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The purpose of this paper is to investigate the optimization for a placement machine in printed circuit board (PCB) assembly when family setup strategy is adopted.

A complete mathematical model is developed for the integrated problem to optimize feeder arrangement and component placement sequences so as to minimize the makespan for a set of PCB batches. Owing to the complexity of the problem, a specific genetic algorithm (GA) is proposed.

The established model is able to find the minimal makespan for a set of PCB batches through determining the feeder arrangement and placement sequences. However, exact solutions to the problem are not practical due to the complexity. Experimental tests show that the proposed GA can solve the problem both effectively and efficiently.

When a placement machine is set up for production of a set of PCB batches, the feeder arrangement of the machine together with the component placement sequencing for each PCB type should be solved simultaneously so as to minimize the overall makespan.

The paper investigates the optimization for PCB assembly with family setup strategy, which is adopted by many PCB manufacturers for reducing both setup costs and human errors.

The paper investigates the feeder arrangement and placement sequencing problems when family setup strategy is adopted, which has not been studied in the literature.

The purpose of this paper is to examine how rural outlaws, known in the Australian context as bushrangers, impacted on the introduction of itinerant teaching in sparsely settled areas under the Council of Education in the colony of New South Wales. In July 1867 the evolving process for establishing half-time schools was suddenly disrupted when itinerant teaching diverged down an unexpected and uncharted path. As a result the first two itinerant teachers were appointed and taught in an irregular manner that differed significantly from regulation and convention. The catalyst was a series of events arising from bushranging that was prevalent in the Braidwood area in the mid-1860s.

The paper draws on archival sources, particularly sources within State Archives and Records NSW, further contemporary sources such as reports and newspapers; and on secondary sources.

The paper reveals the circumstances which led to the implementation of an unanticipated form of itinerant teaching in the “Jingeras”; the impact of rural banditry or bushranging, on the nature and conduct of these early half-time schools; and the processes of policy formation involved.

This study is the first to explore the causes behind the marked deviation from the intended form and conduct of half-time schools that occurred in the Braidwood area of 1860s New South Wales. It provides a detailed account of how schooling was employed to counter rural banditry, or bushranging, in the Jingeras and provided significant insight into the education policy formation processes of the time.

Assembly variation analysis generally demands probability distributions of variation sources. However, due to small production volume in aircraft manufacturing, especially prototype manufacturing, the probability distributions are hard to obtain, and only the small-sample data of variation sources can be consulted. Thus, this paper aims to propose a variation analysis method driven by small-sample data for compliant aero-structure assembly.

First, a hybrid assembly variation model, integrating rigid effects with flexibility, is constructed based on the homogeneous transformation and elasticity mechanics. Then, the bootstrap approach is introduced to estimate a variation source based on small-sample data. The influences of bootstrap parameters on the estimation accuracy are analyzed to select suitable parameters for acceptable estimation performance. Finally, the process of assembly variation analysis driven by small-sample data is demonstrated.

A variation analysis method driven by small-sample data, considering both rigid effects and flexibility, is proposed for aero-structure assembly. The method provides a good complement to traditional variation analysis methods based on probability distributions of variation sources.

With the proposed method, even if probability distribution information of variation sources cannot be obtained, accurate estimation of the assembly variation could be achieved. The method is well suited for aircraft assembly, especially in the stage of prototype manufacturing.

A variation analysis method driven by small-sample data is proposed for aero-structure assembly, which can be extended to deal with other similar applications.

The purpose of this paper is to propose a new assembly variation analysis model to analyze assembly variation for sheet metal parts. The main focus is to analyze assembly processes based on the method of power balance.

Starting with issues in assembly variation analysis, the review shows the critical aspects of tolerance analysis. The method of influence coefficient (MIC) cannot accurately analyze the relationship between part variations and assembly variations, as the welding point is not a point but a small area. Therefore, new sensitivity matrices are generated based on the method of power balance.

Here two cases illustrate the processes of assembly variation analysis, and the results indicate that new method has higher accuracy than the MIC.

This study is limited to assembly variation analysis for sheet metal parts, which can be used in auto-body and airplane body.

This paper provides a new assembly variation analysis based on the method of power balance.

Seiko watches are produced on automatic assembly lines by three methods: System A for mechanical watches, System B for digital watches and now System C is being developed to give greater flexibility.

The purpose of this paper is to review the International Manufacturing Technology Show in Chicago with emphasis on innovations in applying automation to manufacturing and assembly.

In‐depth interviews with exhibitors of automated assembly and manufacturing technology.

Building of production machinery continues to move toward offering automated assembly or production cells and away from building single purpose metal cutting machinery. Robots are married to machine tools for much more than just tending.

The paper shows that users in almost any manufacturing realm will find that automated manufacturing technologies are now addressing all types of production requirements. No longer it is necessary to think that only million off part runs can be produced in an automated manner. Machine tool builders are including testing, finishing, marking, assembly and other secondary operations within the basic machining unit for a wide range of production volumes. Automation can even be applied to “made to order” type production.

Material variation is inevitable in volume production, especially the sheet metal thickness variation, which influences part stiffness characteristic. The purpose of this paper is to present a new variation model of compliant sheet metal assembly with consideration of material variation influence.

The theory of computational solid mechanics is used to obtain the relationship between part stiffness matrix and material characteristic. The method of influence coefficients is adopted to deduce the assembly variation model.

Material variation‐induced influence coefficients to assembly variation are obtained, and a variation model of compliant sheet metal assembly with sources of material variations, part geometric variations and fixture variations is presented. Analysis shows that material variation has an important influence to assembly variations.

A quantitative relationship between assembly variations and material thickness variations is firstly given and a new variation model of compliant sheet metal assembly is presented to help designers to more exactly predict the assembly variation and diagnose variation sources.

MAKE no mistake about it, robots are not just here to stay static: their use will extend far beyond the very dreams of their earliest inventors, and who they were is lost under the veils of age‐long antiquity.