EMN - École des Mines de Nantes

The Constraint team was formed in the 1990s when constraint programming became widely used in industry thanks to companies such as Ilog or Cosytec. After an initial phase of growth in the industrial environment, and more recently in the academic world (CWI, Brown, Melbourne, Montreal), a large number of teams have agreed on the need for convergence with operational research. Considerable work in this direction has been undertaken since the late 90s. Although results have been obtained, it has paradoxically led to the appearance of a large number of niches that cannot be easily exploited by non-specialists in the field. Today, aware of these limitations, the constraint team is focusing on an approach that integrates, in a transparent way, the languages and the different techniques underlying constraint programming. The idea is mainly to develop generic techniques enabling both the integration and unification of the different aspects and new extensions of constraint programming.

We aim to develop the practical application of constraint programming and to make it evolve to meet the needs of industry and/or academia. The three main topics we are already working on are geometric constraints, problems based on graphs and dynamic problems - mission planning, management of refineries. This activity is carried out both at regional level in partnership with local companies (Project RIAM SEISM with Succubus in Nantes, a regional project in the logistics field with the IRCCyN SLP team), and national level with large groups (Bouygues, Dassault, Peugeot, Sagem, Total), or at European level in the frame of the NetWMS (STREP) project on warehouse management..

These projects enable us to contribute to the constraint programming library CHOCO (http://choco.mines-nantes.fr) that we are developing in partnership with Amadeus and Bouygues SA. CHOCO is the flagship product of the team and has a full-time engineer for maintenance and sustainability.

Our goal is to work towards a new generation of constraint programming systems integrating different paradigms of resolution (reformulation of models, constraint learning, filtering, explanations, continuous constraints, meta-heuristics, decomposition, planning, etc.).. We are therefore working on algorithmic aspects, temporal aspects and user interfaces. Our major partners include: Amadeus, Bouygues SA, Dassault, Peugeot, Sagem, Thales, Total.