Velocity curve in the contouring section

Depending on axis parameterisation and the application, it may be necessary to influence the velocity curve in the contouring section. In the default definition, the contouring section is travelled at maximum permissible path velocity. If the axes have strongly different dynamics, this could lead to an unacceptable excitation of vibrations in the machine because path velocity is adjusted in the contouring section.

The characteristic in the contouring section can be adjusted by specific control commands in the NC command #CONTOUR MODE.

In the example below, the block transition from N6 to N7 is contoured by polynomials which are moved in the contouring section at maximum velocity, i.e. the velocity is adjusted here by different axis dynamics. The transition from N9 to N10 is also contoured but without any velocity adjustment. This leads to a constant path velocity in the contouring section.

Programing Example

Velocity curve in the contouring section

%poly_const_speed

N0003 #SLOPE[TYPE=TRAPEZ]

N0004 G1 X0 Y0 Z0 F8000

N0005 #CONTOUR MODE [CONST_VEL=0]

N0006 X100 G61

N0007 Y100

N0008 #CONTOUR MODE [CONST_VEL=1]

N0009 X0 G61

N0010 Y0

N0020 M30