SMC_ToolLengthCorr (FB)¶

FUNCTION_BLOCK SMC_ToolLengthCorr

This function block compensates the tool length offset (e.g. of a drill, commanded with G43) relative to the tool holder flange. In other words, it creates a shifted path by subtracting the given tool length offset vector adToolLength from the machine’s flange to the TCP from the set position pi, taking into account its current orientation. The orientation of the flange’s coordinate system given by piIn.dA, piIn.dB, piIn.dC gets interpreted according to eOriConv. The following illustration shows a drill mounted to the flange with offset. Note, that in this common example the tool length points into negative z-direction.

../../../_images/SMC_ToolLengthCorr_1.png

With bForwardTrafo set to FALSE (default) this function block is intented to be used between SMC_Interpolator and a backward transformation:

V_flange= V_TCP- R_ABC * V_tool

With bForwardTrafo set to TRUE this function block can also be used with a forward transformation:

V_TCP= V_flange+ R_ABC * V_tool

Note

This function block does not perform a tool radius correction. Furthermore the tool length should not be changed while a tool radius correction is active, since this would lead to a jump in the path.

Note

If the tool length correction creates a path shifted in a 3D direction without having activated 3D mode, SMC_NCDecoder signals error SMC_SMB_ONLY_3DMODE.

InOut:

Scope	Name	Type	Initial	Comment
Inout Const	`pi`	SMC_PosInfo		The set position as calculated by SMC_Interpolator. The orientation A/B/C of the tool is expected in degrees.
Inout Const	`adToolLength`	ARRAY [0..2] OF LREAL		The tool lenght offset vector V_tool from flange V_flange to TCP V_TCP.
Input	`eOriConv`	SMC_ORI_CONVENTION	SMC_ORI_CONVENTION.ZYZ	Defines the way the orientation `piIn.dA`, `piIn.dB`, `piIn.dC` is interpreted. If the value is SMC_ORI_CONVENTION.ADDAXES, then no tool length correction will be performed.
Input	`bForwardTrafo`	`BOOL`	FALSE	If TRUE, the calculated set position `piOut` is the input of the forward transformation instead of the backward transformation
Output	`piOut`	SMC_PosInfo