G91 cnc意思
"G91" is a command in CNC (Computer Numerical Control) programming that specifies the relative positioning mode. In this mode, the machine tools move a specified distance relative to the current position. For example, if you issue a G91 command and then move the tool 1 inch to the right, the tool will actually move 1 inch to the right from its current position.
In contrast, the absolute positioning mode (which is the default mode in most CNC systems) uses the G90 command. In this mode, the machine tools move to an absolute position specified in the program, regardless of the current position of the tool.
The G91 command is often used in CNC programming to perform incremental movements, which can be useful for drilling holes in a straight line or for other operations where you need to move the tool a specific distance relative to its current position.