Functional Joints

When you add mates between components, the mates that impact the same components are grouped into joint types. The following are the types of joints and are categorized based on their degrees of freedom. The degrees of freedom are calculated according to the rotation of a component around the axes and a linear translation in X, Y, or Z directions.

Name Degrees of Freedom Example
Planar

1 rotation, 2 translations

Occurs when you add a coincident mate between a plane of one component and a plane of another component. It allows the movement along two directions where the third direction is locked by a coincident mate.

Prismatic

0 rotation, 1 translation

It consists of either two coincident mates or a concentric mate and a parallel mate. The component can only be moved in one direction.

Rigid

0 rotation, 0 translation

Occurs when two components are constrained by a Prismatic mate and you add a third coincident mate, between another plane from each of the components.

Cylindrical

1 rotation, 1 translation

Occurs when a component can be moved along the axis of the concentric mate and rotated about the concentric mate at the same time.

Revolute

1 rotation, 0 translation

Occurs when two components are constrained by a coincident mate between lines and another coincident mate between two planes.

Spherical

3 rotations, 0 translation

It is based on a coincident mate between vertices or spheres and allows the rotation of the component around the selected vertices like a ball joint.