Defining requirements

Requirements define stiffness and strength targets.

The minimum factor of safety and maximum part deflection are the two requirements that must be defined for an Optimization. These requirements act as targets for the Optimization algorithms and effect the part stiffness and strength. The default values are shown below.

requirements

Details for requirements:

  • The factor of safety is a strength-based metric that indicates how close the part is to yielding. The value reported back to the user is the minimum value across all regions in the part. It is best thought of as a factor on the loads defined in the use case. A few examples will clarify what the factor of safety is. Imagine a part that has a surface where a 50 N load is applied:

    • A factor of safety = 1 means that a region in the part will begin to yield when the load = 50 N.

    • A factor of safety = 2 means that a region in the part will begin to yield when the load = 100 N.

    • A factor of safety = 0.1 means a region in the part will begin to yield when the load = 5 N.

  • The deflection (aka displacement) is a metric for the part stiffness and is computed by Smart Slice. The value reported back to the user is the maximum deflection of any point on the part. The units for displacement are millimeter (mm).

  • Requirements do not influence the results from a Validation. During a Validation, the minimum factor of safety and maximum deflection are computed for the current print settings. As shown in the example below, the computed values are compared to the target values in the results that appear upon completion of the Validation.

ss_environment_2

As an example, consider the following requirements:

  • Factor of Safety >= 2.

  • Max Deflection <= 6.5 mm.

In this scenario, the user is telling Smart Slice to optimize the print settings so that the part has a factor of safety that is greater than or equal to 2 and a maximum deflection of 6.5 mm or less. These 2 requirements are used to define the targets for part stiffness and part strength.