Product Factors that Shape Cost Impact¶

Cost impact for upgrades to aPriori Professional 2023 R1 SP1.

There are three main areas of functionality that help generate costs in aPriori:

Geometry extraction: analyzes CAD models and generates Geometric Cost Drivers which are inputs to costing.
Cost engine: interprets the cost model intent and design to produce a cost.
Cost models: specify the rules and formulas that generate cycle times and costs from geometry and Digital Factory inputs.

In each new release, aPriori introduces enhancements and bug fixes in the form of changes to one or more of these areas. How a change affects your upgrade procedure depends on which area was changed:

Cost Model Changes generally do not require immediate validation or calibration, because you can choose not to immediately incorporate cost model changes when you upgrade. By default, cost model changes do not affect costings performed with configured Digital Factories until you explicitly increment the Digital Factories’ cost model versions. See Cost Model Changes for more information.
Geometry and Cost Engine Changes, in contrast, do affect costings performed with configured Digital Factories by default, but note the following:
- These changes improve costing accuracy and robustness.
- Some changes cause cost estimates to change only by a small amount or apply only to a narrow class of parts.
- Changes rated Low or Medium impact (see Change Summary Tables) are generally small enough to accept without re-validation.
- You can disable many of these changes with a site variable setting.

For changes rated High impact, you must decide whether to accept, validate, or disable the change. See Geometry and Cost Engine Changes for more information.

Cost Model Changes¶

Cost models are versioned, and each has an associated cost model version number. Every baseline or configured Digital Factory declares an active cost model version for each process group. When you upgrade to a new release of aPriori, the baseline Digital Factories use the newest cost model versions (containing the latest enhancements), but your configured Digital Factories continue to use the cost model versions they used with the previous release, unless and until you explicitly change the Digital Factories’ declared cost model versions.

Once a particular cost model version is released, it is not modified in subsequent releases, except very rarely for back-ported bug fixes. aPriori always maintains backwards compatibility with every cost model version that has ever shipped. This insulates configured Digital Factories from the impact of cost model changes.

Therefore, you generally can upgrade to the new aPriori release without immediately validating or calibrating the new cost models. Your configured Digital Factories will simply retain the earlier cost model versions, and you can subsequently validate new cost model versions in your own timeframe if you would like to incorporate them into your configured Digital Factory.

Geometry and Cost Engine Changes¶

In contrast to Cost Model Changes, geometry and cost engine code changes are not versioned, so when you upgrade to a new release of aPriori, you always receive code changes in these areas, regardless of the cost model versions in use. Such changes might impact cost results even with earlier cost model versions, but they improve costing accuracy and robustness.

Note also that, although geometry and cost engine changes are not strictly speaking versioned, you can disable many of them with a site variable setting, allowing you to retain the legacy behavior when you do not want to immediately validate or accept the new behavior.

Before you upgrade, review the process groups you use, and identify the ones that have changes with cost impact (see Change Summary Tables). Note that changes vary as to the size of the cost-estimate change they cause. Note also that some changes affect only certain classes of parts. For example, a bug fix typically affects only parts that exhibit specific geometries that triggered the bug.

For changes rated High impact, you must decide whether to accept, validate, or disable the change. you have the following choices:

Accept the changes without revalidating.
Disable the changes (by setting one or more site variables). (This option is available for some but not necessarily all geometry and cost engine changes.)
Re-validate costing results before accepting the changes.

Once you have decided whether to accept or disable each High-impact geometry or cost engine change for the process groups that you use, you can upgrade to the new release. If there are no High-impact geometry or cost engine changes, you can upgrade to the new release without validation.

aPriori also recommends that you review the cost model changes as well as the Low- and Medium-impact geometry and cost engine changes for the process groups you use.