PartsRigid components such as bodies with mass and inertia and massless rods 
Frame fixed in the world frame at a given position 

Fixed translation of frame_b with respect to frame_a 

Fixed translation followed by a fixed rotation of frame_b with respect to frame_a 

Rigid body with mass, inertia tensor and one frame connector (12 potential states) 

Rigid body with mass, inertia tensor, different shapes for animation, and two frame connectors (12 potential states) 

Rigid body with box shape. Mass and animation properties are computed from box data and density (12 potential states) 

Rigid body with cylinder shape. Mass and animation properties are computed from cylinder data and density (12 potential states) 

Rigid body where body rotation and inertia tensor is neglected (6 potential states) 

Propagate 1dim. support torque to 3dim. system (provided world.driveTrainMechanics3D=true) 

1D inertia attachable on 3dim. bodies (3D dynamic effects are taken into account if world.driveTrainMechanics3D=true) 

1D gearbox with arbitrary shaft directions and 3dim. bearing frame (3D dynamic effects are taken into account provided world.driveTrainMechanics3D=true) 

Ideal rolling wheel on flat surface z=0 (5 positional, 3 velocity degrees of freedom) 

Ideal rolling wheel set consisting of two ideal rolling wheels connected together by an axis 
This information is part of the Modelica Standard Library maintained by the Modelica Association.
Package Parts contains rigid components of a multibody system. These components may be used to build up more complicated structures. For example, a part may be built up of a "Body" and of several "FixedTranslation" components.
Model  Description 

Fixed  Frame fixed in world frame at a given position.
It is visualized with a shape, see shapeType below
(the frames on the two
sides do not belong to the component): 
FixedTranslation  Fixed translation of frame_b with respect to frame_a.
It is visualized with a shape, see shapeType below
(the frames on the two sides do not belong to the component): 
FixedRotation  Fixed translation and fixed rotation of frame_b with respect to frame_a
It is visualized with a shape, see shapeType below
(the frames on the two sides do not belong to the component): 
Body  Rigid body with mass, inertia tensor and one frame connector.
It is visualized with a cylinder and a sphere at the
center of mass: 
BodyShape  Rigid body with mass, inertia tensor, different shapes
(see shapeType below)
for animation, and two frame connectors: 
Fixed BodyBox  Rigid body with box shape (mass and animation properties are computed
from box data and from density): 
BodyCylinder  Rigid body with cylinder shape (mass and animation properties
are computed from cylinder data and from density): 
PointMass  Rigid body where inertia tensor and rotation is neglected: 
Mounting1D  Propagate 1dim. support torque to 3dim. system 
Rotor1D  1D inertia attachable on 3dim. bodies (without neglecting dynamic effects) 
BevelGear1D  1D gearbox with arbitrary shaft directions (3D bearing frame) 
Components Fixed, FixedTranslation, FixedRotation
and BodyShape are visualized according to parameter
shapeType, that may have the following values (e.g., shapeType = "box"):
All the details of the visualization shape parameters are given in Visualizers.FixedShape
Colors in all animation parts are defined via parameter color. This is an Integer vector with 3 elements, {r, g, b}, and specifies the color of the shape. {r,g,b} are the "red", "green" and "blue" color parts, given in the ranges 0 .. 255, respectively. The predefined type MultiBody.Types.Color contains a menu definition of the colors used in the MultiBody library (this will be replaced by a color editor).