Quo vadis real time ethernet

Real time Ethernet (RTE) protocol suites are commonly operated within an exclusively allocated Ethernet based network that is used to exchange data for a distributed real time application. In practice, RTE protocol stack implementations interlace the maintenance of their data objects on the (standardised and loosely coupled) application layer with the task of traffic fitting. The latter includes the egress and ingress of application data over the underlying layers but also the coordination (scheduling) of the same. The set of time sensitive networking (TSN) IEEE standards is an addendum to common Ethernet (IEEE 802.3*). It has the aim to provide technologies to implement deterministic Ethernet networks. In factory automation RTE, an ongoing establishment of such technologies is observed. They lay the ground for various possibilities to shift the mechanisms for scheduling data transmissions towards networking juncture elements, e.g. Ethernet switch. This work intends to fabricate a stronger separation between the application layer and the tasks concerning traffic fitting. A demonstration setup is developed. It consists of an Ethernet switch (partly TSN capable), two programmable logic controllers (PLCs) and one input/output (I/O) device. Simultaneous operation of two unsimilar RTE protocol suites within the same network is shown. Possible optimisations applied to RTE application components, which target a higher level of determinism, are presented. Measurements underpin the chosen optimisations

Mixed criticality communication within an unmanned delivery rotorcraft

Stand-alone functions additional to a UAV flight-controller, such as safety-relevant flight-path monitoring or payload-monitoring and control, may be SORA-required or advised for specific flight paths of delivery-drones. These functions, articulated as discrete electronic components either internal or external to the main fuselage, can be networked with other on-board electronics systems. Such an integration requires respecting the integrity levels of each component on the network both in terms of function and in terms of power-supply. In this body of work we detail an intra-component communication system for small autonomous and semi-autonomous unmanned aerial vehicles (UAVs.) We discuss the context and the (conservative) design decisions before detailing the hardware and software interfaces and reporting on a first implementation. We finish by drawing conclusions and proposing future work

Towards securing hard real-time networked embedded devices and systems : a cBPF implementation for an FPGA

In this body of work we describe preliminary work implementing a Berkely Packet Filter, in its original conception, in an FPGA. The purpose is packet filtering and ingress traffic shaping in security-relevant applications in distributed embedded nodes. We specifically target PROFINET nodes in hard real-time applications where network security is an open issue. We describe the motivation, implementation and verification including performance characteristics. We conclude that such a filter can be used to not only for protection against simple denial-of-service attacks but also for ingress protocol management and potentially for the implementation of system-wide security policies

HORUS : High Operational Reliability for Unmanned Systems

In an effort to increase Unmanned Aerial Vehicles (UAV) mission safety and reliability, this paper introduces the HORUS prototype. HORUS is a small hardware device that allows UAVs to be flown with two Commercial Off The Shelf (COTS) Flight Control Units (FCU) instead of a single one traditionally. The HORUS device offers the possibility to manually switch from one FCU to the other but also to switch autonomously if the UAV gets out of the allowed geographic boundaries or out of its defined flight envelope. Although envelope protection or geofencing features are commonly available on COTS FCUs, they are generally not robust to sensor or FCU failures. But, as a result of its design, which has been developed following manned aviation safety process guidelines, the HORUS device offers high reliability and integrity. In this context, the main objective of this paper is to introduce the HORUS concept, to describe the software and hardware architectures and to demonstrate its functionality by showing some flight test results