Research On The Work-Rest Scheduling Of The Manual Picking To Consider Human Factor

As the status of sorting operation in the warehousing and distribution system has beenraised, the work-rest scheduling of picking becomes particularly important. Althoughscience and technology have developed rapidly, then manual operation is stillessential and indispensible. On the one hand, previous researches focused on thestudy of the sequencing, ignoring human factors. On the other hand, objectivefunction was too single and completing time was always considered as the onlyobjective. Thus, the work-rest schedule model of manual picking is constructed,where two objectives include minimizing the picking time and minimizing pickingerror rate. In this paper, there are models involved. That is picker-to-parts systems andparts-to-picker systems. On the basis of the level of workers’ fatigue, workload andthe maximum time of picking, human error rate and energy threshold are introducedinto the two proposed models. In addition, a GA-based algorithm is used. The casestudies of the two models is used to confirm that the models are effective. Then, fivefeasibility solutions can be obtained in each case study. Decision makers can chooseone from them and it is beneficial to assess the entire picking system.