Manual

When selecting the Manual option on the Concentrated Mass form, the following sections are available:

• Coordinate System: This allows you to select a coordinate system used for Inertia and Offset definitions.
• Selected Entities: Selection box for you to select vertex points.
• Mass: Input box where you can define the mass value.
• Display Options: Allows you to edit the display options of the concentrated mass.
  • Size: Changes the size of the concentrated mass.
  • Color: Allows you to pick the color of the concentrated mass.
• Add To Analysis: This checkbox automatically puts this concentrated mass under Analysis\Idealizations.
• Inertia:
  • You can define the mass moments of inertia here.
  • The form of the inertia matrix about its center of gravity is taken as:

    

    where:

    

• Offset:
  • You can offset the mass defined at vertices from their center of gravity (CG).
  • If a coordinate system is selected, then X1, X2, X3 are defined by a local Cartesian system similar to the method in which displacement coordinate systems are defined.