Analysis of a Worker Assignment Model in a Lean Manufacturing Environment

This paper describes an expansion of a multi-period worker assignment model for a lean production cell that produces a single product family. The hypothetical cell operates eight hours per day, twenty days per month and has six workers performing ten tasks. The model assigns the workers to tasks and determines the levels of additional training that may be necessary to meet customer demand, quality requirements, and cross-training provisions. The two main factors analyzed are the number of workers trained beyond two tasks and frequency of job rotation. Four levels of worker training and three levels of job rotation frequency are evaluated. To be considered cross-trained, workers must be trained on at least two tasks. The four levels of worker training are zero, two, four, and six workers trained on more than two tasks. The zero level indicates that all workers are trained on only two tasks, while the other three levels indicate that that number of workers are trained on more than two tasks. The three levels of job rotation are eight, four, and two hour rotations per day. The solutions from the model are analyzed to determine the impact the two factors have on net present costs, quality costs, and training within the work month. The model expands upon the research of McDonald et. al., [1] by allowing workers to increase their training by more than a single skill level during the 20-day planning period and by removing the budgetary constraints for training. The results of this model are expected to provide insight on the impact worker training and job rotation frequencies have on production line performance and provide guidance on training policies.