Biblio
Cyber-physical systems (CPS) research leverages the expertise of researchers from multiple domains to engineer complex systems of interacting physical and computational components. An approach called co-simulation is often used in CPS conceptual design to integrate the specialized tools and simulators from each of these domains into a joint simulation for the evaluation of design decisions. Many co-simulation platforms are being developed to expedite CPS conceptualization and realization, but most use intrusive modeling and communication libraries that require researchers to either abandon their existing models or spend considerable effort to integrate them into the platform. A significant number of these co-simulation platforms use the High Level Architecture (HLA) standard that provides a rich set of services to facilitate distributed simulation. This paper introduces a simple gateway that can be readily implemented without co-simulation expertise to adapt existing models and research infrastructure for use in HLA. An open-source implementation of the gateway has been developed for the National Institute of Standards and Technology (NIST) co-simulation platform called the Universal CPS Environment for Federation (UCEF).
With the increasing interest in studying Automated Driving System (ADS)-equipped vehicles through simulation, there is a growing need for comprehensive and agile middleware to provide novel Virtual Analysis (VA) functions of ADS-equipped vehicles towards enabling a reliable representation for pre-deployment test. The National Institute of Standards and Technology (NIST) Universal Cyber-physical systems Environment for Federation (UCEF) is such a VA environment. It provides Application Programming Interfaces (APIs) capable of ensuring synchronized interactions across multiple simulation platforms such as LabVIEW, OMNeT++, Ricardo IGNITE, and Internet of Things (IoT) platforms. UCEF can aid engineers and researchers in understanding the impact of different constraints associated with complex cyber-physical systems (CPS). In this work UCEF is used to produce a simulated Operational Domain Design (ODD) for ADS-equipped vehicles where control (drive cycle/speed pattern), sensing (obstacle detection, traffic signs and lights), and threats (unusual signals, hacked sources) are represented as UCEF federates to simulate a drive cycle and to feed it to vehicle dynamics simulators (e.g. OpenModelica or Ricardo IGNITE) through the Functional Mock-up Interface (FMI). In this way we can subject the vehicle to a wide range of scenarios, collect data on the resulting interactions, and analyze those interactions using metrics to understand trustworthiness impact. Trustworthiness is defined here as in the NIST Framework for Cyber-Physical Systems, and is comprised of system reliability, resiliency, safety, security, and privacy. The goal of this work is to provide an example of an experimental design strategy using Fractional Factorial Design for statistically assessing the most important safety metrics in ADS-equipped vehicles.