Mass element with fixed inertial properties
Simscape / Multibody / Body Elements
The Inertia block adds to the attached frame a point or distributed
mass with fixed inertial properties. The type of mass (point or distributed) depends on
the parameterization selected for the block. A selection of
Mass assumes the mass to be concentrated at a point and therefore
devoid of rotational inertia. A selection of
the mass to be distributed in space, allowing it to possess nonzero moments of inertia,
products of inertia, and center-of-mass coordinates (the latter against the reference
frame of the block).
A choice of marker provides a means to identify the inertia in the model
visualization. The visualization opens (by default) in Mechanics Explorer at the start
of simulation or upon diagram update. Use the marker to track the motion of the inertia
against the remainder of the model. Various marker shapes are available—an inertia icon,
a sphere, a cube, a frame—each with configurable dimensions. To eliminate the inertia
from the model visualization (while retaining its effects on the model dynamics), the
block provides an option of
R — Reference frame
Local reference frame of the inertia element. Connect to a frame line or frame port to define the relative position and orientation of the inertia.
Type — Inertia parameterization to use
Point Mass (default) |
Inertia parameterization to use. Select
Mass to represent a mass with no rotational inertia.
Custom to represent a distributed mass
with rotational inertia.
Type — Graphic to use in the visualization of the inertia
Marker (default) |
Choice of graphic to use in the visualization of the inertia. The graphic
is by default a simple marker, specifically an inertia icon. Other markers
are available, these encompassing spheres, cubes, and frames. Change this
None to eliminate the inertia
altogether from the model visualization.
Marker: Shape — Shape of the marker to assign to the inertia
Inertia Icon (default) |
Shape of the marker by means of which to visualize the inertia. The motion of the marker reflects the motion of the inertia itself.
Marker: Size — Width of the marker in pixels
10 (default) | scalar with units of pixels
Width of the marker in pixels. This width does not scale with zoom level. Note that the apparent size of the marker depends partly on screen resolution, with higher resolutions packing more pixels per unit length, and therefore producing smaller icons.