*PolyBeam()

Creates a polybeam.

Syntax

*PolyBeam(beam_name,"beam_label",pt_1,pt_2,,pt_n)

Arguments

beam_name: The variable name of the polybeam.; Data type: varname
beam_label: The descriptive label of the polybeam.; Data type: label
pt_1, pt_2, ..., pt_n: The points that describe the polybeam; Data type: Point

Example

*Point(pt_1, "Point 1")
*Point(pt_2, "Point 2")
*Point(pt_3, "Point 3")
*Point(pt_4, "Point 4")

*PolyBeam(pb_stabar, "Stab bar", pt_1, pt_2, pt_3, pt_4)

Context

*BeginMdl()

*DefineAnalysis()

*DefineSystem()

Properties

Table 1.
Property	Returns Data Type	Description
beam@pt_1	Beam	The beam on the polybeam originating at pt_1.
body@pt_1	Body	The dummy body on the beam at pt_1.
label	string	The descriptive label of the polybeam.
state	boolean	Control state (TRUE or FALSE).
varname	string	The variable name of the polybeam.
Rho	real	The density of the polybeam.
E	real	The Young's modulus of elasticity.
G	real	The shear modulus of elasticity.
OD	real	The outer diameter of the polybeam cross section.
ID	real	The inner diameter of the polybeam cross section.
AS	real	The correction factor for the shear deflection.
CRATIO		This argument indicates the structural damping matrix is a ratio of the stiffness matrix.

Comments

A polybeam is modeled as a number of beam segments connecting intermediate bodies created internally by MotionView. The mass and inertia properties of the polybeam are modeled as lumped mass and inertias of intermediate bodies.

The intermediate bodies created for a polybeam can be accessed by specifying one of the point locations used to define the polybeam. For example, the body located at pt_3 in pb_stabar can be accessed as pb_stabar.body@pt_3. Similarly the beam segments of a polybeam may be accessed by specifying the point from where it originates. For example, the beam between pt_2 and pt_3 can be accessed as pb_stabar.beam@pt_2.