Conception de montage d’usinage : placement des éléments technologiques en contact avec la pièce

Le choix des éléments technologiques constituant le montage d’usinage et tout particulièrement les éléments en contact avec la pièce joue un rôle primordial dans la qualité de la pièce usinée. L’objectif de ce papier est d’une part de définir une méthodologie de choix des éléments technologiques en contact avec la pièce et d’autre part de proposer une stratégie de placement

Efficient determination of four-point form-closure optimal constraints of polygonal objects

This paper proposes a new and more efficient solution to the problem of determining optimal form-closure constraints of polygonal objects using four contacts. New grasp parameters are determined based only on the directions of the applied forces, which are then used to determine the optimal grasp. Given a set of contact edges, using an analytical procedure a solution that is either the optimal one or is very close to it is obtained (only in this second case an iterative procedure is needed to find a root of a nonlinear equation). This procedure is used for an efficient determination of the optimal grasp on the whole object. The algorithms have been implemented and numerical examples are shown. Note to Practitioners—This paper presents an algorithm that improves previous approaches in terms of efficiency in the determination of the optimal object constraint maximizing the minimum wrench that the object can support in any direction. The problem can always be solved using numerical optimization techniques but when time is relevant an efficient algorithm becomes of interest. Practical applications include optimal determination of fixtures and object grasps.Peer ReviewedPostprint (published version

COMPUTER-AIDED FIXTURE PLANNING: A REVIEW

Fixture planning is a complex activity restricted by the extreme diversity of workpieces and constraints of design geometry, part accessibility, working force, and component deformation. This paper reviews major approaches to computer-aided fixture planning (CAFP). Geometry methods, kinematical analysis, force analysis, deformation analysis, case-base reasoning, fixture assembly planning, feature-based methods, rule-based methods and optimization methods are surveyed. The CAFP systems are summarized as CAD-based systems and Web-based systems. Some promising research areas are identified in respect of fixture design, assembly planning and virtual fixture planning

Modeling, analysis and verification of optimal fixture design

Master'sMASTER OF ENGINEERIN

Collaborative fixture design and analysis system with robustness for machining parts

Ph.DDOCTOR OF PHILOSOPH

Razvoj sistema za projektovanje i optimizaciju konstrukcije pribora

U disertaciji se prikazuje razvoj sistema za projektovanje i optimizaciju konstrukcije pribora za mašinsku obradu. Analizirani su različiti prilazi u projektovanu pribora. Prikazana je koncepcija i funkcionisanje razvijenog sistema. Validacija sistema je izvršena na konkternim radnim predmetima za operacije obrade bušenja i glodanja. Na kraju su dati odgovarajući zaključci i mogući pravci budućih istraživanjaThe dissertation shows the development of system for fixture design and layout optimization for machining processi. Different approaches were analyzed in fixture design. The concept and functioning of the developed system is presented. Validation of the system is made with specific workpieces for drilling and milling process operations. At the end the appropriate conclusions and possible directions for future research are given