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Add Magnetic-Joint

Magnetic-Joint

See also: Magnetic-Joint dialog ( YouTube Video : http://youtu.be/IME9Eb4mpQE )

 Use Magnetic-Joints ONLY for special modeling - for example, to reverse-engineer the motion of a Cam-Follower from the shape of an imported Cam. Magnetic-Joints are solved with iterative, root-finding techniques. All other kinematic joints use closed-form equations for exact and fast evaluations. Therefore, a model with a Magnetic-Joint is ~100s'× slower to solve than a model with only Slide-Joints, Pin-Joints, and Ball-Joints. Most models (99%?) do not need a Magnetic-Joint.

Terminology

 Magnetic-Joint : A Magnetic-Joint pulls a circular Profile to be in continuous contact with an irregular Profile (or Curve). The circular Profile and irregular Profile (or Curve) are in different kinematic-chains. After you add a Magnetic-Joint, the motions of the kinematic-chains are related by the contact between the circular and irregular profiles (or curve). Point-Cloud : X-Y or R-Θ coordinates. Use a Point-Cloud FB to import the Point-Cloud coordinates. Curve : The smooth shape that we derive for you from the Point-Cloud coordinates.

Preparation for Add Magnetic-Joint (Typical)

The Magnetic-Joint pulls a Circular-Profile onto an Irregular-Profile.

 A Part (and kinematic-chain) to which the Irregular-Profile is a child. An Irregular-Profile, which is a •Profile that you add to a sketch-loop or •Curve that you calculate from a Point-Cloud A Part (and kinematic-chain) to which the Circular Profile is a child. The Motion-Dimension FB that becomes driven by the action of the Magnetic-Joint.

Add Magnetic-Joint

STEP 1: Pre-Position the Circular Profile

 1.HOME the model Select the Home key, or use the ALT+H keyboard shortcut, or do Run menu/toolbar > Home. 2.Edit the Motion-Dimension FB | Base-Value so that the: Distance from the Circular-Profile to the Irregular-Profile  ... ... <  0.5 × Radius of Circular-Profile Note: See also Magnetic-Joint dialog > Advanced

STEP 2:Start the Add Magnetic-Joint command

 1.Add menu > Mechanism sub-menu  > Add Magnetic-Joint OR 1.Kinematic elements toolbar > Add Magnetic-Joint

STEP 3:Select the elements:

 1.Click the Irregular Profile 2.Click the Motion-Dimension FB that you want to 'drive' with the Magnetic-Joint. 3.Click Circular Profile

STEP 4: Complete the Command

 1.Command-Manager: Click in the Command-Manager.

Result: (usually)

 The Magnetic-Joint pulls the Circular-Profile to be in contact with the Irregular-Profile. A Point Symbol is at the contact. The Magnetic-Joint FB is near to the Point-Symbol There is a Magnetic-Joint icon below and right of the Motion-Dimension FB that is driven by the Magnetic-Joint.

STEP 5: Open the Magnetic-Joint dialog

Video:

Video: Add a Magnetic-Joint