Dialog: Function-Block: Motion-Path

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Dialog: Function-Block: Motion-Path

Motion-Path FB

see Add Motion-Path FB

The motion-values at the input-connector to a Motion-Path FB control the position of a Motion-Point along a sketch-path.

The Motion-Path FB can also add the motion-value at its input-connector to a constant*.

Use the Motion-Path dialog to edit the value of the constant, *.

Optionally, use the Motion-Path dialog to control and specify the length of a sketch-path or sketch-loop - typically a belt.

It it important to know the data-type of the motion-values at the input-connector. They should be Linear or Rotary - see Motion FB dialog

When the data-type is:

•Linear(mm) : the displacement of the Motion-Point is equal to the Linear motion-value

•Rotary(degrees) : the displacement of the Motion-Point is equal to the Rotary motion-value × total length of sketch-loop / 360

See more: Data-Type and Motion-Points

tog_minusHow to open the Motion-Path dialog

MD-Icon-FB-MotionPath

To open the Motion-Path dialog

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

OR

1.See How to Open a dialog

The Motion-Path dialog is now open.

Motion-Path dialog

Motion-Path dialog

Motion-Path dialog

There are usually two tabs:

Point Parameters

Length Control

If a Transition-Curve is a sketch-element in the sketch-loop, you will see three tabs.

Transition-Curves

Point Parameters tab

tog_minus Point Parameters 
MD-DIALOG-MOTIONPATH-PT-PARAMS-PT-PARAMS

Red-14-1b # Motion-Points: | Default = 1

To edit the number of Motion-Points along the sketch-loop.

1.Increase or decrease the # of Motion-PointsRed-14-1b

2.Click Red-14-6 button at the bottom of Point Parameters separator.

We distribute the Motion-Points equally along the Phase-RangeRed-14-2 and Length-RangeRed-14-3 of the sketch-loop.

If you Re-Generate Motion-Point, and ther is a Pin-Joint between a Part and a Motion-Point, you must add the Pin-Joint again.

Red-14-2 Phase Range | Default = 360 which is equivalent to the total length of the sketch-loop

Red-14-3 Linear-Range | Default = Length of the sketch-loop.

When # Motion-Points >1, the Motion-Points are distributed equally along the Phase-Range and Linear-Range of the sketch-loop.

1.Edit the Phase RangeRed-14-2 (deg)

OR

1.Edit the Linear RangeRed-14-3 (mm)

When you edit Phase-RangeRed-14-2, the Linear-Range updates automatically, and vice-versa.

These two parameters indicate the proportion of the sketch-path over which to distribute Motion-Points (when # Motion-Point >1).

These parameters distribute Motion-Points (when # Motion-Points > 1) over a range (length) that is different to the total-length of the sketch-path.

The distribution of the Motion-Points is best illustrated with examples. We urge you to EXPERIMENT.

Example

Say : Actual length of a sketch-loop is 127.5mm

The Number of Motion-Points = 3

Default: Phase-Range =360 (and Linear-Range = 127.5)

The 3 Motion-Points are equally spaced over 127.5mm. The distance between each Motion-Point = 127.5/3 = 42.5mm

Position of Motion-Point #1 = 0mm, Motion-Point #2 = 42.5mm, and Motion-Point #3 = 85.0mm

Edit Phase-Range = 120 (and Linear-Range = 42.5)

The 3 Motion-Points are distributed over a linear-length of = 42.5mm

The distance between each Motion-Point is 42.5/(3-1) = 21.25mm

Position of Motion-Point #1 = 0mm, Motion-Point #2 = 21.25, and Motion-Point #3 = 42.5mm

Phase Offset (deg)Red-14-4 | Default = 0

Linear Offset (mm)Red-14-5 | Default = 0

Phase Offset and Linear Offset move ALL of the Motion-Points along the sketch-loop. The offset value indicate the position of Motion-Point #1 when the motion-value at the input-connector of the Motion-Path FB is equal to 0; or when a wire is not connected to its input-connector.

Phase-Offset: equates the length of the sketch-loop to 360 degrees of a circle.

Linear-Offset: equates the length of the sketch-loop to its actual linear length.

Example - we urge you to EXPERIMENT.

A sketch-loop is 127.5mm long. There is 1 Motion-Point.

•A Phase-Offset=40 (deg) moves the Motion-Point #1 to 127.5×40 ∕ 360=14.16mm along the sketch-loop. All other Motion-Points move by the same distance.

•A Linear-Offset=40 (mm) moves the Motion-Point #1 to 40mm along the sketch-loop. All other Motion-Points move by the same distance.

Red-14-6 button

If you edit the Number of Motion-PointsRed-14-1b parameter, you must click the Regenerate Motion-Points button.

tog_minus Point List and Data Display 
MD-DIALOG-MOTIONPATH-PT-PARAMS-PT-LIST

Headers: Name | Index | Phase (read-only)

•Name : the element-name of each Motion-Point.

If you click on a Motion-Point in the list, it shows as the Selected-Color in the graphics-area.

•Index : the number of the Motion-Point

•Phase : the relative displacement along the sketch-path, relative to the Motion-Point #1

Display Motion-Point #1 as

You can show the position of Motion-Point #1 as it move along the sketch-loop.

◉Show Nothing - nothing shows above the Motion-Point #1

◉Show Distance - the linear position above Motion-Point #1 as it moves along the sketch-loop

◉Show Phase - the angular phase above Motion-Point #1 as it moves along the sketch-loop

Length Control tab

tog_minus Control Length of Path 

You can select a dimension to control the length of the sketch-loop that is associated with the Motion-Path FB.

The dimension you select is called the Control-Dimension - see Note 1: Control-Dimension

Important

In the Part-Editor, the sketch-loop should be fully defined before you select the Control-Dimension.

Then, as you edit the Control-Dimension, the shape of the sketch-loop is more predictable - see Note 1

MD-Dialog-MotionPathFB-LengthControl-Control

Red-14-1 /

To control the length of the Motion-Path with a Dimension:

1.Click the ButtonRed-14-1

We open the Part-Editor for you.

2.Click a dimension in the graphics-area that can control the total length of the sketch-loop - see Note 1

We close the Part-Editor for you.

The Dimension name of the Control-DimensionRed-14-2 is now below the buttonRed-14-1.

For example, DimPtoP4

The value of the Control-Dimension (read-only) is now in box Red-14-3

For example, 225

When you do not want to control the length of the Motion-Path with a dimension:

1.Click Red-14-1

Note 1: control-dimension

Rule: The Control-Dimension must be.

DimPtoP#

the distance between two Points

DimL#

the length of a Line

Or, the control-dimension Must Not be:

DimPtoL#

the perpendicular distance form a Point to a Line, or a Point to the X-axis, or a Point to the Y-axis

DimLtoL#

the distance between two parallel Lines

AnglePPP#

AngleLtoL#

an angle

 

A dimension that is gray before you select it.

For example, a Design-Set already controls the dimension.

Parameters

Control-Dimension Length - read-onlyRed-14-3

The value of the Control-Dimension.

Actual Path Length - read-onlyRed-14-4

The length of the sketch-loop associated with the Motion-Path FB.

Target Path LengthRed-14-5

We recommend you use the Spin-Box tool to edit the Target-Path Length with a small Spin- Increment.- e.g. 10mm

If the SPIN-BOX TOOL does not show, double-click and double-click again in the data-box.

Round and then edit the length of the sketch-loop associated with the Motion-Path FB - see Note 2

Control-Dimension MinRed-14-6 / MaxRed-14-7 - see Note 3 below

When you select the Control-Dimension:

•Control-Dimensions MinimumRed-14-6 is estimated as 0.5 × Control-Dimension - see Note 3.

•Control-Dimensions MaximumRed-14-7 is estimated as 2.0 × Control-Dimension - see Note 3.

If required:

Edit the Control-Dimension MinimumRed-14-6 and MaximumRed-14-7 limits - see Note 2.

tog_minus Belt Tooth Pitch 
MD-Dialog-MotionPathFB-LengthControl-BeltPitch

Belt-Tooth-Pitch

The Belt-Tooth-Pitch does not change the belt length.

The diameter of a Pulley is a function of the number of teeth AND Belt Tooth-Pitch.

See Pulley dialog
tog_minusNotes 2 and 3

Note 2: Target Path-Length

Edit the Target Path-Length with small increments. If the Actual Path Length does not change, see Note 3

Note 3: Control-dimension minimum and/or Control-Dimension Maximum

If the Actual Path Length does not change, you may see the message in Feedback-Area (below the graphics-area)

MD-FeedbackMsg - ControlDimensionMin too samall

The default values for the Control-Dimension Min or Control-Dimension Max are such that the Actual-Path Length can be equal to the Target Path Length.

However, it is possible that the Root-Finding Math to calculate the Control-Dimension to find the Actual-Path Length from the Target Path Length is confused!

To reset the Root-finding Math:

•Increase or decrease the Control-Dimension Min/MAX, then try to edit the Target-Path-Length again.

•You may need to edit these values to be almost equal to the actual length of the Control-Dimension.
tog_minusTransition Curve tab
MD-Dialog-MotionPathFB-TransitionCurve

This tab will show If there is a Transition-Curve in the sketch-loop.

# Sprocket Teeth

Maximum = 11 ; Minimum = 3

Chain Link-Length

When the Target Path Length is set, you can enter the Chain-Link Length to give an integer number of teeth.

MOTION-PATH AND DATA TYPES

tog_minus Data-Type and MOTION-POINTS

The position and motion of Motion-Points along the sketch-loop is a function of the Data-Type at the input-connector to the Motion-Path FB.

The Data-Type at the input-connector must be Linear or Rotary.

Data-Type = Linear

The position of the Motion-Point #1 along the sketch-loop has a scale of: 1mm at input = 1mm along sketch-loop

the position of the Motion-Point #1 along the sketch-loop = motion-value at input-connector(mm)

Data-Type = Rotary

The position of Motion-Point #1 along the sketch-loop has a scale of: 1deg at input = Length of sketch-loop / 360

∴ the position of the Motion-Point #1 along the sketch-loop = motion-value at input-connector(degrees) × (Length of the sketch-loop /360)

The Motion-Point moves along the total length of the sketch-loop when the input is 360.