Axis
Supertype: Component
Definition: abstract Component composed of a motion system that provides linear or rotational motion for a piece of equipment.
Version Info
| Introduced | Deprecated | Updated |
|---|---|---|
| 1.0 |
Documentation
Description
In robotics, the term Axis is synonymous with Joint. A Joint is the connection between two parts of the structure that move in relation to each other.
Linear and Rotary components MUST have Component::name that MUST follow the conventions described below. Use the Component::nativeName for the manufacturer’s name of the axis if it differs from the assigned Component::name.
MTConnect has two high-level classes for automation equipment as follows: (1) Equipment that controls cartesian coordinate axes and (2) Equipment that controls articulated axes. There are ambiguous cases where some machines exhibit both characteristics; when this occurs, the primary control system’s configuration determines the classification.
Examples of cartesian coordinate equipment are CNC Machine Tools, Coordinate measurement machines, as specified in ISO 841, and 3D Printers. Examples of articulated automation equipment are Robotic systems as specified in ISO 8373.
The following sections define the designation of names for the axes and additional guidance when selecting the correct scheme to use for a given piece of equipment.
Cartesian Coordinate Naming Conventions
A Three-Dimensional Cartesian Coordinate control system organizes its axes orthogonally relative to a machine coordinate system where the manufacturer of the equipment specifies the origin.
Axes Component::name SHOULD comply with ISO 841, if possible.
Linear Motion
A piece of equipment MUST represent prismatic motion using a Linear axis and assign its Component::name using the designations X, Y, and Z. A Linear axis Component::name MUST append a monotonically increasing suffix when there are more than one parallel axes; for example, X2, X3, and X4.
Rotary Motion
MTConnect MUST assign the Component::name to Rotary axes exhibiting rotary motion using A, B, and C. A Rotary axis Component::name MUST append a monotonically increasing suffix when more than one Rotary axis rotates around the same Linear axis; for example, A2, A3, and A4.
Articulated Machine Control Systems
An articulated control system’s axes represent the connecting linkages between two adjacent rigid members of an assembly. The Linear axis represents prismatic motion, and the Rotary axis represents the rotational motion of the two related members. The control organizes the axes in a kinematic chain from the mounting surface (base) to the end-effector or tooling.
Articulated Machine Axis Names
The axes of articulated machines represent forward kinematic relationships between mechanical linkages. Each axis is a connection between linkages, also referred to as joints, and MUST be named using a J followed by a monotonically increasing number; for example, J1, J2, J3. The numbering starts at the base axis connected or closest to the mounting surface, J1, incrementing to the mechanical interface, Jn, where n is the number of the last axis. The chain forms a parent-child relationship with the parent being the axis closest to the base.
A machine having an axis with more than one child MUST number each branch using its numeric designation followed by a branch number and a monotonically increasing number. For example, if J2 has two children, the first child branch MUST be named J2.1.1 and the second child branch J2.2.1. A child of the first branch MUST be named J2.1.2, incrementing to J2.1.n, where J2.1.n is the number of the last axis in that branch.
Inherited Properties
| Name | Type | Int | Dep | Multiplicity | Description |
|---|---|---|---|---|---|
id | ID | 1.0 | 1 | unique identifier for the Component. | |
name | string | 1.0 | 0..1 | name of the When provided, | |
nativeName | string | 1.1 | 0..1 | common name associated with Component. | |
sampleInterval | float | 1.2 | 0..1 | interval in milliseconds between the completion of the reading of the data associated with the This information may be used by client software applications to understand how often information from a The refresh rate for data from all child | |
sampleRate | float | 1.0 | 1.2 | 0..1 | DEPRECATED in MTConnect Version 1.2. Replaced by Component::sampleInterval. |
uuid | UUID | 1.0 | 0..1 | universally unique identifier for the Component. | |
coordinateSystemIdRef | ID | 1.8 | 0..1 | specifies the CoordinateSystem for this Component and its children. |
Inherited Relations
| Name | Type | Int | Dep | Multiplicity | Description |
|---|---|---|---|---|---|
hasDescription | Description | 1.0 | 0..1 | ||
hasComposition | Composition | 1.4 | 0..* | ||
hasComponent | Component | 1.0 | 0..* | ||
hasConfiguration | Configuration | 1.2 | 0..1 | ||
observes | DataItem | 1.0 | 0..* | ||
madeObservation | Observation | 1.0 | 0..* | ||
hasReference | Reference | 1.3 | 0..* | ||
hasComponentStream | ComponentStream | 1.0 | 0..1 | ||
isComponentOf | Component | 1.0 | 0..* |
Relations
| Name | Type | Int | Dep | Multiplicity | Description |
|---|---|---|---|---|---|
isAxisOf | Device | 1.0 | 0..* | (through Axes) |