Family tables inside of Creo are a wonderful and efficient method to create variants for a design that is similar but not identical to other designs.
Family table functionality has been around since early Pro/ENGINEER versions and PRIOR to any PDM management software that manages these files. The tables that contain the information are stored inside of a single GENERIC file that gets altered during a session of Creo Parametric into the variant that is called an INSTANCE.
The challenge of family tables and PDM software is the requirement of this table to continuously be managed and ‘verified’ by the system for each ‘instance’. Once the system inherits this table and extracts each ‘instance’ they are viewed inside of the PDM system as individual items with unique and separate life cycle states and revisions.
So, we have a system that foundationally must always rely on this table and it’s ‘generic’ in order to successfully regenerate each individual ‘instance’ that is derived from this table. Complexities arise when ‘instances’ become corrupted, discontinued, altered unexpectedly, or simply deleted from the table. These problems usually create great effort to resolve and many hours are spent trying to fix these issues in order to successfully ‘check in’ a family table-based component.
On a product design side, family tables tend to also be used as ‘config management’ vs ‘design variant’ and users overextend the usage in order to quickly create new configurations of assemblies. At the very beginning this isn’t an problematic issue but over many years these tables tend to build up with hundreds of rows and columns which can be very difficult to manage … entering new data and creating new variants can be very problematic and time consuming, never mind the problems they can create later on in the PDM management software.
An 80/20 rule should be applied to tables so that when a design is not 80% or more IDENTICAL to the generic it should NOT be part of the table and should be an individual component with no relation to the original table.
This rule is very difficult to implement as it takes time for the user to create stand-alone models and then alter them after the fact vs simply adding new row and new values into the table. To further aggravate the situation, users tend to simply open a new instance and begin working and adding features to that instance and then these alterations are recorded by Creo Parametric as ‘system added columns’ that are added automatically, unknowingly by the user, which further creates more complexity to the size of the table.
You will see these columns often have many instances have asterisks (*) in the values which indicate that it’s just done by the system and defaulted to the generic values.
It is recommended practice to truncate or ‘cut off’ the usage of family tables and create variants using a much different yet similar method.
Family Table Based Design
Family Table Functionalities
- Create variants of: Dimension, Feature, Merge Part, Component, Parameter, Ref Model, Group & Pattern Table
- Stores information in table as an ‘instance’
- Often referred to as an ‘overbuilt assembly’
- Valid “assemble to order automation” (for assemblies requires AAX License)
- Can create many different configurations of ‘similar’ designs
- Easy to use and learn
- Tables keep growing, system slows down over time
- Data management of all files can be a challenge
- Files are linked and changes are limited as usage is increased
- Must create all files ahead of time for top down design automation
- Must create every possible scenario ahead of time
- Values in tables may conflict with values in relations
Wizard Based Templates
Wizard Template Functionalities
- Create variants of: Dimension, Feature, Merge Part, Component, Parameter, Ref Model, Group, Pattern Table and much more
- Stores standard CAD information in a ‘template’ file (start part files) and logic in SQL DB
- Configured models are all copied from template, modified and then saved as a normal file
- Valid for “engineer to order”, “configure to order” and “assemble to order” (No AAX required, just foundation license)
- Can create unlimited configurations of very ‘different’ designs
- Easy to use and learn
- Can reroute & replace ‘unrelated’ features and components easily
- Files are easily managed by data management system
- Create new files ‘on the fly’
- Faster product design
- Requires additional 3rd party software to create the logic and run the automation
Within PDM Link, family tables and nested family tables can be successfully converted to standard parts using RuleSoft utility tool called Parts Cleanser.
This tool can take instances and nested instances (tables where there’s an instance that has its own table) and extract them and convert them to regular non instances inside of common space. This will create a new iteration of the part number and old version will be an ‘instance’ but the new version is completely on its own and has no relationship to the original generic file and it’s family table.
To further develop the implementation, secret hidden config.pro option for Creo Parametric is a config option related to this that might help:
The secret option will prevent Creo Parametric from failing as it tries to retrieve an assembly where the old instance was used and now is not an instance.
For future design, it is recommended that Shaw Development changes their practices of Creo product design and move to a script based ETO/CTO system that doesn’t generate ‘instances’ but stand along parts as the end deliverable.
In order to do this we generally require onsite scoping days to evaluate the complexity of the designs in order to propose the level of effort this would take.