WOLFRAM SYSTEMMODELER

PointMass

Body used at all places of the comparison model with zero inertia tensor

Wolfram Language

In[1]:=
Click for copyable input
SystemModel["Modelica.Mechanics.MultiBody.Examples.Elementary.PointGravityWithPointMasses2.SystemWithStandardBodies.PointMass"]
Out[1]:=

Information

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

Body used at all places of the comparison model with zero inertia tensor (and mass = 1 kg and a red color).

Connectors (1)

frame_a

Type: Frame_a

Description: Coordinate system fixed at body

Parameters (26)

animation

Value: true

Type: Boolean

Description: = true, if animation shall be enabled (show cylinder and sphere)

r_CM

Value:

Type: Position[3] (m)

Description: Vector from frame_a to center of mass, resolved in frame_a

m

Value: 1

Type: Mass (kg)

Description: Mass of rigid body

I_11

Value: 0

Type: Inertia (kg·m²)

Description: (1,1) element of inertia tensor

I_22

Value: 0

Type: Inertia (kg·m²)

Description: (2,2) element of inertia tensor

I_33

Value: 0

Type: Inertia (kg·m²)

Description: (3,3) element of inertia tensor

I_21

Value: 0

Type: Inertia (kg·m²)

Description: (2,1) element of inertia tensor

I_31

Value: 0

Type: Inertia (kg·m²)

Description: (3,1) element of inertia tensor

I_32

Value: 0

Type: Inertia (kg·m²)

Description: (3,2) element 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 frame_a around 'sequence_start' axes into frame_b

sequence_start

Value: {1, 2, 3}

Type: RotationSequence

Description: Sequence of rotations to rotate frame_a into frame_b 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)

sphereDiameter

Value: world.defaultBodyDiameter

Type: Diameter (m)

Description: Diameter of sphere

cylinderDiameter

Value: sphereDiameter / Types.Defaults.BodyCylinderDiameterFraction

Type: Diameter (m)

Description: Diameter of cylinder

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

I

Value: [I_11, I_21, I_31; I_21, I_22, I_32; I_31, I_32, I_33]

Type: Inertia[3,3] (kg·m²)

Description: inertia tensor

R_start

Value: Modelica.Mechanics.MultiBody.Frames.axesRotations(sequence_start, angles_start, zeros(3))

Type: Orientation

Description: Orientation object from world frame to frame_a at initial time

z_a_start

Value: Frames.resolve2(R_start, z_0_start)

Type: AngularAcceleration[3] (rad/s²)

Description: Initial values of angular acceleration z_a = der(w_a), i.e., time derivative of angular velocity resolved in frame_a

Q_start

Value: Frames.to_Q(R_start)

Type: Orientation

Description: Quaternion orientation object from world frame to frame_a at initial time

phi_start

Value: if sequence_start[1] == sequence_angleStates[1] and sequence_start[2] == sequence_angleStates[2] and sequence_start[3] == sequence_angleStates[3] then angles_start else Frames.axesRotationsAngles(R_start, sequence_angleStates)

Type: Angle[3] (rad)

Description: Potential angle states at initial time

Components (4)

R_start

Type: Orientation

Description: Orientation object from world frame to frame_a at initial time

world

Type: World

Description:

cylinder

Type: Shape

Description:

sphere

Type: Shape

Description:

Used in Examples (1)

SystemWithStandardBodies

For comparison purposes, an equivalent model with Bodies instead of PointMasses