Step 1.5: Add and Edit a Motion-Dimension FB

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Step 1.5: Add and Edit a Motion-Dimension FB

Objective of Step 1.5:

To learn:

•about the two kinematic-states of a Parts : kinematically-defined or not kinematically-defined.

•that Parts must be kinematically-defined before we can analyze their motions.

•that Part-Outlines have two colors to show you its kinematic-state.

•how to add a Motion-Dimension FB to control the angle of the Part relative to a Line.

•that a Motion-Dimension FB (Function-Block) changes the kinematic state of a Part.

To explore the elements in the Kinematic-Tree.

Video

Tutorial 1 STEP 1.5: Add Motion-Dimension FB

IMPORTANT

A Part has two kinematic states.

Either

... a Part is not kinematically-defined

OR

... a Part is kinematically-defined

We want all Parts in the model to be kinematically-defined.

When a Part is kinematically-defined, the Part has a Mobility = 0. . We review Mobility in a later Tutorial.

Kinematic State of the Parts after STEP 1.4, and before we do STEP 1.5

The Base-Part is kinematically-defined.

The Part (you have added to the model) is not kinematically-defined.

The Part-Outline of the Base-Part and the Part have different colors to show you they have different kinematic states.

The color of the Base-Part is (approximately) green.

The color of the Part is (approximately) blue.
btn_delkeywordAdd a Motion-Dimension FB to the Part

You can drag the Part-Outline (and Part) around the Pin-Joint. The Part has one Degrees-of-Freedom.

AAdd Motion-Dimension FB

AAdd Motion-Dimension FB

 

STEP 1: Start the Add Motion-Dimension FB command

GST-Icon-FB-MotionDimension

1.Expand the Kinematic FB toolbar - it is to the right of the graphics-area (>>>)

2.Click Add Motion-Dimension FB Red-14-1b

The Command-Manager starts.

GST-1-5-3

The Command-Manager has three selection boxes.

The element-types you can click to fill the selection-boxes are:

Box Red-14-2 - a Joint (a Pin-Joint or Slide-Joint)

Box Red-14-3 - a Solved Line or Point*

Box Red-14-4 - an Unsolved Line or Point**

* Solved Line or Point = a Line (for a Pin-Joint) or a Point (for a Slide-Joint) in a Part that is kinematically-defined

** Unsolved Line or Point = a Line (for a Pin-Joint) or a Point (for a Slide-Joint) in a Part that is not kinematically-defined

STEP 2: Select the three elements to Add Motion-Dimension FB

Red-14-2 Click the Pin-Joint - see STEP 1.4

Red-14-3 Click the Line that is in the Base-Part - the Base-Part is kinematically-defined.

Red-14-4 Click the CAD-Line that is in the Part - the Part is NOT kinematically-defined.

GST-1-5-2
Commandd Manager with selections

Commandd Manager with selections

STEP 3: Complete the command

Click OK-tiny-15-18 in the Command-Manager

OR

Right-Click in the graphics-area

 

GST-1-5-4

Result

The Motion-Dimension FBRed-14-1b and the Motion-DimensionRed-14-2 are now in the graphics-area.

The Base-Part and the Part are now kinematically-defined.

The color of the Part-Outline of the Part has changed, typically from Blue to Green.

Note: The Motion-Dimension FB element has two features. There is the:

Red-14-1b Function-Block

Red-14-2 Motion-Dimension

btn_delkeywordEdit the Motion-Dimension FB

Edit the Base-Value parameter in the Motion-Dimension dialog.

The Base-Value is an offset value of the angle
Motion-Dimension FB dialog

Motion-Dimension FB dialog

STEP 1: Open the Motion-Dimension dialog

1.Double-click the Motion-Dimension FB in the graphics-area

or

2.See How to open a dialog.

The Motion-Dimension dialog is now open.

In the Motion-Dimension dialog >  Base and Motion Angle 

STEP 2: Edit the Parameters

Red-14-1b Base-Value

The angle of the Rocker when a wire is not connected to the input-connector of the Motion-Dimension FB (or when the motion-value at the input is zero)

or

Red-14-3 Base-Value + Motion Value

The angle of the Rocker when a wire is connected to the input-connector of the Motion-Dimension FB.

Directions

It is possible to negate the Base-Value and the Motion-Value.

 
btn_delkeywordHow to move the Motion-Dimension FB and move the Motion-Dimension Line

In the graphics-area, the Motion-Dimension FB includes the:

A: FB - the icon

B: Dimension Value, Line, and Arrowheads of the Motion-Dimension
MOVE the Mot-Dim FB = DRAG FB

MOVE the Mot-Dim FB = DRAG FB

Please read carefully

In the graphics-area, ...

To move the FB ...Drag the FB

The FB moves from Red-14-1 to Red-14-2 .

 
MOVE the Dimension Line/Arrowheads = CTRL+DRAG FB

MOVE the Dimension Line/Arrowheads
= CTRL + DRAG FB

In the graphics-area...

To move the Dimension Value, Line, and Arrowheads of the Motion-Dimension

CTRL + Drag the FB

The Motion-Dimension snaps to your mouse-pointer, from Red-14-1 to Red-14-2, and moves with the FB.
btn_delkeywordThe Kinematics Tree

Click the Kinematics-Tree tab, next to the Assembly-Tree, to explore the Kinematics-Tree.

The Part, Pin-Joint, and Motion-Dimension are the elements of a Rocker. A Rocker is a Motion-Part.

Kinematic-Tree with Elements for a Rocker

Kinematic-Tree with Elements for a Rocker

Icon-Element-Part

Part

PinJoint-Element-Part

Pin-Joint

MotDim-Element

Mot-Dim Rocker