Paint bank sequence optimization on assembly in an automotive manufacturing plant

Automotive assembly plants are tasked with building vehicles which have many different available options. In the bank between paint and assembly, the cycle time variation required in final assembly makes it advantageous to re-sequence the vehicles leaving the paint shop using scheduling restrictions. The paint bank sequence impact on assembly shop restrictions has been an ongoing issue in the automotive manufacturing industry. Since the sequence fed into the body shop will remain close to the input sequence, the performance of the body shop is considered to be negligible. On the other hand, the paint shop greatly affect's the sequence of vehicles that are fed into final assembly. Most vehicle sequence disruptions occur in the paint shop area. This leads to the greatest number of issues in sequencing vehicles feeding final assembly. These difficulties are what led many companies to utilize the Automatic Storage and Retrieval System (AS/RS) for re-sequencing and sending the optimal vehicle sequence into final assembly. The AS/RS is a large bank between paint and final assembly; it is known as a paint bank. It utilizes a sequencing algorithm that chooses the vehicle order. The performance of the paint bank is measured by the number of violations the sequence has for the final assembly option's constraints.;This dissertation provides methods to create a valid representation of a paint shop in the automotive manufacturing industry. Based on the validity of the model, continued performance analyses and improvements were conducted. The sequencing of vehicles was also investigated due to the negative impact of sending option related violations into final assembly. Option related violations entering into final assembly impact throughput, cost, and quality. To address the sequencing problem, a heuristic sequencing algorithm for the paint-to-assembly bank was developed. This dissertation provides the following: critical information used in the simulation model, a literature review of the research area, and the results associated with using a heuristic algorithm in the paint-to-assembly bank. Therefore, the contributions of this applied research project are; (a) developing the heuristic algorithm for the paint-to-assembly bank and analyzing and evaluating bank configurations, (b) the evaluation of the impact of changes to the product mix as well as to the vehicle options through performance analysis on the final assembly schedule based on paint shop disruption, and (c) analyzing the violation effect on the sequence where the violations are counted based on the assembly shop restrictions through the use of a penalty function. This research yielded that a single bank 6-lane design utilizing the developed heuristic algorithm provides reduction of 5 jobs per day (JPD) lost from 32 to 27, meaning the total daily throughput is increased, yielding a total option violation improvement of 16%.