AIA/NAS 938-2013 pdf download MACHINE AXIS AND MOTION NOMENCLATURE
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SCOPE
Purpose: This specification covers axis and motion nomenclature for numerically controlled equipmentThese requirements are intended to standardize programming and facilitate the interchangeability ofprograms by prescribing the letter designation of each axis, and the positive direction of each axis.
Classification: The specification includes standards for Class Ill (Positioning), Class IV (Contouring), andClass 1ll/Class IV (Contouring/Positioning Combination Systems) numerically controlled equipment.
Definitions of terms used in this standard are in accordance with the current version of the ElAAutomation Bulletin,“Glossary of Terms for Numerically Controlled Machines.”
Revisions to these standards will be proposed as technical progress warrants
APPLICABLE SPECIFICATIONSAll existing NAS specifications applicable to numerical control
REQUIREMENTS
Coordinate SystemThe standard right hand coordinate system shall be used and shall give the coordinates of a moving toowith respect to a stationary workpiece. (See Figures 1, 2, & 3).
The basic coordinate axes of the system shall be designated by unprimed letters as shown in FIGURE 1(See paragraph 3.9)
The z Axis of MotionThe z axis of motion is parallel to the principal spindle axis of the machine.
If the spindle can be swiveled or gimbaled, the z axis of motion is parallel to the axis of the spindle whenthe latter is perpendicular to the work-holding surface.
lf there are several spindles, one shall be selected as the principal one.
If there is no spindle, the z axis is perpendicular to the work-holding surface.
Positive z is in the direction from the work-holding means toward the tool-holding means.
Positive command to moving tool moves tool away from work.
Positive command to moving work surface moves work away from tool.
The x Axis of MotionThe x axis of motion is horizontal and perpendicular to z.
If z is horizontal. positive x is to the right looking from the spindle toward the workpiece
If z is vertical, positive x is to the right looking from the front of the machine toward the back, or whenviewing the workpiece from the machine operator’s normal operating position (See Figure 14 & Fiqure15)