See: Add Magnetic-Joint.


A Magnetic-Joint makes a circular profile in a Part become in continuous contact with an irregular* Profile in a different Part.

The Magnetic-Joint calculates the motion-values [positional, velocity] of the Part with the circular Profile.

Note * : The shape of the irregular Profile can be derived from a Point-Cloud or a sketch-loop.

Open the Magnetic-Joint dialog box



1.Double-click a Magnetic-Joint icon in the graphic-area.

- or -

Magnetic-Joint dialog-box


The Magnetic-Joint dialog-box has two separators:

Curve Following Options...

Radius Control

tog_minus Curve Following Options 


'Enable Magnetic-Joint' check-box is active

The circular Profile is in continuous contact with the irregular Profile or Point-Cloud.

'Enable Magnetic-Joint' clear the check-box.

The circular Profile is not in continuous contact with the irregular Profile or Point-Cloud.



The image shows the circular ProfileRed-14-1 on the out-side of the irregular ProfileRed-14-2.



The image shows the circular Profile Red-14-1 on the in-side of the irregular ProfileRed-14-2.

tog_minusRadius Control 



Optionally, edit the effective radius of the Cam-Roller.

Not Overriding Circle Radius [default]

The circular Profile moves along the irregular Profile.

The Radius parameter is 0mm and Read-Only

Modify Circle Radius

Click the check-box to let the circular Profile overlap irregular Profile.


When the Radius parameter is '0mm', the Centre of the Circular Profile moves along the Irregular Profile as normal.
When the Radius parameter is '3mm', the Centre of the Circular Profile is 3mm inside the Irregular Profile.


This is useful if you use a CMM machine with a probe diameter that is different to the Cam-Roller, and the CMM software does not have 'Probe Compensation'.

When the CMM data does not compensate for the Probe Diameter, you would use Modify Cycle Radius to recreate the contact between the irregular-Profile and the Cam-Roller.

Offset Profile Radius = Radius of Actual Cam-Roller – Radius of CMM Probe

R = Rcf – Rp

Rcf = Cam-Roller Radius; Rp = CMM Probe Radius.

Tutorials and Reference Help Files for MechDesigner and MotionDesigner 14.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd