Final Report Summary - TAUPE (Transmissions in Aircraft on Unique Path wirEs)
Executive Summary:
The All Electric Aircraft is replacing conventional systems (hydraulic and pneumatic) with electric systems. But this development is currently facing a drastic issue: the increase of the number of wires (each electric system needs a power supply and communication networks) with negative impacts on systems weight and space allocation.
To save weight and space, the solution is to use a unique path wire to transmit power and data. But even though the related technologies are now mature, each technology has its own dedicated wires architecture and none is compliant with the aeronautical environment. Consequently, the aeronautic sector needs innovative solutions to merge the architectures into one full avionics-shared electrical and communication network. This is the purpose of the TAUPE project.
TAUPE is a collaborative research project supported by the Research Framework Programme 7 (FP7) of the European Commission with funds amounting to 6 Million Euros and involving 17 organisations from 6 European countries. Its goal is to reduce the length and mass of the aircraft cabling. To enable the All Electric Aircraft, TAUPE has defined a fully optimized avionic architecture for power and data transmission on unique path wires, mixing the aircraft power and communication networks.
TAUPE is targeting Technology Readiness Level (TRL) 4 (i.e. component and breadboard validation in laboratory environment) where the basic technological components are integrated in test benches to demonstrate that the components and the breadboard are working together.
To achieve this, TAUPE has introduced two technologies inside the aircraft: PLC (Power Line Communication) and PoD (Power over data). Both technologies essentially aim to supply power and data over the same cable, replacing two cables by a unique cable. The project partners have defined the requirements and the optimal architecture for PLC and PoD, to make it suitable both for existing aircraft (retrofit purposes) and for coming generations of composite aircraft.
An extensive modelling/simulation activity has been performed, and a simulation tool was produced and used to predict the feasibility and performances of the TAUPE Foreground. Based on this work and taking into account aeronautical standards, components were designed and adapted for two systems Mock-Ups: A CLS/CCS - Cabin Lighting and Communication system (to demonstrate PLC), and the A380 CDS-Cockpit Display System Mock-Up (to demonstrate PoD). Validation of the test-benches has been performed and the security aspects of the systems assessed. Both CLS/CCS and CDS were shown to be compliant with all safety requirements.
Several benefits can be expected from reduced cabling, mainly in the environmental area as reduced weight means reduced fuel consumption. However, benefits are also economic, since cable fitting, maintenance and retrofit can be simplified by reduced cabling. The outcome of TAUPE in terms of cable saving potential is a weight reduction of 359 kg and 36km less cable for an A380 aircraft. The potential fuel savings on a single A320 aircraft would amount to 36 000 $/year, a substantial economic and environmental benefit.
Project Context and Objectives:
TAUPE is a FP7 collaborative research project led by LABINAL/SAFRAN Engineering Services aiming at reducing the length and mass of the aircraft cabling by defining a fully-optimized avionic architecture on specific systems, mixing the aircraft power and communication networks. This implies introducing inside the aircraft:
- PLC technology (PowerLine Communication)
- PoD technology (Power over Data)
Both technologies essentially aim to supply power and data over the same cable:
Fully in line with ACARE Strategic Research Agenda, TAUPE has delivered specifications for harness wiring and network equipment/requirements for systems qualification.
These main results will allow system weight reduction, easy and cost-effective installation, retrofit and smart maintenance.
17 partners from 6 European countries (Figure 2) were involved in the TAUPE project and the project was organised into 8 Work Packages (WP): 5 Research Technology Development (RTD) WPs; 1 Dissemination WP; 1 Exploitation WP; and 1 Management WP.
Research Technology Development (RTD)
- WP1: Requirements and PLC/PoD optimised architecture (Leader: Airbus Operations)
? To identify electrical and communication networks for the next generation of carbon fuselage A/C and for existing A/C for retrofit purposes
? To define generic A/C architecture principles using PLC & PoD
? To validate the generic A/C architecture on a basis of a set of criteria using defined relevant applications (the reference applications)
? To specify the requirements for the reference applications used to validate the feasibility of the concept, to identify the critical demonstration elements and to define the V&V strategy
- WP2: Networks Definition and Simulation (Leader: LABINAL/Safran Engineering Services)
? To provide a channel model enabling applications classification for PLC & PoD.
? To provide a simulation tool to predict the feasibility and performance of PLC & PoD communications in terms of range, data rate and bit error rate.
? To provide physical architectures that are compliant with WP1 and that permit the Validation task to be carried out.
? To provide EMC and electronic constraints on equipment due to the modem integration.
- WP3:Mock-Up components design and adaptation (Leader: EADS-IW)
? To adapt the wiring networks of the benches to be used so that they will be compliant with WP4 integration and WP5 functional validation tests.
? To adapt current PLC solutions to EMC and transmission objectives taking into account aeronautical standards (RTCA DO160, DO178 and DO254 mainly) and to provide recommendations for future more adapted chipsets.
? To provide interfaces between reference A/C applications and the PLC modem targeting mock-up integration.
- WP4: Mock-Up Integration (Leader: HSLU)
? To provide components needed for PLC & PoD subsystem integration.
? To provide the bridges necessary to its implementation into the mock-up systems.
? To integrate the PLC modem subsystem and the interface adaptation modules developed in WP3 with equipment of the different reference applications.
- WP5: Verification and Validation tests (Leader: NLR)
? To provide the Verification & Validation (V&V) test plan to be used for the PLC & PoD equipments, taking into account certification, safety issues, the functionalities and capabilities of the reference applications in order to guarantee a reliable assessment.
? To ensure validation of all mock-up/test-bench applications (developed in WP4) in the associated test benches.
Dissemination
- WP6: Dissemination (Leader: Safran Engineering Services)
? To provide the TAUPE dissemination material (TAUPE public web site and documentation).
? To organise two public events (M18 and M42) to widely disseminate the results and insights available.
Exploitation
- WP7: Exploitation (Leader: Safran Engineering Services)
? To ensure the exploitation of the TAUPE results by collaboration with the JTI CLEAN SKY for incorporation of the TAUPE technologies in the JTI.
? To manage the TAUPE Intellectual Property Rights.
Management
- WP0: Project Management (Leader: Safran Engineering Services)
? To set up and maintain the management infrastructure (committees, boards, quality plan, procedures, risk registers, project management tools, internal collaborative web site, etc.)
? To provide technical coordination of the project partners
? To provide financial and contractual management of the consortium, especially regarding the European Commission expectancies
Targeted overall achievements are:
? Weight reduction
? Easy and cost-effective installation and possibly retrofit
? Cost-effective and smart maintenance
Project Results:
1.3 Description of the main S&T results/foreground
1.3.1 TAUPE Reference Applications
1.3.1.1 Cabin Lighting and Communication System (CLS/CCS)
The Cabin Lighting System (CLS) is designed to produce a level and harmony of lighting, which gives the passengers a sense of well being during various flight phases. The standard Cabin Lighting System consists of the many lighting elements, e.g. staircase lighting, spotlights with and without integrated emergency light, passenger LED reading lights in the passenger service units (PSUs) and avionics compartment lighting. For the TAUPE project, a simplified CLS have been taken into account.
The future CLS as defined by TAUPE is based on PLC technology. The TAUPE partners have decided to remove the Decoder-Encoder Units (DEUs) type A. Thus, this required functionality is integrated in the PLC Head-End Unit (PHEU).
The PHEU installed at one end of the line (CIDS side) acts as master in terms of synchronization and resource assignment. The PLC Terminal Units (PTUs) are associated to a PHEU at the other end of the line (equipment side) and act as slaves in terms of synchronization and resource assignment. Furthermore, two different PTU versions are available:
- PTU-28: A PTU for use with application equipment requiring a 28VDC power supply, i.e. the Passenger Service Unit (PSU) from the CCS.
- PTU-115: A PTU for use with application equipment requiring a 115VAC power supply, i.e. the Illumination Ballast Unit (IBU).
Furthermore, the future concept calls for the integration of these PLC devices directly into the application equipment
In order to provide increased safety, redundancy is provided through the use of two PLC modems within the PHEU, each with a different power supply interface.
PTUs are powered directly from the input power line (either 28VDC or 115VAC for the PTU-28 and PTU-115 respectively). Furthermore, the PTU-28 can be powered by the 28VDC emergency supply. In the case of loss of power to the normal distribution network, the PTUs will be supplied by the emergency power, however data is still modulated onto the normal distribution network since PLC operates normally even without an active power signal. The PTU-115 is not supplied from an emergency power supply and will therefore fail (PLC modem will not operate) if the 115VDC power supply fails.
The CLS/CCS demonstrator was built by the TAUPE partners according to these principles.
1.3.1.2 Cockpit Display System (CDS)
The Cockpit Display System is a system that provides a bi-directional communication link between pilots and aircraft. Through the display units, CDS displays main aircraft information to the flight crew. This information allows flight crew to have a good understanding of the environment (such as location, weather, terrain, traffic) and the current state of the aircraft (such as systems status, altitude). Pilots can also interact with some other systems via the CDS.
The CDS is composed of:
- Eight Display Units (DUs) using LCD technology, housed in the cockpit instrument panel,
- Two Keyboard and Cursor Control Units.
The internal communication between DU and KCCU is performed through a CAN bus. Two segregated CAN buses assure segregation between side 1 and 2. Only central displays have access to the KCCU Side 1 and Side 2.
The data flow between the avionics functions is performed via the Avionics Data Communication Network (ADCN). Each DU is connected to this network through AFDX switches.
The TAUPE partners have decided to focus their studies on Power-over-AFDX (PoAFDX) based solutions. Figure 7 shows a simple schematic diagram of a part of AFDX network focused on CDS. The individual PoAFDX switches have been marked as PoSW.
As previously mentioned, the future Cockpit Display System as defined by the TAUPE partners is based on PoAFDX technology. This technology is based on Power-over-Ethernet (PoE) but some modifications have been made.
It has to be kept in mind that all equipments will not be able to be powered by PoAFDX technology. Thus, the future network will use both classic AFDX (to link equipment powered by electrical power system) and PoAFDX (to link and to power equipment, including Display Units). Consequently, the 24 initial ports have been split into 16 AFDX ports and 8 PoAFDX ports.
For safety reasons, or more particularly for availability reasons, it has been decided to power each network (A and B) by separate electrical power supply sources. Equipments will switch automatically on back-up source in case of lost of initial one.
1.3.2 Technical background studies
1.3.2.1 Predicted performances of PLC in an aircraft Application to the CLS/CCS
Considering the complexity of the CLS system architecture, the variability of cabling inside aircraft and the difficulty to access aircraft or their test-benches, it was decided to work out a strategy based on numerical simulations of the channel. This strategy consists in:
- Modeling a simplified architecture of the CLS to sort out the most relevant parameters which characterize transmission features and to help design the Low Power Test Bench built by LABINAL/Safran Engineering Service.
- Modeling the test bench. This modeling is validated by comparison between simulation and measurements. Numerical simulations fill a data base containing channel features. Future possible optimizations of this channel are proposed
The whole set of numerical simulations was carried out with the CRIPTE software, developed by ONERA and widely validated in previous research projects. This code is based on a topological representation of electromagnetic interference on harnesses by applying the multi-conductor transmission line theory in the frequency domain. The specificity of this work, here, is the management of the CLS network complexity of its architecture itself, as bundles density and their random cross section geometry, and dimensions of the whole network compared to the frequency bandwidth under study (1MHz 50MHz).
Characteristics of the propagation channel are evaluated in the frequency domain between 100 kHz and 50 MHz in terms of S-parameters of the 2-port network in which port 1 is the extremity of the link connected to SPDB and port 2 is the extremity of the link connected to an elementary IBU. The definition of the S-parameter matrix is recalled in Figure 9. Note that two configurations of emission/reception have been introduced:
- Common mode driving: Emission/reception between a single wire and the reference ground plane,
- Differential mode driving: Emission/reception between 2 wires (twisted pair).
In both configurations, all conductors in the harness contribute to the propagation from one point to another point of the whole link.
A preliminary statistical analysis has shown that, for the CM as for the DM configurations, the channel characteristics are not strongly dependent on h, the average height of the harness over the reference plane, chosen equal to 2.8 cm. Furthermore, since the channel transfer function is likely strongly influenced by the coupling to the other wires in the same bundle, a parametric study has been carried out by randomly chosen the loads on these wires. Four cases are considered in Figure 10 which gives the transfer function between the SPDB and an IBU situated at a distance of 24 m. Either all neighbour wires are terminated on a short circuit (term. 1), on an open circuit (term. 4) or on 50 ? (Term 3). For the final case, half neighbouring wires are loaded with 50 ?, the second half is short-circuited (Term 2).
In Figure 10, we see that when the whole network becomes resonant, terminal loads on all wires modify the S21 parameter. This effect is weaker in DM driving, since in this case, cross coupling with neighbouring wires inside the harness is reduced.
One important feature of the DM excitation is the decrease of the common current Icm propagating along the cable bundle during a PLC transmission. Indeed, this current must not exceed the maximum level of 20 dB?A in a 1 kHz bandwidth, as specified by the DO-160 standards for this type of transmission on the cable network and for its environment. The CM rejection strongly depends on the physical structure of the PLC twisted line and on the symmetry of the input/output transformers. Experiments have shown that a rejection of 20 dB can practically be achieved in the whole PLC frequency band.
These theoretical results have been validated owing to measurement made on the test bench and also compared to measurements on the A340/A600 and on the CLS-CCS demonstrator. EMC aspects as radiation of the PLC link and crosstalk in the CLS harness have been also analyzed.
A software tool allowing the simulation of a PLC transmission, using Orthogonal Frequency Division Multiplexing (OFDM) in a 1-30 MHz band has been developed and an extensive parametric study has been carried out to analyze the performance of the PLC link.
Initially, the selected technology for PLC communication was based on the standard OPERA specifications. Since then, multiple international and industrial standards for PLC have been developed, such as HomePlug AV (HPAV).
Consequently, a first simulation tool was developed, partly in C language and partly under Matlab, to predict the performance of the link under OPERA. A perfect synchronization between transmitting and receiving modems was assumed. The main characteristics of the OPERA standard are a Reed Solomon encoder, a 4D TCM (Four Dimensional Trellis Coded Modulation) and mapping using ADPSK modulation. Among the 2048 sub carriers, equally spaced in a bandwidth either equal to 10, 20 or 30 MHz, only 1536 carriers are used for the transmission. The results of the simulation were obtained by assuming a bandwidth of 30 MHz, called type 1 in OPERA specifications. The complex transfer function deduced either from the theoretical model or from measurements was introduced in the model. Noise was assumed to be an additional white Gaussian noise having a current spectral density of 10 dBµA/kHz. This value has been chosen since the CM disturbing current on the other wires must not exceed 20 dBµA/kHz (DO-160 standards) and the coupling loss between these other wires and the PLC line has been estimated to about 10 dB.
A second simulation tool, based on HPAV has been designed to predict the maximum bit rate to guarantee a Bit error Rate (BER) smaller than a given value. In our simulations, a BER<= 10-3 is chosen for limiting the computation time. In Figure 10, the throughput is plotted versus the common mode current spectral density, assuming a DM excitation. The red curves refer to the 14 modelled channels between SPDB and the IBUs and the blue curves refer to the 16 measured channels in the CLS/CCS demonstrator between PHEU and PTU. For a maximum value of the resulting common mode current of 20 dBµA/kHz (DO160), and considering a maximum BER of 10-3, the throughput of the link varies between 12 and 62 Mbits/s.
Finally, experiments of data transmission have been carried out on the low power test bench with versatile modems (based on FPGAs and following HPAV standards), designed and realized by USTL. The experiments have shown that throughputs greater than 30 Mbits/s are achieved, disturbing noise on the adjacent wires and CM noise due to PLC communication fulfilling the DO-160 standards.
1.3.3 Verification and Validation results
1.3.3.1 Requirements verification
General, Safety and EMC requirements for both TAUPE technologies (PLC and PoD) have been formulated and verified during the project. Not all requirements are applicable or verified for this project. However they may be applicable for a future TAUPE project at a higher TRL level.
The following verification methods were used to determine the compliance with the requirements: Unit Test, System Test, Analysis and Review-of-Design.
Non-compliances were only found in the following areas:
- Some network performance deficiencies as result of the used PLC technology in aeronautical domain;
- Radiated emissions;
- Power supply design;
- Equipment level safety aspects, mainly for PLC.
All these non-compliances have been carefully analysed and studied to propose system improvement. Way forwards have been proposed to successfully comply with identified non compliance.
Currently, the non compliance are considered non critical and are no showstopper for further development.
Regarding the process evaluation, it can be concluded that the process as planned and applied was suitable to verify the TAUPE requirements and to validate the TAUPE system.
The safety approach proposed during the TAUPE project is based on a standard V process. Activities are first performed at system level (CDS and CLS), and then at equipment level (PLC, PoD modems). It is important to note that the proposed process is consistent with the applicable standards of aeronautic systems.
The performed safety analyses describe the capability of TAUPE solutions to respect the aeronautical safety requirements. It has been shown that for safety point of view, the TAUPE PLC and PoD modems are in line with the constraints of the aeronautical domain. No blocking points have been identified regarding the safety level required at equipment level neither for PLC and PoD modems nor, at system level, CLS and CDS systems.
1.3.3.2 Technical maturity reached during the project
The Technology Readiness Level (TRL) scale is a measure to assess the maturity of evolving technology. It was originally developed by the National Aeronautics and Space Administration (NASA). The TRL definition, as it is currently used, consists of nine levels that represent technology growth from the start (basic principles observed) to fully operational use.
The TRL scale used in TAUPE is shown in Table 1, with the TAUPE TRL objective of 4 in bold italics. TRL4 is described as "Basic technological components are integrated to establish that the pieces will work together. This is "low fidelity" compared to the eventual system. Examples include integration of 'ad hoc' hardware in a laboratory."
Moreover, the DoD Technology Readiness Assessment Guidance document provides some additional supporting information for the intended TRL 4: "System concepts that have been considered and results from testing laboratory-scale breadboard(s). References to who did this work and when. Provide an estimate of how breadboard hardware and test results differ from the expected system goals."
Table 1. TRL scale used in TAUPE
TRL
1 Basic principles observed and reported
2 Technology concept and/or application formulated
3 Analytical and experimental critical function and/or characteristic proof of concept
4 Component and/or breadboard validation in laboratory environment
5 Component and/or breadboard validation in relevant environment
6 System/subsystem model or prototype demonstration in a relevant environment
7 System/subsystem model or prototype demonstration in a relevant environment
8 Actual system completed and 'flight qualified' through test and demonstration
9 Actual system 'flight proven' through successful mission operations
The level of maturity can basically be determined by looking at the TRL definitions and deciding which of these best matches the achieved level of the technology. This is a simple and straightforward method. For TAUPE project it is clear that the intended goal of TRL 4 has been reached. However, the determination of the TRL from such a table is not necessarily objective. A tool used to more accurately determine the TRL of technology development is the TRL Calculator from the US Air Force Research Laboratory (AFRL). Using this tool as well, it can be concluded that the maturity level of TRL 4 has been reached, since all hardware TRL 4 questions and even a number of TRL 5 questions could be answered positively.
1.3.3.3 Impact on weight and fuel saving
To estimate the weight of components that can be removed by using PLC technology in an A380, it is considered that CAN, ARINC429 and other communication buses were routed through twin shielded wires. Then, it is considered that twisted shielded databuses were entirely replaced by PLC technology and that mass of the PLC components, PTU (around 20g) and PHEU (between 70 and 90g) were equivalent to existing interface electronic card mass. With those assumptions, the maximum saving potential on A380 is 360 kg.
To generalize the result of using PoAFDX at aircraft level it was decided to compute the weights prorate for the CDS, and to apply it to the systems potentially using the PoAFDX technology. A total of 50 pieces of equipment are eligible to PoAFDX use. The weight of the power cables that could be removed in the eligible systems represents 65 kg on an A380 aircraft. However, the PoAFDX switch size is increased since it embeds new functionality, adding 400 grams more weight to each switch. Also, the converter, filter and injector are evaluated to be 600 grams. Since 16 switches are installed onboard A380, 16 kg shall be added in total. It can be concluded that on an Airbus A380 a weight of 49 kg could be saved if PoAFDX technology is deployed.
The relation between weight and fuel savings on the A320 can be found in document Getting to grips with the A320 Family performance retention and fuel savings, which is publicly available on the internet. Based on the information contained in this document, the weight reductions obtained by using PoAFDX results in minimum 2750$ and maximum 5000$ of annual savings for an A320 flying on a typical sector. The weight savings obtained by using PLC would result in 36 000$ a year for the same aircraft.
1.3.3.4 Benefits in terms of simplification of cabling system, installation, maintenance and retrofit
In case of PLC, the data cables are removed. The power line, currently monofilar (single wire), is either kept as it is, or is replaced by a bifilar version (twin wire). It was shown in the TAUPE project that transmitting data on a monofilar wire do not allow high transmission rates. In addition, the study showed that a bifilar approach without shielding could be used, contrary to common data cables (like those for ARINC 429 or CAN). This can be considered as one connection less, since the braiding does not need to be connected to the connector mass. It simplifies the harness manufacture when the connector is installed during the manufacturing, or decrease the time in assembly line to connect the harness to rear equipment connector.
If it is assumed that the bifilar approach is generalized and the data cables are already a shielded bifilar, then the introduction of PLC replaces one wire (power) + one shielded twisted pair by one twisted pair only. In the case of the CLS, this means 565 links less with PLC than before.
In case of PoD, PoAFDX introduction would lead to power cable removal of 228 meters of cable, which represent 60% gain for CDS specific application.
Heavy maintenance of wiring harnesses is not needed during aircraft life, and harness replacement is very rare once the aircraft definition becomes mature. Therefore, the estimated maintenance simplification potential due to the use of TAUPE technologies is qualitative and cannot be computed. Calculations are equally impossible for retrofit benefits as well. When retrofitting an aircraft, the main cost is due to the time needed to design, manufacture and install the harness. The cable simplification seen above is low compared to this main cost but it certainly would bring benefit for retrofit.
1.3.4 Conclusion
TAUPE has introduced verified and validated PLC (Power Line Communication) and PoD (Power over data) technology inside the aircraft, to supply power and data over the same cable, replacing two cables with a unique one. The project partners have defined the requirements and the optimal architecture of the PLC and PoD systems, to make it suitable both for existing aircraft (for retrofit purposes) and for coming generations of composite aircraft.
An extensive modelling/simulation activity has been performed, and a simulation tool was produced and used to predict the feasibility and performances the technologies. Based on this work and taking into account aeronautical standards, components were designed and adapted for two systems Mock-Ups: A Cabin Lighting and Communication system, verifying and validating PLC technology, and an A380 Cockpit Display System Mock-Up, verifying and validating PoD technology. Validation of the test-benches has been performed and the security aspects of the systems assessed. Both CLS and CDS were shown to be compliant with all safety requirements and confirming the result maturity at TRL 4.
Thanks to TAUPE results (the outcome of TAUPE in terms of cable saving potential is a weight reduction of 359 kg and 36km less cable for an A380 aircraft, whereas the potential fuel savings on a single A320 aircraft would amount to 36 000 $/year), several benefits can now be expected, mainly in the environmental area as reduced weight means reduced fuel consumption. However, benefits are also economic, since cable fitting, maintenance and retrofit can be simplified and cost effective by reduced cabling.
Potential Impact:
1.4 Potential impact
The TAUPE results are paving the way to innovative full avionic architecture mixing aircraft electrical and communication networks. The resulting association with related specifications (harness wiring, network equipment), related requirements (system qualification) and the related technologies will allow easy, rapid and secure integration of on-board electrical systems.
The technologies used by the project are PLC & PoD, integrated in equipments and components compliant with aircraft constraints and safety requirements. Beyond enabling the All Electric aircraft and the integration of on-board electrical systems, TAUPE results will also enable the reduction of operating cost through reduction in fuel consumption (approx 180 tonnes of fuel saved for the A320 fleet) and other following direct operating cost. It will then be possible for airlines companies to reduce travel charges accordingly.
This project has been conducted in line with ACARE Strategic Research Agenda 2 (High Level Target Concept The Highly Cost Efficient Air Transport System) and in particular in line with the activities envisaged in the frame of the System for green operations of JTI CLEAN SKY and with Vision 2020 goals. TAUPE has participated to enable the Cost effective aircraft by providing innovative responses to aircraft challenges, such as solutions to reduce wiring on board, in order to save weight & cost. This research will allow reduction of a large number of connections and tests in the final assembly line of future aircraft, the simplification of system design architectures and maintenance. This has positive impact on security, cost and time issues.
TAUPE has provided benefits to citizens, society and climate, considering the potential weight reduction of future aircraft. The results show a measurable potential reduction of fuel consumption, as well as CO2 and NOx emissions. The cost effective retrofit capacity will allow current airlines fleets to become greener aircraft and this has an impact on aircraft life cycle.
The project has supported competitiveness of European industries in the global market by guaranteeing safety (design robustness able to meet certification requirements), industrialisation and the related costs and portability to other equipment. A contribution to the production of electric and telecommunication standards has also been made.
By widely disseminating its results through public forum and strong relationships with FP6 and FP7 project and CLEAN SKY, TAUPE has also participated to strengthen the competitiveness of the European supply chain.
1.5 Dissemination activities
TAUPE partners have been committed to widely disseminating the technical assessment of the project to suppliers, SMEs, Academics and Research centres.
Dissemination activities in TAUPE were focused on 3 main objectives:
- Ensure the TAUPE resulting technology will be brought to higher TRL level (6-7) as part of the project exploitation
- Strengthen the competitiveness of European Aero-systems Industry and its supply chain for integration of new technology in products
- Strengthen academics and Research centres awareness, knowledge and efforts to support the aero-systems sector in future programme
These objectives were achieved through the following dissemination actions:
- Exchanges with stakeholders for standardisation purposes and dissemination of results and knowledge
- Public events (M18 and M42)
- Dissemination materials
- Scientific and Technical publications
- Public website with contact details
1.5.1 Exchanges with stakeholders for standardisation purposes and disseminate TAUPE results and complement knowledge
For the time being, the work within the well-known established standardisation organisations, for example EUROCAE, IEEE or ARINC, is primarily focussing on interworking, interoperability, co-existence aspects rather than on common harmonised standards. TAUPE, a project at TRL4, has therefore focused its effort on demonstrating the certificability of its results developed from existing standards (e.g. OPERA).
In preparation of a follow-up project maturing current results to a higher TRL level, frequent communication of the TAUPE results in the presence of standardisation stakeholders have been undertaken in order to raise awareness of recent progress in the field.
1.5.2 TAUPE Dissemination Events
TAUPE has organised 2 dedicated public dissemination events (M18 and M42) to present the main project results and technology benefits to the aeronautics industry, academia and research centres, and gathering 150 attendees from Europe and North America.
1.5.2.1 M18 Dissemination event
This first dissemination event was organised in conjunction with the Avionics Europe 2010 conference and exhibition, in order to attract attendees as much as possible.
It took place in Amsterdam, March 25, 2010 and presented (Figure 13) the M18 results of the TAUPE project with:
- PLC investigation on Low Power Test Bench, representative of the reference applications installed in the aircraft
- Techniques to reduce common mode current & radiated emissions
- Numerical assessment of channel properties for future application and use of PLC in Aircraft
- Feasibility and performances of a PLC Communication
- Bifilar approach
- Feasibility of PLC in the context of aircraft cabin
- Safety Approach
- Verification and Validation aspects
The overall achievements of this event were:
- TAUPE results have raised awareness of stakeholders (Aeronautics, surface transport and Space) and made them aware of TAUPE partners competencies
- Exploitation of results and/or continuation of the project concepts beyond TRL 4 are strengthened with several contacts initiated for further discussions
1.5.2.2 M42 Final dissemination event
The final dissemination event, held in Paris, 15 February, 2012, presented the results of the TAUPE project with:
- PLC RTD developments on Cabin Mock-Up, including the cabin light system and communication system, demonstrated on site (Figure 14)
- PoD RTD developments of Cock-pit Display System on A380 Test-bench
- TRL reached by the project and the results qualification towards Certification and Safety
- Assessment of results against Cost effective Aircraft with calculated savings on weight and fuel as well as positive perspectives for maintenance and assembly
This event was very successful with the presence of the EC, the press, and fruitful questions/answers sessions raising opportunities for exploitation and future project to maturate the TAUPE.
The overall achievements of this event were:
- TAUPE results have raised awareness of stakeholders and made them aware of TAUPE partners competencies
- Technical feasibility, reliability and safety of PoD and PLC have been demonstrated
- Exploitation of results and/or continuation of the project concepts beyond TRL 4 are strengthened with several contacts initiated for further discussions
1.5.3 Project presentation material
In order to convey a professional and consistent image of the project, basic presentation material to support information dissemination actions, such as a project logo, letterhead and presentations template, was provided at the beginning of the project. Posters, Pop-up banners and flyers and information leaflets were produced and distributed, both at TAUPE events and major aeronautics events where TAUPE partners participated, such as the ESA Workshop on Aerospace and Singapore Air show. This material has delivered messages targeting the expected attendees to such workshops: environmental concerns, cost saving and innovation.
1.5.4 Scientific publications and presentations in key journals and aeronautic conferences.
The academic partners involved in TAUPE have published frequently in peer-reviewed journals with international scope, such as IEEE transactions and magazine on aerospace and electronics system, IEEE transactions on EMC, IEEE transactions on power delivery and IEEE transactions on communication.
Both academic and industrial TAUPE partners have also actively participated in conferences and workshops relevant for TAUPE purposes. These network activities have been important to avoid duplication of research activities and to raise awareness about PoD and PLC technologies evolution.
1.6 Public website and contact details
The public website on the TAUPE project is accessible at: http://www.TAUPE-Project.eu
The Taupe public website has been visited 6.791 times by 4.449 unique visitors. As an average, each visitor is viewing 3,85 pages per visit, the most popular page is the page where publications and presentation can be downloaded.
Most visitors connected from:
1/ France,
2/ Germany
3/ USA
The analysis of the domains connected showed that industrials (airframers and systems providers) are regular visitors. Mainly used to widely disseminate project results as well as the proceedings from the public dissemination events (M18 and M42), the Taupe public website also contains a presentation of the TAUPE project, key figures, the presentation of the project partners with contact details.
List of Websites:
Public website: http://www.TAUPE-Project.eu
The TAUPE coordinator is:
François Gogé,
Technical Director
SAFRAN ENGINEERING SERVICES
The TAUPE partners are:
AIRBUS OPERATIONS SAS
316 route de Bayonne
31060 Toulouse cedex 09
France
ARTTIC
58a, rue du Dessous des Berges
F-75013 Paris
FRANCE
DIEHL AEROSPACE
Donaustrasse 120
D-90451 Nürnberg
Germany
EADS Deutschland GmbH
Sensors, Electronics & Systems Integration
Dept.TCC4/ IW-SI EC
81663 Munich
Germany
Ecole Polytechnique Fédérale de Lausanne (EPFL)
Swiss Federal Institute of Technology - EMC Group
EPFL-STI-LRE, ELL-138, Station 11
1015 Lausanne
Switzerland
EKIS
31st Dionisie Lupu street, 2nd floor, 3rd apartment, 2nd District
020021 Bucharest
ROMANIA
Haute Ecole dIngénierie et de Gestion du Canton de Vaud (HEIG)
Institute for Information and Communication Technologies
Route de Cheseaux 1
1400 Yverdon-les-bains
Switzerland
HISPANO SUIZA
18, Boulevard Louis Seguin
92707 Colombes Cedex
France
Hochschule Luzern Technik & Architektur (HSLU)
Technikumstr. 21
6048 Horw
Switzerland
HORTEC BV
Zutphenstraat 53
7575 EJ Oldenzaal
Netherlands
ONERA
DCV/SGA
2 avenue Edouard Belin, BP 4025
31055 Toulouse Cedex 4
France
LABINAL/SAFRAN Engineering Services
Victoria Centre 2
20 Chemin de Laporte
31300 Toulouse
France
Stichting Nationaal Lucht- en Ruimtevaartlaboratorium (NLR)
Voorsterweg 31
8316PR Marknesse
Netherlands
Thales Avionics
105, av. du Général Eisenhower
BP 63647
31036 Toulouse cedex 1
France
Université des Sciences et Technologies de Lille (USTL)
U.S.T.L. Lille 1 - IEMN/UMR 8520
Bâtiment P3
59655 Villeneuve d'Ascq
France
The All Electric Aircraft is replacing conventional systems (hydraulic and pneumatic) with electric systems. But this development is currently facing a drastic issue: the increase of the number of wires (each electric system needs a power supply and communication networks) with negative impacts on systems weight and space allocation.
To save weight and space, the solution is to use a unique path wire to transmit power and data. But even though the related technologies are now mature, each technology has its own dedicated wires architecture and none is compliant with the aeronautical environment. Consequently, the aeronautic sector needs innovative solutions to merge the architectures into one full avionics-shared electrical and communication network. This is the purpose of the TAUPE project.
TAUPE is a collaborative research project supported by the Research Framework Programme 7 (FP7) of the European Commission with funds amounting to 6 Million Euros and involving 17 organisations from 6 European countries. Its goal is to reduce the length and mass of the aircraft cabling. To enable the All Electric Aircraft, TAUPE has defined a fully optimized avionic architecture for power and data transmission on unique path wires, mixing the aircraft power and communication networks.
TAUPE is targeting Technology Readiness Level (TRL) 4 (i.e. component and breadboard validation in laboratory environment) where the basic technological components are integrated in test benches to demonstrate that the components and the breadboard are working together.
To achieve this, TAUPE has introduced two technologies inside the aircraft: PLC (Power Line Communication) and PoD (Power over data). Both technologies essentially aim to supply power and data over the same cable, replacing two cables by a unique cable. The project partners have defined the requirements and the optimal architecture for PLC and PoD, to make it suitable both for existing aircraft (retrofit purposes) and for coming generations of composite aircraft.
An extensive modelling/simulation activity has been performed, and a simulation tool was produced and used to predict the feasibility and performances of the TAUPE Foreground. Based on this work and taking into account aeronautical standards, components were designed and adapted for two systems Mock-Ups: A CLS/CCS - Cabin Lighting and Communication system (to demonstrate PLC), and the A380 CDS-Cockpit Display System Mock-Up (to demonstrate PoD). Validation of the test-benches has been performed and the security aspects of the systems assessed. Both CLS/CCS and CDS were shown to be compliant with all safety requirements.
Several benefits can be expected from reduced cabling, mainly in the environmental area as reduced weight means reduced fuel consumption. However, benefits are also economic, since cable fitting, maintenance and retrofit can be simplified by reduced cabling. The outcome of TAUPE in terms of cable saving potential is a weight reduction of 359 kg and 36km less cable for an A380 aircraft. The potential fuel savings on a single A320 aircraft would amount to 36 000 $/year, a substantial economic and environmental benefit.
Project Context and Objectives:
TAUPE is a FP7 collaborative research project led by LABINAL/SAFRAN Engineering Services aiming at reducing the length and mass of the aircraft cabling by defining a fully-optimized avionic architecture on specific systems, mixing the aircraft power and communication networks. This implies introducing inside the aircraft:
- PLC technology (PowerLine Communication)
- PoD technology (Power over Data)
Both technologies essentially aim to supply power and data over the same cable:
Fully in line with ACARE Strategic Research Agenda, TAUPE has delivered specifications for harness wiring and network equipment/requirements for systems qualification.
These main results will allow system weight reduction, easy and cost-effective installation, retrofit and smart maintenance.
17 partners from 6 European countries (Figure 2) were involved in the TAUPE project and the project was organised into 8 Work Packages (WP): 5 Research Technology Development (RTD) WPs; 1 Dissemination WP; 1 Exploitation WP; and 1 Management WP.
Research Technology Development (RTD)
- WP1: Requirements and PLC/PoD optimised architecture (Leader: Airbus Operations)
? To identify electrical and communication networks for the next generation of carbon fuselage A/C and for existing A/C for retrofit purposes
? To define generic A/C architecture principles using PLC & PoD
? To validate the generic A/C architecture on a basis of a set of criteria using defined relevant applications (the reference applications)
? To specify the requirements for the reference applications used to validate the feasibility of the concept, to identify the critical demonstration elements and to define the V&V strategy
- WP2: Networks Definition and Simulation (Leader: LABINAL/Safran Engineering Services)
? To provide a channel model enabling applications classification for PLC & PoD.
? To provide a simulation tool to predict the feasibility and performance of PLC & PoD communications in terms of range, data rate and bit error rate.
? To provide physical architectures that are compliant with WP1 and that permit the Validation task to be carried out.
? To provide EMC and electronic constraints on equipment due to the modem integration.
- WP3:Mock-Up components design and adaptation (Leader: EADS-IW)
? To adapt the wiring networks of the benches to be used so that they will be compliant with WP4 integration and WP5 functional validation tests.
? To adapt current PLC solutions to EMC and transmission objectives taking into account aeronautical standards (RTCA DO160, DO178 and DO254 mainly) and to provide recommendations for future more adapted chipsets.
? To provide interfaces between reference A/C applications and the PLC modem targeting mock-up integration.
- WP4: Mock-Up Integration (Leader: HSLU)
? To provide components needed for PLC & PoD subsystem integration.
? To provide the bridges necessary to its implementation into the mock-up systems.
? To integrate the PLC modem subsystem and the interface adaptation modules developed in WP3 with equipment of the different reference applications.
- WP5: Verification and Validation tests (Leader: NLR)
? To provide the Verification & Validation (V&V) test plan to be used for the PLC & PoD equipments, taking into account certification, safety issues, the functionalities and capabilities of the reference applications in order to guarantee a reliable assessment.
? To ensure validation of all mock-up/test-bench applications (developed in WP4) in the associated test benches.
Dissemination
- WP6: Dissemination (Leader: Safran Engineering Services)
? To provide the TAUPE dissemination material (TAUPE public web site and documentation).
? To organise two public events (M18 and M42) to widely disseminate the results and insights available.
Exploitation
- WP7: Exploitation (Leader: Safran Engineering Services)
? To ensure the exploitation of the TAUPE results by collaboration with the JTI CLEAN SKY for incorporation of the TAUPE technologies in the JTI.
? To manage the TAUPE Intellectual Property Rights.
Management
- WP0: Project Management (Leader: Safran Engineering Services)
? To set up and maintain the management infrastructure (committees, boards, quality plan, procedures, risk registers, project management tools, internal collaborative web site, etc.)
? To provide technical coordination of the project partners
? To provide financial and contractual management of the consortium, especially regarding the European Commission expectancies
Targeted overall achievements are:
? Weight reduction
? Easy and cost-effective installation and possibly retrofit
? Cost-effective and smart maintenance
Project Results:
1.3 Description of the main S&T results/foreground
1.3.1 TAUPE Reference Applications
1.3.1.1 Cabin Lighting and Communication System (CLS/CCS)
The Cabin Lighting System (CLS) is designed to produce a level and harmony of lighting, which gives the passengers a sense of well being during various flight phases. The standard Cabin Lighting System consists of the many lighting elements, e.g. staircase lighting, spotlights with and without integrated emergency light, passenger LED reading lights in the passenger service units (PSUs) and avionics compartment lighting. For the TAUPE project, a simplified CLS have been taken into account.
The future CLS as defined by TAUPE is based on PLC technology. The TAUPE partners have decided to remove the Decoder-Encoder Units (DEUs) type A. Thus, this required functionality is integrated in the PLC Head-End Unit (PHEU).
The PHEU installed at one end of the line (CIDS side) acts as master in terms of synchronization and resource assignment. The PLC Terminal Units (PTUs) are associated to a PHEU at the other end of the line (equipment side) and act as slaves in terms of synchronization and resource assignment. Furthermore, two different PTU versions are available:
- PTU-28: A PTU for use with application equipment requiring a 28VDC power supply, i.e. the Passenger Service Unit (PSU) from the CCS.
- PTU-115: A PTU for use with application equipment requiring a 115VAC power supply, i.e. the Illumination Ballast Unit (IBU).
Furthermore, the future concept calls for the integration of these PLC devices directly into the application equipment
In order to provide increased safety, redundancy is provided through the use of two PLC modems within the PHEU, each with a different power supply interface.
PTUs are powered directly from the input power line (either 28VDC or 115VAC for the PTU-28 and PTU-115 respectively). Furthermore, the PTU-28 can be powered by the 28VDC emergency supply. In the case of loss of power to the normal distribution network, the PTUs will be supplied by the emergency power, however data is still modulated onto the normal distribution network since PLC operates normally even without an active power signal. The PTU-115 is not supplied from an emergency power supply and will therefore fail (PLC modem will not operate) if the 115VDC power supply fails.
The CLS/CCS demonstrator was built by the TAUPE partners according to these principles.
1.3.1.2 Cockpit Display System (CDS)
The Cockpit Display System is a system that provides a bi-directional communication link between pilots and aircraft. Through the display units, CDS displays main aircraft information to the flight crew. This information allows flight crew to have a good understanding of the environment (such as location, weather, terrain, traffic) and the current state of the aircraft (such as systems status, altitude). Pilots can also interact with some other systems via the CDS.
The CDS is composed of:
- Eight Display Units (DUs) using LCD technology, housed in the cockpit instrument panel,
- Two Keyboard and Cursor Control Units.
The internal communication between DU and KCCU is performed through a CAN bus. Two segregated CAN buses assure segregation between side 1 and 2. Only central displays have access to the KCCU Side 1 and Side 2.
The data flow between the avionics functions is performed via the Avionics Data Communication Network (ADCN). Each DU is connected to this network through AFDX switches.
The TAUPE partners have decided to focus their studies on Power-over-AFDX (PoAFDX) based solutions. Figure 7 shows a simple schematic diagram of a part of AFDX network focused on CDS. The individual PoAFDX switches have been marked as PoSW.
As previously mentioned, the future Cockpit Display System as defined by the TAUPE partners is based on PoAFDX technology. This technology is based on Power-over-Ethernet (PoE) but some modifications have been made.
It has to be kept in mind that all equipments will not be able to be powered by PoAFDX technology. Thus, the future network will use both classic AFDX (to link equipment powered by electrical power system) and PoAFDX (to link and to power equipment, including Display Units). Consequently, the 24 initial ports have been split into 16 AFDX ports and 8 PoAFDX ports.
For safety reasons, or more particularly for availability reasons, it has been decided to power each network (A and B) by separate electrical power supply sources. Equipments will switch automatically on back-up source in case of lost of initial one.
1.3.2 Technical background studies
1.3.2.1 Predicted performances of PLC in an aircraft Application to the CLS/CCS
Considering the complexity of the CLS system architecture, the variability of cabling inside aircraft and the difficulty to access aircraft or their test-benches, it was decided to work out a strategy based on numerical simulations of the channel. This strategy consists in:
- Modeling a simplified architecture of the CLS to sort out the most relevant parameters which characterize transmission features and to help design the Low Power Test Bench built by LABINAL/Safran Engineering Service.
- Modeling the test bench. This modeling is validated by comparison between simulation and measurements. Numerical simulations fill a data base containing channel features. Future possible optimizations of this channel are proposed
The whole set of numerical simulations was carried out with the CRIPTE software, developed by ONERA and widely validated in previous research projects. This code is based on a topological representation of electromagnetic interference on harnesses by applying the multi-conductor transmission line theory in the frequency domain. The specificity of this work, here, is the management of the CLS network complexity of its architecture itself, as bundles density and their random cross section geometry, and dimensions of the whole network compared to the frequency bandwidth under study (1MHz 50MHz).
Characteristics of the propagation channel are evaluated in the frequency domain between 100 kHz and 50 MHz in terms of S-parameters of the 2-port network in which port 1 is the extremity of the link connected to SPDB and port 2 is the extremity of the link connected to an elementary IBU. The definition of the S-parameter matrix is recalled in Figure 9. Note that two configurations of emission/reception have been introduced:
- Common mode driving: Emission/reception between a single wire and the reference ground plane,
- Differential mode driving: Emission/reception between 2 wires (twisted pair).
In both configurations, all conductors in the harness contribute to the propagation from one point to another point of the whole link.
A preliminary statistical analysis has shown that, for the CM as for the DM configurations, the channel characteristics are not strongly dependent on h, the average height of the harness over the reference plane, chosen equal to 2.8 cm. Furthermore, since the channel transfer function is likely strongly influenced by the coupling to the other wires in the same bundle, a parametric study has been carried out by randomly chosen the loads on these wires. Four cases are considered in Figure 10 which gives the transfer function between the SPDB and an IBU situated at a distance of 24 m. Either all neighbour wires are terminated on a short circuit (term. 1), on an open circuit (term. 4) or on 50 ? (Term 3). For the final case, half neighbouring wires are loaded with 50 ?, the second half is short-circuited (Term 2).
In Figure 10, we see that when the whole network becomes resonant, terminal loads on all wires modify the S21 parameter. This effect is weaker in DM driving, since in this case, cross coupling with neighbouring wires inside the harness is reduced.
One important feature of the DM excitation is the decrease of the common current Icm propagating along the cable bundle during a PLC transmission. Indeed, this current must not exceed the maximum level of 20 dB?A in a 1 kHz bandwidth, as specified by the DO-160 standards for this type of transmission on the cable network and for its environment. The CM rejection strongly depends on the physical structure of the PLC twisted line and on the symmetry of the input/output transformers. Experiments have shown that a rejection of 20 dB can practically be achieved in the whole PLC frequency band.
These theoretical results have been validated owing to measurement made on the test bench and also compared to measurements on the A340/A600 and on the CLS-CCS demonstrator. EMC aspects as radiation of the PLC link and crosstalk in the CLS harness have been also analyzed.
A software tool allowing the simulation of a PLC transmission, using Orthogonal Frequency Division Multiplexing (OFDM) in a 1-30 MHz band has been developed and an extensive parametric study has been carried out to analyze the performance of the PLC link.
Initially, the selected technology for PLC communication was based on the standard OPERA specifications. Since then, multiple international and industrial standards for PLC have been developed, such as HomePlug AV (HPAV).
Consequently, a first simulation tool was developed, partly in C language and partly under Matlab, to predict the performance of the link under OPERA. A perfect synchronization between transmitting and receiving modems was assumed. The main characteristics of the OPERA standard are a Reed Solomon encoder, a 4D TCM (Four Dimensional Trellis Coded Modulation) and mapping using ADPSK modulation. Among the 2048 sub carriers, equally spaced in a bandwidth either equal to 10, 20 or 30 MHz, only 1536 carriers are used for the transmission. The results of the simulation were obtained by assuming a bandwidth of 30 MHz, called type 1 in OPERA specifications. The complex transfer function deduced either from the theoretical model or from measurements was introduced in the model. Noise was assumed to be an additional white Gaussian noise having a current spectral density of 10 dBµA/kHz. This value has been chosen since the CM disturbing current on the other wires must not exceed 20 dBµA/kHz (DO-160 standards) and the coupling loss between these other wires and the PLC line has been estimated to about 10 dB.
A second simulation tool, based on HPAV has been designed to predict the maximum bit rate to guarantee a Bit error Rate (BER) smaller than a given value. In our simulations, a BER<= 10-3 is chosen for limiting the computation time. In Figure 10, the throughput is plotted versus the common mode current spectral density, assuming a DM excitation. The red curves refer to the 14 modelled channels between SPDB and the IBUs and the blue curves refer to the 16 measured channels in the CLS/CCS demonstrator between PHEU and PTU. For a maximum value of the resulting common mode current of 20 dBµA/kHz (DO160), and considering a maximum BER of 10-3, the throughput of the link varies between 12 and 62 Mbits/s.
Finally, experiments of data transmission have been carried out on the low power test bench with versatile modems (based on FPGAs and following HPAV standards), designed and realized by USTL. The experiments have shown that throughputs greater than 30 Mbits/s are achieved, disturbing noise on the adjacent wires and CM noise due to PLC communication fulfilling the DO-160 standards.
1.3.3 Verification and Validation results
1.3.3.1 Requirements verification
General, Safety and EMC requirements for both TAUPE technologies (PLC and PoD) have been formulated and verified during the project. Not all requirements are applicable or verified for this project. However they may be applicable for a future TAUPE project at a higher TRL level.
The following verification methods were used to determine the compliance with the requirements: Unit Test, System Test, Analysis and Review-of-Design.
Non-compliances were only found in the following areas:
- Some network performance deficiencies as result of the used PLC technology in aeronautical domain;
- Radiated emissions;
- Power supply design;
- Equipment level safety aspects, mainly for PLC.
All these non-compliances have been carefully analysed and studied to propose system improvement. Way forwards have been proposed to successfully comply with identified non compliance.
Currently, the non compliance are considered non critical and are no showstopper for further development.
Regarding the process evaluation, it can be concluded that the process as planned and applied was suitable to verify the TAUPE requirements and to validate the TAUPE system.
The safety approach proposed during the TAUPE project is based on a standard V process. Activities are first performed at system level (CDS and CLS), and then at equipment level (PLC, PoD modems). It is important to note that the proposed process is consistent with the applicable standards of aeronautic systems.
The performed safety analyses describe the capability of TAUPE solutions to respect the aeronautical safety requirements. It has been shown that for safety point of view, the TAUPE PLC and PoD modems are in line with the constraints of the aeronautical domain. No blocking points have been identified regarding the safety level required at equipment level neither for PLC and PoD modems nor, at system level, CLS and CDS systems.
1.3.3.2 Technical maturity reached during the project
The Technology Readiness Level (TRL) scale is a measure to assess the maturity of evolving technology. It was originally developed by the National Aeronautics and Space Administration (NASA). The TRL definition, as it is currently used, consists of nine levels that represent technology growth from the start (basic principles observed) to fully operational use.
The TRL scale used in TAUPE is shown in Table 1, with the TAUPE TRL objective of 4 in bold italics. TRL4 is described as "Basic technological components are integrated to establish that the pieces will work together. This is "low fidelity" compared to the eventual system. Examples include integration of 'ad hoc' hardware in a laboratory."
Moreover, the DoD Technology Readiness Assessment Guidance document provides some additional supporting information for the intended TRL 4: "System concepts that have been considered and results from testing laboratory-scale breadboard(s). References to who did this work and when. Provide an estimate of how breadboard hardware and test results differ from the expected system goals."
Table 1. TRL scale used in TAUPE
TRL
1 Basic principles observed and reported
2 Technology concept and/or application formulated
3 Analytical and experimental critical function and/or characteristic proof of concept
4 Component and/or breadboard validation in laboratory environment
5 Component and/or breadboard validation in relevant environment
6 System/subsystem model or prototype demonstration in a relevant environment
7 System/subsystem model or prototype demonstration in a relevant environment
8 Actual system completed and 'flight qualified' through test and demonstration
9 Actual system 'flight proven' through successful mission operations
The level of maturity can basically be determined by looking at the TRL definitions and deciding which of these best matches the achieved level of the technology. This is a simple and straightforward method. For TAUPE project it is clear that the intended goal of TRL 4 has been reached. However, the determination of the TRL from such a table is not necessarily objective. A tool used to more accurately determine the TRL of technology development is the TRL Calculator from the US Air Force Research Laboratory (AFRL). Using this tool as well, it can be concluded that the maturity level of TRL 4 has been reached, since all hardware TRL 4 questions and even a number of TRL 5 questions could be answered positively.
1.3.3.3 Impact on weight and fuel saving
To estimate the weight of components that can be removed by using PLC technology in an A380, it is considered that CAN, ARINC429 and other communication buses were routed through twin shielded wires. Then, it is considered that twisted shielded databuses were entirely replaced by PLC technology and that mass of the PLC components, PTU (around 20g) and PHEU (between 70 and 90g) were equivalent to existing interface electronic card mass. With those assumptions, the maximum saving potential on A380 is 360 kg.
To generalize the result of using PoAFDX at aircraft level it was decided to compute the weights prorate for the CDS, and to apply it to the systems potentially using the PoAFDX technology. A total of 50 pieces of equipment are eligible to PoAFDX use. The weight of the power cables that could be removed in the eligible systems represents 65 kg on an A380 aircraft. However, the PoAFDX switch size is increased since it embeds new functionality, adding 400 grams more weight to each switch. Also, the converter, filter and injector are evaluated to be 600 grams. Since 16 switches are installed onboard A380, 16 kg shall be added in total. It can be concluded that on an Airbus A380 a weight of 49 kg could be saved if PoAFDX technology is deployed.
The relation between weight and fuel savings on the A320 can be found in document Getting to grips with the A320 Family performance retention and fuel savings, which is publicly available on the internet. Based on the information contained in this document, the weight reductions obtained by using PoAFDX results in minimum 2750$ and maximum 5000$ of annual savings for an A320 flying on a typical sector. The weight savings obtained by using PLC would result in 36 000$ a year for the same aircraft.
1.3.3.4 Benefits in terms of simplification of cabling system, installation, maintenance and retrofit
In case of PLC, the data cables are removed. The power line, currently monofilar (single wire), is either kept as it is, or is replaced by a bifilar version (twin wire). It was shown in the TAUPE project that transmitting data on a monofilar wire do not allow high transmission rates. In addition, the study showed that a bifilar approach without shielding could be used, contrary to common data cables (like those for ARINC 429 or CAN). This can be considered as one connection less, since the braiding does not need to be connected to the connector mass. It simplifies the harness manufacture when the connector is installed during the manufacturing, or decrease the time in assembly line to connect the harness to rear equipment connector.
If it is assumed that the bifilar approach is generalized and the data cables are already a shielded bifilar, then the introduction of PLC replaces one wire (power) + one shielded twisted pair by one twisted pair only. In the case of the CLS, this means 565 links less with PLC than before.
In case of PoD, PoAFDX introduction would lead to power cable removal of 228 meters of cable, which represent 60% gain for CDS specific application.
Heavy maintenance of wiring harnesses is not needed during aircraft life, and harness replacement is very rare once the aircraft definition becomes mature. Therefore, the estimated maintenance simplification potential due to the use of TAUPE technologies is qualitative and cannot be computed. Calculations are equally impossible for retrofit benefits as well. When retrofitting an aircraft, the main cost is due to the time needed to design, manufacture and install the harness. The cable simplification seen above is low compared to this main cost but it certainly would bring benefit for retrofit.
1.3.4 Conclusion
TAUPE has introduced verified and validated PLC (Power Line Communication) and PoD (Power over data) technology inside the aircraft, to supply power and data over the same cable, replacing two cables with a unique one. The project partners have defined the requirements and the optimal architecture of the PLC and PoD systems, to make it suitable both for existing aircraft (for retrofit purposes) and for coming generations of composite aircraft.
An extensive modelling/simulation activity has been performed, and a simulation tool was produced and used to predict the feasibility and performances the technologies. Based on this work and taking into account aeronautical standards, components were designed and adapted for two systems Mock-Ups: A Cabin Lighting and Communication system, verifying and validating PLC technology, and an A380 Cockpit Display System Mock-Up, verifying and validating PoD technology. Validation of the test-benches has been performed and the security aspects of the systems assessed. Both CLS and CDS were shown to be compliant with all safety requirements and confirming the result maturity at TRL 4.
Thanks to TAUPE results (the outcome of TAUPE in terms of cable saving potential is a weight reduction of 359 kg and 36km less cable for an A380 aircraft, whereas the potential fuel savings on a single A320 aircraft would amount to 36 000 $/year), several benefits can now be expected, mainly in the environmental area as reduced weight means reduced fuel consumption. However, benefits are also economic, since cable fitting, maintenance and retrofit can be simplified and cost effective by reduced cabling.
Potential Impact:
1.4 Potential impact
The TAUPE results are paving the way to innovative full avionic architecture mixing aircraft electrical and communication networks. The resulting association with related specifications (harness wiring, network equipment), related requirements (system qualification) and the related technologies will allow easy, rapid and secure integration of on-board electrical systems.
The technologies used by the project are PLC & PoD, integrated in equipments and components compliant with aircraft constraints and safety requirements. Beyond enabling the All Electric aircraft and the integration of on-board electrical systems, TAUPE results will also enable the reduction of operating cost through reduction in fuel consumption (approx 180 tonnes of fuel saved for the A320 fleet) and other following direct operating cost. It will then be possible for airlines companies to reduce travel charges accordingly.
This project has been conducted in line with ACARE Strategic Research Agenda 2 (High Level Target Concept The Highly Cost Efficient Air Transport System) and in particular in line with the activities envisaged in the frame of the System for green operations of JTI CLEAN SKY and with Vision 2020 goals. TAUPE has participated to enable the Cost effective aircraft by providing innovative responses to aircraft challenges, such as solutions to reduce wiring on board, in order to save weight & cost. This research will allow reduction of a large number of connections and tests in the final assembly line of future aircraft, the simplification of system design architectures and maintenance. This has positive impact on security, cost and time issues.
TAUPE has provided benefits to citizens, society and climate, considering the potential weight reduction of future aircraft. The results show a measurable potential reduction of fuel consumption, as well as CO2 and NOx emissions. The cost effective retrofit capacity will allow current airlines fleets to become greener aircraft and this has an impact on aircraft life cycle.
The project has supported competitiveness of European industries in the global market by guaranteeing safety (design robustness able to meet certification requirements), industrialisation and the related costs and portability to other equipment. A contribution to the production of electric and telecommunication standards has also been made.
By widely disseminating its results through public forum and strong relationships with FP6 and FP7 project and CLEAN SKY, TAUPE has also participated to strengthen the competitiveness of the European supply chain.
1.5 Dissemination activities
TAUPE partners have been committed to widely disseminating the technical assessment of the project to suppliers, SMEs, Academics and Research centres.
Dissemination activities in TAUPE were focused on 3 main objectives:
- Ensure the TAUPE resulting technology will be brought to higher TRL level (6-7) as part of the project exploitation
- Strengthen the competitiveness of European Aero-systems Industry and its supply chain for integration of new technology in products
- Strengthen academics and Research centres awareness, knowledge and efforts to support the aero-systems sector in future programme
These objectives were achieved through the following dissemination actions:
- Exchanges with stakeholders for standardisation purposes and dissemination of results and knowledge
- Public events (M18 and M42)
- Dissemination materials
- Scientific and Technical publications
- Public website with contact details
1.5.1 Exchanges with stakeholders for standardisation purposes and disseminate TAUPE results and complement knowledge
For the time being, the work within the well-known established standardisation organisations, for example EUROCAE, IEEE or ARINC, is primarily focussing on interworking, interoperability, co-existence aspects rather than on common harmonised standards. TAUPE, a project at TRL4, has therefore focused its effort on demonstrating the certificability of its results developed from existing standards (e.g. OPERA).
In preparation of a follow-up project maturing current results to a higher TRL level, frequent communication of the TAUPE results in the presence of standardisation stakeholders have been undertaken in order to raise awareness of recent progress in the field.
1.5.2 TAUPE Dissemination Events
TAUPE has organised 2 dedicated public dissemination events (M18 and M42) to present the main project results and technology benefits to the aeronautics industry, academia and research centres, and gathering 150 attendees from Europe and North America.
1.5.2.1 M18 Dissemination event
This first dissemination event was organised in conjunction with the Avionics Europe 2010 conference and exhibition, in order to attract attendees as much as possible.
It took place in Amsterdam, March 25, 2010 and presented (Figure 13) the M18 results of the TAUPE project with:
- PLC investigation on Low Power Test Bench, representative of the reference applications installed in the aircraft
- Techniques to reduce common mode current & radiated emissions
- Numerical assessment of channel properties for future application and use of PLC in Aircraft
- Feasibility and performances of a PLC Communication
- Bifilar approach
- Feasibility of PLC in the context of aircraft cabin
- Safety Approach
- Verification and Validation aspects
The overall achievements of this event were:
- TAUPE results have raised awareness of stakeholders (Aeronautics, surface transport and Space) and made them aware of TAUPE partners competencies
- Exploitation of results and/or continuation of the project concepts beyond TRL 4 are strengthened with several contacts initiated for further discussions
1.5.2.2 M42 Final dissemination event
The final dissemination event, held in Paris, 15 February, 2012, presented the results of the TAUPE project with:
- PLC RTD developments on Cabin Mock-Up, including the cabin light system and communication system, demonstrated on site (Figure 14)
- PoD RTD developments of Cock-pit Display System on A380 Test-bench
- TRL reached by the project and the results qualification towards Certification and Safety
- Assessment of results against Cost effective Aircraft with calculated savings on weight and fuel as well as positive perspectives for maintenance and assembly
This event was very successful with the presence of the EC, the press, and fruitful questions/answers sessions raising opportunities for exploitation and future project to maturate the TAUPE.
The overall achievements of this event were:
- TAUPE results have raised awareness of stakeholders and made them aware of TAUPE partners competencies
- Technical feasibility, reliability and safety of PoD and PLC have been demonstrated
- Exploitation of results and/or continuation of the project concepts beyond TRL 4 are strengthened with several contacts initiated for further discussions
1.5.3 Project presentation material
In order to convey a professional and consistent image of the project, basic presentation material to support information dissemination actions, such as a project logo, letterhead and presentations template, was provided at the beginning of the project. Posters, Pop-up banners and flyers and information leaflets were produced and distributed, both at TAUPE events and major aeronautics events where TAUPE partners participated, such as the ESA Workshop on Aerospace and Singapore Air show. This material has delivered messages targeting the expected attendees to such workshops: environmental concerns, cost saving and innovation.
1.5.4 Scientific publications and presentations in key journals and aeronautic conferences.
The academic partners involved in TAUPE have published frequently in peer-reviewed journals with international scope, such as IEEE transactions and magazine on aerospace and electronics system, IEEE transactions on EMC, IEEE transactions on power delivery and IEEE transactions on communication.
Both academic and industrial TAUPE partners have also actively participated in conferences and workshops relevant for TAUPE purposes. These network activities have been important to avoid duplication of research activities and to raise awareness about PoD and PLC technologies evolution.
1.6 Public website and contact details
The public website on the TAUPE project is accessible at: http://www.TAUPE-Project.eu
The Taupe public website has been visited 6.791 times by 4.449 unique visitors. As an average, each visitor is viewing 3,85 pages per visit, the most popular page is the page where publications and presentation can be downloaded.
Most visitors connected from:
1/ France,
2/ Germany
3/ USA
The analysis of the domains connected showed that industrials (airframers and systems providers) are regular visitors. Mainly used to widely disseminate project results as well as the proceedings from the public dissemination events (M18 and M42), the Taupe public website also contains a presentation of the TAUPE project, key figures, the presentation of the project partners with contact details.
List of Websites:
Public website: http://www.TAUPE-Project.eu
The TAUPE coordinator is:
François Gogé,
Technical Director
SAFRAN ENGINEERING SERVICES
The TAUPE partners are:
AIRBUS OPERATIONS SAS
316 route de Bayonne
31060 Toulouse cedex 09
France
ARTTIC
58a, rue du Dessous des Berges
F-75013 Paris
FRANCE
DIEHL AEROSPACE
Donaustrasse 120
D-90451 Nürnberg
Germany
EADS Deutschland GmbH
Sensors, Electronics & Systems Integration
Dept.TCC4/ IW-SI EC
81663 Munich
Germany
Ecole Polytechnique Fédérale de Lausanne (EPFL)
Swiss Federal Institute of Technology - EMC Group
EPFL-STI-LRE, ELL-138, Station 11
1015 Lausanne
Switzerland
EKIS
31st Dionisie Lupu street, 2nd floor, 3rd apartment, 2nd District
020021 Bucharest
ROMANIA
Haute Ecole dIngénierie et de Gestion du Canton de Vaud (HEIG)
Institute for Information and Communication Technologies
Route de Cheseaux 1
1400 Yverdon-les-bains
Switzerland
HISPANO SUIZA
18, Boulevard Louis Seguin
92707 Colombes Cedex
France
Hochschule Luzern Technik & Architektur (HSLU)
Technikumstr. 21
6048 Horw
Switzerland
HORTEC BV
Zutphenstraat 53
7575 EJ Oldenzaal
Netherlands
ONERA
DCV/SGA
2 avenue Edouard Belin, BP 4025
31055 Toulouse Cedex 4
France
LABINAL/SAFRAN Engineering Services
Victoria Centre 2
20 Chemin de Laporte
31300 Toulouse
France
Stichting Nationaal Lucht- en Ruimtevaartlaboratorium (NLR)
Voorsterweg 31
8316PR Marknesse
Netherlands
Thales Avionics
105, av. du Général Eisenhower
BP 63647
31036 Toulouse cedex 1
France
Université des Sciences et Technologies de Lille (USTL)
U.S.T.L. Lille 1 - IEMN/UMR 8520
Bâtiment P3
59655 Villeneuve d'Ascq
France
