WIreless network supported by a Snowball SDK Access Point (static ad-hoc server configuration). â¡ WSN with 3 UDOO platforms connected through the AP.
Design flow for the rigorous development of networked embedded systems Alexios Lekidis Verimag, Universit´ e Grenoble Alpes
10 December 2015 Committee: Ahmed Lbath Roman Obermaisser Roberto Passerone Smail Niar Marius Bozga Saddek Bensalem
Alexios Lekidis
Professeur, Universit´ e Joseph Fourier Grenoble, President du jury Professeur, Universit¨ at Siegen, Rapporteur Professeur, University of Trento, Rapporteur Professeur, Universit´ e de Valenciennes, Examinateur Ing´ enieur de recherche, CNRS, Directeur de th` ese Professeur, Universit´ e Joseph Fourier Grenoble, Co-Directeur de th` ese
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Networked embedded systems
Exponential growth in the current use of embedded devices due to: Compact size Low-cost Low-power consumption Portability Ability of monitoring the physical environment I Data exchange capabilities through wired or wireless networks I I I I I
Application areas include: Health-care, transportation, agriculture, environmental monitoring, security systems, industrial process control, factory and building automation and control, high-energy physics
Alexios Lekidis
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Networked embedded systems: Design challenges A collection of embedded devices that are interconnected by a wired/wireless network
Embedded Device
Embedded Device
Embedded Device
Embedded Device
Network
Alexios Lekidis
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Networked embedded systems: Design challenges A collection of embedded devices that are interconnected by a wired/wireless network
Embedded Device
Embedded Device
Embedded Device
Embedded Device
Network
Considerable complexity during system design Heterogeneity in: I Device functionalities, sensors/actuators, processing units etc I Operating systems, drivers I Network protocols I Communication mechanisms for data exchange Limited resources Functional and extra-functional requirements Alexios Lekidis
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Networked embedded systems: Design challenges Heterogeneity in network protocols
Selection based on system specifications from: Wired and wireless Event- and time-triggered technologies Affects application perfomance and functionality Alexios Lekidis
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Networked embedded systems: Design challenges Resource constraints Scarce hardware resources: Processing power, available memory, network bandwidth, battery lifetime I Resources should not reach a critical state
Functional and extra-functional requirements 1. Functional: Correctness, robustness, deadlock-freedom 2. Extra-functional enforce bounds in: I QoS: Communication and data processing latencies I Energy consumption and maintaining the desired system temperature levels
Both types of requirements are equally important for system development
Alexios Lekidis
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Existing development methods
Several methods for the development of embedded systems Extension to networked embedded systems requires:
I Knowledge of network stack protocols I Handling more complex Interactions with the device drivers No guarantee of correct functionality
Alexios Lekidis
makeSense project (www.project-makesense.eu)
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Thesis contribution
A model-based approach for building functional networked embedded systems Early-stage simulation and testing, performance evaluation as well as verification of system requirements Progressive system implementation through novel developed tools that automate system development Development of components that describe faithfully the system behavior and functionality in a higher abstraction level Experiments on relevant case-studies for several application domains: I I I I
Alexios Lekidis
Automotive Industrial automation Wireless Sensor Network (WSN) systems Internet of Things (IoT) systems
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•Design flow for Networked Embedded Systems
Outline Motivation •Design flow for Networked Embedded Systems •Background: The BIP Framework •Overview of the proposed flow •Insight on the flow phases 4 4 4 4
Application modeling Code generation System modeling Performance evaluation
•Application and experiments •Overview •Case study 1: Clock synchronization in a multimedia WSN Application •Case study 2: Smart heating IoT application •Conclusion
Alexios Lekidis
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•Design flow for Networked Embedded Systems
•Background: The BIP Framework
The BIP Framework A formal framework for the hierarchical construction of heterogeneous real-time systems:
Alexios Lekidis
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•Design flow for Networked Embedded Systems
•Background: The BIP Framework
The BIP Framework A formal framework for the hierarchical construction of heterogeneous real-time systems: if (nodeNum ≤ 1) then eval:=1 else eval:=0 sndPacket nodeNum
beginT
beginT nodeNum:=nodeNum+1 busy nodeNum:=nodeNum+1 sending [nodeNum ≤ 1] L0
L1
endT nodeNum=nodeNum-‐1
newTrans [nodeNum=0]
s0
busy
s1
backoff=distVal*aUnitBackoffPeriod
6ck [t
