Improving well-being and efficiency in order picking

For processes that rely largely on manual activities, such as order picking, human factors need to be considered for aligning decision-making with actual system performance. This paper proposes a joint order picking batching and sequencing problem formulation with worker fatigue modeling. The fatigue level induces a decrease in performance, thus making the picking time for any batch dependent on prior sequence position decisions. Moreover, overly fatigued operators may necessitate rests. This optimization problem is solved with Adaptive Large Neighborhood Search meta-heuristic for a realistic warehousing scenario. It is shown how considering the fatigue effect can improve both efficiency and worker well-being.