IF_ExternalPositionSource - WriteRefValues (Method)

Overview

Type	Method
Available as of:	V2.12.1.0

This chapter provides information on:

Task
Description
Interface
Diagnostic Message
Implementation Example

Task

Writing the reference values for the configured robot components cartesian, orientation and auxiliary axes.

Description

This method is called from the FB_Robot every Sercos cycle if the robot is enabled.

With the method WriteRefValues(…), the reference values of the robot components cartesian, orientation, and auxiliary axes can be calculated and passed to the robot.

NOTE: CAM profiles providing reference position values to the robot must be contiguous in terms of position. In case of a periodic CAM profile, the start and the end position of the CAM must be identical.

The reference values that are passed are then forwarded to the configured transformation to calculate the robot axes positions. The calculated axes positions are forwarded to the axes in the same Sercos cycle.

Reference values can be passed for configured and supported robot components only. If a value for an unconfigured robot component is passed to the robot, the robot reports a diagnostic message.

The diagnostic outputs can be used to forward an exception from this method to the robot. The forwarded exception is reported by the FB_Robot and the robot axes are stopped by a ControllerStop.

Interface

Output	Data type	Description
q_etDiag	GD.ET_Diag	General, library-independent statement on the diagnostic. A value not equal to ET_Diag.Ok corresponds to a diagnostic message.
q_etDiagExt	ET_DiagExt	POU-specific output for the diagnostic. q_etDiag = ET_Diag.Ok -> Status message q_etDiag <> ET_Diag.Ok -> Diagnostic message
q_sMsg	STRING[80]	Event-triggered message that gives additional information on the diagnostic state.
q_stRefPositionTCP	PDL.ST_Vector3D	Reference position of TCP.
q_stRefOrientationTCP	PDL.ST_Vector3D	Reference position of orientations.
q_etRefArmConfiguration	ET_ArmConfiguration	Reference arm configuration of the robot.
q_alrRefPositionAuxAx	ARRAY [ET_RobotComponent.AuxAx1... (ET_RobotComponent.AuxAxAll + Gc_udiMaxNumberOfAuxiliaryAxes)] OF LREAL	Reference position of auxiliary axes.

Diagnostic Messages

q_etDiag	q_etDiagExt	Enumeration value	Description
ExecutionAborted	AuxiliaryAxisNotConfigured	127	The auxiliary axis is not configured.
ExecutionAborted	ComponentNotConfigured	198	The component is not configured.
ExecutionAborted	ArmConfigurationInvalid	200	The arm configuration is invalid.

ArmConfigurationInvalid

Enumeration name:	ArmConfigurationInvalid
Enumeration value:	200
Description:	The arm configuration is invalid.

Issue	Cause	Solution
Writing the reference values for the configured robot components was unsuccessful.	A reference value for the arm configuration was passed to the robot. The robot does not support the arm configuration passed or does not support any arm configuration.	Ensure that no reference value for the arm configuration is passed to the robot in the case that the robot does not support an arm configuration, or ensure that a valid reference value for the arm configuration is passed to the robot in the case that it does.

AuxiliaryAxisNotConfigured

Enumeration name:	AuxiliaryAxisNotConfigured
Enumeration value:	127
Description:	The auxiliary axis is not configured.

Issue	Cause	Solution
Writing the reference values for the configured robot components was unsuccessful.	A reference value for an unconfigured auxiliary axis was passed to the robot.	Ensure that no reference value for an unconfigured robot component is passed to the robot.

ComponentNotConfigured

Enumeration name:	ComponentNotConfigured
Enumeration value:	198
Description:	The component is not configured.

Issue	Cause	Solution
Writing the reference values for the configured robot components was unsuccessful.	A reference value for an unconfigured Cartesian component or orientation was passed to the robot.	Ensure that no reference value for an unconfigured robot component is passed to the robot.

Implementation Example

Declaration:

METHOD WriteRefValues
VAR_OUTPUT
  q_etDiag                : GD.ET_Diag := GD.ET_Diag.Ok;
  q_etDiagExt             : ROB.ET_DiagExt := ROB.ET_DiagExt.Ok;
  q_sMsg                  : STRING[80];
  q_stRefPositionTCP      : PDL.ST_Vector3D;
  q_stRefOrientationTCP   : PDL.ST_Vector3D;
  q_etRefArmConfiguration : ROB.ET_ArmConfiguration;
  q_alrRefPositionAuxAx   : ARRAY [ROB.ET_RobotComponent.AuxAx1..
                            ROB.ET_RobotComponent.AuxAxAll + 
                            ROB.Gc_udiMaxNumberOfAuxiliaryAxes)] 
                            OF LREAL;
END_VAR
VAR
  etAuxAx                 : ROB.ET_RobotComponent;
END_VAR

Implementation:

// Implementation of the external position source.
// Handover the reference values of the configured robot components.
// Do not write outputs of not configured or not supported robot
   components.
//********************************************************************
// Reference values of the Tool Center Point
//********************************************************************

// q_stRefPositionTCP.lrX := ...;
// q_stRefPositionTCP.lrY := ...;
// q_stRefPositionTCP.lrZ := ...;

//********************************************************************
// Reference values of the Tool Center Point
//********************************************************************

// q_stRefOrientationTCP.lrX := ...;
// q_stRefOrientationTCP.lrY := ...;
// q_stRefOrientationTCP.lrZ := ...;

//********************************************************************
// Reference value of the arm configuration
//********************************************************************

// q_etRefArmConfiguration := ...;

//********************************************************************
// Reference values of the auxiliary axes
//********************************************************************
// FOR etAuxAx := ROB.ET_RobotComponent.AuxAx1 TO
// (ROB.ET_RobotComponent.AuxAxAll + ROB.Gc_udiMaxNumberOfAuxiliaryAxes) 
   DO
//
//   q_alrRefPositionAuxAx[etAuxAx] := ...;
//
// END_FOR