Some of these relation types are available only for Parametric relation sets; others are only available when you create Assembly relation sets. They are identified below by the Parametric relations icon and the Assembly relations icon .
Value relations are used to define spatial relationships requiring the specification of positional values and orientation information.
The values specified can either be discrete or mathematical expressions, including if-then-else statements. The mathematical expression for a value relation can include the name of another value relation as a variable. This is particularly useful when working with inter-connected moving parts.
For distance and angle relations (known as value relations) values are required. These can be supplied as variables, numerical values, or mathematical expressions. Mathematical expressions can be used to link relations together, by specifying the name of an existing relation in the expression.
Using the animate facility, you can vary the value for a value relation automatically, with the specified value as the start value. The resultant sequence of graphics displays produces an animation of the relative part movements as the value is varied.
• Distance. The variable or measured distance between two reference elements.
• Angle. The variable or measured angle between two reference elements.
• Radius. The radius of cylindrical/spherical/toroidal objects (valid for modeling-mode relation-sets only).
• Diameter. The diameter of cylindrical/spherical/toroidal objects (valid for modeling-mode relation-sets only).
Logical relations are used to specify spatial relationships that require orientation information, but not positional values.
• Coincident. Aligns two reference elements, for example, the axes of two cylinders.
• Perpendicular. Sets one reference element perpendicular to another, for example, two planes.
• Parallel. Sets one Reference Element parallel to another, for example, two edges.
• Tangent. Sets one reference element at a tangent to another, for example, a cylinder (surface) and a plane.
• Symmetric. Sets parts and faces symmetric about a symmetry plane (modeling relation sets only).
Positional relations are used to specify positional information for 3D components (objects, faces, edges, or vertices). Valid positional relations are:
• Fixed. Fixes 3D objects/elements in global space.
• Rigid. Can be used to link together a group of 3D objects/elements, so that if one is moved, the others in the group move with it.
Joint relations are used to simulate realistic movement between two parts:
• Gear. The two radial elements will rotate at a user-defined transmission ratio.
• Rack. A radial element will rotate along a linear element at a user-defined ratio.
• Cam. A radial, spherical, or toroidal surface will move along a series of tangentially connected faces.
• Screw. A radial element will rotate around its axis and transfer the rotation into a linear movement, either to another part or itself.
Physical analysis relations are used to exclude or include objects from clash checking and physical simulation when you use Dynamic Positioning or create animations.
• Exclude. The part or assembly is not analyzed for clashes or used in physical simulation.
• Include. The face or faces are analyzed for clashes and physical simulation, but the remainder of the part is not analyzed.
and the Assembly relations icon 
.