47 research outputs found
Simulation of Mixed Critical In-vehicular Networks
Future automotive applications ranging from advanced driver assistance to
autonomous driving will largely increase demands on in-vehicular networks. Data
flows of high bandwidth or low latency requirements, but in particular many
additional communication relations will introduce a new level of complexity to
the in-car communication system. It is expected that future communication
backbones which interconnect sensors and actuators with ECU in cars will be
built on Ethernet technologies. However, signalling from different application
domains demands for network services of tailored attributes, including
real-time transmission protocols as defined in the TSN Ethernet extensions.
These QoS constraints will increase network complexity even further.
Event-based simulation is a key technology to master the challenges of an
in-car network design. This chapter introduces the domain-specific aspects and
simulation models for in-vehicular networks and presents an overview of the
car-centric network design process. Starting from a domain specific description
language, we cover the corresponding simulation models with their workflows and
apply our approach to a related case study for an in-car network of a premium
car
Application Agreement and Integration Services
Application agreement and integration services are required by distributed, fault-tolerant, safety critical systems to assure required performance. An analysis of distributed and hierarchical agreement strategies are developed against the backdrop of observed agreement failures in fielded systems. The documented work was performed under NASA Task Order NNL10AB32T, Validation And Verification of Safety-Critical Integrated Distributed Systems Area 2. This document is intended to satisfy the requirements for deliverable 5.2.11 under Task 4.2.2.3. This report discusses the challenges of maintaining application agreement and integration services. A literature search is presented that documents previous work in the area of replica determinism. Sources of non-deterministic behavior are identified and examples are presented where system level agreement failed to be achieved. We then explore how TTEthernet services can be extended to supply some interesting application agreement frameworks. This document assumes that the reader is familiar with the TTEthernet protocol. The reader is advised to read the TTEthernet protocol standard [1] before reading this document. This document does not re-iterate the content of the standard
Modeling and Analysis of Mixed Synchronous/Asynchronous Systems
Practical safety-critical distributed systems must integrate safety critical and non-critical data in a common platform. Safety critical systems almost always consist of isochronous components that have synchronous or asynchronous interface with other components. Many of these systems also support a mix of synchronous and asynchronous interfaces. This report presents a study on the modeling and analysis of asynchronous, synchronous, and mixed synchronous/asynchronous systems. We build on the SAE Architecture Analysis and Design Language (AADL) to capture architectures for analysis. We present preliminary work targeted to capture mixed low- and high-criticality data, as well as real-time properties in a common Model of Computation (MoC). An abstract, but representative, test specimen system was created as the system to be modeled
Real-Time Performance of Industrial IoT Communication Technologies: A Review
With the growing need for automation and the ongoing merge of OT and IT,
industrial networks have to transport a high amount of heterogeneous data with
mixed criticality such as control traffic, sensor data, and configuration
messages. Current advances in IT technologies furthermore enable a new set of
automation scenarios under the roof of Industry 4.0 and IIoT where industrial
networks now have to meet new requirements in flexibility and reliability. The
necessary real-time guarantees will place significant demands on the networks.
In this paper, we identify IIoT use cases and infer real-time requirements
along several axes before bridging the gap between real-time network
technologies and the identified scenarios. We review real-time networking
technologies and present peer-reviewed works from the past 5 years for
industrial environments. We investigate how these can be applied to
controllers, systems, and embedded devices. Finally, we discuss open challenges
for real-time communication technologies to enable the identified scenarios.
The review shows academic interest in the field of real-time communication
technologies but also highlights a lack of a fixed set of standards important
for trust in safety and reliability, especially where wireless technologies are
concerned.Comment: IEEE Internet of Things Journal 2023 | Journal article DOI:
10.1109/JIOT.2023.333250
Arquitecturas de hardware para um veículo eléctrico
Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 201