Model Critical Constraints

Impact of Constraints on Schedule

In traditional APS the tool itself often limits the constraints that can be included in the schedule. Many optimization-based tools are further limited by their need to keep the model formulation small and simple so that the solver can generate a solution in a reasonable time. However when constraints are ignored these tools produce schedules that initially appear to be feasible, but are unrealistic in the real system.

An example of a critical constraint that is typically ignored is material handling devices such as AGV's or forklift trucks that are used for moving material between workstations. If considered at all, these constraints are approximated in the schedule as an "average" and constant move time independent of the congestion in system. However in cases where we are employing transfer lot sizes to reduce WIP, the timely availability and movements of material handling devices can be a critical constraint.

Model any Constraint with Simio

Use Simio's RPS capability to mitigate risk, meet schedule, and reduce cost.

Simio Enterprise Edition featuring detailed production scheduling uses a simulation-based approach to scheduling that is built around a purpose built Simio model of the system. The key advantage of this is that you have available to you the full modeling power of the Simio simulation software to fully capture the constraints in your system. You can model your system using the Simio Standard Library of objects, or if needed you can create your own custom objects for modeling complex systems. You can include moving material devices such as forklift trucks or AGV's (along with the congestion that occurs on their travel paths) as well as complex material handling devices such as cranes and conveyors. You can also accurately model complex workstations such as ovens and machining centers with tool changers.

Simio Enterprise imposes no restrictions on the type and number of constraints included in the model. With Simio Enterprise you no longer have to assume away critical constraints in your production system. You can generate both the deterministic plan and associated risk analysis using a model that fully captures the realities of your complex production and supply chain.

Proceed to the next topic or click on any item in the summary box on the right to learn more about the business benefits of detailed production scheduling.

What's Next?

Learn more about the business benefits of detailed production scheduling: Click here for a Complimentary White Paper

Why detailed production scheduling from Simio