SMC_GroupReadPathVelocity (FB)¶

FUNCTION_BLOCK SMC_GroupReadPathVelocity

This function block returns the path velocity of an axis group.

Any position or orientation lag (see PositionLag and OrientationLag outputs of MC_GroupReadStatus) is ignored. The dynamics are evaluated as if the axis group was following the path exactly.

This is an administrative FB, no movement is generated.

InOut:

Scope	Name	Type	Initial	Comment
Inout	`AxisGroup`	AXIS_GROUP_REF_SM3		Reference to a group of axes
Input	`Enable`	`BOOL`		Return the path dynamics of the axis group in the selected coordinate system while enabled.
	`CoordSystem`	`SMC_COORD_SYSTEM`	SMC_COORD_SYSTEM.MCS	Coordinate system. Note: for any static coordinate system, the result will be the same. For dynamic coordinate systems, the returned dynamics are relative to this coordinate system and will depend on the movement of the PCS. The coordinate system ACS is not allowed.
	`Source`	`MC_SOURCE`	MC_SOURCE.SAVE	Determines the source on which the path dynamics is based. For MC_SOURCE.ACT, the actual value received from the drive in this bus task cycle is used. For MC_SOURCE.SAVE, the value computed in the PLC in the previous cycle is used. For MC_SORUCE.SET, the value computed in the PLC in this cycle is used. Note 1: if the set values of the axis group are used (\|MC_SOURCE.SET\|), then it is recommended to call SMC_GroupUpdate and to update any dynamic coordinate systems before this function block is called. For example, if MC_TrackConveyorBelt is used, then the movement function block of the belt-axis should be called before.
	`TimeOffset`	`LREAL`		The time offset in seconds when to evaluate the path dynamics. Must be in [0, `fPlanningForecastDuration`]. `fPlanningForecastDuration` can be configured using SMC_TuneCPKernel. For time offsets > 0, the output will only be `Valid` if the `Source` is set to \|MC_SOURCE.SET\| the `TimeOffset` does not exceed the `CurrentPlanningForecast` reported by MC_GroupReadStatus. While MC_GroupHalt or MC_GroupStop are active, valid path dynamics can only be obtained for TimeOffset = 0.
Output	`Valid`	`BOOL`		`TRUE` if valid outputs are available
	`Busy`	`BOOL`		The FB is not finished
	`Error`	`BOOL`		Signals that an error has occurred within the function block
	`ErrorID`	`SMC_ERROR`		Error identification
	`PathVelocity`	`LREAL`		Path velocity of the group in the given coordinate system