Total Degrees of Freedom
|
Rotation Axis
|
Translation Axis
|
Connection Type
|
Constraints associated with specific DOF
|
0
|
0
|
0
|
Weld—Glues two bodies together.
|
|
0
|
0
|
0
|
Rigid—Glues two parts together while changing the underlying body definition. Parts constrained by a rigid connection constitute a single body.
|
|
1
|
0
|
1
|
Slider—Translates along an axis.
|
Plane-plane coincident
|
1
|
1
|
0
|
Pin—Rotates about an axis.
|
|
2
|
2
|
0
|
General
|
Point-point align if the point is on an edge.
Edge on plane.
|
2
|
1
|
1
|
Cylinder—Translates along and rotates about a specific axis.
|
Point on line
Plane-plane orient
|
2
|
0
|
2
|
General
|
Edge on plane provided the plane is neither perpendicular nor parallel to the edge
Plane-plane orient
|
3
|
3
|
0
|
Ball—Rotates in any direction.
|
Point-point align
|
3
|
2
|
1
|
General
|
Edge on plane
Point on line (line and edge must align)
|
3
|
1
|
2
|
Planar—Bodies connected by a planar constraint move in a plane with respect to each other. Rotation is about an axis perpendicular to the plane.
|
Plane-plane coincident/parallel
|
3
|
0
|
3
|
General
|
Plane-plane orient
Plane-plane orient (not parallel to the first set of planes)
|
4
|
3
|
1
|
Bearing—Combines a ball connection and a slider connection.
|
Point on edge
|
4
|
2
|
2
|
General
|
Edge on plane
|
4
|
1
|
3
|
General
|
Plane-plane orient
|
4
|
3
|
1
|
Slot
|
Point on a non-straight trajectory
|
3
|
3
|
0
|
Gimbal—Aligns the centers of two CSYS (see below).
|
Point to point
|
5
|
3
|
2
|
General (see below).
|
Point on plane
|
6
|
3
|
3
|
6DOF—Rotates and translates in any direction (see below).
|
|
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