helping a client right now to implement a solution from http://www.optimity.com.au

It is constraint based planning using optimization but what strikes me is the extreme ease of use. No complex and hard to understand parameters but very straight forward configuration once you have defined ABC classes for products and customers. Ideal for companies who do need to consider supply constraints as part of the replenishment planning process.

In manufacturing set ups where the process complexity is high, and variability of both supplies and demand is high and reworking of planning is very often an Advanced Planning Tool may be unsuitable. Here Daily Scheduling may be better off with a quick hueristic based Finite Scheduler

I’ve been doing this for an awfully long time and it just doesn’t seem that complicated to me. Dead nuts your planning factors in conjunction with how aggressive you want to get with your inventory turns, “manage” your supplier relationships to where you can bank on what they tell you mixed in with a little good old fashioned management by walking around….

Oh yea, and have your staff read “The Goal” – it’s a little less confusing.

Within APS (Advanced Planning and Scheduling) the better Constrained Planning (CP) systems fall under the Advanced Planning umbrella. Solutions of this type typically have a longer time horizon and higher level view of the underlying data as indicated in the article with all the described benefits.

Advanced Scheduling systems fill the gap where a broader coverage of the supply chain is needed (yet still within the confines of the own company), but a high level of detail is required. These systems cover all of FCS footprint but extend over material call-offs including all the constraints on these.

For example I encountered a scenario where bulk product was loaded in compartmentalized train wagons. Due to contamination constraints, the train compartments, the pipes feeding each compartment and the silos from which the pipes fed product all were under very tight scheduling constraints that require a solution of high level of detail. FCS does not cover the pipes and the train compartments, CP can cover them but lacks the level of detail needed, yet Advanced Scheduling solutions exist that cover the requirements perfectly.

Admittedly, this is a rare scenario, but there are other common scenarios that would benefit equally from breadth and detail of Advanced Scheduling.

For people who run factories it is important for them to identify what is the most valuable and expensive resource in the plant so they can make plans to protect it when things go wrong. FCS and CBP tend to become black boxes that do their calculation and present solutions that will be close to optimal but will confuse the operators. I would rather see factories simplify their production flow so it is very clear what the critical path is, and then consider implementing FCS or CBP. First, the factory will be more understandable to the operators and, second, it will make the solutions much easier for the analytical engines.

So I am all for optimizing factories and I tend to lean toward constraint based methods, but effort should be spent on simplifying the flow and ensuring the constraint is the constraint. In other words, as Goldratt would say subordinate all other operations to the necessity to exploit the constraint.

Ben