SCOPE PRESENTATION INTRODUCTION Introduction My position within Airbus: Working in the Modeling and Simulation (EYYS) department of Engineering. In charge of the AP2633 standard and all the associated processes, methods and tools. Presentation objectives This presentation aims at describing the reasons and the way Airbus has parameterized and is using: Simulink, Simulink Coder (previously RTW), and soon Embedded Coder (E-Coder), To design and to generate Aircraft System, Equipment and Environment Simulation Models in compliance with the rules of the Airbus Procedure 2633 Develop, Integrate & Validate Shared Simulation Models, usually called AP2633. TRANSITION TO THE NEXT SLIDE THE USE OF SIMULATION MODELS WITHIN THE AIRCRAFT DEVELOPMENT PROCESS Page 1
SCOPE AIRCRAFT SYSTEMS/EQUIPMENTS INTEGRATION Simulation Models use along the aircraft development process Simulation Models are used all along the Aircraft development process and mainly during Integration, Verification & Validation activities, but also for training purpose. Simulation Models development and supply To do so Simulation Models are either developed by Airbus or requested, through contract, to Suppliers (Rolls-Royce, Pratt & Whitney, Thalès, DIEHL, Honeywell, Hamilton, LIEBHERR, or even EADS) in complement of their system/equipment delivery. From Simulation Models to real system(s)/equipment(s) Represent all or part of aircraft system(s)/equipment(s) as well as the environment in which the model is moving (on ground: runway, winds, ; in flight: atmosphere, winds, ). Are used to prepare aircraft system(s)/equipment(s) integration, integrated incrementally by Airbus. The integrated models allow to check the consistence, in terms of interface as well as of functional behavior, of the built assemblies. Will be progressively replaced by real system(s)/equipment(s) to go smoothly from a virtual integration to a real one. TRANSITION TO THE NEXT SLIDE USE OF SIMULATORS ALONG AIRCRAFT VERIFICATION AND VALIDATION PROCESS Page 2
SCOPE AIRCRAFT SYSTEMS/EQUIPMENT VERIFICATION & VALIDATION Simulation Models Use Simulation Models participate to the different V&V phases by being used on different test means (System integration benches, functional integration benches and simulators) used all over the V life cycle. They are used to perform Verification & Validation tests of the aircraft systems/equipments integrated consistently with the aircraft architecture. Simulators all along the aircraft Verification & Validation process Different kind of simulators are used all along the V&V process: Desktop Simulators (DTS) during design phases, Virtual Simulation platforms (A/C-1: The development Simulator, VIBE, VIP) for integration and verification tests, Systems Integration Benches (SIB), Functional Integration Benches (FIB), Integration (CAB0, I/S: The integration Simulator) and aircraft Simulators (A/C0: I/S + Iron Bird) and training platforms made by Simulator Manufacturers (CAE, ) TRANSITION TO THE NEXT SLIDE THE NEED TO SHARE THE SAME SIMULATIONS MODELS ALL ALONG THE PROCESS Page 3
SCOPE The AP2633 Standard Why AP2633? The AP2633 standard was built on the basis of a Lessons Learnt process led in 2000 in Airbus. This one highlighted that, even if Simulation Models are used all over Airbus, these are different and not easily shared by the different customers on the different simulators and/or test means used all along A/C IVV Process. This pointed out that the Simulation Models: are developed several times for use on different means inducing redundant costs, don t have the same representativeness, since not based on shared requirements, making difficult to cross-check/compare obtained behaviors/results, are not built with the same software rules, making their integration complex and each time different on each environment To solve the identified issues, it was decided to define and promote a standard enabling all the A/C IVV stakeholders to share the same Simulation Models all over their means: the AP2633. This standard focuses on: A Simulation Model development process based on a simplified V life cycle going from requirements collection to model delivery A single Simulation Model, developed once, covering all Simulation requirements and guaranteeing the right representativeness for all customers Design Rules that mainly address the way the Simulation Model high-level interfaces - Control, Functional and Profile Inputs/Outputs, main Entry-point are defined A standard integration process based on standardized interfaces: the Model ICD (Interface Control Document) and its associated software representation. TRANSITION TO THE NEXT SLIDE WHAT IS THE LINK BETWEEN A SIMULINK AND AN AP2633 MODEL? Page 4
SCOPE THE LINK BETWEEN A SIMULINK MODEL AND AN AP2633 MODEL Why an AP2633 solution for Simulink Since the very first deliveries of AP2633 Simulation Models, we have noticed that many of them were designed and generated using Simulink. Such a approach could be understood if you think that people developing Simulation Models are more business oriented (Systems Designers for flight control, hydraulic, pneumatic, electrics, ) than Software skilled. Such a work requires also simulation competences to implement adequate solutions. Consequently, to avoid different production processes and solutions, it was decided to formalize a solution that could be provided to our suppliers. This one would avoid to adapt any different processes implemented by any of our suppliers. Design of an AP2633 Simulation Model using Simulink Simulink could be used to design any System(s)/Equipment(s) AP2633 Simulation Models. As an AP2633 Simulation Model has to be exchanged under their software shape (either source or binary code), but respecting high-level interfaces identification through the production of formal deliverables, the Simulink Model shall be colored/marked in order to be able to clearly identify these interfaces. On Airbus side, exchanging generated software rather than the Simulink Models allows us not to have to deal with code generation constraints. The characteristics to be shared between a Simulink Model and an AP2633 Model AP2633 Simulation Models are black-box models, managed through their high-level interfaces: control, functional & profile. They are fixed step models for which the simulation time step is a dedicated control input of the model. They are designed that way that the simulation step is able to be modified along a simulation session. TRANSITION TO THE NEXT SLIDE THE AIRBUS SOLUTION TO SUPPORT THE AP2633 SIMULATION MODEL DESIGN WITH SIMULINK Page 5
SCOPE THE SL2AP2633 TOOL TO DESIGN AP2633 SIMULATION MODELS The management of the Simulation Model high-level interfaces Dedicated blocks were created either to be able to use the AP2633 control models or to mark the Simulation Model functional interfaces The management of the Simulation Model high-level interfaces A Library of AP2633 compliant (regarding time management) operators is also made available The main drawback of this solution management The blocks to be used to mark the high-level interfaces are not easy to manage since not simple automated process has been provided to define them. These blocks may disturb the correct simulation of the Simulink Model. TRANSITION TO NEXT SLIDE HOW TO MANAGE, IMPLEMENT AP2633 IMPROVMENTS TAKING BENEFIT OF SIMULINK EVOLUTIONS Page 6
SCOPE THE SL2AP2633 IMPROVEMENT PROCESS Initially As it was stated that many AP2633 Model developers were using Simulink to develop and generate AP2633 Simulation Models, SL2AP2633 tool was developed since early 2003, and distributed to end-users late 2003, on the basis on Matlab r12. Until now Matlab r12, r13, r14, R2006b, R2007b, R2008b, R2009b, R2010b, Until SL2AP2633 v4.5.2 Windows/Unix version Static/Dynamic Targets S-functions Reference Models Compatibility with Simscape To come in the near future For SL2AP2633 v5.1 under development Simulink Objects To come later on 2013 Embedded Coder To come later on How to take benefit quickly/easily from MathWorks evolutions? How to support the AP2633 standard evolutions? AP2633/B supported only AP2633/C + M2633.2 to be supported in the next versions TRANSITION TO THE NEXT SLIDE THE NEXT SL2AP2633 TOOL VERSION AS AN EXAMPLE Page 7
SCOPE THE NEXT SL2AP2633 TOOL VERSION, v5.1, TO COME Upgrade of the interface management The AP2633 blocks used to mark the Simulation Model interface have been replaced by Simulink objects. Benefits The automation (scripting) and use of the interface management is more simple. Moreover, the building of test harnesses - within Simulink - is simplified and no disturbance any more due to the presence of extra blocks. TRANSITION TO THE NEXT SLIDE FROM DESIGN TO CODE GENERATION Page 8
SCOPE AP2633 SIMULATION MODEL SOFTWARE GENERATION WITH SIMULINK AUTOMATIC CODE GENERATOR Source Code generation using Simulink Coder A dedicated HMI has been developed in the frame of SL2AP2633 tool in order to be able to select the main necessary options for the generation of an AP2633 Simulation Model: Configure model: to apply SL2AP2633 settings for code generation Simulink Model name (and file) Delivery directory: for MICD, source code, AP2633 interface files, standalone model, makefile example, compilation flags file generation MICD csv files separator, AP2633 V_MODEL_ID buidling information: Model Name + Model code version Generate Model ICD Generate Code: source code, AP2633 interface files, standalone model, makefile example, compilation flags file generation S-functions code directories, Inline parameters, Line command selection Generation target: static, dynamic AP2633 target or other Code generation with/without compilation AP2633 Interface files generation: CTRL_C, DATA_C, PROFILE_C Why moving to a source code generation using E-Coder The size of the generated source code is reduced by 2 and the execution timed divided by almost (depending also on compilation optilmzation options) Such a strategy requires also to intensively use available Simulink concepts as atomic or reference model. The generator will be integrated in next version to allow a better generation tuning and enhanced execution performances highly requested by engine models developer/users at least. Notice Generated Code used for the simulation only for the Simulation Models generation used in the frame of the aircraft IVV. TRANSITION TO NEXT SLIDE END OF THE STATE OF THE ART WITH AN OUTLOOK TO THE NEAR FUTURE Page 9
SCOPE SYNTHESIS ON THE CURRENT SOLUTION The current SL2AP2633 limitations Each new MATLAB Simulink release requires us an extra effort of validation, just to ensure that the tool is still behaving the same way according to the latest changes/evolutions. Moreover, we need to offer an ascending compatibility with the existing versions for a set of MATLAB Simulink predefined releases. The envisaged way forward To include an AP2633 target, as well as the necessary blocks/objects, as a native solution within Simulink in order to ensure the best implementation solution at any time and avoid a huge volume of nonregression tests. This solution will aslo be a major benefit for all the Airbus suppliers which have to provide us AP2633 Simulation Models design and generated with Simulink. To use Simunlink as a desktop pre-integration platform of AP2633 Simulation Models. Such a target requires to define a standard way to generate the AP2633 Models into software code, but also to be able to build a Simulink Model for instance, a S-function from a standard AP2633 software code. It requires also to be able to build Simulation Models connections on the basis of standard interface descriptions (MICD). TRANSITION TO NEXT SLIDE Q&A Page 10
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