Advanced Planning and Scheduling Software Overview
As Finite Capacity Scheduling software has evolved and become more feature rich, it has become known as Advanced Planning and Scheduling software (APS software). Not only does Advanced Planning and Scheduling software consider material, but it has the ability to perform bill of material explosions which net on hand inventory and net projected inventory receipts through purchase orders and manufacturing orders. Once inventory is netted, Advanced Planning and Scheduling software creates purchase orders and manufacturing orders to satisfy demand based on safety stock levels and lot sizing logic. When scheduling, Advanced Planning and Scheduling software dynamically allocates inventory and projected inventory receipts to production orders. If material is made constraining, the software then delays production based on the available of inventory generated by allocated orders.
Advanced Production Scheduling software can be of significant benefit in production environments where there are more than two levels in bills of material. Previous scheduling techniques couldn’t delay the start of upper level items based on the schedule of components. This limitation only allowed effective scheduling of released orders for which material is available. Previous scheduling techniques also required manual means or MRP modules to explode bills of material. Given the delay associated with this process, it was impossible to make timely delivery commitments to customers.
Advanced Planning and Scheduling Software’s enhanced functionality helps you:
- extend the planning and scheduling horizon for as long as there is demand to drive it. Since demand includes sales orders and forecasts, the only practical limits are forecast accuracy and computer processing speeds
- quickly make accurate deliver commitments to customers. Called Capable-to-Promise (CTP), this feature often replaces the inaccurate, infinite scheduling based Available-to-Promise (ATP) features in ERP systems
- dynamically allocate and re-allocate inventory to upper level demand
- perform multi-plant planning and scheduling which answers questions such as “in which plant should this production be sited?”
- plan throughout the supply chain
Advanced Planning and Scheduling Software Replaces MRPII Planning
Advanced Planning and Scheduling software allows you to replace some or all of MRPII’s traditional production planning / scheduling and capacity planning. As shown in the left panel of the diagram below, the MRPII model for planning and scheduling advocates the use of different approaches (Production Planning, Master Production Scheduling, Material Requirements Planning, Production Activity Control) over different time horizons. Each approach has its own version of Capacity Planning to identify and adjust for capacity imbalances. Since these capacity planning approaches assume infinite capacity and static lead times, none works particularly well.
Given its ability to explode bills of material and its ability to explicitly consider capacity, the whole MRPII planning and scheduling paradigm can be replaced with an effective Advanced Planning and Scheduling module as outlined in the right panel of the diagram below.
