Simulation Based Scheduling
Atlantic Scheduler is a simulation based finite capacity scheduling tool. It enables schedulers to:
- Schedule activities on work centers or facilities to produce products to meet customer demand
- Schedule distribution activities to move products from one location to another
- Schedule activities to replenish inventories
- Simulate activity start and end times given production rates on different facilities
- Simulate changeover or setup times and costs given the sequence of scheduled activities
- Run a variety of automatic scheduling tools or algorithms to solve scheduling problems
The Simulation Engine
The simulator in Atlantic Scheduler deals with continuous time; there is no need to specify time slice size to find the balance between approximation error and run time. Instead, the simulator moves from event to event, e.g., scheduled activities starting and ending, in order to calculate setups, deal with shutdowns, and to project changes in inventory. Thus, for every inventory change event, the simulator knows which scheduled activity caused the change. This information has allowed us to write a new breed of powerful scheduling algorithms.
Schedulers modify the schedule by dragging scheduled activities earlier or later in time or dragging an activity to a different facility. Once an activity is moved, the simulator automatically re-calculates the start and end times of surrounding activites. Changeover or setup costs and times are also automatically re-caculated.
Schedulers have two different user interfaces for interacting with the schedule: the Scheduling Board and the Scheduling Grid. The Scheduling Board is a pivotable Gantt Chart that shows multiple facilities graphically. Schedulers click on activities to modify or drag-and-drop them. The Scheduling Grid is a spreadsheet-like view of a facility schedules. Again, users can edit activites by clicking on them or by dragging them to another location in the schedule. The Scheduling Grid is designed to be easily viewable from mobile phones and tablets.
A Different Approach to Schedule Optimization
Atlantic Scheduler includes a multitude of optimization tools to create an initial schedule and react to enterprise changes like new customer orders, completed production, unexpected downtime and production upsets. Based on the information provided by the simulator, a large library of basic scheduling functions have been developed, e.g., 'solve this negative inventory problem' or 'find a better place for this scheduled activity'. This library of basic scheduling functions is used in the higher level scheduling algorithms that the user can call from the Scheduling Board. And those higher level scheduling algorithms are called by even higher level scheduling algorithms like The Bot, which analyze the current schedule, apply a series of algorithms, analyze performance, apply other algorithms, etc. In this hierarchy of algorithms, however, the user still has control. From the Scheduling Board, the user can select scheduled activities or products to direct the focus of any chosen algorithm.