MC_MachRegist

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 Function BlockClosed A function block groups an algorithm and a set of private data. It has inputs and outputs. - Enables Mark-to-Machine registration.

Inputs

Input

Data Type

Range

Unit

Default

Description

En

BOOL

0, 1

N/A

No default

On the rising edgeClosed A rising edge is the transition of a digital signal from low to high. It is also called positive edge, request to enable registration.

Axis

AXIS_REF

The range of .AXIS_NUM is [1, 256]

N/A

N/A

Axis whose position is used to determine a good mark.

TriggerInput

TRIGGER_REF

No range

N/A

No default

Structure specifying the fast inputClosed The inputs are taken into account at each cycle depending on the system periodicity (for example each millisecond). Under certain circumstances this can be insufficient when more accuracy is needed, or if a quick response is required from the system. To fill the gap, a drive may have some Fast Input connections (generally one or two). When an event happens that triggers a Fast Input (e.g. when a sensor sends a rising edge), the detection of a signal occurs faster (which can be 1000 times more accurate than the system periodicity). Then the timestamp associated with this input can be provided to the IPC to take corrective action.

The structure elements are:

DirectionINT

Range = 1, 5.

  • 1 = Rising edge.
  • 2 = Falling edge.
  • 3 = N/A
  • 4 = Toggle between both, falling edge first.
  • 5 = Toggle between both, rising edge first.

InputID INT

Range = 0, 1

  • 0 = Touch Probe 1 / Capture Engine 0
  • 1 = Touch Probe 2 / Capture Engine 1

TrigIDINT

Range = 0, 256.

  • The axis number of the fast input.
  • 0 (zero) indicates this trigger axis is to be the same as the Axis input.

  • TrigMode INT (TriggerInput.TrigMode) is not presently supported by this function.

Distance

LREAL

  • When converted to feedback units, the range is [-251, 251-1].
  • This value must have the same sign as Ignore.

User units

N/A

  • This is the expected distance between good marks.
  • Along with Tolerance and Ignore, this value is used to determine if the mark detected by the fast input is a good mark.

Tolerance

LREAL

When converted to feedback units,
the range is [0 , 251-1].

User units

N/A

This value specifies the distance, plus or minus, about Distance to determine if the mark detected by the fast input is a good mark.

Ignore

LREAL

  • When converted to feedback units, the range is [-251, 251-1].
  • This value must have the same sign as Distance.

User units

N/A

This value specifies the distance after the previous good mark in which any detected marks are ignored.

Target

LREAL

When converted to feedback units,
the range is:

  • [-251,251-1] if PosAxis' rollover value is zero.
  • [0, PosAxis' Rollover Value] if PosAxis' rollover value is non-zero (i.e., ≥ 0 < PosAxis' Rollover Value).

User units

N/A

  • This is the target position.
  • This position is compared to the actual position captured by the fast input to determine the amount of registration compensation to apply.

Position

LREAL

When converted to feedback units,
the range is:

  • [-251,251-1] if PosAxis' rollover value is zero.
  • [0, PosAxis' Rollover Value] if PosAxis' rollover value is non-zero (i.e., ≥ 0 < PosAxis' Rollover Value).

User units

N/A

  • The position the axis is set to when a good registration mark occurs.
  • If the Inhibit Reference on Good Mark option is specified for the Option argument, this argument is not used.
    • The position of the axis is not changed when a registration mark is encountered.

PosAxis

AXIS_REF

The range of .AXIS_NUM is [1, 256]

N/A

N/A

The position of this axis at the time the fast input occurs is compared to the Target position.

This comparison determines the amount of registration compensation to apply.

CompAxis

AXIS_REF

The range of .AXIS_NUM is [1, 256]

N/A

N/A

The calculated registration compensation is applied to this axis.

PosTolerance

LREAL

When converted to feedback units, the range is [-251, 251-1].

User units

N/A

This value specifies the distance, plus or minus, about the Target position to determine if the position is accepted and the compensation value is calculated and applied.

RatioNumerator

DINT

When converted to feedback units,
the range is [1, 4294967295].

User units

N/A

  • This value is typically the number of User Units of CompAxis motion for one product cycle.
  • This value is used with RatioDenominator to create a conversion factor for calculating the compensation value when PosAxis and CompAxis are different axes.

RatioDenominator

DINT

When converted to feedback units,
the range is [1, 4294967295].

User units

N/A

  • This value is typically the number of User Units of PosAxis motion for one product cycle.
  • This value is used with RatioNumerator to create a conversion factor for calculating the compensation value when PosAxis and CompAxis are different axes.

Options

UINT

See the MC_MachRegist Options Table.

N/A

N/A

  • Each bit enables / disables an option.
  • The MC_MachRegist Options Table defines the bits.
  • Any bits not defined are reserved.
  • The third bit, 0004H, must be 0 (zero).

Outputs

Output

Data Type

Range

Unit

Description

RegistOn

BOOL

No range

N/A

Indicates registration is activated.

Aborted

BOOL

No range

N/A

Indicates registration has been terminated by MC_StopRegist.

Error

BOOL

No range

N/A

Indicates an invalid input was specified or the registration was terminated due to an error.

ErrorID

INT

No range

N/A

Remarks

  • It is used on any servo or digitizing axis and with any move type.
  • It is used most frequently in master/slave applications.

Used with ...

Effect

Non-slave moves

Resets the axis position when a good mark is captured by the fast input.

Slave moves

Applies a compensation offset to correct for the difference between the target position and the measured position.

This provides the ability to compensate for product or process inconsistencies, provides a system that remains synchronized with no accumulated error, and maintains repeatable accuracy throughout the process.

Transition and Registration

  • A positive transition of the En input starts registration.
    • The application may change the registration parameters while registration is active by changing the input values and causing another positive transition of the En input.
    • The function block then reads and applies the new values.
  • The axis number at the Axis input indicates the axis whose position, at the fast input, is used to determine if the mark is a good mark.

Distance, Tolerance, and Ignore Inputs

  • The Distance, Tolerance, and Ignore inputs are used to determine whether or not the registration mark is good.
    • For a mark to be recognized as good, it must be outside of the Ignore distance and the correct Distance from the previous mark +/- the Tolerance window.
    • A mark is bad if it occurs outside of the “good tolerance band” and is not ignored.
    • Both good marks and bad marks are recognized as marks, ignored marks are not recognized.
    • If all marks are to be recognized as good marks, enter 0 (zero) at both Distance and Tolerance.
  • The Distance value defines the distance between good marks.
    • In Clear Lane and Product registration the Distance input value is typically the same as the Target input value.
    • In Print registration, the Distance is typically not the same as Target.
  • The Tolerance value is the distance, plus and minus, about Distance.
    • Marks detected in this window are good marks and registration occurs.
    • Marks detected outside this window and outside the Ignore band, are bad marks and registration does not occur.
    • This window should be large enough to allow for the worst case error in the distance between the previous mark and the current mark.
  • The Ignore value defines the distance from the previous mark where all marks detected by the fast input are ignored.
    • This is crucial when registering products that do not have Clear Lane registration marks.

Target Input

  • The Target input is the expected target position that is used to calculate how much registration compensation is to be applied when a registration mark is considered good.
    • When a good mark is detected, the position of the PosAxis is compared to the Target position to calculate a correction.
    • The registration correction is only applied with master/slave move types.

Position and Option Inputs

Position Inputs

  • The Position input is the position value the registration Axis position is reset to when a good registration mark is detected.
    • When a good mark occurs, the position of the PosAxis is compared to the Target position.
      • This comparison is used to calculate the amount of registration compensation to apply to the CompAxis.
        • Registration compensation is applied to the axis specified at the CompAxis input under these conditions:
        • If CompAxis is a master axis, the compensation is applied to the master offsets of all its slaves.
          • This shifts the master’s position as seen by its slaves.
        • If CompAxis is executing a slave move (e.g., MC_GearIn or MC_CamIn), the compensation is applied directly to the axis.
    • The PosTolerance input is the distance, plus and minus, about the Target position used to determine if compensation is applied.
      • When a good mark occurs, the position of the PosAxis axis is checked to see if it lies in the window defined by PosTolerance.
        • If it is in the window, compensation is applied.
        • If it is outside the window, compensation is not applied even though a good mark was found.
    • If PosAxis and CompAxis are different axes, the RatioNumerator and RatioDenominator inputs define the conversion factor for calculating the compensation value.
      • This is needed because the amount of error between actual and target positions is determined by the PosAxis's position and the compensation is applied to the CompAxis.
      • The RatioNumerator should typically be the number of User Units of CompAxis motion for one registration cycle.
      • The RatioDenominator should typically be the number of User Units of PosAxis motion for one registration cycle.
      • If PosAxis and CompAxis are the same, RatioNumerator and RatioDenominator should be the same value, thus resulting in a 1:1 ratio.

Option Inputs

  • The Option input defines various modes of operation for registration.
    • The first bit, 0001H, selects Absolute or Resetting.
      • This refers to the way the second mark and all subsequent marks are determined to be good marks.
      • With both registration schemes, the very first detected mark is the starting point.
      • With Resetting registration, when the next mark is detected, the position of that mark becomes the starting point for the next good mark detection calculation and so on.
        • The starting point is reset with each good or bad mark.
          • This allows the product to re-synchronize, if necessary, due to process issues (e.g., product shift) etc.
        • Absolute registration determines all good marks based on the very first mark.
          • The position of the second and each subsequent mark is compared to an integer multiple of Distance from the very first mark.
          • This method insures the product always registers to a known fixed distance.
      • The third bit, 0004H, must be 0 (zero).
        • Mark-to-machine registration requires time-based capture.

Figure 6-258: MC_MachRegist

MC_MachRegist Options Table

Hexadecimal

Decimal

Option

Description

0001 H

1

Absolute/Resetting

0 = Resetting, 1 = Absolute

0002 H

2

Reserved

0

0004 H

4

Time/position based capture

0 = time based capture, 1 = position based capture

0008 H

8

Inhibit Reference on Good Mark

0 = Perform reference, 1 = inhibit reference

When this bit is set, the Position function block argument is unused and the axis position is not changed when a registration mark is encountered.

0010H

16

Inhibit Master Compensation

0 = Perform Master Compensation, 1 = Inhibit Master Compensation

0020H

32

Inhibit Slave Compensation

0 = Perform Slave Compensation, 1 = Inhibit Slave Compensation.

FBD Language Example

FFLD Language Example

IL Language Example

CAL Inst_MC_MachRegist( ActivateReg, Axist2, Trig1, 360, 5, 90, 180, 0, Axis2, Axis2, 5, 1, 1, 0 )

ST Language Example

Inst_MC_MachRegist( ActivateReg, Axist2, Trig1, 360, 5, 90, 180, 0, Axis2, Axis2, 10, 1, 1, 0 );

See Also