Free Motion - MapleSim Help

Online Help

All Products    Maple    MapleSim


Home : Support : Online Help : MapleSim : MapleSim Component Library : Multibody : Joints and Motions : componentLibrary/multibody/jointsAndMotions/FreeMotion

Free Motion

Joint allowing three translational and three rotational degrees of freedom

 

Description

Connections

Parameters

See Also

Description

A free joint, sometimes called a 6-DOF joint or motion sensor, is shown in the diagram below with two reference frames at either end of the connection: x1y1z1on body 1, and x2y2z2 on body 2.  The free joint places no restrictions on the relative motion of the two frames, but simply provides a means for measuring the relative translations and rotations. The translation of the end frame, x2y2z2,relative to the start frame, x1y1z1,is represented by the vector, r , which is resolved into its three components in the x1y1z1 frame. The rotation of x2y2z2,relative to x1y1z1, is represented by three Euler angles.

Connections

Name

Description

framea

Joint inboard frame

frameb

Joint outboard frame

Parameters

Symbol

Default

Units

Description

Modelica ID

Typev

Inboard

-

Indicates whether the initial velocity is expressed in the inboard or outboard frame

VelType

Typeθ

1,2, 3

-

Indicates the sequence of body-fixed rotations used to describe the initial orientation of the joint.  For example, 1,2,3 refers to sequential rotations about the x, then y, then z axis (123 - Euler angles)

RotType

Typeω

Euler

-

Indicates whether the initial angular velocity is expressed in the inboard or outboard frame. If Euler is selected, the initial angular velocities are assumed to be the direct derivatives of the Euler angles.

AngVelType

ICr,v

Ignore

-

Indicates whether MapleSim ignores, tries to enforce, or strictly enforces the translational initial conditions

MechTranTree

r&conjugate0;0

0,0,0

m

Initial displacement of the joint at the start of the simulation, expressed along the x-, y-, and z-axis of the inboard frame respectively

InitPos

v&conjugate0;0

0,0,0

ms

Initial velocity of the joint at the start of the simulation, expressed along the x-, y-, and z-axis of the inboard frame respectively

InitVel

ICθ,ω

Ignore

-

Indicates whether MapleSim ignores, tries to enforce, or strictly enforces the rotational initial conditions

MechRotTree

θ&conjugate0;0

0,0, 0

rad

Initial rotation of the joint at the start of the simulation, based on the Typeθ parameter value

InitAng

ω&conjugate0;0

0,0, 0

rads

Initial velocity of the joint at the start of the simulation, based on the Typeω parameter value

InitAngVel

See Also

Joints and Motions

Multibody Overview