Avionics Platform Research Articles

PulseAnomaly: Unsupervised Anomaly Detection on Avionic Platforms with Seasonality and Trend Modeling in Transformer Networks

PulseAnomaly: Unsupervised Anomaly Detection on Avionic Platforms with Seasonality and Trend Modeling in Transformer Networks

OD1NF1ST: True Skip Intrusion Detection and Avionics Network Cyber-attack Simulation

MIL-STD-1553 is a communication bus that has been used by many military avionics platforms, such as the F-15 and F-35 fighter jets, for almost 50 years. Recently, it has become clear that the lack of security on MIL-STD-1553 and the requirement for internet communication between planes has revealed numerous potential attack vectors for malicious parties. Prevention of these attacks by modernizing the MIL-STD-1553 is not practical due to the military applications and existing far-reaching installations of the bus. We present a software system that can simulate bus transmissions to create easy, replicable, and large datasets of MIL-STD-1553 communications. We also propose an intrusion detection system (IDS) that can identify anomalies and the precise type of attack using recurrent neural networks with a reinforcement learning true-skip data selection algorithm. Our IDS outperforms existing algorithms designed for MIL-STD-1553 in binary anomaly detection tasks while also performing attack classification and minimizing computational resource cost. Our simulator can generate more data with higher fidelity than existing methods and integrate attack scenarios with greater detail. Furthermore, the simulator and IDS can be combined to form a web-based attack-defense game.

Simplified Fe modeling of the PyCubed PCB complete with components for CubeSat missions

CubeSat nano-satellites are, to date, the cheapest independent mean of bringing a payload into orbit. The most frequent cause of failure for this kind of launches is the mechanical failure of electronic boards or soldered electronic elements due to vibrations or shocks. For this reason, the numerical finite element design and experimental verification phases of printed circuit boards (PCBs) with soldered components are extremely delicate and critical in the assessment of the integrity of the boards during launch. In simulating the mechanical behaviour of PCBs it is important to consider the material properties, the geometry, and the type of components mounted on them. Possibly the most widely used open-source CubeSat PCBs are the PyCubed. While these avionics platforms, programmable entirely in Python, are radiation-tested and integrate many control features into a single low-cost PCB, they lack of a proper mechanical characterization. Indeed, we believe that the knowledge of the dynamic behaviour of this PCB is crucial to achieve high-reliability CubeSats and to improve the mission success rates. For this reason, this paper will not only provide a mechanical and physical characterization of the PyCuded open-source printed circuits; but above all, it will generate an innovative simplified and reliable numerical model of the PCB that reflects the dynamic behaviour of the complete motherboard of components during the launch. To support and to complete the analysis, numerical/experimental modal comparisons will be used to validate the proposed models. In this way, all designers of PyCubed PCBs will be able to simulate, as realistically as possible, the complete mechanical behaviour of the printed circuit in the presence of components, reducing time, costs, and design risks. The approach the authors proposed, could also be used to model other generic types of printed circuits boards.

Secure communication technology between network domains based on virtualization avionics platform

In the information interconnection scenario of the new generation wide-body aircraft, there is a large amount of real-time bi-directional data exchange between aircraft control domain and airline information services domain in civil aircraft avionics system, and its security isolation and information flow protection are facing increasingly serious information security threats. Therefore, a bi-directional secure communication architecture based on virtualization avionics platform is proposed in this study. The attribute-based access control for multiple avionics domain is modeling and the designs of protection for contract security critical data and real-time monitoring for security critical component effectiveness are given. Physical implementation and verification results based on the domestic ACoreOS operating system and avionics hardware platform show that the bi-directional secure communication method based on virtualization avionics platform achieves the spatial isolation of security critical components, the data transmit and receive time of ACD network is less than 50 ms, and the message transmit and receive rate of ACD network is greater than 70 Mb/s. These results can meet the performance requirements of secure communication between avionics network domains of wide-body aircraft, which have high practical value.

Exploiting the MIL-STD-1553 avionic data bus with an active cyber device

The ensemble of cyber and electromagnetic activities has become predominant in present-day battlegrounds and armed forces are witnessing the introduction of complex and interconnected weapon systems. According to United States military doctrine, cyberspace has been classified as the fifth dimension of the battlespace and much effort is being devoted by NATO to secure activities in such an environment. This paper delves its roots in a vast research endeavor aimed at granting cyber resilience of current and future assets. Within such a broad and challenging domain, the work has a very precise scope: to address the vulnerabilities of a specific avionic platform protocol, namely the MIL-STD-1553 standard. The discussion will unfold into the design and implementation of a cyber device that is able to exploit the identified vulnerabilities. The device in question will also be tested to prove the effectiveness of the proposed solution. The outcomes will stand as a call to action towards improving the security of state-of-the-art avionic systems.

Intrusion Detection System for the MIL-STD-1553 Communication Bus

MIL-STD-1553 is a military standard that defines the specification of a serial communication bus that has been implemented in military and aerospace avionic platforms for over 40 years. MIL-STD-1553 was designed for a high level of fault tolerance while less attention was paid to cyber security issues. Thus, as indicated in recent studies, it is exposed to various threats. In this article, we suggest enhancing the security of MIL-STD-1553 communication buses by integrating a machine learning-based intrusion detection system (IDS); such anIDS will be capable of detecting cyber attacks in real time. The IDS consists of two modules: 1) a remote terminal (RT) authentication module that detects illegitimately connected components and data transfers and 2) a sequence-based anomaly detection module that detects anomalies in the operation of the system. The IDS showed high detection rates for both normal and abnormal behavior when evaluated in a testbed using real 1553 hardware, as well as a very fast and accurate training process using logs from a real system. The RT authentication module managed to authenticate RTs with +0.99 precision and +0.98 recall; and detect illegitimate component (or a legitimate component that impersonates other components) with +0.98 precision and +0.99 recall. The sequence-based anomaly detection module managed to perfectly detect both normal and abnormal behavior. Moreover, the sequencebased anomaly detection module managed to accurately (i.e., zero false positives) model the normal behavior of a real system in a short period of time (~22 s).

Safety Assessment Process Optimization for Integrated Modular Avionics

In order to evaluate the safety impacts introduced by the additional interactions between the software partition and the integrated modular avionics platform, an optimized safety assessment process is proposed to address the software partition specific failure mode, quantitative failure rate budget allocation, software reliability verification, and feedback to higher level safety assessment. With a case study based on an airborne datalink system, the optimized safety assessment process is discussed in detail, including the specific failure condition and corresponding preventive/corrective actions, the allocation and verification of software partition failure rate, as well as the feedback channel of these partition software failure rate to item/function failure mode and effect assessment. A reliability framework of partition software is also presented to support the reliability verification of partition software. The methodology is applicable to other IMA-based avionics system.

Automated Requirements and Traceability Generation for a Distributed Avionics Platform

<div class="section abstract"><div class="htmlview paragraph">The development and qualification of distributed and highly safety-critical avionics systems implicate high efforts and risks. The resulting costs usually limit implementations like fly-by-wire systems to the military or commercial airliner domains. The aim of previous and ongoing research at the Institute of Aircraft Systems at University of Stuttgart is the reduction of these costs and therefore open up their benefits, inter alia, to general aviation, remotely piloted or unmanned aircraft. An approach for an efficient development is the application of a platform based development which supports the reuse of software and hardware components. The Flexible Platform adopts this approach. It is accompanied by a tool suite which automates the design and parameter instantiation, documentation generation and the generation of verification artifacts for a platform instance. This paper presents the approach for the requirement document generation compliant to ARP4754A and DO-178C. It is based on configurable requirement classes. In addition, relation classes build the base for the generation of a bidirectional traceability. The implemented system and high-level software requirement classes for the platform signal communication as well as their instantiation with the tool suite were validated with a representative platform instance model for a fly-by-wire system.</div></div>

An Open Source Domain-Specific Avionics System Architecture Model for the Design Phase and Self-Organizing Avionics

<div class="section abstract"><div class="htmlview paragraph">State-of-the-art avionics systems are standardized, e.g. the computing system of the flying vehicle is composed of pre-defined and pre-qualified modules of a standardized avionics platform. Integrated Modular Avionics (IMA) is the most popular representative, but not the only one. Two challenges of standardized avionics platform are system design and configuration. Since the high numbers of functions, modules, and constraints for modern air vehicles, bringing up the optimal system architecture is a difficult job if carried out manually. The subsequent process of creating millions of configuration parameters is time consuming and error prone. Both issues are similar and are, in general, processable by algorithms. Algorithms proved to provide significant support for current system design issues and might be mandatory in future, when avionics become self-organizing and the design and configuration are derived by the platform itself. Automated design already proved its advantages and self-organizing platforms started to be in development. Having the right and rigid data format for this purpose is mandatory. A suitable data format must hold all requirements necessary to proof the validity of the avionics architecture and take reliable organization decisions. It must be independent of technologies, in terms of hardware, software, and configuration. It must have a structure simple enough to be used in qualified embedded systems. Existing modeling approaches, e.g. AADL, have different purposes as detailed system design, dynamic simulations, virtual qualification, and lack especially rigidity and simplicity. The Open Avionics Architecture Model (OAAM) is a domain-specific model representing avionics system’s architectures designed to be used offline or online in the automated organization of avionics systems. It was implemented using the EMOF modeling standard and the Eclipse Modeling Framework (EMF). It is available as open source. This article explains the structure and the purpose of OAAM.</div></div>

Transmission Performance of Plastic Optical Fibers Designed for Avionics Platforms

Plastic optical fibers (POFs) have been proposed and implemented in the avionics environment lately, and temperature is naturally a big factor that can affect their performance in those platforms. We present an experimental characterization of the transmission properties of POFs comparing the performance of standard fibers with that of fibers designed to sustain high temperatures, such as those on avionics platforms. We tested different step-index 1-mm poly(methyl methacrylate) single-core and multicore fibers. Frequency response, bit error rate (BER), attenuation, and output power distribution were measured for each fiber type at room temperature. In addition, BER and fiber attenuation were monitored as a function of temperature, intentionally exceeding the temperature limits to obtain the true temperature ranges and to assess the performance penalty. The same properties were obtained for the overheated fibers and compared to those for nonheated fibers of the same type to reveal permanent performance degradation.

An optimisation approach for pre-runtime scheduling of tasks and communication in an integrated modular avionic system

In modern integrated modular avionic systems, applications share hardware resources on a common avionic platform. Such an architecture necessitates strict requirements on the spatial and temporal partitioning of the system to prevent fault propagation between different aircraft functions. One way to establish a temporal partitioning is through pre-runtime scheduling of the system, which involves creating a schedule for both tasks and a communication network. While avionic systems are growing more and more complex, so is the challenge of scheduling them. The scheduling of the system has an important role in the development of new avionic systems, since functionality is typically added to the system over a period of several years and a scheduling tool is used both to detect if the platform can host the new functionality and, if this is possible, to create a new schedule. For this reason an exact solution strategy for avionics scheduling is preferred over a heuristic one. In this paper we present a mathematical model for an industrially relevant avionic system and present a constraint generation procedure for the scheduling of such systems. We apply our optimisation approach to instances provided by our industrial partner. These instances are of relevance for the development of future avionic systems and contain up to 20,000 tasks to be scheduled. The computational results show that our optimisation approach can be used to create schedules for such instances within a reasonable time.

Fully-Deterministic Execution of IEC-61499 Models for Distributed Avionics Applications

The development of time-critical Distributed Avionics Applications (DAAs) pushes beyond the limit of existing modeling methodologies to design dependable systems. Aerospace and industrial automation entail high-integrity applications where execution time is essential for dependability. This tempts us to use modeling technologies from one domain in another. The challenge is to demonstrate that they can be effectively used across domains whilst assuring temporally dependable applications. This paper shows that an IEC61499-modeled DAA can satisfy temporal dependability requirements as to end-to-end flow latency when it is properly scheduled and realized in a fully deterministic avionics platform that entails Integrated Modular Avionics (IMA) computation along with Time-Triggered Protocol (TTP) communication. Outcomes from the execution design of an IEC61499-based DAA model for an IMA-TTP platform are used to check runtime correctness through DAA control stability. IEC 61499 is a modeling standard for industrial automation, and it is meant to facilitate distribution and reconfiguration of applications. The DAA case study is a Distributed Fluid Control System (DFCS) for the Airbus-A380 fuel system. Latency analysis results from timing metrics as well as closed-loop control simulation results are presented. Experimental outcomes suggest that an IEC61499-based DFCS model can achieve desired runtime latency for temporal dependability when executed in an IMA-TTP platform. Concluding remarks and future research direction are also discussed.

Enhanced Performance Capability in a Dual Redundant Avionics Platform – Fault Tolerant Scheduling with Comparative Evaluation

For mission critical applications like Avionics, dependability is to avoid consequences of catastrophic results. Traditionally fault tolerance is implemented using hardware redundancy, the higher the redundancy, greater the cost and possibilities of more failures occurring. In this paper, an adaptive fault tolerant scheduling mechanism developed earlier with augmented performance capability and online fault recovery for a dual redundant system has been extended for an avionics mission system. An algorithm has been developed, simulated and evaluated on the practical case study vis –a- vis a traditional dual redundant system. This paper also roposes an extension of earlier scheme to schedule arrival of either/and critical and non -critical aperiodic tasks. The augmented scheme helps to achieve full functionality when no fault occurs, a fail safe mechanism for a single fault and performance metrics highlights the better computational performance. It elucidates that the use of this adaptive model leverages better in terms of enhanced performance and throughput compared to the existing dual redundant systems.

DRE system performance optimization with the SMACK cache efficiency metric

System performance improvements are critical for the resource-limited environment of multiple integrated applications executing inside a single distributed real-time and embedded (DRE) system, such as integrated avionics platform or vehtronics systems. While processor caches can effectively reduce execution time there are several factors, such as cache size, system data sharing, and task execution schedule, which make it hard to quantify, predict, and optimize the cache usage of a DRE system. This article presents SMACK, a novel heuristic for estimating the hardware cache usage of a DRE system, and describes a method of varying the runtime behavior of DRE system software without (1) requiring extensive safety recertification or (2) violating the real-time scheduling deadlines. By using SMACK as a maximization target, we were able to reduce integrated DRE system execution time by an average of 2.4% and a maximum of 4.34%.

Design of a hybrid switching architecture for avionic WDM platforms

A novel hybrid switching architecture using optical circuit switching for intra-subnet communication and fiber channel (FC) for inter-subnet communication is proposed. The proposed scheme utilizes small-size arrayed waveguide grating routers (AWGRs) and legacy FC switches to construct the large-scale avionic network, thus has the potential of the lower latency, the satisfactory network bandwidth and the lower power consumption. The simulation results verify that the proposed architecture outperforms FC switched architecture in terms of real time performance and power consumption.

Evolution of the Space Shuttle Primary Avionics Software and Avionics for Shuttle Derived Launch Vehicles

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA s Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a long pole in new development efforts. The and for the Space Shuttle was primarily developed in the 70 s and considered state of the art for that time. As one may argue that the existing and flight may be too outdated to the new SDLV effort, this is a fallacy if they can be evolved over time into a avionics platform. The technology may be outdated, but the concepts and flight algorithms are not. The reuse of existing and also allows for the reuse of development, verification, and operations facilities. The keyword is evolve in that these assets can the fast development of such a vehicle, but then be gradually evolved over time towards more modern platforms as budget and schedule permits. The gold of the flight is the control loop algorithms of the vehicle. This is the Guidance, Navigation, and Control (GNC) algorithms. This is typically the most expensive to develop, test, and verify. Thus, the approach is to preserve the flight software, while first evolving the supporting (such as Command and Data Handling, Caution and Warning, Telemetry, etc.). This can be accomplished by gradually removing the support software from the legacy flight leaving only the algorithms. The support software could be re-developed for modern platforms, while leaving the algorithms to execute on technology compatible with the legacy system. It is also possible to package the algorithms into an emulated version of the original computer (via Field Programmable Gate Arrays or FPGAs), thus becoming a GNC on a Chip solution where it could live forever to be embedded in modern platforms.

Design considerations for systems hosted on integrated modular avionics

System architects are accustomed to developing systems hosted in federated environments that allow for developmental independence. However, the system boundaries are different when systems are hosted in an Integrated Modular Avionics (IMA) platform. The boundaries lie within shared resources, and thus lead to greater dependencies between systems. This drives new design considerations for system architects. The natural tendency is to leverage traditional federated design concepts when building systems for IM1A environments, but this can lead to inefficient use of system resources, and a lack of preparedness for the inevitable change that will occur within the integrated set of systems. NMA has become a standard in the civil and military aviation industries, so it is important to understand these new design considerations. The question addressed by this paper is "What unique design considerations are there for systems hosted on an IMA platform ?" All of the considerations can be attributed to three main drivers present in the IMA environment: * 1) optimization of system resources across the integrated set of hosted systems, * 2) change containment when hosted systems change, and * 3) change containment when the NMA platform elements change (technology insertion). These three factors impact the traditional developmental independence between systems since it requires the architect to consider their system's role within the integrated set of systems. They must now consider how they will tolerate changes that are out of their control, such as changes to other hosted systems or the IMA platform that affect the shared resource performance. They must now consider how they contribute to the efficient use of system resources as part of the greater system-wide optimization strategy. If these factors are not addressed, then it can lead to wasted system resources, increased development costs, and high costs-of-change. Therefore the incentive to ensure that these new design considerations are addressed lies with both the system integrator who owns the integrated set of systems and the architect of each hosted system. This is based upon the authors' experience in developing 11%A systems at GE Aviation. GE Aviation has developed open system 11%A architectures for commercial aircraft (Boeing 787 Dreamliner), as well as military aircraft (Boeing C-130) combat aircraft, and Boeing KC-767 Tanker).

Modelling Real-Time Behaviour of Soft Computations within Integrated Avionics Systems

This paper attempts to model soft real-time avionics computations with a view to their integration into an Integrated Modular Avionics platform. Soft computations are defined here as those computations which have probabilistic, and often long, computation times. The paper first summarises the requirements for soft computations for several avionics application areas. An existing worst-case framework for the development of end-to-end avionics systems is referred to. Finally a probabilistic version of the framework is introduced.

A class of rate-based real-time scheduling algorithms

This paper investigates a class of rate-based real-time scheduling algorithms based on the idea of general processor sharing (GPS). We extend the GPS framework of Parekh and Gallager (1993) for periodic and sporadic process scheduling and show the optimality of GPS-based scheduling. In particular, we propose the earliest-completion-time GPS (EGPS) scheduling algorithm to simulate the GPS algorithm with much lower run-time overheads. The schedulability of each process is enforced by a guaranteed CPU service rate, independent of the demands of other processes. We provide a theoretical foundation to assign proper CPU service rates to processes to satisfy their individual stringent response time requirements. We also propose a GPS-based scheduling mechanism for jitter control. Finally, the performance of the proposed algorithms is studied using a generic avionics platform example and simulation experiments on jitter control and mixed soft and hard real-time process scheduling.

A cost effective critical space systems design approach

NASA-ISC requires avionics platforms capable of serving a wide range of applications in a cost-effective manner. In part, making the avionics platform cost effective means adhering to open standards and supporting the integration of COTS products with custom products. Inherently, operation in space requires low power, mass, and volume while retaining high performance, reconfigurability, scalability, and upgradability. The Universal Mini-Controller (UMC) project is based on a modified PC/104-Plus architecture while maintaining full compatibility with standard COTS PC/104 products. The architecture consists of a library of stackable building block modules, which can be mixed and matched to meet a specific application. A set of NASA developed core building blocks, (e.g. processor card, analog input/output card, high level analog card, and a Mil-Std-1553 card) were constructed to meet critical functions and unique interfaces.