Prevent Anchor Drift

Sample customization that prevents anchored activities from drifting when not constrainted


  1. After each optimize, the customization tracks the start and end dates, along with the materials, for every anchored activity.
  2. During Optimize, before an activity is allowed to scheduled it is checked for the following conditions:
    1. The scheduled dates will not overlap an anchored activity.
    2. Materials used will not reduce availability for any anchored activity.
  3. This customization does not attempt to solve for every case of anchor drift. For example, multi-tasking resources, max delay, transfer quantity, and other advanced scheduling features will require further development if needed. Also, any constraints will still be applied to anchored activities including material shortages, capacity changes, etc that are introduced through data updates. The material must have a warehouse mapped to it or a null value will be defaulted.

How this can be expanded:

  • This customization can be enhanced to remove most of the limitations. Max delay and keep successors no interrupt may be the exceptions.

Customization Points:

The PostSimStageCustomization tracks anchored activities.

The OperationScheduled point is used to track material availability.

The Schedulability customization prevents scheduling activities that would delay and anchored activity.


Project file:

Customization File

Version 11.37.11 and later: NoAchorDrift.dll