FB_ControlAxisByPosCnc - General Information

Overview

Type:	Function block
Available as of:	V1.0.3.0
Inherits from:	-
Implements:	-

Description

This function block is used to write target positions to a drive and to monitor for gaps.

WARNING
	UNINTENDED EQUIPMENT OPERATION Do not execute the function blocks MC_SetPosition and MC_Superimposed while the function block FB_ControlAxisByPosCnc is running (output bBusy = TRUE). Verify that the values for the inputs fGapVelocity, fGapAcceleration, fGapDeceleration, fGapJerk, fMaxAcceleration, fMaxDeceleration, and fMaxVelocity of the function block FB_ControlAxisByPosCnc are within the permissible ranges of the mechanical system of your machine. Failure to follow these instructions can result in death, serious injury, or equipment damage.

WARNING

UNINTENDED EQUIPMENT OPERATION

Do not execute the function blocks MC_SetPosition and MC_Superimposed while the function block FB_ControlAxisByPosCnc is running (output bBusy = TRUE).
Verify that the values for the inputs fGapVelocity, fGapAcceleration, fGapDeceleration, fGapJerk, fMaxAcceleration, fMaxDeceleration, and fMaxVelocity of the function block FB_ControlAxisByPosCnc are within the permissible ranges of the mechanical system of your machine.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Compensation Movement

If the sequence of target positions sent to the axis requires velocities higher than the set limits, the output bStopIpo of the function block is set to TRUE. This stops the connected SMC interpolator and allows the axis to perform a compensation movement with the acceleration, velocity, deceleration, and jerk values set at the corresponding inputs to remain within the physical limits of the axis. Once the compensation movement is completed, the output bStopIpo is reset to FALSE and the initial movement can be resumed.

Interface

Input	Data type	Description
Axis	MOIN.IF_axis	Reference to axis. See Motion Interface Library Guide for details.
iStatus	SM3_CNC.SMC_INT_STATUS	Sets the status of an SMC_Interpolator instance. It is connected to the output iStatus of the function block SMC_Interpolator (see SM3_CNC.SMC_INT_STATUS in the SM3 CNC Library Guide).
bEnable	BOOL	Default value: FALSE If this input is set to TRUE, the function block starts to control the axis. FB_ControlAxisByPosCnc remains active until one of the following conditions is true: The function block is interrupted by another motion function block. An error is detected. Enable is set to FALSE. In this case, the function block stops the ongoing movement before releasing the control of the axis. If the input remains FALSE for three consecutive cycles while ET_Result is ExecuteWithGap or ExecuteWithoutGap, the function block transitions to the state Halt.
bAvoidGaps	BOOL	Default value: TRUE If this input is set to TRUE, position and velocity are monitored. If the velocity exceeds the limit, the output bStopIpo is set to TRUE and the axis moves to the position at the input fSetPosition according to the values set via the inputs fGapVelocity, fGapAcceleration, fGapJerk, and fGapDeceleration. After that, the output bStopIpo is reset to FALSE.
fSetPosition	LREAL	Value range: Any LREAL value Default value: 0 Target position for the axis. Typically, this input is connected to an output of a transformation function block, or directly to an output of a function block SMC_Interpolator.
fGapVelocity	LREAL	Value range: Any positive LREAL value Default value: 1 Velocity for bridging of gap.
fGapAcceleration	LREAL	Value range: Any positive LREAL value Default value: 1000 Acceleration for bridging of gap.
fGapDeceleration	LREAL	Value range: Any positive LREAL value Default value: 1000 Deceleration for bridging of gap, and for stopping if bAvoidGaps is FALSE and bEnable is set to FALSE.
fGapJerk	LREAL	Value range: Any positive LREAL value and 0 Default value: 0 Jerk for bridging of gap, and for stopping if bAvoidGaps is FALSE and bEnable is set to FALSE.
fMaxVelocity	LREAL	Value range: Any positive LREAL value Default value: 1000 Maximum velocity of axis.
fMaxAcceleration	LREAL	Value range: Any positive LREAL value Default value: 100000 Maximum acceleration of axis.
fMaxDeceleration	LREAL	Value range: Any positive LREAL value Default value: 100000 Maximum deceleration of axis.

Output	Data type	Description
bBusy	BOOL	TRUE = Execution of function block is not finished. FALSE = Execution of function block is finished.
bCommandAborted	BOOL	TRUE = Command has been aborted by a different command. FALSE = Command has not been aborted by a different command.
bError	BOOL	TRUE = Error detected in execution of the function block. TRUE = No error detected in execution of the function block.
q_etResult	ET_Result	Indicates the type of diagnostics information. If bError is FALSE: Status information. If bError is TRUE: Information on detected error.
q_sResultMsg	STRING(80)	Provides a diagnostics message.
bStopIpo	BOOL	TRUE = FB_ControlAxisByPosCnc has detected a gap condition and the axis performs a movement to close the gap. Connect this output to the input EmergencyStop of SMC_Interpolator so that the interpolator waits until the axis has repositioned. FALSE = No gap condition detected by FB_ControlAxisByPosCnc