AxisPlcOpenMc

Namespace

ZEquipment

Extends

ZEquipment.Axis

AxisPlcOpenMc

Inherited Properties

ActualMotionState

Booted

Busy

Done

DriveEnabled

DrivePowered

DriveStateAsString

Error

Manufacturer

Parked

Inherited Methods

EnableDriveAsync

ErrorId

ErrorMessage

ErrorSource

Name

ParametrizeAsync

ParkAsync

RegisterListener

ResetErrorAsync

StopAsync

TraceErrorStack

Implements

IAxisHoming

IAxisMovePosition

IAxisMoveVelocity

IAxisFeedbackPosition

IAxisFeedbackVelocity

IAxisFeedbackCurrent

IAxisHalt

IAxisVelocityFeedrate

IAxisBase

IObject

IBootable

IError

FUNCTION_BLOCK AxisPlcOpenMc EXTENDS ZEquipment.Axis IMPLEMENTS ZEquipment.IAxisHoming, ZEquipment.IAxisMovePosition, ZEquipment.IAxisMoveVelocity, ZEquipment.IAxisFeedbackPosition, ZEquipment.IAxisFeedbackVelocity, ZEquipment.IAxisFeedbackCurrent, ZEquipment.IAxisHalt, ZEquipment.IAxisVelocityFeedrate, ZEquipment.IAxisBase, ZCore.IObject, ZCore.IBootable, ZCore.IError (
 [output] Diagnostics : ZCore.DiagnosticMessage)

This function blocks implements the general axis interfaces by utilizing motion controllers that are conform to the PLCopen standard. This is the goto axes implementation of the Zeugwerk Framework if you want to control your axes via NC Motion (TwinCAT) or Softmotion (Codesys).

Internally, AxisPlcOpenMc uses MC function blocks (standardized by the PLCopen) to implement the Zeugwerk Framework's axis interfaces (i.e. IAxisBase, IAxisMovePosition, ...).

However, this implementation is not only a simple wrapper of MC function blocks, it also simplifies the usage of said function blocks. Any method that is suffixed with Async will automatically take care of fulfilling its preconditions. For instance, a call to MoveAbsoluteAsync will automatically execute an error reset if neccessary and will power on the axis.

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Reset any drive errors if there are still errors, which have not been acknowledged yet
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis
• Enable the drive if it is not enabled yet

Besides implementing the axis interfaces of the Zeugwerk Framework, this function block offers some methods, which are specific to PLCopen (e.g. TwinCAT NC)

• Use AxisRef to get hold of the AXIS_REF object. This is mainly needed for multiaxes applications (i.e. gantry), since AxisPlcOpenMc is meant for convienent single axis usage only.
• (Twincat NC only) Use VelocityFeedrate to overwrite all velocities in percent.

Outputs

Diagnostics DiagnosticMessage

Constructor

FB_init

METHOD FB_init (
 [input] bInitRetains : BOOL,
 [input] bInCopyCode : BOOL,
 [input] parent : ZCore.IManagedObject) : BOOL

Inputs

bInitRetains BOOL

if TRUE, the retain variables are initialized (warm start / cold start)

bInCopyCode BOOL

if TRUE, the instance afterwards gets moved into the copy code (online change)

parent IManagedObject

Returns

BOOL

Properties

ActualCurrent

PROPERTY ActualCurrent : LREAL

Returns the actual current, which is used by the drive. The value returned is usually given in % of the nominal current.

Property Value

LREAL

ActualFollowingError

PROPERTY ActualFollowingError : LREAL

Returns the deviation between the nominal position of the axis, according to the drive internal profile generator, to the actual position. The actual position is usually related to a position encoder or resolver 1 or 2 depending on which encoder is used for the actual movement. The value returned is given in drive positional-unit, which is usually millimeters or degrees, respectively.

By summing up the values of ActualFollowingError and ActualPosition it is possible to calculate the nominal position of the profile generator.

Property Value

LREAL

ActualPosition

PROPERTY ActualPosition : LREAL

Returns the actual position of the axis, which is usually related to a position encoder or resolver. The value returned is given in drive positional-unit, which is usually millimeters or degrees, respectively.

Property Value

LREAL

ActualSafetyState

PROPERTY ActualSafetyState : AxisSafetyStateFlags

This property can be used to test if a given safety feature of a drive is currently activated or not. Note that the property returns a "Flags" enumeration, which means that several bits of the returned value can be on at the same time.

Note

Retrieving the safety state of a drive is manufacturer specific.

• Some drives may not support some of the features that are depicted in the returned value (some bits may always be 0).
• Generic axes implementation (i.e. AxisPlcOpenMc) of the Zeugwerk Framework usually do not return the correct safety state of the drive. In doubt refer to the documentation of your specific implementation.

Warning

Since this axis implementation is generic it can not correctly return the safety state of the drive. The return value will always be 0 (no bit of the returned type is set)

Property Value

AxisSafetyStateFlags

ActualVelocity

PROPERTY ActualVelocity : LREAL

Returns the actual velocity of the axis, which is usually calculated by using a position encoder or resolver. The value returned is given in drive velocity-units, which is usually millimeters-per-seconds or degree-per-seconds, respectively. In contrast to speed, velocity is a signed value such that it can have a positive or negative sign.

Property Value

LREAL

Parameter

PROPERTY Parameter : IAxisPlcOpenMcParameter

This property returns an interface to the central parameterization entry point of an PlcOpen Mc Axis. Usually parameters are split in

• Booting parameters
• Drive parameters: homing parameters, positioning type and modulo settings can be accessed here
• Plc parameters: maximum speed and conversion parameters
• Simulation parameters: setting an initial (simulated) position, jerk and acceleration of the simulated trajectory

It is also possible to return the ParameterChannel interface to be able to access every parameter needed of an Axis PlcOpen Mc instance

Property Value

IAxisPlcOpenMcParameter

Referenced

PROPERTY Referenced : BOOL

This property can be used to test if an axis is referenced correctly. For axes that use an incremental encoder, this means that a homing procedure has been already been executed correctly. For axes that use an absolute encoder, this usually means that the encoder has been initialized correctly.

Read the documentation of your axes implementation (i.e. AxisPlcOpenMc) for more specifics.

Property Value

BOOL

Simulation

PROPERTY Simulation : BOOL

This property can be used to enable or disable simulation mode of this axis. Whenever the simulation flag is changed, the drive will automatically (re-)initialize by performing its booting sequence. Hence, it is possible to switch to simulation and back while the PLC is running. The simulated axis instance utilizes AxisSimulatedImpl, which in turn uses the Online-Trajectory-Generator to generate motion profiles.

Warning

Some PLCopen conform motion controllers (NC Motion) come with a built-in simulation mode on their side. This property will have no impact to the simulation mode of the motion controller. Thus, when setting up the motion controller, one can use a simulated (by the motion controller) axis instance, even if on=FALSE.

Property Value

BOOL

State

PROPERTY State : ZCore.ObjectState

Returns the object state of the axis object. This exposes if an object is still in its booting phase, had an error, or is busy executing an async action.

Property Value

ObjectState

VelocityFeedrate

PROPERTY VelocityFeedrate : LREAL

This property is used to adjust the actual commanded velocity by a feedrate factor. Provide values between 0.0 and 1.0 which leads to 0% of the commanded velocity all the way up to 100%. The Feedrate functionality is automatically enabled after first power on of a PlcOpen axis.

Property Value

LREAL

Methods

AxisRef

METHOD AxisRef () : REFERENCE TO ZPlatform.PlcOpenAxisRef

Returns

REFERENCE TO PlcOpenAxisRef

HaltAsync

METHOD HaltAsync (
 [input] startToken : ZCore.IStartToken)

By using this method the drive will stop with the same position profile (regarding jerk, acceleration and deceleration) as it is used to move the axis. Calling this method will beforehand automatically trigger the following sequences

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)

To check if the method could be started successfully, pass such an StartToken as a startToken. Then Assert this object or check for startToken.Error.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

HomingAsync

METHOD HomingAsync (
 [input] startToken : ZCore.IStartToken)

Use this method to start the homing prodedure of the axis.

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

Note

Although (servo) drives usually offer a comparable method for homing, it is hard to abstract all methods, which might be possible to use for specific drive manufactures. Therefore, the actual selection of a homing method can usually be found in specific implementations with a SetHomingMethod method (i.e. AxisStepperEL7031.SetHomingMethod.

Inputs

startToken IStartToken

(optional) object to check if the method was executed successfully - may be 0

IsAtPosition

METHOD IsAtPosition (
 [input] pos : LREAL,
 [input] window : LREAL) : BOOL

Use this method to check if an axis is at a specific location in a given window. Note that some implementation may not use the parameter window, but may rely on a drive internal position-window. In doubt, read the documentation of your axes implementation (i.e. AxisPlcOpenMc).

Inputs

pos LREAL

window LREAL

Returns

BOOL

MoveAbsoluteAsync

METHOD MoveAbsoluteAsync (
 [input] startToken : ZCore.IStartToken,
 [input] position : LREAL,
 [input] speed : LREAL)

Starts to move the axes to a specific position with a given velocity. The method utilizes the drive's profile generator, which may offer to adjust acceleration, deceleration and jerk as PDOs or SDOs as well. The latter parameters are usually vendor specific and thus are not part of the interface. Use the Parameter property of each specialised axis to adjust said values before calling this method. Calling this method will beforehand automatically trigger the following sequences

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Reset any drive errors if there are still errors, which have not been acknowledged yet
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis
• Enable the drive if it is not enabled yet

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

If a MoveAbsoluteAsync or MoveRelativeAsync command is currently being executed, calling this method can be used to overwrite the current move command. This is an exeception to the rule that this method should not be called while the axis is busy.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

position LREAL

Position in drive position units, usually millimeter or degree

speed LREAL

Speed in drive speed units, usually millimeter-per-second, or degree-per-second

MoveRelativeAsync

METHOD MoveRelativeAsync (
 [input] startToken : ZCore.IStartToken,
 [input] distance : LREAL,
 [input] speed : LREAL)

Starts to move the axes to a specific distance from its current position with a given velocity. The method utilizes the drive's profile generator, which may offer to adjust acceleration, deceleration and jerk as PDOs or SDOs as well. The latter parameters are usually vendor specific and thus are not part of the interface. Use the Parameter property of each specialised axis to adjust said values before calling this method. Calling this method will beforehand automatically trigger the following sequences

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Reset any drive errors if there are still errors, which have not been acknowledged yet
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis
• Enable the drive if it is not enabled yet

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

If a MoveAbsoluteAsync or MoveRelativeAsync command is currently being executed, calling this method can be used to overwrite the current move command. This is an exeception to the rule that this method should not be called while the axis is busy.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

distance LREAL

Position in drive position units, usually millimeter or degree

speed LREAL

Speed in drive spped units, usually millimeter-per-second, or degree-per-second

MoveVelocityAsync

METHOD MoveVelocityAsync (
 [input] startToken : ZCore.IStartToken,
 [input] velocity : LREAL)

Starts to move the axes a specific velocity. The method utilizes the drive's profile generator, which may offer to adjust acceleration, deceleration and jerk as PDOs or SDOs as well. The latter parameters are usually vendor specific and thus are not part of the interface. Use the Parameter property of each specialised axis to adjust said values before calling this method. Calling this method will beforehand automatically trigger the following sequences

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Reset any drive errors if there are still errors, which have not been acknowledged yet
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis
• Enable the drive if it is not enabled yet

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

If a MoveVelocityAsync command is currently being executed, calling this method can be used to overwrite the current move command. This is an exeception to the rule that this method should not be called while the axis is busy.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

velocity LREAL

velocity in drive velocity units, usually millimeter-per-second, or degree-per-second; for variable frequency drives rotations/minute are common

RebootAsync

METHOD RebootAsync (
 [input] startToken : ZCore.IStartToken)

Reboot of the axis, which means that the internal state is switched back to Booting. In practice, this switches the axis' fieldbus back to PREOP, writes all parameters to the drive and then switches back to OP. Internally this is achieved by parking the axis and then unparking it.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

SetLogger

METHOD SetLogger (
 [input] logger : ZCore.ILogger)

Use this method together with SetName to enable logging for this axis. Various methods of this implementation write log messages into the passed logger interface.

Note

Sometimes it is beneficial to disable logging by passing 0 to this method (e.g. for inputs or outputs which are switch very often).

Inputs

logger ILogger

SetName

METHOD SetName (
 [input] name : ZCore.ZString)

Sets the name of this object as it will show up in any log messages that is created by this object. The name set with this method should be relatable to the name of the input in the electrical plan of your automation project to identify the corresponding input properly.

Inputs

name ZString

SetSimulation

METHOD SetSimulation (
 [input] on : BOOL)

Inputs

on BOOL