Section: New Results

Pervasive Computing

Participants : Laurent Ciarletta [contact] , Olivier Festor, Ye-Qiong Song, Yannick Presse, Emmanuel Nataf.

Vincent Chevrier, Thomas Navarrete Gutierrez and Julien Vaubourg (MAIA team) did contribute to part of this activity.

In Pervasive or Ubiquitous Computing, a growing number of communicating/computing devices are collaborating to provide users with enhanced and ubiquitous services in a seamless way. In a related field, Cyber Physical Systems also are technological systems that have to be considered within a physical world and its contraints. They are complex systems where several inter-related phenomena have to be considered. In order to be studied, modeled and evaluated, we propose the use of co-simulation and multimodeling.

Pervasive Computing is about interconnected and situated computing resources providing us(ers) with contextual services. These systems, embedded in the fabric of our daily lives, are complex: numerous interconnected and heterogeneous entities are exhibiting a global behavior impossible to forecast by merely observing individual properties. Firstly, users physical interactions and behaviors have to be considered. They are influenced and influence the environment. Secondly, the potential multiplicity and heterogeneity of devices, services, communication protocols, and the constant mobility and reorganization also need to be addressed. Our research on this field is going towards both closing the loop between humans and systems, physical and computing systems, and taming the complexity, using multi-modeling (to combine the best of each domain specific model) and co-simulation (to design, develop and evaluate) as part of a global conceptual and practical toolbox. We're applying this work on UAvs, dynamic networks (adhoc, mesh, P2P, wireless sensors and actuators), energy-constrained / location aware services, smart grids etc.

Such systems can be seen as complex and are present everywhere in our environment: internet, electricity distribution networks, transport networks. This systems have as characteristics: a large number of autonomous entities, dynamic structures, different time and space scales and emergent phenomena.

Application domains such as Smart Spaces, Smart Cities, Smart Trasportation Systems and Smart Grid makes us sometimes use Smart* or SmartX as a generic word. Madynes is focusing on the networking aspects of such systems and on the tools to develop and assess them. We cooperate with other teams and most notably the Maia team to be able to encompass issues and research questions that combine both networking and cognitive aspects.

In 2013 we worked on the following research topics :

• Assessment and evaluation of complex systems. Continuing the work on multi-modeling and co-simulation, we have participated with the MAIA team on the development of an architecture for the control of complex systems based on multi-agent simulation, a CPS co-simulation (next item) and a Smart grid simulation tool (last item), and continue working on the AA4MM framework (Agents and artefacts for Multiple heterogeneous Models).

  A control architecture has been proposed by Tomas Navarrete, based on an “equation-free” approach. We use a multi-agent model to evaluate the global impact of local control actions before applying the most pertinent set of actions. Associated to our architecture, an experimental platform has been developed to confront the basic ideas or the architecture within the context of simulated “free-riding” phenomenon in peer to peer file exchange networks. We have demonstrated that our approach allows to drive the system to a state where most peers share files, despite given initial conditions that are supposed to drive the system to a state where no peer shares. We have also executed experiments with different configurations of the architecture to identify the different means to improve the performance of the architecture.

  This work helped us to identify [13] the key issues related to the usage of the multi-agent paradigm in the context of control of complex systems.

• In Cyper Physical Systems, we have lead the design and implementation of the Aetournos (Airborne Embedded auTonomOUs Robust Network of Objects and Sensors) platform at Loria. The idea of AETOURNOS is to build a platform which can be at the same time a demonstrator of scientific realizations and an evaluation environment for research works of various teams of our laboratory. It is also its own research domain : building a completely autonomous and robust flock of collaborating UAVs.

  In Madynes, we focus on the CPS and their networks and applications. Those systems consist of numerous autonomous elements in sharp interaction which functioning require a tight coupling between software implementations and technical devices. The collective movements of a flock of flying communicating robots / UAVs, evolving in potentially perturbed environment constitute a good example of such a system. Indeed, if we look at the level of each of the elements playing a role into this system, a certain number of challenges and scientific questions can be studied: respect of real-time constraints of calculations for every autonomous UAV and for the communication between the robots, conception of individual, embedded, distributed or global management systems, development of self-adaptative mechanisms, conception of algorithms of collective movement etc... Furthermore, the answers to each of these questions have to finally contribute to the global functioning of the system. Applying co-simulation technique we plan to develop a hybrid "network-aware flocking behavior" / "behavior aware routing protocol". The platform is composed of several high-grade research UAVs (Pelican quadcopters and Firefly hexacopters) and lighter models (AR.Drone quacopters). We have provided a working set of tools : multi-simulation behavior / network / physics and generic software development using ROS (Robot Operating System). The UAVs carry a set of sensor for location awareness, their own computing capabilities and several wireless networks.

  This work is discribed in a position paper where a first implementation of a formation flight is detailed [29] .

• Smart grids and Smart spaces are another application domain. MS4SG (cf. has given us the opportunity to link multi-simulations tools such as HLA (High Level Architecture) and FMI (Functional Mockup Interface) thanks to our AA4MM framework. We've so far successfully applied our solution to the simulation of smart appartment complex and to combining the electrical and networking part of a Smart Grid (first deliverable and first workshop with EDF R&D, Supélec and SIANI were in september 2013). A paper has also been accepted to Simutools 2014. In 2014, we will continue working on the hybrid protocols and on the UAV platform, and apply our co-simulation work to Smart Grids and other Smart* [13] .