Serial- and hierarchical-batch scheduling: a systematic review and future research directions

As laser cutting and industrial 3D printing become increasingly important in many companies, so do the scheduling problems associated with them: serial-batch (sb) and hierarchical-batch (hb) scheduling. In sb-scheduling, the batch processing time is the sum of the processing times of the jobs in a batch. In hb-scheduling, the batch processing time results from sublevel decisions, such as 3D nesting. Both problems are challenging because of the interdependencies between the main decisions: grouping of jobs into batches and scheduling the batches. To that, we present a review and analysis of the literature on sb- and hb-scheduling using two classification schemes: The first is an extended Scheduling Problem Classification Scheme to specify batch scheduling problems. The second is a new Scheduling Article Classification Scheme developed to describe aspects like theoretical insights and solution methods. The schemes simplify the identification of research gaps and of relevant research (for academics and practitioners). In the literature synthesis process, 425 articles of all types of batching were reviewed. Due to the increasing importance of sb- and hb-scheduling, we focus our analysis on 119 articles which address these. As a result, we provide insights into the current state of research and highlight several topics for future research.