Markers

A marker is an orthonormal, right-handed coordinate system and reference frame. It is a fundamental entity in a multibody system and is used by the solver to represent all system components.

The multibody solver in Inspire (MotionSolve) uses markers to define entities such as joints, bushings, and inertial reference frames. When such entities are created, they include built-in markers known as implicit markers. In addition, markers can be explicitly created and used as reference frames in entities such as forces, outputs, or within solver functions.

Every marker must be associated with a rigid or flexible part, a concentrated mass, or the ground.

Note: A global frame marker, associated with the ground (the Newtonian reference frame) and located at the global origin, is available by default.

Markers can be defined as a pair entity, which helps in creating models that have identical entities across the x-z plane. The pair entity can have asymmetric or symmetric properties. When symmetric, the properties from one side are mirrored to the other side about the x-z plane.

Add a Marker

To add a marker, define the origin by selecting a hard point, a snap point on a part, or an edge on a part. Then define the orientation by using hard points, snap points or edges on a part, or entering Euler angles.

On the Motion ribbon, under Profile, select Analyst.
Under Create, select the Markers tool.

Tip: To find and open a tool, press Ctrl+F. For more information, see Find and Search for Tools.

The guide panel is displayed.
Figure 1.
Optional: To select a Parent system, click Advanced selector ....
Optional: Edit the Label.
Optional: To create a pair of entities, turn on Pair.
- To create a model that is symmetric about the x-z plane, in the Property Editor, under General, set Symmetry to Left or Right.
- To create a model that is asymmetric, set Symmetry to None.
Resolve the Part collector by clicking a part in the modeling window or by using the Advanced selector ....
The selected body should now be highlighted in red.
Select a hard point as the origin:
- To select an existing hard point, you do one of the following:
  - In the modeling window, select the hard point.
  - Click Advanced selector ..., and then select a point in the Model Tree.
- To create a new hard point, select a vertex, midpoint, edge or face on a part. When an edge or face is selected, the point is created at the center of the edge or face.
- To select the global origin, click Ground .
Click Apply .
The entity appears in the Model Browser and its properties appear in the Property Editor.
Right-click and mouse through the check mark to exit, or double-right-click.

Edit a Marker

Edit a marker using the Markers tool or Property Editor.

Select the marker.

Choose from the following methods:

Table 1.
To use this method	Do this
Markers tool	On the Motion ribbon, under Profile, select Analyst. Under Create, select the Markers tool. The marker is highlighted, and a guide panel appears. Figure 2. To edit the part and origin, follow the steps in the Add a Marker section. Select the references or rotation angles to translate or rotate the marker: If Orient One Axis is selected, use the axis collector to choose the x-, y-, or z-axis as the reference. You can use the down arrow to select the desired axis. Then, select a hard point, vector, or vertex, midpoint, edge, or face on the part to orient the axis. If Orient Two Axes is selected, in addition to the first reference axis, use the second collector to select a reference plane. Use the down arrow to choose the desired plane. Then, select a hard point, vector, or vertex, midpoint, edge, or face on the part to orient the plane. If Rotation Angles is selected, enter the Euler angles to apply the desired rotation to the system. Right-click and mouse through the check mark to exit, or double-right-click.
Property Editor	From the View menu, select Property Editor. The selected marker's properties are listed in the Property Editor and can be edited. Refer to Marker Properties.

Marker Properties

Descriptions of marker properties in the Property Editor.

Table 2.
Property Name	Description
General
Name	Name of the entity
Variable Name	The variable name, a unique identifier string of the entity
ID	A unique identifying integer
Part	The parent part to which the marker belongs
Origin	Location where the marker is applied
Floating	Allows the marker to move in respect to the parent part
Symmetry	To make the entity symmetric about the x-z plane, set Symmetry to LEFT or RIGHT. The side on the positive y-axis is considered the RIGHT side and will act as the leader if selected. The opposite side will follow. To make the entity asymmetric, set Symmetry to NONE.
Orientation
Method (Orientation)	Method of orientation. The following choices are available:
Orient two axes	Orient the marker using the “Axis-Plane” method. Provide a direction for an axis and another direction that lies in a plane defined by the 1^st axis and 2^nd axis.
Orient one axis	Orient the marker using the “One Axis” method. Provide a direction for an axis. The other axes are automatically oriented.
Orient by angles	Orient the marker using Euler angles
Direction	Select a direction – X \| Y \| Z axis.
Method (Direction)	Select a method for aligning the chosen axis along a direction – Point \| Vector \| DxDyDz.
Point	Pick a point in the graphic screen or through the Advanced selector when Method (Direction) is Point.
Vector	Pick a vector through the graphic screen or through the Advanced Selector when Method (Direction) is Vector.
Z \| X' \| Z ''	Provide the Euler Angles when Method (Orientation) is Orient by angles.
Reference	The reference frame (Marker) for applying the Euler Angles when Method (Orientation) is Orient by angles.
FlexBody Connection
Override	This overrides automatic connection radius. This is applicable when the marker is applied on a flex body.
Connection Radius	This overrides search distance to connect the entity with rigid elements when the marker is applied on a flex body. Refer to Connection Radius for more details.