Motion-Parts and Motion-Points

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Motion-Parts and Motion-Points

Motion-Parts and Motion-Points

Comparisons between the Motion-Part and Motion-Point

Motion-Parts are:

Parts that have their motion specified by a Motion-Dimension FB

A Joint constraint the Part to either Rotate or Slide

Motion-Points are:

Points that have their motion specified by a Motion-Path FB

A sketch-element constraints the Point to slide along its length

Motion-Point <

> Motion-Part

Constrained by a Sketch-Element <

> Constrained by a Joint

Motion-Path FB <

> Motion-Dimension FB

Motion-Parts

Motion Dimension FB

A Motion Dimension FB:

identifies a Part - that becomes a Motion-Part - we want to move with a specified motion

specifies the position of the Part relative to a different Part

Kin-Rocker

Rocker

A Rocker is a Part joined to a kinematically-defined Part with a Pin-Joint with a Motion Dimension FB to define its rotational angle

between Lines in the two Parts that radiate from the Pin-Joint.

Kin-Slider

Slider

A Slider is a Part joined to a kinematically-defined Part with a Slide-Joint, that uses a Motion Dimension Function-Block to define the directional distance between Points at the end of the Lines used to define the Slide-Joint.

Motion-Points

Motion-Path FB

A Motion-Path FB is similar to a Motion-Dimension.

A Motion-Path FB

adds a Motion-Point to a sketch-element and identifies it as the Point we want to move with a specified motion

specifies the position of the Motion-Point along the sketch-element or sketch-loop

There are many application that can use a Motion-Path FB.  However, there are two useful 'Motion-Dyads'.

See Tutorial 16.

Simple Ram-R Example

Ram-R

The Ram-R is a similar to an R-R-R Dyad, but one of the Parts extends.

The Ram-R makes use of the Motion-Path FB. The Motion-Path FB adds a Motion-Point to a sketch-element (CAD-Line) in one Part.

The other Part is joined to the Motion-Point with a Pin-Joint.

motion-values are given to the Motion-Path FB by Motion FB.

The Red Arrow in the image shows the Motion-Path of the Motion-Point along the CAD-Line of one of the Parts.

Simple Ramp-P Example

Ram-P

The Ram-P is a similar to an R-R-P Dyad, but one of the Parts extends.

The Ram-P makes use of the Motion-Path FB. The Motion-Path FB adds a Motion-Point to a sketch-element (CAD-Line) in one Part.

The other Part is joined to the Motion-Point with a Pin-Joint.

motion-values are given to the Motion-Path FB by Motion FB.

The Red Arrow in the image shows the Motion-Path of a Point along the CAD-Line of one of the Parts.

tog_minusDegrees-of-Freedom & Mobility of Motion-Parts

How to Add

Rocker

KinChain-a1

1.Add a PartRed-14-1b

The Part is a 'Free' Part.

The Part has three Degrees-of-Freedom

KinChain-1ab

2.Add a Pin-Joint between two PointsRed-14-2

The Pin-Joint removes two Degrees-of-Freedom.

The Part now has one Degree-of-Freedom

KinChain-1ac

3.Add a Motion-Dimension FBRed-14-3

The Part has Zero (0) Mobility. Notice the Part-Outline and Pin-Joint are green

 

'Expand' then 'Play'

 

See Video to the Left.

Kinematics-Tree

KT-Rocker1

The elements that define a Rocker are:

Dowel

Pin-Joint

Part

Part

MD-32-FB-PINMDA-small

Mot-Dim Rocker

tog_minusSlider

tog_minusHow to Add