First Class Scheduler
A system for generation of rotating workforce schedules
In this project the aim was to develop algorithms that will automate the process of generating rotating workforce schedules for the XIMES GmbH, which specializes in developing software and in consulting on work-hour arrangements. The efficiency of the algorithms and the quality of their solutions are the two most important criteria. In the consulting process, it is essential that a solution be produced in a very short time, so that it can be discussed further. Quality of workforce schedules generated by First Class Scheduler (FCS) should be at least as good as solutions delivered by professional planners.
Results of research
We propose and implement a new framework for computerized rotating workforce scheduling, including intelligent backtracking algorithms for each stage of the framework. The new framework consist of the following steps: (1) choosing a set of lengths for the work blocks (a work block is a sequence of consecutive days of work), (2) choosing a particular sequence of blocks of work and days-off blocks amongst those that have optimal weekend characteristics, (3) enumerating possible shift sequences for the chosen work blocks subject to shift change constraints and bounds on sequences of shifts, and (4) assignment of shift sequences to work blocks while fulfilling the staffing requirements. The combination of constraint satisfaction with problem-oriented intelligent backtracking algorithms in each of the four steps can produce good solutions for real-world problems in acceptable time. Apart from the fact that the generated schedules meet all of the hard constraints, the new framework also allows for the incorporation of the preferences of the decision-maker with regard to soft constraints that are otherwise more difficult to assess and model. Computational results from benchmark examples found both in the literature and in real-world problems confirm the viability of our approach. (for detailed description of algorithms see publications)
We included algorithms and other parts that allow taking into account the user in the decision-making process in commercial product First Class Scheduler (FCS). FCS is a part of the commercial product SHIFTPLAN-ASSISTANT (SPA 4.0) of XIMES GmbH. In this system, the generation of rotating schedules is conducted by interacting with the decision maker based on the new framework. In FCS most important constraints in the central European context can be modeled. This package is already internationally highly appreciated and exists in German, English, Finnish and Dutch. The product is used successfully since the year 2000 in several organizations by the consultants of XIMES GmbH for generating rotating workforce schedules. The system is also installed and works in many organizations. According to the consultants of the XIMES GmbH FCS can solve successfully 80 to 90% of problems of rotating workforce schedules that appear in practice. (see screenshots of system)