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Scope of the DRESS project is to research, develop and validate a distributed and redundant electrical steering system technology for an aircraft nose landing gear. The new system aims to: • reduce system weight at aircraft level, replacing the current hydraulic actuation system with an electric one. • improve aircraft safety, achieving higher system redundancy levels compared to the current technology capabilities. This paper presents an outline of different activities occurring in the DRESS project and also shows preliminary results of the new system performance.

The presented paper introduces the new software complex aimed at simulation of the riveting process as applied to aircraft parts. The software complex implements the novel mathematical model based on minimization of the potential energy. The paper gives the detailed description of the mathematical model and particularizes the main features of the software. The physical and numerical tests aimed at validation of the software are also described in the paper.

Edgewater's RTEdge™ Platform toolset is a model driven development environment for mission critical real-time systems. Using precise execution semantics and mathematical proof-based analysis, RTEdge™ enables the verification of critical properties of systems with high assurance. This case study will follow the design and implementation life-cycle of a system representing a real-world, mission critical domain: airborne electronic warfare. Using examples and constraints taken from this system, software components will be built to illustrate the principles of architectural conformance, timeliness and testing as executed within a static analysis framework. Using RTEdge™ as an example, this case study will introduce the concepts of model driven development in software and demonstrate how static analysis can be used to verify characteristics of a system that are traditionally left for later stages of development.

Requirements analysis for aircraft simulators is often driven by photographs and videos of the actual aircraft. An engineer may gather and organize hundreds or even thousands of source photos of various instruments and devices unique to the aircraft. Managing all of this source information and referencing it to generate software requirements can be challenging and time-consuming. This paper explores Content Based Image Retrieval (CBIR) techniques to automatically process and search those images to generate basic requirements and to facilitate reuse. An unsupervised clustering algorithm groups source images based on minimal user input. Images processed in this way can also be queried by image similarity, thereby allowing project managers to find common source material among projects. The effectiveness of these techniques is demonstrated on an example cockpit.

Whether it be in highly visible features like fascinating new infotainment systems or hidden behind the scenes in complex new hybrid powertrain controls, in-vehicle software is rapidly changing the way the automotive industry engages its vehicle-buying customers. In every application where a compelling new electronic solution is emerging, it is enabled by the convergence of in-vehicle software developed by different collaborating partners. As more and more component suppliers, vehicle OEMs, and technology vendors enter into collaborative software development projects with each other, a new set of technical and business challenges are showing collaborative software development to be a very distinctive proposition than traditional stand-alone development.

A simulation framework for vehicle aerodynamics using up to 10 billion fully unstructured cells has been developed on a world-fastest class supercomputer, called the K computer, in Kobe, Japan. The simulation software FrontFlow/red-Aero was fully optimized on the K computer to utilize up to 10,000 processors with tens of thousands of cores. A hybrid parallelization method using MPI among processors and OpenMP among cores inside each processor was adopted. The code was specially tuned for unsteady aerodynamic simulation including large-eddy simulation, and low Mach number approximation was adopted to avoid excessive iterations usually required for the fully incompressible algorithm. The automated mesh refining system was developed to generate unstructured meshes of up to 10 billion cells. In the system, users only generate unstructured meshes in the order of tens of millions of cells directly using commercial preprocessing software.

For decades optical camera systems have been used by Broetje-Automation to locate pilot holes and find product orientation on NC-controlled positioner systems. Measurement tolerance requirements were and are in the range of +/− 0.2 mm. Recent developments enhance the sensor technology function from pure hole detection to new features like Fastener Head Height Measurement and Countersink Diameter Measurement. While head height measurement has to go 3D by enhancing the planar sensors to head protrusion measurement, the Countersink measuring tolerances are much smaller than “simple” hole detection, in fact require more than a magnitude tighter tolerances. This paper will present how Broetje-Automation solved the issue of a 20 plus fold accuracy increase, the 3D capability of the one eyed camera and all accompanied by a more robust evaluation software.

ECOA is an active software architecture research programme conducted by the French Republic and United Kingdom. It is one product of the recent Defence and Security Co-operation Treaty signed between the two nations. This paper provides an overview of the programme goals and progress as well as an introduction to the technology being developed and comparison to related initiatives. The goal of the ECOA programme is to define an open software architecture that enables collaborative development of mission system software. The ECOA programme is needed to reduce development and lifecycle costs of future military air programmes. For this reason the programme has a specific focus on combat-air mission systems but the underlying technology is general purpose, applying to multiple military and civil domains. At present, the programme has defined a concept, delivered a set of initial technical standards and produced a joint demonstrator to validate the technology developed.

Locked wheel protection is an important part of antiskid control for aircraft brake control system. Locked wheel protection compares the wheel speed of two or more wheels, if one of the wheels is too slow, locked wheel protection releases the brake pressure on the slow wheel. This work aims to study the control logic for locked wheel protection. Locked wheel protection control logic consists of 3 key factors: paired wheels, active threshold and inhibit velocity. Focus on comparison different options of these 3 factors, all aspects of control logic for locked wheel protection had been expounded in this study. Simulation and calculation analysis is applied for different locked wheel strategies to evaluate the effect. One conclusion is that the greatest wheel speed of the wheel under control shall be set as a reference speed for locked wheel protection. This study provide the basis to design a proper locked wheel protection function of aircraft brake control system.

Aircraft cabin systems, especially cabin management systems (CMS) have to cope with frequent cabin changes during their lifecycle. This includes not only layout rearrangements and technological upgrades during the service, but also extensive CMS customizations and product variations before aircraft delivery. Therefore it is inevitable for the CMS to be highly changeable and offer an easy and agile change process. Today's CMS solutions face this challenge with configurable system architectures. Although such architectures offer a vast change domain, they usually come with time consuming and error prone change processes. This paper introduces an adaptive avionics software architecture that enables the CMS to cope with cabin changes highly automatically and with minimal human interactions. The adaptation is performed during an on ground organization phase, in which system changes are detected and evaluated by the CMS itself.

Composites are becoming a common material for aero structures; that means new manufacturing processes with new problems and new challenges have to be solved. Our engineering team (EiNA) has recently developed and patented a new end effector for Robots that is able to track any kind of surface (even if the surface is moving, swinging, bending….which usually happens when working with big composite parts.) and carry out the required task. This new feature has enabled robots to automate manual tasks that hadn't been automated jet like sanding, cleaning, polishing, applying solvents, applying release and cleaning agents not only on aero structures but also on its molds. The solution is based on a set of sensors, a postprocessor which runs a software and a mechanical compensation gadget. As a result, we can keep all the parameters of a process fully under control even if the part we are working on is not stable and it moves swings and bends.

In the aerospace industry, methods for virtual testing cover an increasing range of test executions carried out during the development and test process of avionics systems. Over the last years, most companies have focused on questions regarding the evaluation and implementation of methods for virtual testing. However, it has become more and more important to seamlessly integrate virtual testing into the overall development process. For instance, a company’s test strategy might stipulate a combination of different methods, such as SIL and HIL simulation, in order to benefit from the advantages of both in the same test process. In this case, efforts concentrate on the optimization of the overall process, from test specification to test execution, as well as the test result evaluation and its alignment with methods for virtual testing.

“Embedded Software Build” is the process of taking all source code files that are part of the embedded system and compiling them into build artifacts, such as executables or binaries for the target embedded hardware. In the case of embedded systems, it includes low level software for a specific embedded hardware device, the application software and the associated application data. To further complicate this, low level software also known as firmware or middleware layers are often hand-coded while the application layer is auto-coded. To ensure build reproducibility, accurately predict build results and achieve error-free embedded software builds both in a lab environment and in the field, embedded software builds are required to be automated. At the very initial stage of the project, we realized that the automation of the Embedded Software Build is highly imperative and extremely crucial, as we're dealing with a Real Time - Safety Critical - Aerospace Embedded System.

Ground Vibration Testing (GVT) of aircraft is typically performed very late in the development process. Main purpose of the test is to obtain experimental vibration data of the whole aircraft structure for validating and improving its structural dynamic models. Among other things, these models are used to predict the flutter behaviour and carefully plan the safety-critical in-flight tests. Due to the limited availability of the aircraft for a GVT and the fact that multiple configurations need to be tested, an extreme time pressure exists to get the test results. The aim of the paper is to discuss recent hardware and software technology advancements for performing a GVT that are able to realize an important testing and analysis time reduction without compromising the accuracy of the results.

The purpose of this paper is to compare classical handbook methods used to predict performance parameters such as range and endurance to computer based methods. Three different methods are compared: classical handbook methods are based on simple drag polars and engine performance data, spreadsheet methods use more detailed engine data and drag polars and third is the use of APP (Aircraft Performance Program), a commercially available software program. The advantages and disadvantages of each method are described and accuracy listed based on existing airplanes. One example is used: a business jet type aircraft. Methods used are described and inputs and outputs of the different programs used are shown.

The paper presents an innovative approach for the functional specification of complex and highly integrated aircraft control systems, such as the Environmental Control System (ECS), by applying model based specification methods. Complexity and effectiveness of modern ECS have significantly increased during the last few years along with development of new technologies and innovations in control engineering as well as digital data distribution and processing. Efficient management of cabin air flows on the one hand makes the ECS more energy-saving and on the other hand more complex with regard to its functionality and interaction with other interfaced aircraft systems. Numerous data interfaces to other systems and a high degree of automation are typical for a modern ECS. The aircraft manufacturer specifies the entire ECS functions and its interactions within the aircraft.

Edgewater Computer Systems Inc. product RTEdge™ Platform 1.2 is a software toolset supporting proof-based engineering, implementation and deployment of software components, built using the RTEdge™ AADL Microkernel modeling subset. This is a small subset of the AADL component model and execution semantics, covering threads and thread-groups communicating solely through asynchronous event ports and through explicitly shared data ports. Threads behavior is expressed as state machines and dispatch run time semantics is encoded in a Run-time Executive, enforcing pre-emptive priority dispatch based on statically assigned event priorities, with ceiling priority protocol access to shared data. This simple AADL microkernel semantic core can support all dispatch policies, communication and synchronization mechanisms of a fully fledged AADL run time environment, permitting the systematic use of the RTEdge™ static analysis tools for AADL-compliant software components.

Tube Launched-Unmanned Air Vehicles (TL-UAV) are munitions that alter their trajectories during flight to enhance the capabilities by possibly extending range, increasing loiter time through gliding, and/or having guided targeting capabilities. Traditional munition systems, specifically the tube-launched mortar rounds, are not guided. Performance of these "dumb" munitions could be enhanced by updating to TL-UAV and still utilize existing launch platforms with standard propellant detonation firing methods. The ability to actively control the flight path and extend range of a TL-UAV requires multiple onboard systems which need to be identified, integrated, assembled, and tested to meet cooperative function requirements. The main systems, for a mortar-based TL-UAV being developed at West Virginia University (WVU), are considered to be a central hub to process information, aerodynamic control devices, flight sensors, a video camera system, power management, and a wireless transceiver.

As the US is getting ready for the Next Generation (NextGen) of Air Traffic System, there is a growing concern that the current techniques for verification and validation will not be adequate for the changes to come. The JPDO (in charge of implementing NextGen) has given NASA a mandate to address the problem and it resulted in the formulation of the V&V of Flight-Critical Systems effort. This research effort is divided into four themes: argument-based safety assurance, distributed systems, authority and autonomy, and, software intensive systems. This paper presents an overview of the technologies that will address the problem.

Critical systems are subject to drastic certification constraints (DO178-B for avionic systems, SIL-4 for railway systems, ISO26262 for the automotive domain), which require system providers to produce strong evidence for the correctness, reliability, or performance of their systems. Today, the early use of formal modeling and verification methods is recognized as favorable by the industry. Formal methods, which started to appear in the 60's, have now reached a maturity level allowing them to be used in an industrial context. The approach of control system modeling as proposed by the MathWorks with MATLAB Simulink, by Esterel Technologies with the SCADE language or by the academic community with the Lustre language, is extensively used for reactive systems design and often allows the automatic generation of the embedded code.