A priori checking inconsistencies among strategic constraints for assembly plan generation.

International audienceThis paper is related to the field of assembly plan generation. It describes a new approach to a priori check the consistency of an assembly strategy that is given by the assembly system designers before running an assembly plan generation algorithm. The aim of this work is to improve the assembly plan designer's efficiency by reducing the research space while proving the existence of acceptable solutions. The assembly strategy combined with the product's model implies a set of constraints on the assembly processes. The proposed method determines whether the given assembly strategy produces possible assembly processes. In case of inconsistencies among the strategic constraints, the method will help the designer to identify the contradictory constraints. The set of constraints can be expressed by a Boolean equation. First we present the key concepts and models related to the product, processes and added values in the field of assembly plan generation. Second we define existing strategic constraints, and propose three new ones and a classification of strategic assembly constraints. The originality of the proposed method consists in defining an elementary strategic constraint that is used to describe every other constraint. The proposed method leads to model an assembly strategy by a single Boolean equation that is used to check the inconsistencies. An industrial case study is provided to highlight and to demonstrate the interests of this approach

Control of a team of micro-robots for non-invasive medical applications

National audienceThis paper deals with the control and the synchronisation of a team of micro-robots that performs a non-invasive surgical act into a human body. These micro-robots are very small sized (from ten to some hundred microns). A single unit embeds the minimum of computing power and memory (minimalist electronics) to run a very light program, such as a finite-state machine. The mass effect of the joined micro-robots will allow to achieve the mission through a satisfactory way. The originality of this work being to consider a micro-robot as a disposable unit, which has to be as simple as possible, we need to combine reduced computing power with recent architectures. Some kinds of mission are described and the most promising is detailed. Preliminary simulations support our approach

Unification of the a priori inconsistencies checking among assembly constraints in assembly sequence planning.

International audienceSequence planning generation is an important problem in assembly line design. A good assembly sequence can help to reduce the cost and time of the manufacturing process. This paper focuses on assembly sequence planning (ASP) known as a hard combinatorial optimization problem. Although the ASP problem has been tackled via even more sophisticated optimization techniques, these techniques are often inefficient for proposing feasible assembly sequences that satisfy the assembly planners' preferences. This paper presents an approach that makes easier to check the validity of operations in assembly process. It is based on a model of the assembly planners' preferences by means of strategic constraints. It helps to check a priori the consistency of the assembly constraints (strategic an operative constraints) given by the assembly system designers before and while running an assembly plan generation algorithm. This approach reduces the solution space significantly

New bottom-up algorithm for assembly plan generation : opportunities for micro-factory design.

International audienceThis paper discusses a new approach dedicated to assembly plan generation, called "bottom-up algorithm". It is compared to the traditional "top-down approach", usually used to perform this stage of the design process of the assembly systems for "macro-products". We explore why this new algorithm is better adapted for designing a microassembly system. The case of watch assembly plans generation is described through the both approaches and the obtained results are compared

Nouvelle approche dans l'analyse pour la conception des systèmes de production appliquée aux microcomposants.

International audienceAujourd'hui, on trouve des microproduits dans de nombreux domaines : médical, son, image, constituants de l'automobile, électroménager. De nouveaux appareils de production adaptés doivent être développés pour répondre à une fabrication bien particulière et une demande en forte croissance. Dans le soucis d'intégrer à la fois des contraintes fonctionnelles et technologiques dans une approche modulaire, les travaux développés au Laboratoire d'Automatique de Besançon ont pour but de mettre sur pied une démarche originale pour obtenir, à moindre effort et à moindre coût un système de production adapté aux microproduits qui soit à la fois productif, efficient et adaptatif

A generic approach for a micro parts feeding system.

International audienceThe paper propose a new approach in order to design a generic microparts feeder. The method based on a classification scheme allows to emerge the principal characteristics of each studies solutions. The different criteria take into account the specifities of the micro world and moreover the main characteristics for the feeding functions. Thus, we analyse three systems and confront them to find the generic and flexibility aspects

On Disassembly Workshop Model Integration for Disassembly Planning

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