# Glossary

## C

cylindrical joint A translation type joint between two products along an axis with a rotation about that axis. Number of degrees of freedom is 2 (1 translation and 1 rotation). This joint was called Actuator in Version 4.
command An angular or linear parameter that drives the mechanism. See degrees of freedom.
custom frame A frame of interest for custom user needs.

## D

degrees of freedom The number of possible independent rotation or translation movements of a joint up to 360 degrees.
design frame A frame of interest that is located on a part and and can be reused in a joint creation dialog to create joints between parts.  This feature should be used to create joints between multiCAD parts.
dressup A list of models attached to a set of the kinematics model. These models have the same motion as the set.

## F

fixed product The product that remains stationary when the kinematics mechanism is in motion.
frame of interest Coordinates that can be used to create the mechanism or later on integrate the mechanism in a workcell.  The frames of interest are of four kinds: base, custom, design, and tool.

## G

gear joint A joint type between three products (two products are pinions, the other is a reference). Number of degrees of freedom is 1 (rotation).

## J

joint A constraint between geometric entities of two or three products. There are several types of joints.
joint stop An imposed limit applied to a joint.
jog To simulate motion.

## K

kinematic mechanism A mechanism comprising several products that are connected by joints. It can be simulated when the number of commands is equal to degrees of freedom (in this case the mechanism is said to be complete).
kinematic product A rigid product defined in a single geometric set that contains all the elements required to describe the kinematics mechanism and its motion.
kinematic simulation A simulation of the mechanism's motion using commands. Simulation can be immediate (commands are used one by one) or on request (one or more commands are used with a given number of steps).

## L

law A numeric or graphic representation of the commands applied to a kinematics mechanism as a function of time.

## P

planar joint A joint type between two products. Number of degrees of freedom is 3 (1 rotation and 2 translations).
prismatic joint A translation joint between two products along an axis with no rotation about that axis. Number of degrees of freedom is 1 (translation).
product tree See specification tree.
PT/CRV joint A point/curve joint between two products. Number of degrees of freedom is 4 (3 rotation and 1 translation) for a 3D mechanism and 2 (1 rotation and 1 translation) for a 2D mechanism.
PT/SUR joint A point/surface joint between two products. Number of degrees of freedom is 5 (3 rotations and 2 translations).

## R

rack joint A gear/rack type joint between three products (one product is the rack, another is the rack, the other is a reference). Number of degrees of freedom is 1 (combined translation and rotation).
revolute joint A revolute joint about an axis between two products with no translation along that axis. Number of degrees of freedom is 1 (rotation).
rigid joint A rigid (fully restricted) joint between two products. There are no degrees of freedom associated to this joint.
roll/CRV joint A rolling type joint between two products that include curves. There is no sliding motion with this type of joint. Number of degrees of freedom is 2 (1 rotation and 1 translation) for a 3D mechanism and 1 (translation) for a 2D mechanism.

## S

screw joint A screw/nut type joint between two products relative to an axis. Number of degrees of freedom is 1 (combined translation and rotation).
slide/CRV joint A rolling type joint with a sliding motion between two products that include curves. Number of degrees of freedom is 3 (2 rotations and 1 translation) for a 3D mechanism and 2 (1 rotation and 1 translation) for a 2D mechanism.
specification tree The list appearing to the left of the window that provides the names of all items in the geometric area. Selecting the + symbol expands the tree. Selecting the - symbol collapses it.
spherical joint A spherical joint between two products. Number of degrees of freedom is 3 (3 rotations) for a 3D mechanism and 1 (rotation) for a 2D mechanism. This joint was called PT/PT in Version 4.

## T

TCP The Tool Center Point or TCP is the location on a device that will interact with another device or part.
tool frame The frame of interest that defines the tool action point.
tool tips The tool tips are the parts of the device that are supposed to be in contact with the product for a given home position.  The tool tips are excluded from the clash analysis in tools like DPM Body-in-White's weldgun search.

## U

U joint A universal joint between two products. Number of degrees of freedom is 2 (2 rotations).