Process planning is an important and integral part of operating a printed circuit board (PCB) assembly system effectively. The focus of this research is to develop a new solution approach to determine the component placement sequence and feeder assignment for a turret style Chip Shooter machine often used in PCB assembly systems. This solution approach can be integrated into a process planning system to reduce assembly time and improve productivity. The Chip Shooter machine consists of three primary mechanisms: the turret head, a moving table, and the feeder carriage. These mechanisms move simultaneously in a cyclic manner to mount the components on the PCB. The mechanism with the longest movement time determines the placement time of a component. Therefore, the placement sequence of the components and the arrangement of the feeders in the feeder carriage directly affect the time required to mount all the components on a PCB. A placement time estimator function that accounts for the functional characteristic of the Chip Shooter machine is developed and is used to evaluate the performance of the solution approach presented in this research. The solution approach consists of a construction algorithm that uses a set of knowledge-based rules to construct an initial placement sequence and feeder assignment, and an improvement procedure to improve the initial solution. A case study is presented to validate the proposed solution approach. A Fuji CP4-3 machine and actual PCB data are used to test the performance of the proposed solution approach for different machine setup scenarios. The solutions obtained using the proposed solution approach are compared to those obtained using state of the art PCB assembly process optimization software. For all PCBs in the case study, the proposed solution approach yielded lower placement times than the commercial software, thus generating additional valuable production capacity. / Master of Science

Decreasing the cycle time of panels in the printed circuit card manufacturing process has been a significant research topic over the past decade. The research objective in such literature has been to reduce the placement machine cycle times by finding the optimal placement sequences and component-feeder allocation for a given, fixed, panel component layout for a given machine type. Until now, no research has been found which allows the alteration of the panel configuration itself, when panelization is a part of that electronic panel design. This research will be the first effort to incorporate panelization into the cycle time reduction field. The PCB circuit design is not to be altered; rather, the panel design (i.e., the arrangement of the PCB in the panel) is altered to reduce the panel assembly time. Component placement problem models are developed for three types of machines: The automated insertion machine (AIM), the pick-and-place (PAPM) machine, and the rotary turret head machine (RTHM). Two solution procedures are developed which are based upon a genetic algorithm (GA) approach. One procedure simultaneously produces solutions for the best panel design and component placement sequence. The other procedure first selects a best panel design based upon an estimation of its worth to the minimization problem. Then that procedure uses a more traditional GA to solve for the component placement and component type allocation problem for that panel design. Experiments were conducted to discover situations where the consideration of panelization can make a significant difierence in panel assembly times. It was shown that the PAPM scenario benefits most from panelization and the RTHM the least, though all three machine types show improvements under certain conditions established in the experiments. NOTE: An updated copy of this ETD was added on 09/17/2010. / Ph. D.

The fundamental requirement of the research reported within this thesis is the provision of physical models to enable model based simulation of mainstream printed circuit assembly (PCA) process discrete events for use within to-be-developed (or under development) software tools which codify cause & effects knowledge for use in product and process design optimisation. To support a national competitive advantage in high reliability electronics UK based producers of aircraft electronic subsystems require advanced simulation tools which offer model based guidance. In turn, maximization of manufacturability and minimization of uncontrolled rework must therefore enhance inservice sustainability for 'power-by-the-hour' commercial aircraft operation business models.

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