What is Reference Geometry

Reference Geometry is a sketch-element that is copied onto the Base-Part in the 'active' Mechanism-Editor from a Part in a different Mechanism-Editor. If you edit or move the source sketch-element, the Reference Geometry in the active Mechanism-Editor also updates to the new size or position.

Reference-Geometry may be moving.

Add Reference Geometry



Mechanism Local Toolbar : Add Reference Geometry

Add Reference Geometry makes a copy of a sketch-element in a different Mechanism-Editor to the active Mechanism-Editor.

The copy has same kinematic motion-values as the original sketch-element. The new sketch-element in the active Mechanism-Editor is termed a 'reference sketch-element'.

What is it:

Reference Geometry:

Makes a 'linked' copy of a 'source' sketch-element that is in a Part in a different Mechanism-Editor, as a 'reference' sketch-element in the Base-Part of the active Mechanism-Editor.

The new 'reference' sketch-element can give position, velocity and acceleration motion-values.

The 'reference' sketch-element moves when:

you edit position of the 'source' sketch-element in the 'source' Part
the 'source' sketch-element is a child to a Part that in a moving kinematic-chain.

What to do:

1.Click a Mechanism-Editor in to which that you want to copy sketch-elements from another Mechanism-Editor.
2.Toggle Off Display Profiles (you cannot make a reference copy of Profile Contours, but you may 'try' to select one)
4.Spin the model so you can see the sketch-element, in grey, in another Mechanism-Editor, that you want to copy to the active Mechanism-Editor
5.Click Add Reference
6.Click a Part in the Active Mechanism-Editor
7.Click a sketch-element (not a Point) in the other Mechanism-Editor
8.Click OK in the Command-Manager

Do Steps 1-8 again to copy more sketch-elements.


MechDesigner copies the sketch-element from the source Mechanism-Editor to the Part in the active Mechanism-Editor. It is Reference Geometry.



How to...

Add Reference Geometry


Have a minimum of two Mechanism-Editors. It is usual that the Mechanism Planes should be parallel or coplanar. If they are not, the results are not easy to predict.


Reference sketch-elements (the copy in the active Mechanism-Editor) are orange.
You cannot delete or edit a reference sketch-element. You must delete or edit the source sketch-element in the source Mechanism-Editor.
Reference Geometry elements are given as 'RefLine' or 'RefCircle' in the Selection-Window.

To transfer the Motion of the source sketch-element to a reference sketch-element:

The Mechanism Planes should be parallel or coplanar.
The Show Other Mechanisms tool must be active to transfer the motion (position, velocity and acceleration) to the Reference Geometry.
Make the source sketch element a Circle. You can select the centre-point of the Circle when you want to measure the motion of the centre-Point relative a Line or Point in the Active Mechanism-Editor.

The Motion data gives position, velocity and acceleration of the Circle's centre-point in the active Mechanism-Editor.

See Also:


tog_minusHow to Add Reference Geometry - Further Details

You need two Mechanism-Editors.

A 'Source' Mechanism-Editor with a sketch-element in a Part. Call it Mechanism 'A'.
A 'Reference' Mechanism-Editor to which you want to add the 'reference' sketch-element. Call it Mechanism 'B'.


STEP 1: Make Mechanism 'B' active

Add Reference Geometry - Preparation

STEP 2: Spin to view the sketch in the source Mechanism-Editor.

In the image to the left, the active Mechanism is in front of the source Mechanism-Editor

You cannot select the grey geometry in the Source Mechanism-Editor, grey, before you start Add Reference.


STEP 3: Click Add Reference in the Mechanism Local-Toolbar
- or -
Use the Mechanism menu > Add Reference

Dialog RefGeometry

The Command-Manager instruction is:

Add Lines, Circles or Arcs to the active Mechanism with Lines, Circles or Arcs in a different Mechanism.


STEP 4: Click the Part1s-red in the active Mechanism-Editor, onto which you want to add the reference geometry.
STEP 5: Click the sketch-element2s in the source Mechanism-Editor you want to 'copy' as a reference to the active Mechanism-Editor.

Add Reference Geometry - Example completed

STEP 6: Click OK

The sketch-element shows in the active Mechanism-Editor.

The colour of the Reference Geometry (sketch-element) is Orange3s

Help Files for MechDesigner and MotionDesigner 11.1 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd