMA control electronics).
The ACTUATION2015 project took the decision to allow each EMA to put regenerated power back onto its HVDC supply bus, thus moving the problem of managing this power onto the power generation/power distribution network.
Moving this function away from the EMAs has the benefit of reducing the weight and volume of the EMA control electronics. Local management of regenerated power normally takes the form of dissipating (dumping) any excess energy across a load resistor.
The study carried out in WP43 looked at a number of different options including ‘dumping’, ‘storing’ and ‘consuming’ excess energy. Architectural considerations looked at various options including: managing re-generated power local to a group of co-located EMAs, managing re-generated power for a group of EMAs connected to the same HVDC supply, managing re-generated power for each EMA individually at the point of power distribution.
The results of this activity include a set of requirements for the management of regenerated power, the identification of the full range of possible architectural options for managing regenerated power, the creation of various simulation models and the system level assessment of the most promising candidate solutions.
The study identified a number of possible solutions and these were ranked in terms of preference; albeit there wasn’t a clear winner in terms of a single ‘best solution’. In practice, different solutions may be applicable for different aircraft, depending on the electrical infrastructure (i.e. power generation and distribution) that is installed.
The final report for the activity included a summary of the key results obtained, a set of recommendations for the way forward, and proposals for possible future work activities in this area. WP43 produced 4 deliverable reports.

SP5: Modules Integration
The aim of SP5 is to prove on real applications the modularity and scalability concept developed in the previous SP. This demonstration addresses at the same time the major actuators on an aircraft:
- Permanent actuation (i.e. power needed during the whole flight) such as Primary Flight Control, Nose Wheel Steering - WP52
- Transient actuation (i.e. power needed for a limited time during the flight): High Lift, Trimmable Horizontal Stabilizer, Main Landing Gear extraction and retraction, Nose Gear retraction, Cargo Doors and Thrust Reversers - WP53
- Pulsed actuation (i.e. power needed for a very short time during the flight): lock – WP54

The development of this set of actuators was based on the work carrier out into the others SP:
- Actuators requirements issued in SP1:
The iteration loops between airframers and equipment manufacturers, carried out in the scope of SP1, to define the best modules sharing led also to optimize the actuators specifications used for virtual and hardware integrations developed in SP5.
- Standard modules developed in SP2,
- Simulation models developed in SP3:
Some virtual integration (PFC for helicopter, PFC for Business and Regional for example) started later in the project. For this reason they could take full profit of the models, tools and methodology developed in SP3.

The standard modules approach has then been validated on:
- Real hardware demonstrators:
Four actuators for permanent and transient applications on commercial aircraft have been selected as the most representative. Aileron, spoiler, High Lift and braking actuators have then been designed, manufactured and tested.
- Virtual demonstrators:
A total of nine actuators for permanent, transient and pulsed applications have been studied up to a level of maturity close to TRL3: Main Landing Gear and Main Landing Gear Door extension/retraction and locking, THA, Helicopter Secondary Flight Control, Primary Flight Control for regional and business jet.

As a conclusion, it has been stated that:
- EMA could fit for all these applications,
- Electronic standard modules can be used by roughly all the A/C selected applications,
- All the standard electronic modules identified in SP1 and SP2 (CMM, PCM, ISSI, PICOL, etc.) can be used with great advantages, particularly for braking system,
- Aileron and spoiler actuators can use standard mechanical modules (roller/ball screw, rotary gearbox, and sensors), standard motor,
- Actuators for High Lift or Braking systems are too specific to integrate mechanical or electromechanical standard modules,
- Mechanical parts particularly for low leverage applications (THSA, Landing Gear for example) are generally too specific and cannot be standardised.

Based on these promising results, the detailed characterisation of the performances of these demonstrators will be carried on after the end of ACTUATION2015 project. These tests results on system and on standardised modules will be used as inputs for new National or European projects dedicated to more electrical aircraft.

SP6: Validation
This SP has been one of the most critical of the project; especially because it has collected the work achieved in other SPs and WPs and had the goal to assess the activities performed and the ambitious results targeted.

According to the DOW, the following activities have been achieved:

• Development and manufacturing of a modular test bench
• Execution of a full batch of tests on unitary modules and sub-assemblies
• Assessment of modular concept at actuator level,
• Assessment of economic and technical impact of modular and standardised EMA
• Generate a standard Test Plan and Certification process, with related assessment.

As main results to be recorded for this SP, we may highlight:
• The assessment done on the definition and performances of a modular test bench able to address unitary modules and combinations of modules. Limitations of such solution have been listed and corrective actions have been identified.
• The assessment performed on module evaluation, that has allowed a positive conclusion at process level (validation of test means and procedures), at module level (completion of Tests performed), and at interchangeability level (validation of expected goals in terms of mechanical and electrical interchangeability)

Nevertheless, additional testing activities should be performed in the near future (outside ACTUATION2015 project) in order to fulfil the complete range of expectations (mainly dynamic performances that have been insufficiently tested here).
• The validation of modularity interest in terms of cost, performance, integration, reliability targets on a qualitative aspect.

Quantitative numbers should be made available later by Airframers.
• The assessment/Impact of modularity on global Qualification cost, with a first evaluation of potential gain.

EADS-D: Modularity technology and cost assessments (WP63)
In the course of the ACTUATION2015 project, WP63 “Modularity technology and cost assessments” has assessed and validated the technical, economic and reliability related benefits in modularization and standardisation of the EMA. In particular, the results are:
- the concept has been developed and the models and metrics for technology and cost assessment of modular EMA in comparison to legacy actuation technologies have been adapted,
- the assessment methodology has been defined and the development of both the economic as well as the technical and reliability assessment concept development are described.
- academic and industrial state of the art has been derived: general assessment methods and metrics
that will be applied to WP63 are introduced. In accordance with all partners, case studies were defined to evaluate the advantages of standardised EMA compared to specific designed ones from a relative point of view.
- the economic impact of modular and standardised EMA for production, operation and maintenance (e.g. using Cost-Benefit-Analysis) have been assessed,
- the technical impact of modular and standardised EMA e.g. in terms of weight, complexity of system integration, maintainability, etc. has been assessed,
- the assessment results from technical, reliability and economic assessment have been compiled and the overall benefit of modular and standardised EMA has been provided. Finally, the WP has contributed to the SP6 objective of demonstrator validation by provision the assessment of cost, reliability and technical impacts of modular and standardised EMA in comparison to existing actuation solutions.

As a summary the actuators modularity and standardisation bring key benefits required for the electrical aircraft competitiveness in term of cost reduction with negligible impact on performance (weight, space envelop). The remaining challenge is now to optimise the level of integration for each individual module (e.g. ASIC for CMM, usage of hybrids for PCM) in order to achieve the space envelope and reliability objectives expected for series production. Beyond ACTUATION2015, most part of the developed modules will be tested by actuator manufacturers and airframers, all the way to flight test demonstration. The standards defined are evolving in order to be able to accommodate future electrical aircraft requirements as well as technology evolutions from 2025 onwards.

Potential Impact:
Major Benefits and Usable Results

- From Airframers perspective
The key benefits for the electrical aircraft can be sum up as follows:
- recurring costs
- non-recurring cost
- maintenance costs
- initial provisioning for the operators

The main contributor to the costs reduction is the actuation electronics standardisation. There are three main contributors for the Recurring Costs reduction at aircraft level:
1) High integration of aircraft control systems allowed by the actuators electronics standardisation:
- Shared resource regarding aircraft centralised avionics and local electronics
- Shared resource regarding Communications
- Optimized solutions regarding Power network

2) Higher production volume of the standardised modules.
- E.g. Same CMM for all applications (FCS, HLS, THS, BCS, NWS) and for all aircraft (Large, long range, short range, regional...)

3) Alignment of each system on a state-of-the-art architecture,
- some systems/actuators were far from an optimized solution, strong disparity was seen across aircraft applications.

The standardisation of the Power Drive Electronics has a big impact for the reduction of Non-Recurring Costs (NRC):
- Less equipment developments (e.g. one standard CMM development)
- Same standard modules used across new programs
- Scalable standard PDE modules addressing all aircraft actuation systems.

Generic modules cover a large functional scope with a wide flexibility (Application software download, Standardised Operation System) allowing applications beyond the FCS, HLS and LGS actuators.

- From Academics perspective
ACTUATION2015 gives the benefit to deliver important scientific results - actuator multi-physics modelling, - improving processes and tools for actuator architecting and sizing - methodology for virtual integration and testing. The project also permitted to get improved capabilities of academic partners to be prepared for the next projects leading to competitive European products as well as better understanding and faster response to airframer and supplier needs to reduce demanding iteration loops. Be prepared to support What-If Studies. Additionally, system thinking in a complex design task is important for the next generation of engineers (role of academic partners in teaching and post-university training). A final and important benefit would be the promotion of the European Scientific exchange network.
- From Actuators suppliers perspective
(Pre)-Standardisation allows tier 1 suppliers to have a much wider offer from all the companies of the whole supply chain (especially SMEs). Thanks to the common modular approach, tier 1 suppliers can, on the one side, address the current market more competitively, i.e. current products can be manufactured at lower costs and sold cheaper and on the other side, will be able to address a much bigger and wider market, i.e. can candidate for trans/multi-ATA instead of being focused on specific ATA.
- From SME perspective (EHP)
ACTUATION2015 project allows SMEs innovation and development of products fully dedicated to Aircraft and Actuators manufacturers (Visibility and dissemination; Open markets and collaboration opportunities).

European SMEs funding opportunities support providers diversity and excellence. It enhances competitiveness of critical knowledge and components (with respect to performances, mass, availability, costs, etc.)

ACTUATION2015 partners' collaborative skills are shared between partners:
- Aircraft and Actuator manufacturers open their skills and facilities to SMEs to adapt existing technologies to aircraft (i.e. from space or terrestrial fields).
- Follow-up during each ACTUATION2015 Review Meeting enables partners' exchanges and requirement set adaptations (to competitiveness).
- Access to such a large consortium gives a full overview of aircraft industry SOTA, Research and Development context and Work plans.
- Win-Win concurrent engineering work sessions.

Way forward: current and foreseen exploitation and developments

- From Airframers perspective
Beyond ACTUATION2015, most part of the developed modules will be tested by airframers all the way to flight test demonstration for TRL6 maturity.

The remaining challenge is now to optimise the level of integration for each individual module in order to achieve the space envelope and reliability objectives expected for series production.

The standards defined are evolving to be able to accommodate future electrical aircraft requirements as well as technology evolutions from 2025 onwards

- From Academics perspective

1) INSAT: PhD Student with SAGEM to extend the EMA Design Tools
2) INSAT: CS2 Project on EMA for Load Alleviation Function applied to RJ
3) TUHH: Further improvement of PreDEMA Tools in Cooperation with LIEBHERR
4) TUHH: BSA for next generation movables (Hybid FCS > high lift function with roll function)
5) TUHH: Distributed Flap Drive System-Demonstrator - Hardware Testrig (LuFo project)
6) TUHH – In-house Test Rig for Linear and Rotary EMA with HVDC for System Validation

- From Actuators suppliers perspective
In a short term perspective (less than one year): ACTUATION2015 results usable for EHA, as long as a few additional developments are made in terms of interfaces.

In a medium term perspective: ACTUATION2015 results usable for EMA on the so called “incremental” technologies updates on A/C (A320/A350, especially the EMA spoiler is a good candidate for the mid-term).

In a long term perspective: ACTUATION2015 results usable for EMA on the new aircraft (2028? Earlier? Later? Depending on Airframer roadmap).

- From SME perspective
ACTUATION2015 activities performed by Euro Heat Pipes already support several proposals concerning electronic cooling enhancement with two-phase heat spreader. Euro Heat Pipes aeronautics skills have been increased (helps to address more proposal with most adequate answer (i.e. Cleansky 2 – CfP), in terms of product, development and/or qualification needs, helps to derive space field experience to meet maintenance, LRU and recurrent costs of aeronautics).
The work performed during ACTUATION2015 has been collaboratively disseminated with Microsemi at Eurotherm102 conference, Limerick (Ireland), June 18th 2014. It has also been completed with National, European (Cleansky1) and internal funding to develop a wide two-phase heat spreader products line (different sizes, different cold source, different implementations ...). In a the future, the project outcomes will be part of the EHP International Conference communication at the 18th IHPC, Jeju, Korea, June 12-16, 2016: “The two-phase spreading of high heat fluxes density dissipative components for space and non-space applications” (to be released)

- Conclusion

FP7 European Level 2 project: a unique opportunity to gather all the stakeholders in one single project and to have them working together, sharing information ... Such a framework is not and cannot be available in the industrial “real” daily business.

European leading role in standardisation for EMA: ACTUATION2015 and the CEN work pave the way for new kinds of interactions between European companies and SAE (Society of Automotive Engineers). It allows pushing and promoting European leadership in setting up (not in following!) the further EMA standards. More specifically interaction between CEN/European industries and SAE A6-B3 has started. “A” stands for Aeronautics / “6” is for Flight control, actuators and hydraulic / “B3” is related to EMA; interest from leading European companies (airframers and major actuators suppliers) will lead at least in a medium term to the setting up and funding of dedicated strategic committee(s) and position papers.

ACTUATION2015 results directly used as basis and inputs for further development in several European collaborative initiatives, on-going and forthcoming, mainly Clean Sky 2 (especially with the SYS ITD, but also for some parts other ITDs: Regional aircraft, Airframe, Fast Rotor Craft ); H2020 level 1 forthcoming projects; FP9 preparation in addition with national and internal programmes (inside each company)
Regarding SP1 (Specifications for modular EMA)

The technical results achieved following the electrical actuators standardisation within ACTUATION2015 project have been assessed at aircraft level regarding recurring costs, non-recurring cost, maintenance costs, initial provisioning for the operators, weight and space envelopes.
The Power Drive Electronics standardisation results in a significant decrease of Recurring Costs (RC) at aircraft level. There are two main contributors for this RC reduction:
• High integration of aircraft control systems allowed by the actuator electronics standardisation (shared devices and solutions for aircraft-level/actuator-level electronics and communication and power network),
• Higher production volume of the standardised modules.
At actuator level, a modular product may be less optimised than a bespoke design but the overall aircraft benefit with standardised modules applied along the 50 actuators electronics is considerable.
Regarding the development effort the standardisation of the Power Drive Electronics has a big impact towards the reduction of Non-Recurring Costs (NRC): less equipment developments (e.g. one standard CMM product development instead of multiple), usage of the standard modules on new programmes, scalable standard PDE modules addressing all aircraft actuation systems. The generic modules are covering a large functional perimeter with a wide flexibility (downloaded software, standardised Operation System for multi-system implementation) allowing applications beyond the FCS, HLS and LGS actuators. Applications like eFan motors control and monitoring (electrical/hybrid engines) are in the scope of the generic modules (e.g. CMM), only the power level of the power core stage has to be sized.
Direct Maintenance Costs (DMC) and Initial Provisioning (IP) for airline operators will decrease significantly due to electronic modules standardisation. This benefit originates from lower repair costs and easier troubleshooting/maintenance operation. However, for this DMC reduction to be achieved, CMM and PCM modules must reach the correct integration level and reliability targets.
The weight saving associated to the better system integration as a consequence of standardised actuation electronics (wires amount, central electronics integration) offsets the slight weight increase of a modular actuator. There is always a risk of oversizing when using a standard module; however, the scope of functions covered by standard CMM and PCM is close to an optimum. The module weight penalty by covering both EHA and EMA actuators with a common CMM is negligible.
The space envelope of standardised modules depends upon the level of integration implemented by the equipment manufacturers. For some systems, the standardised PDE architecture and product already brings major weight benefits and space envelope reduction compared to actual designs on existing aircraft. For some other applications installed in small areas an effort on modules miniaturization has to be done. An advantage of the standardisation is to align each system on a state-of-the-art modular architecture and avoid the strong disparity seen today across aircraft applications. Standardisation of Power Drive Electronics has very little effect at aircraft level as regards to the weight.
The main challenge is now to achieve the required level of integration for each individual module (e.g. ASIC for CMM, usage of hybrids for PCM) in order to reach the space envelope and reliability targets expected for series production.

SP1 partners have applied a multidisciplinary integrated process (airframers, actuators manufacturers, components suppliers) to define the best modularity compromise for actuation electronics standardisation covering the aircraft control systems (flight controls, high lift, landing gears). The selected solutions are innovative and evolving. Standardised modules have been developed and integrated in flight control and landing gear demonstrators by the actuator manufacturers (SP2-5-6).
The actuators modularity and standardisation bring key benefits required for the electrical aircraft in terms of cost reduction with negligible impact on performance. The remaining challenge is now to optimise the level of integration for each individual module in order to achieve the space envelope and reliability objectives expected for series production.

Beyond ACTUATION2015, most part of the developed modules will be tested by actuator manufacturers and airframers, all the way to flight test demonstration. The standards defined are evolving in order to be able to accommodate future electrical aircraft requirements as well as technology evolutions from 2025 onwards.

Regarding SP3 (Methods and Tools)
During the second and third periods of the project it was possible to organise workshops to demonstrate the methods and tools developed in SP3. This gave rise to a wider use of such methods and tools by industrial partners, setting the basis for a long-term impact and continuity beyond ACTUATION2015. The most promising product of SP3 for future use is the Modelica Actuator Library. Its commercialisation is expected to take place during 2016 and a free copy will be made available for all project partners. The major benefits from the results achieved in SP3 can be summarized to:
• An improved capability of academic and research institutions to be prepared for the next projects leading to competitive European products,

• Better understanding and faster response to airframer and supplier needs to reduce demanding design iteration loops,
• System thinking in a complex design task – crucial for the next generation of engineers – will be transmitted to students through teaching and post-university training.

Apart from the on-going “industrial” exploitation of the results obtained, the methods and tools will be used in the short-term within national German and French projects. Thereby, the further utilization of such will also lead to further improvement. All scientific publications, finished and on-going Ph.D. theses related to the project, as well as dissemination workshops are listed in section 4.2.

List of Websites:
The project public website address is: www.actuation2015.eu
It has been created and launched in October 2012 and has been frequently kept up-to-date until the end of the project in April 2016 (and even beyond).

Project Coordinator
Mr. Marc-Olivier LEGRAND
GOODRICH ACTUATION SYSTEMS SAS (UTC Aerospace Systems Company)
106 Rue Fourny
78530 – Buc
FRANCE

E-mail: actuation2015@utas.utc.com