Delchambre (1990, 1991) and Delchambre and A. Wafflard (1991) presented an automatic and user-friendly approach to computer-aided assembly planning. The authors give a brief summary of the assembly planner's specifications and of the methodology used to generate the assembly. Industrial case studies are presented to illustrate the various stages of the assembly sequence generation. User-friendly formalisms to represent the intermediate and final results to the user are outlined. The proposed approach is user-friendly because the intermediate and final results presented were easily understandable by the user despite the combinatorial explosion of results. The industrial prototype of the assembly planner and the user interaction with the system are discussed. Several results obtained with this prototype are presented and discussed on the basis of the industrial case studies.>

The authors introduce the idea of constraint-based scheduling and consider some constraints as a good factor in scheduling. The idea is used to develop a novel scheduling method. A schedule problem is used to present the method. The parallel-serial plan (PSP) is defined. A recursive approach to find the best scheduling for a PSP is outlined. The complexity of the algorithm is discussed, and the algorithm is extended for the scheduling of a plan.>

A current trend in assembly robotics is to use several robots with different skills that work together inside an assembly cell. The authors describe an approach to the control of such an assembly cell. The underlying idea is to minimize as much as possible to computations that have to be done online, leaving time for the control strategy. The resulting control structure is thus a database of offline computed facts which act as inputs to the online supervisor. The proposed approach was tested on a two-robot assembly cell and showed satisfactory performance.>