BodyShape

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

Diagram

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Rigid body with mass and inertia tensor and two frame connectors. All parameter vectors have to be resolved in frame_a. The inertia tensor has to be defined with respect to a coordinate system that is parallel to frame_a with the origin at the center of mass of the body. The coordinate system frame_b is always parallel to frame_a.

By default, this component is visualized by any shape that can be defined with Modelica.Mechanics.MultiBody.Visualizers.FixedShape. This shape is placed between frame_a and frame_b (default: length(shape) = Frames.length(r)). Additionally a sphere may be visualized that has its center at the center of mass. Note, that the animation may be switched off via parameter animation = false.

Parts.BodyShape

The following shapes can be defined via parameter shapeType, e.g., shapeType="cone":

Visualizers.FixedShape

A BodyShape component has potential states. For details of these states and of the "Advanced" menu parameters, see model MultiBody.Parts.Body.

Parameters (30)

animation	Value: true Type: Boolean Description: = true, if animation shall be enabled (show shape between frame_a and frame_b and optionally a sphere at the center of mass)
animateSphere	Value: true Type: Boolean Description: = true, if mass shall be animated as sphere provided animation=true
r	Value: Type: Position[3] (m) Description: Vector from frame_a to frame_b resolved in frame_a
r_CM	Value: Type: Position[3] (m) Description: Vector from frame_a to center of mass, resolved in frame_a
m	Value: Type: Mass (kg) Description: Mass of rigid body
I_11	Value: 0.001 Type: Inertia (kg·m²) Description: Element (1,1) of inertia tensor
I_22	Value: 0.001 Type: Inertia (kg·m²) Description: Element (2,2) of inertia tensor
I_33	Value: 0.001 Type: Inertia (kg·m²) Description: Element (3,3) of inertia tensor
I_21	Value: 0 Type: Inertia (kg·m²) Description: Element (2,1) of inertia tensor
I_31	Value: 0 Type: Inertia (kg·m²) Description: Element (3,1) of inertia tensor
I_32	Value: 0 Type: Inertia (kg·m²) Description: Element (3,2) of inertia tensor
angles_fixed	Value: false Type: Boolean Description: = true, if angles_start are used as initial values, else as guess values
angles_start	Value: {0, 0, 0} Type: Angle[3] (rad) Description: Initial values of angles to rotate world frame around 'sequence_start' axes into frame_a
sequence_start	Value: {1, 2, 3} Type: RotationSequence Description: Sequence of rotations to rotate world frame into frame_a at initial time
w_0_fixed	Value: false Type: Boolean Description: = true, if w_0_start are used as initial values, else as guess values
w_0_start	Value: {0, 0, 0} Type: AngularVelocity[3] (rad/s) Description: Initial or guess values of angular velocity of frame_a resolved in world frame
z_0_fixed	Value: false Type: Boolean Description: = true, if z_0_start are used as initial values, else as guess values
z_0_start	Value: {0, 0, 0} Type: AngularAcceleration[3] (rad/s²) Description: Initial values of angular acceleration z_0 = der(w_0)
shapeType	Value: "cylinder" Type: ShapeType Description: Type of shape
r_shape	Value: {0, 0, 0} Type: Position[3] (m) Description: Vector from frame_a to shape origin, resolved in frame_a
lengthDirection	Value: to_unit1(r - r_shape) Type: Axis Description: Vector in length direction of shape, resolved in frame_a
widthDirection	Value: {0, 1, 0} Type: Axis Description: Vector in width direction of shape, resolved in frame_a
length	Value: Modelica.Math.Vectors.length(r - r_shape) Type: Length (m) Description: Length of shape
width	Value: length / world.defaultWidthFraction Type: Distance (m) Description: Width of shape
height	Value: width Type: Distance (m) Description: Height of shape
extra	Value: 0.0 Type: ShapeExtra Description: Additional parameter depending on shapeType (see docu of Visualizers.Advanced.Shape)
sphereDiameter	Value: 2 * width Type: Diameter (m) Description: Diameter of sphere
enforceStates	Value: false Type: Boolean Description: = true, if absolute variables of body object shall be used as states (StateSelect.always)
useQuaternions	Value: true Type: Boolean Description: = true, if quaternions shall be used as potential states otherwise use 3 angles as potential states
sequence_angleStates	Value: {1, 2, 3} Type: RotationSequence Description: Sequence of rotations to rotate world frame into frame_a around the 3 angles used as potential states

Inputs (3)

color	Default Value: Modelica.Mechanics.MultiBody.Types.Defaults.BodyColor Type: Color Description: Color of shape
sphereColor	Default Value: color Type: Color Description: Color of sphere of mass
specularCoefficient	Default Value: world.defaultSpecularCoefficient Type: SpecularCoefficient Description: Reflection of ambient light (= 0: light is completely absorbed)

color

Default Value: Modelica.Mechanics.MultiBody.Types.Defaults.BodyColor

Type: Color

Description: Color of shape

sphereColor

Default Value: color

Type: Color

Description: Color of sphere of mass

specularCoefficient

Default Value: world.defaultSpecularCoefficient

Type: SpecularCoefficient

Description: Reflection of ambient light (= 0: light is completely absorbed)

Connectors (2)

	frame_a	Type: Frame_a Description: Coordinate system fixed to the component with one cut-force and cut-torque
	frame_b	Type: Frame_b Description: Coordinate system fixed to the component with one cut-force and cut-torque

frame_a

Type: Frame_a

Description: Coordinate system fixed to the component with one cut-force and cut-torque

frame_b

Type: Frame_b

Description: Coordinate system fixed to the component with one cut-force and cut-torque

Components (5)

	frameTranslation	Type: FixedTranslation
	body	Type: Body
	world	Type: World
	shape1	Type: Shape
	shape2	Type: Shape

Used in Examples (8)

	FreeBody Modelica.Mechanics.MultiBody.Examples.Elementary Free flying body attached by two springs to environment
	InitSpringConstant Modelica.Mechanics.MultiBody.Examples.Elementary Determine spring constant such that system is in steady state at given position
	ActuatedDrive Modelica.Mechanics.MultiBody.Examples.Rotational3DEffects Demonstrates usage of models Rotor1D and Mounting1D
	MovingActuatedDrive Modelica.Mechanics.MultiBody.Examples.Rotational3DEffects Demonstrates usage of model Rotor1D mounted on a moving body
	PrismaticConstraint Modelica.Mechanics.MultiBody.Examples.Constraints Body attached by one spring and two prismatic joints or constrained to environment
	RevoluteConstraint Modelica.Mechanics.MultiBody.Examples.Constraints Body attached by one spring and revolute joint or constrained to environment
	SphericalConstraint Modelica.Mechanics.MultiBody.Examples.Constraints Body attached by one spring and spherical joint or constrained to environment
	UniversalConstraint Modelica.Mechanics.MultiBody.Examples.Constraints Body attached by one spring and universal joint or constrained to environment