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In embedded real-time virtualized systems (ERTVS), the ARINC 653 standard specifies a cyclic scheduling policy to guarantee the real-time performance of tasks in multiple Virtual Machines (VMs) residing on shared hardware. Based on this policy, the Regularity-based Resource Partitioning (RRP) model defines an efficient interface specification to hierarchically partition and assign resource slices among VMs. Although this model has received plenty of attention recently, three major pieces remain missing for applying this model in ERTVS. (1) Embedded systems are more sensitive to resource utilization efficiency since this may drastically affect their deployment cost for including additional cores. Therefore, this paper proposes an optimal and an approximate RRP resource scheduler for multi-core platforms. (2) A resource reconfiguration is required when an embedded system has to switch between operating modes, resulting in the current cyclic schedule being replaced by another pre-configured and verified cyclic schedule. This paper formalizes a new One-Hop Reconfiguration (OHR) problem tailored for mode-switch-capable embedded systems and introduces a corresponding optimal solution. (3) No RRP-based toolset is currently available for embedded systems. This paper thus presents an optimized RRP toolset tailored for embedded systems. Numerous experiments are conducted to evaluate the efficacy of this toolset. [ABSTRACT FROM AUTHOR]

The ARINC 653 operation system is currently widely adopted in the avionics industry, and has become the mainstream architecture in avionics applications because of its strong agility and reliability. Although ARINC 653 can efficiently reduce the weight and energy consumption, it results in a serious development and verification problem for avionics systems. As ARINC 653 is non-open source software and lacks effective support for software testing and debugging, it is of great significance to build a real-time simulation platform for ARINC 653 on general-purpose operating systems, improving the efficiency and effectiveness of system development and implementation. In this paper, a virtual ARINC 653 platform is designed and realized by using real-time simulation technology. The proposed platform is composed of partition management, communication management, and health monitoring management, provides the same operation interfaces as the ARINC 653 system, and allows dynamic debugging of avionics applications without requiring the actual presence of real devices. Experimental results show that the platform not only simulates the functionalities of ARINC 653, but also meets the real-time requirements of avionics applications. [ABSTRACT FROM AUTHOR]

The creation of reliable unmanned aerial vehicles (drones) now is an important task in the science and technology, because such devices can have a lot of use-cases in the digital economy and modern life, so we need to ensure the reliability here. In this article, it is proposed to assemble a quadcopter from low-cost components in order to obtain a hardware prototype and to develop a software solution for the flight controller with high-reliability requirements, which will meet avionics software standards using existing open-source software solutions, and also apply the results as a model for teaching courses “Components of operating systems” and “Software verification”. In the study, we proceed to analyse the structure of quadcopters and flight controllers for them, represent a self-assembly solution. We describe Ardupilot as open-source software for unmanned aerial vehicles, the appropriate APM controller and methods of PID control. Today's avionics standard of reliable software for flight controllers is a real-time partitioning operating system that is capable of responding to events from devices with an expected speed, as well as sharing processor time and memory between isolated partitions. A good example of such OS is the open-source POK (Partitioned Operating Kernel). In the repository, it contains an example design of a system for the quadcopters using AADL language for modeling its hardware and software. We apply such a technique with Model-driven engineering to a demo system that runs on real hardware and contains a flight management process with PID control as a partitioned process. Using a partitioned OS brings the reliability of flight system software to the next level. And to increase the level of control logic correctness we propose to use formal verification methods and provide examples of verifiable properties at the level of code using the deductive approach as well as at the level of the cyber-physical system using Differential dynamic logic to prove the stability.

Modern airliners such as Airbus A320, Boeing 787, and Russian MS-21 use so called Integrated Modular Avionics (IMA) architecture for airborne systems. This architecture is based on interconnection of devices and on-board computers by means of uniform real-time network. It allows significant reduction of cable usage, thus leading to reducing of takeoff weight of and airplane. IMA separates functions of collecting information (sensors), action (actuators), and avionics logic implemented by applied avionics software in on-board computers. International standard ARINC 653 defines constraints on the underlying real-time operation system and programming interfaces between operating system and associated applications. The standard regulates space and time partitioning of applied IMA-related tasks. Most existing operating systems with ARINC 653 support are commercial and proprietary software. In this paper, we present JetOS, an open source real-time operating system with complete support of ARINC 653 part 1 rev 3. JetOS originates from the open source project POK, created by French researchers. At that time POK was the only one open source OS with at least partial support for ARINC 653. Despite this, POK was not feasible for practical usage: POK failed to meet a number of fundamental requirements and was executable in emulator only. During JetOS development POK code was significantly redesigned. The paper discusses disadvantages of POK and shows how we solved those problems and what changes we have made in POK kernel and individual subsystems. In particular we fully rewrote real-time scheduler, network stack and memory management. Also we have added some new features to the OS. One of the most important features is system partitions. System partition is a specialized application with extended capabilities, such as access to hardware (network card, PCI controller etc.) Introduction of system partitions allowed us moving large subsystems out of the kernel and limiting the kernel to the minimal functionality: context switching, scheduling and message pass. In particular, we have moved network subsystem to system partition. This moving reduces kernel size and potentially reduces probability on having bug in kernel and simplifies verification process.

JetOS is a prospective onboard real-time operating system (RTOS). Nowadays GosNIIAS develops JetOS in the scope of the research and development project. One of the most important tasks during JetOS development is to create the DO-178C certification kit, which will allow JetOS to be used for development and modification of avionics for civil aircraft. Today there is no operating system certified in accordance with DO-178C in Russia, therefore the JetOS creation is the matter of current importance. Using DO-178C requires the developer to have very strict development processes. The arrangement of processes that satisfy the DO-178C requirements is a very responsible and demanding task because of high expectations in the fields of safety and security. JetOS is being developed primarily for onboard equipment based on the integrated modular avionics (IMA). One of the key features of IMA is the ability to execute several functional applications on one target onboard module. The obvious consequence of this feature is a necessity to have a time and resource partitioning of applications. In avionics field application partition along with a host of other features is defined in ARINC 653 international standard, so its support is the significant requirement for JetOS. ARINC 653 defines application programming interface (API) and modes of operation for onboard functional software. JetOS supports the up-to-date version of ARINC 653 (2015) with supplementary services. JetOS also supports the safety-critical graphical library - OpenGL SC; the special implementation of the OpenGL SC library is being developed along with JetOS itself. OpenGL SC services are used to draw two-dimensional and three-dimensional pictures by onboard functional software. JetOS is a certifiable modular cyber-safe real-time operating system, which is designed in order to support several hardware architectures and to be easily adopted for different hardware boards. The scope of the JetOS project also includes creation of the tools necessary for functional software development, especially aircraft systems.

Recently, avionics systems have evolved into a time and space partitioning (TSP)-based integrated modular avionics (IMA) structure for integration into a single system from a variety of existing independently configured federated systems. The TSP-based IMA architecture is suitable for solving size, weight, and power problems in avionics systems. Partitioning real-time operating systems (RTOSs) to support TSP-based IMA have been researched, and the international aviation industry has established the ARINC 653 standard for a partitioning RTOS. The ARINC 653 standard has defined the health monitoring (HM) function for debugging. However, the HM of the ARINC 653 standard does not support monitoring and debugging functions, such as snapshot, cycle, and, redundancy monitor, which makes the system development hard. To this end, the purpose of this paper is to introduce a monitoring framework that supports high reliability and stability for RTOS and application software based on TSP structure used in avionics systems. The proposed monitoring framework is designed for Qplus-AIR, an RTOS based on the TSP structure that conforms to the ARINC 653 for aircraft systems. It is also applicable to other RTOSs based on TSP structure that does not conform to ARINC 653. It supports monitoring functions, such as snapshot, trigger, and cycle as well as various debugging functions. It also supports debugging and monitoring operations under the redundancy of avionics systems, and minimizes the intrusive effect, which is a disadvantage of the software-based debugging approach. These functionalities enable avionics system developers to monitor and measure the performance of TSP structure-based RTOS and application software in flight control system for unmanned aerial vehicles. Our evaluation results show that the proposed monitoring framework is suitable for monitoring and debugging of RTOS and application software based on TSP structure.

Partitioning operating systems (POSs) have been widely applied in safety-critical domains from aerospace to automotive. In order to improve the safety and the certification process of POSs, the ARINC 653 standard has been developed and complied with by the mainstream POSs. Rigorous formalization of ARINC 653 can reveal hidden errors in this standard and provide a necessary foundation for formal verification of POSs and ARINC 653 applications. For the purpose of reusability and efficiency, a novel methodology by integrating ontology and refinement is proposed to formally specify and analyze POSs in this paper. An ontology of POSs is developed as an intermediate model between informal descriptions of ARINC 653 and the formal specification in Event-B. A semiautomatic translation from the ontology and ARINC 653 into Event-B is implemented, which leads to a complete Event-B specification for ARINC 653 compliant POSs. During the formal analysis, six hidden errors in ARINC 653 have been discovered and fixed in the Event-B specification. We also validate the existence of these errors in two open-source POSs, i.e., XtratuM and POK. By introducing the ontology, the degree of automatic verification of the Event-B specification reaches a higher level. [ABSTRACT FROM PUBLISHER]

ABSTRACT Most current generation avionics systems are based on a federated architecture, where an electronic device runs a single software module or application that collaborates with other devices through a network. This architecture makes the software development process very simple, but the hardware system becomes very complicated and it is difficult to resolve issues of size, weight, and power efficiently. An integrated architecture can address the size, weight, and power issues and provide better software reusability, testability, and reliability by means of partitioning. Partitioning provides a framework that can transparently integrate several real-time applications on the same computing device, allowing the isolation of the execution environment in terms of resources and faults. Several studies on partitioning software platforms have been reported; however, to the best of our knowledge, extensive comparison and analysis of design and implementation alternatives have not been conducted owing to the extreme complexity of their implementation and measurement. In this paper, we present three design alternatives for partitioning at the user, kernel, and virtual machine monitor levels, which are compared quantitatively. In particular, we target the worldwide standard software platform for avionics systems, that is, Aeronautical Radio, Incorporated Specification 653 (ARINC 653). Overall, our study provides valuable design references and demonstrates the characteristics of design alternatives. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Main features of Baget 2.0 and Baget 3.0 Russian real-time operating systems (RTOSs) are discussed. Their similarities and differences are examined. Ways of further development of RTOS Baget are considered. [ABSTRACT FROM AUTHOR]