Camming

	Core function is not supported by inverter axes This core function is not supported by inverter axes. Any use will report DEVICE_NOTINIT and trigger an error message.

The property provides two options: Camming.Pos for position camming and Camming.Velo for velocity camming. To do this, two classes of the same type are instantiated, but with different parameterizations.

All these functions belong to the group of statically controlled core functions.

Both types of camming use a default value to identify a control value within a camming lookup table. For more information, see CammingLookUp.

Any useful information can serve as a default value. Common options are a time (LREAL variable that starts with zero and is cyclically updated by adding the cycle time of the PLC tasks) or the position of another axis.

WARNING

Unexpected responses of the controlled axis

Unsuitable default values or table points can lead to unexpected reactions of the controlled axis. This may result in risk of accident or damage.

Using a camming requires several steps:

A camming lookup table must be instantiated. There is no rule for the number of these tables. A table used once can be used again at a later time by repeating the following steps.
The table must be defined by loading the table points. Make sure that the point data corresponds to the camming type (position, velocity) for which it is to be used.
The properties of the table must be updated.
The table must be assigned to the camming with the method SetLookupinterface(). At this time, camming must not be commanded.
An initial default value must be specified with the SetGuidingValue() method.
At the right time use DoCamming(TRUE) to enable the function. Make sure that the axis is in a situation (position, velocity) that matches the situation of the camming table.
Make sure that the default value is updated cyclically.
At the right time use DoCamming(FALSE) to disable the function. Pay attention to the situation (position, velocity) of the axis.

Syntax:

FUNCTION_BLOCK FB_Camming EXTENDS FB_CorefunctionFeedback

Properties

Name	Type	Access	Description
InitState	BOOL	Get, Set	The core function is not completely and successfully initialized.
FB_Camming
Overrun	BOOL	Get	TRUE if the current default value is not within the range of the camming lookup table.
Synchronize	BOOL	Get, Set	With Synchronize=FALSE the axis should follow every setpoint change immediately. A TRUE requires the axis to follow setpoint changes with respect to the dynamic limit parameters.
Synchronized	BOOL	Get	TRUE if Synchronize=TRUE and the setpoint changes are within the limits of the dynamic parameters of the axis.
UseAsPosition	BOOL	Get, Set	This property defines the camming rule. A TRUE causes the core function to act as a position camming. A FALSE will cause it to act as a velocity camming. This property is set during startup. The application must not change its setting.
FB_CorefunctionFeedback
AbortedState	BOOL	Get, Set	Signals the abort of a command by another Corefunction.
BusyState	BOOL	Get, Set	Signals the active execution of a command.
DoneState	BOOL	Get, Set	Signals the successful execution of a command.
IdleState	BOOL	Get, Set	The Corefunction is ready for operation and commandable.
IsCommanded	BOOL	Get	Signals the pending of a command.
FB_Corefunction
[`INTERN`] AxisState	E_AxisState	Get, Set	The current state of the axis state machine.
[`INTERN`] Connected	BOOL	Get	The Corefunction is connected to an axis.
[`INTERN`] CycleTime	LREAL	Get, Set	The cycle time of the PLC task from which the method `Cyclic()` of the Corefunction is executed.
[`INTERN`] CycleTimeValid	BOOL	Get, Set	A TRUE indicates that the `CycleTime` of the Corefunction is defined.
FailedState	BOOL	Get, Set	If IsActivated is TRUE at the same time: Signals the failure of an accepted command. If IsActivated is FALSE at the same time: Signals the rejection of a command.
HasFeedback	BOOL	Get	The core function has responded to a pending command.
IsActivated	BOOL	Get	The core function has an accepted command pending.
IsLocalCmd	BOOL	Get	Signals that the axis is assigned with a command of this core function.
[`INTERN`] NextCore	I_Corefunction	Get, Set	This property is part of the execution chain and must not be affected by the application task.
[`INTERN`] OnlineChangeMark	BOOL	Get, Set	The axis uses this property to signal an Online Change to the Corefunction.
ReadyState	BOOL	Get, Set	The Corefunction is ready for operation, but is not commandable at this time. Possible reasons are: - The axis is not enabled. - Another Corefunction is active. - The Corefunction does not support any commands.

Methods

Name	Description
[`INTERN`] Cyclic()	This method is called cyclically by the axis.
FB_Camming
DoCamming()	This method is used to enable and disable the core function.
SetGuidingValue()	This method is used to update the default value.
SetLookupInterface()	This method must be used to connect a camming table.
FB_Corefunction
[`INTERN`] ApplyCommand()	Applies the command to the axis.
[`INTERN`] ClearStates()	Clears up some of the possible states.
[`INTERN`] DoReset(`bExecute`)	This method is called when the axis is reset.
[`INTERN`] RemoveCommand()	Removes the command from the axis.

Interfaces

Type	Description
I_Corefunction	Standard interface on FB_Corefunction.
I_Camming	Standard interface on FB_Camming
I_CorefunctionFeedback	Standard interface on FB_CorefunctionFeedback.

Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT v3.1.4024.35	PC or CX (x64, x86)	Tc3_PlasticFunctions v3.12.4.26 or higher

Further Information