The purpose of this research is to develop an approach to minimize makespan for assigning boards to production lines. Because of sequence-dependent setup issue, board assignment and component allocation have to be performed concurrently. An integrated methodology is proposed to obtain a solution of the two problems. The methodology consists of seven phases: PCB grouping, family decomposition, subfamily sequencing, Keep Tool Needed Soonest (KTNS), component setup determination, component allocation, and board assignment. PCB grouping based on component similarity between boards is used to reduce the problem size. Family decomposition is used when total number of feeder slots required by a family exceeds feeder capacity. Subfamily sequencing and Keep Tool Needed Soonest are applied to minimize the number of component setups. Classification of setup components into standard, semi-standard, and custom setup components is performed to reduce the complexity of the component allocation problem. A component allocation algorithm is developed to balance workload across machines. Assigning board families to production lines is performed using a modification of Longest Processing Time (LPT) rule. Assigning entire PCB families to production lines to minimize makespan is difficult to accomplish since the amount of production time for each family is very large compared to that of individual PCB lot. Splitting some subfamilies is allowed as long as this does not increase makespan. The PCB grouping, family decomposition, subfamily sequencing, Keep Tool Needed Soonest (KTNS), and component setup determination procedures are derived from published research results. The component allocation and board assignment are developed in this research, as well as an overall methodology to integrate the entire problem. Data provided by published literature are employed to evaluate performance of the component allocation algorithm and the integrated methodology. To examine the applicability of the methodology, an industrial data is used with the total imbalance due to setup time and placement time of individual PCB and global makespan as the performance measures. Experimentation is conducted with simulated data based on an industry data to investigate impact of threshold value, feeder capacity, and characteristics of data sets on system performance. / Graduation date: 2002

Graduation date: 1992

Flexible printed circuits (FPCs) have a flexible character, so the topic for high accuracy and speed of drill is important. We will create an automatic system that joins vision-guided function to accomplish the challenge object of high quality and low cost. The system must contain two sub-systems, which are the machine position control and the image recognition. The machine position control system basis framework moves to position after getting hole-position with different methods and scheme of trajectory planning. The image recognition system framework exports correction to machine position control system that integrates the technique of charge-coupled device (CCD), light source design, snap an image in region of interest (ROI) with image grabber card, pattern match that uses normalized cross correlation (NCC) algorithm. We can proof that the system can achieve the expected goal of high speed and accuracy of drill.

Thesis (Ph. D.)--School of Chemical Engineering, Georgia Institute of Technology, 2004. Directed by Clifford L. Henderson. / Includes bibliographical references (leaves 366-371).

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