2.)Straight Line Motion
This type of motion would allow the programmer of the machine to command perfectly straight line movements within the machine. Unlike the rapid motion type, the straight line motion would allow the programmer to vary the rate of the motion or feed rate to be used during the movement. Examples of using straight line motion would be turning a straight diameter, taper, when milling straight surfaces, and when drilling for this is because these examples require straight cutting movement.
The common word to specify a straight line motion into a machine would be G01, for within this command the programmer will include the preferred end point within each of the axes.
This motion type would cause the machine to move in the direction of a circular path and is used to generate the radii in machining. When talking about points on circular motion feed rate, it is equal to that of straight line motion.
Other than that of straight line motion and rapid motion, there are two G codes that are commonly used when programming a circular motion into a machine. These are G02 and G03. G02 is used when the programmer desires a clockwise motion into the machine while G03 is used to make an anti-clockwise motion. To know which of the commands to use, the programmer must view the movement with the same perspective as to what the motion of the machine will be, may it be clockwise or anti-clockwise.
Another requirement that would be programmed into a machine that would be using circular motion is that the programmer must specify the radius of the arc that is to be generated. With brand new technological advances in CNC, an “R” word is now used to specify the radius.
For older controls in CNC machinery, an “I”, “J”, and “K” are used to specify location of the center point of the arc.