This paper presents a cheap and easy‐to‐produce microprehensile microrobot on chip (MMOC). This four‐degree‐of‐freedom (DOFs) microprehensor is able to grip, hold and release submillimetric‐sized objects. The research conducted relied heavily on the design of a simple and efficient monolithic piezoelectric two‐DOF actuator, requiring no further motion transformation system and asking for no supplementary guiding system. The integration of all these functions in a single part eliminates nearly all assembly concerns. Each finger of the gripper is an actuator, called a duo‐bimorph, which provides higher deflections than piezoelectric tubes. The paper presents the developed MMOC prototype, comments its performances and details the functioning of the duo‐bimorph.

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The purpose of this paper is to describe the main problems concerning the design and operation of mixed-product assembly lines. We will focus on the design of assembly lines, which is most of the time composed in three steps. The first is the elaboration of the logical layout of the line, which consists in the distribution of operations among workstations along the line. The second is the choice of the most efficient product mix and production sequence in relation to the operation phase. The third is the subsequent elaboration of the physical layout of the line, i.e., deciding about the disposition of the workstations, conveyor(s), possible buffers, etc., on the shop floor. In this paper, the accent will be put exclusively on the first two steps. The concept of balance for ordering (BFO) is introduced to solve these two interrelated problems. After an overview of the current work in this area, this paper presents in detail a very promising approach to solve the BFO: the grouping and ordering genetic algorithms (genetic algorithms heavily modified to solve grouping/ordering problems). In all cases, the main concern is the quality of the resulting line in terms of cost and its suitability to the line designer's needs (special user preferences are followed as closely as possible). Academic and experimental results are presented, and they confirm the efficiency of the proposed approaches. The work presented here will be integrated in a complete design of assembly lines software, called CISAL. Further work will take resource dimension and reliability, cost, and buffer dimensioning into account.

The paper describes a new method to deal with the hybrid assembly line design, taking multiple objectives into account. It aims to assign a set of tasks to stations and to select the resources to perform each of them, while minimizing the total cost of the line and integrating design and operation issues. A grouping genetic algorithm was developed to solve the problem, hybridized with a branch-and-cut algorithm and the multicriteria decision-aid method PROMETHEE II. The study presents the method used for the allotment of tasks to stations and the determination of the assembly equipment used for each operation. It also introduces a manner to take into account user's preferences`transparently' in multiple objectives' design problems. The essential concepts adopted in this approach are described and the application of the algorithm to an industrial case study is presented.

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