References of "Havet, Lionel"
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See detailA Model-Driven Co-Design Framework for Fusing Control and Scheduling Viewpoints
Sundharam, Sakthivel Manikandan UL; Navet, Nicolas UL; Altmeyer, Sebastian et al

in Sensors (2018), 18(2), 628

Model-Driven Engineering (MDE) is widely applied in the industry to develop new software functions and integrate them into the existing run-time environment of a Cyber-Physical System (CPS). The design of ... [more ▼]

Model-Driven Engineering (MDE) is widely applied in the industry to develop new software functions and integrate them into the existing run-time environment of a Cyber-Physical System (CPS). The design of a software component involves designers from various viewpoints such as control theory, software engineering, safety, etc. In practice, while a designer from one discipline focuses on the core aspects of his field (for instance, a control engineer concentrates on designing a stable controller), he neglects or considers less importantly the other engineering aspects (for instance, real-time software engineering or energy efficiency). This may cause some of the functional and non-functional requirements not to be met satisfactorily. In this work, we present a co-design framework based on timing tolerance contract to address such design gaps between control and real-time software engineering. The framework consists of three steps: controller design, verified by jitter margin analysis along with co-simulation, software design verified by a novel schedulability analysis, and the run-time verification by monitoring the execution of the models on target. This framework builds on CPAL (Cyber-Physical Action Language), an MDE design environment based on model-interpretation, which enforces a timing-realistic behavior in simulation through timing and scheduling annotations. The application of our framework is exemplified in the design of an automotive cruise control system. [less ▲]

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See detailA Model-Based Development Environment for Rapid-Prototyping of Latency-Sensitive Automotive Control Software
Sundharam, Sakthivel Manikandan UL; Havet, Lionel; Altmeyer, Sebastian et al

in Proceedings of 6th Intentional Symposium on Embedded computing & system Design (ISED 2016) (2016, December 15)

The innovation in the field of automotive embedded systems has been increasingly relying on software-implemented functions. The control laws of these functions typically assume deterministic sampling ... [more ▼]

The innovation in the field of automotive embedded systems has been increasingly relying on software-implemented functions. The control laws of these functions typically assume deterministic sampling rates and constant delays from input to output. However, on the target processors, the execution times of the software will depend on many factors such as the amount of interferences from other tasks, resulting in varying delays from sensing to actuating. Three approaches supported by tools, namely TrueTime, T-Res, and SimEvents, have been developed to facilitate the evaluation of how timing latencies affect control performance. However, these approaches support the simulation of control algorithms, but not their actual implementation. In this paper, we present a model interpretation engine running in a co-simulation environment to study control performances while considering the run-time delays in to account. Introspection features natively available facilitate the implementation of self-adaptive and fault-tolerance strategies to mitigate and compensate the run-time latencies. A DC servo controller is used as a supporting example to illustrate our approach. Experiments on controller tasks with injected delays show that our approach is on par with the existing techniques with respect to simulation. We then discuss the main benefits of our development approach that are the support for rapid-prototyping and the re-use of the simulation model at run-time, resulting in productivity and quality gains. [less ▲]

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See detailLean Model-Driven Development through Model-Interpretation: the CPAL design flow
Navet, Nicolas UL; Fejoz, Loïc; Havet, Lionel et al

Scientific Conference (2016, January 27)

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model ... [more ▼]

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model-interpretation and providing the language abstractions needed to argue about the timing correctness on a high-level. The MDD flow is built around a language called Cyber-Physical Action Language (CPAL). CPAL serves to describe both the functional behaviour of activities (i.e., the code of the function itself) as well as the functional architecture of the system (i.e., the set of functions, how they are activated, and the data flows among the functions). CPAL is meant to support two use-cases. Firstly, CPAL is a development and design space exploration environment for CPS with main features being the formal description, the editing, graphical representation and simulation of CPS models. Secondly, CPAL is a real-time execution platform. The vision behind CPAL is that a model is executed and verified in simulation mode on a workstation and the same model can be later run on an embedded board with a timing-equivalent run-time time behaviour. [less ▲]

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See detailLean Model-Driven Development through Model-Interpretation: the CPAL design flow
Navet, Nicolas UL; Fejoz, Loïc; Havet, Lionel et al

Report (2015)

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model ... [more ▼]

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model-interpretation and providing the language abstractions needed to argue about the timing correctness on a high-level. The MDD flow is built around a language called Cyber-Physical Action Language (CPAL). CPAL serves to describe both the functional behaviour of activities (i.e., the code of the function itself) as well as the functional architecture of the system (i.e., the set of functions, how they are activated, and the data flows among the functions). CPAL is meant to support two use-cases. Firstly, CPAL is a development and design space exploration environment for CPS with main features being the formal description, the editing, graphical representation and simulation of CPS models. Secondly, CPAL is a real-time execution platform. The vision behind CPAL is that a model is executed and verified in simulation mode on a workstation and the same model can be later run on an embedded board with a timing-equivalent run-time time behaviour. [less ▲]

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See detailCombining static priority and weighted round-robin like packet scheduling in AFDX for incremental certification and mixed-criticality support
Boyer, Marc; Navet, Nicolas UL; Fumey, Marc et al

in Proceedings of the 5th European Conference for Aeronautics and Space Sciences (EUCASS) (2013, July 01)

The Deficit Round Robin (DRR) policy can be used at the outgoing ports of communication switches to schedule distinct classes of frames, providing each class with a guaranteed share of the network ... [more ▼]

The Deficit Round Robin (DRR) policy can be used at the outgoing ports of communication switches to schedule distinct classes of frames, providing each class with a guaranteed share of the network bandwidth. The independence between traffic classes helps to improve the incremental design process, incremental certification and scheduling flows with mixed criticalities. DRR leads however to a less efficient use of hardware resources, this is why we also envisage the combined use of DRR and Static Priority (SP). We then provide a first quantitative assessment on a realistic case-study about the use of DRR, possibly combined with SP, in avionics networking and shed some light on its range of applicability. [less ▲]

Detailed reference viewed: 56 (3 UL)