Spatial Kinematic-Chains and Ball-Joints.
When you cannot model a kinematic-chain on one Plane, it is a Spatial Kinematic-Chain.
A spatial kinematic-chain may have Cylindrical, Spherical and Helical-Joints. However, MechDesigner is limited to those kinematic-chains with Spherical-Joint. With Packaging, Textile and Automation machinery, the spherical-joint is used almost exclusively. In fact, I have used the Cylindrical-Joint only one time, and a Screw-Joint only one time.
In MechDesigner, we use the term Ball-Joint for the Spherical-Joint.
IMPORTANT:
Ball-Joints and Mechanism Misalignment
In machines, Rod-End Bearings at each end of one Part are frequently used to allow a small amount of misalignment between two parts in a kinematic-chain. When the primary function of the Ball-Joints is to make sure the mechanism does not bind, then model the mechanism on one Plane with Pin-Joints as a planar kinematic-chain. But, of course, in your machine, use Rod-End bearings.
This Tutorial
•We will look at 'Planar' and 'Spatial' mechanisms.
•We will design a typical spatial mechanism.
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