part modify point_mass mass_properties
Allows you to modify mass properties on an existing point_mass.
Format:
part modify point_mass mass_properties |
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point_mass_name = | an existing part |
mass = | mass |
center_of_mass_marker = | an existing marker |
material_type = | an existing material |
density = | density |
Example:
part modify point_mass mass_properties & |
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point_mass_name = | piston & |
mass = | 1.85 & |
center_of_mass_marker = | marker__1 & |
material_type = | steel |
Description:
Parameter | Value Type | Description |
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point_mass_name | An Existing Point_Mass | Specifies the point_mass to be modified. You use this parameter to identify the existing point_mass to be affected with this command. |
mass | Mass | Specifies the part mass |
center_of_mass_marker | An Existing Marker | Specifies the marker that defines the part center of mass and, in the absence of the inertia marker, the axes for the inertia properties. |
material_type | An Existing Material | Specifies the part material_type and that the mass properties of the part are to be automatically calculated |
density | Density | Specifies the part density and that the mass properties of the part are to be automatically calculated. |
Extended Definition:
1. The mass properties of a point_mass include the mass and the center-of-mass marker.
You may assign zero mass to a point_mass whose three degrees of motion you constrain with respect to bodies that do have mass. However, due to the number of changes that you may make to the data set in the course of defining a model, the probability of a later change requiring that the point_mass have mass is high. Consequently, you are encouraged to assign finite (although insignificant) masses and inertias to point_mass you would otherwise give zero mass properties.
If you specify the mass for a point_mass, you must also specify the center-of-mass marker for the point_mass.
You may identify a point_mass by typing its name or by picking it from the screen.
If the point_mass is not visible on the screen, you must type the name. You may also find it convenient to type the name even if the point_mass is displayed.
If you created the point_mass by reading an Adams data set or graphics file, the point_mass name is the letters POI followed by the Adams data set point_mass ID number. For example, the name of Adams POINT_MASS/101 is POI101. If you created the point_mass during preprocessing, you will have given it a name at that time.
If a point_mass is available by default, you may identify it by entering only its name. If it is not, you must enter its full name.
To identify a point_mass under another model, for instance, you may need to enter the model name as well. For example, you may specify point_mass 'arm' from model 'robot' by entering ".robot.arm". If you type a "?", Adams View will list the point_masss available by default.
You must separate multiple point_mass names by commas.
If the point_mass is visible in one of your views, you may identify it by picking on any of the graphics associated with it.
You need not separate multiple point_mass picks by commas.
2. If the point_mass has no mass, Adams uses the point_mass LPRF to represent the position of the point_mass internally. If the point_mass has mass, Adams uses the position of the center-of-mass marker to represent the translational position of the point_mass internally.The orientation of the point_mass and the center-of-mass marker have no effect on the simulation.
3. If the point_mass has mass, Adams uses the position of the center-of-mass (CM) marker to represent the translational position of the point_mass internally.