A Regression-Based Cycle Time Estimator for the PCB Placement Machine

The assembly of printed circuit boards is conducted by the sophisticated PCB placement machines. The cycle time for a machine to complete an assembly job is determined by solving two machine optimization problems, i.e., the feeder arrangement and placement sequencing.Rapid and accurate estimation of these cycle times is important for solving the higher level planning problems including the line balancing problem. In this paper, a regression-based estimator was established to estimate the cycle time. Statistical results on 100 PCB samples showed that the proposed estimator could estimate the cycle times accurately. At the same time, the computationally efficiency makes it suitableto be used in solving higher level planning problems.

Optimizing the Performance of Chip Shooter Machine Based on Ant Colony Algorithm

The component placement sequence and feeder arrangement are two critical factors determining the assembly time of chip-shooter machine (CS). In addition, the different size of component and different arrangement strategy affect the feeder arrangement and component placement sequence. Based on the engineering analysis, an integrated optimization model of printed circuit board (PCB) assembly for CS machine is established. According to the parallel placement character of CS machine, "Max-Min Ant Colony Algorithm with Communication function (MMAC)" is designed based on traditional Ant Colony Algorithm. The idea that two ants with different duties collaborate to solve the optimization problem is presented. Guide ants optimize placement sequence while executant ants optimize feeder arrangement according to the components placement sequence. The component placement sequence and feeder arrangement are optimized simultaneously

Placement Time Optimization of Chip Mounter by Genetic Algorithms - Search for Optimal Tape Feeder Arrangement -

Genetic algorithms (GAs) are applied to searching for tape feeder arrangement to optimize placement time of chip mounters where a combination of parts placement sequence and tape feeder arrangement affect placement time under constraints. Compared to general GAs, our improved tape feeder arrangement GA using a new genetic operator called rotation was confirmed effective for multihead chip mounters handling several parts at once.