Sequencing and Scheduling in Robotic Cells: Recent Developments

Abstract

A great deal of work has been done to analyze the problem of robot move sequencing and part scheduling in robotic flowshop cells. We examine the recent developments in this literature. A robotic flowshop cell consists of a number of processing stages served by one or more robots. Each stage has one or more machines that perform that stage's processing. Types of robotic cells are differentiated from one another by certain characteristics, including robot type, robot travel-time, number of robots, types of parts processed, and use of parallel machines within stages. We focus on cyclic production of parts. A cycle is specified by a repeatable sequence of robot moves designed to transfer a set of parts between the machines for their processing.We start by providing a classification scheme for robotic cell scheduling problems that is based on three characteristics: machine environment, processing restrictions, and objective function, and discuss the influence of these characteristics on the methods of analysis employed. In addition to reporting recent results on classical robotic cell scheduling problems, we include results on robotic cells with advanced features such as dual gripper robots, parallel machines, and multiple robots. Next, we examine implementation issues that have been addressed in the practice-oriented literature and detail the optimal policies to use under various combinations of conditions. We conclude by describing some important open problems in the field.

Scheduling Analysis of Cluster Tools with Buffer/Process Modules

“…A one-wafer action sequence is defined as a sequence of robot actions which pick and place each module exactly once [2]. In [3], [4], analytical models of steady-state throughput are discussed for a cluster tool equipped with single-blade and double-blade robots.…”

“…For a double-blade robot, Venkatesh et al [4] propose one optimal schedule by a "swap" action. Dawande et al [2] summarize the sequencing and scheduling in robotic cells, which is similar to cluster tools. Geismar et al [5] extend the result in [6] and discuss the throughput and scheduling analysis of a robotic cell with a single-gripper robot and parallel stations.…”

“…We also call cluster C i a transfer cluster if (1) R i is a singleblade robot, (2) there is no process module in C i , and (3) both side buffer modules (or BPM) have one-wafer capacities. Due to the fact that there is not enough wafer storage space to flexibly move wafers, we will handle transfer clusters slightly different.…”

Research on Model and Mechanism of Autonomous Management for Cellular Manufacturing

“…Multi-species batch production enterprises take the cellular manufacturing have become a development trend. In recent years, foreign studies more focused on physical and technical factors of equipment layout and production processes [1][2][3][4], as well as the production organizational forms and technical support based on multi-enterprise co-production [5,6]. China's theoretical according to the status and existing problems in Chinese manufacturing, had done many researches on the construction of production cells and network production systems, production scheduling in the cases of single enterprise and multi-enterprise cooperation [7,8].…”

Bicriteria robotic cell scheduling

“…There is an extensive literature on robotic cell scheduling problems with surveys including Crama et al (2000) and Dawande et al (2005). An n-unit cycle can be defined as a robot move cycle which produces exactly n units and ends up with the same state of the cell as the starting state.…”