Dialog: Function-Block: Motion-Path

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Dialog: Function-Block: Motion-Path

Motion-Path FB

see Add Motion-Path FB

A Motion-Path FB adds a Motion-Point to a sketch-path.

When you connect a wire to the input-connector of the Motion-Path FB, the Motion-Point moves along the sketch-path.

The Motion-Path dialog-box allows you to add more Motion-Points, and to distribute them along the sketch-path, control the length of the sketch-path, ... .

Important Note on Data-Type

Motion-Values have Linear, Rotary, and other units. The units indicate its Data-Type.

When the Data-Type at the input-connector to the Motion-Path FB have:

•Linear units, say mm, the Motion-Point moves by a distance = input (mm)

•Angular units, say degrees, the Motion-Point moves by a distance = input × total length of sketch-path/360 (mm)

The position of the Motion-Point cannot easily not be predicted with other units.

See more Data-Type and Motion-Points

Open Motion-Path dialog-box

MD-Icon-FB-MotionPath

Edit the Motion-Path FB:

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

- or -

1.See How to Open a Dialog-Box

The Motion-Path dialog-box is now open.

Motion-Path dialog-box

MD-Dialog-MotionPathFB

Note: Transition Curves tab - information coming with MD16

Point Parameters tab

tog_minusPoint 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-path:

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

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

Motion-Points will distribute equally along the Phase-RangeRed-14-2 / Length-RangeRed-14-2 of the sketch-path.

Note - If you click the button Red-14-6, and you have also made Pin-Joints between Parts and Motion-Points, you must add the Pin-Joints again.

Red-14-2 Phase Range | Default = 360 (full-range)

Red-14-3 Linear-Range | Default = full-range of the sketch-path (total-length).

To distribute Motion-Points (when # Motion-Points > 1) over a range (length) that is less than the full-range (total-length) of the sketch-path.

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.

When to edit a Range parameter

When you generate more than one Motion-Point the Phase-Range and Linear range parameters specify the extent over which to distribute Motion-Points along the sketch-path.

Motion-Points are equally distributed along the Phase-Range and Linear-Range of the sketch-path.

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

Example

Actual length of a sketch-path is 127.5mm

Number of Motion-Points = 3.  

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

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

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

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

The 3 Motion-Points are spaced now over linear-length of 127.5/3 = 42.5mm.

The distance between each Motion-Point now 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 of ALL of the Motion-Points along the sketch-path. The offset values 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-path to 360 degrees of a circle.

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

Example

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

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

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

Red-14-6 button

Click the button to generate Motion-Points as specified by the Number of Motion-PointsRed-14-1b parameter.

 
tog_minusPoint List and Data Display 
MD-DIALOG-MOTIONPATH-PT-PARAMS-PT-LIST

Headers: Name | Index | Phase (Read-Only)

•Name is the name to identify the Motion-Point

If you click on a Motion-Point in the list, it shows as red in the graphic-area.

•Index is the # Motion-Point

•Phase is the relative displacement along the sketch-path, relative to the fist Motion-Point

Display Motion-Point #1 as:

You can show the position of Motion-Point #1 on the sketch-path.

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

◉Show Distance - the linear position of Motion-Point #1 is on the sketch-path

◉Show Phase - the 'angular' position of Motion-Point #1 is on sketch-path. 360 is the total-length of the sketch-path.

Length Control tab

tog_minusControl Length of Path

Select a dimension to control the length of the sketch-path that is associated with the Motion-Path FB.

The dimension becomes the Control-Dimension.

Important

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

Then, as you edit the Control-Dimension, the sketch-path is more predictable.
MD-Dialog-MotionPathFB-LengthControl-Control

OR

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

1.Click the Button

The Part-Editor opens.

2.Click a dimension that can control the total length of the sketch-path - see Note 1

The Part-Editor closes.

The name of the Control-Dimension is now under the button.

E.g. Dimension name DimPtoP2

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

1.Click the Button

Read Only Parameters

Control-Dimension Length (read-only)Red-14-3

The active value of the Control-Dimension.

Actual Path Length - (read only)Red-14-4

The length of the sketch-path associated with the Motion-Path FB

Target Path LengthRed-14-5

3.Edit the length of the sketch-path 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.

4.Edit the Control-Dimension MinimumRed-14-6 and MaximumRed-14-7 limits

tog_minus        Notes 1,2,3

Note 1: Control-Dimension

The control-dimension should be:

DimPtoP#

the distance between two Points

DimL#

the length of a Line

The control-dimension should NOT be:

DimPtoL#

the perpendicular distance form a Point to a Line

Gray before you select it. E.g. it is controlled with a Design-Set

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 min and/or MAX

Message in Feedback-Area:

MD-FeedbackMsg - ControlDimensionMin too samall

The default values for the Control-Dimension Min or 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 is confused!

•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_minusBelt Tooth Pitch 
MD-Dialog-MotionPathFB-LengthControl-Belt

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-box

MOTION-PATH AND DATA TYPES

tog_minusData-Type and MOTION-POINTS

The position of the Motion-Points along the sketch-path 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-path has a scale of 1 : 1 with the motion-value at the input-connector to the Motion-Path FB

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

Data-Type = Rotary

The position of Motion-Point #1 along the sketch-path has a scale of 360 : 1 × Path-Length.

∴ the position of the Motion-Point #1 along the sketch-path =  Total Length of the sketch-path × motion-value at input-connector(degrees)/360)
tog_minusOutput Data-Types from Function-Blocks

Motion FB > Output Data-Type

Set Output-Data-Type as Rotary or Linear.

See also Motion FB dialog-box

Linear-Motion FB > Output Data-Type

The Output Data-Type is Rotary

Math FB > Output Data-Type

Set Output Data-Type as Rotary Coordinates or Linear Coordinates.

See also Math FB