Axis positions in the ACS

Target position (ACS)

Description

Target position in the current NC block, ACS. This represents the target position of the program coordinate system referred to the axes. It is valid only as long as no transformation is active. Currently, the target position is not transformed back onto the axes.

Signal flow

CNC → PLC

ST path

gpAx[axis_idx]^.lr_state.end_position_acs_r

Data type

DINT

Unit

0,1 µm

Access

PLC reads

Actual position (ACS)

Description

Actual position of the current cycle in the axis coordinate system

Signal flow

CNC → PLC

ST path

gpAx[axis_idx]^.lr_state.current_position_acs_r

Data type

DINT

Unit

0,1 µm

Access

PLC reads

Command position (ACS)

Description

Command position of current cycle in the axis coordinate system

Signal flow

CNC → PLC

ST path

gpAx[axis_idx]^.lr_state.active_position_acs_r

Data type

DINT

Unit

0.1 µm

Access

PLC is reading

Command position (ACS) from interpolator

Description

Command position in the axis coordinate system which is refreshed each interpolator cycle.

Signal flow

CNC → PLC

ST path

gpCh[channel_idx]^.bahn_state.coord_r[axis_idx].acs_position_r

Unit

0.1 µm

Data type

DINT

Access

PLC is reading

Position offset

Description

Display of the current offset of the absolute position between the position controller axis (real physical axis) and the interpolator axis (logical axis) currently linked in the axis coordinate system.

The display here shows an offset between the interpolator position and the position controller position caused by the use of functions such as “jog of path” (see [FCT-C15].

The offset displayed contains no offsets caused by zero offsets, for example.

Signal flow

CNC → PLC

ST path

gpAx[axis_idx]^.lr_state.position_offset_r

Data type

DINT

Unit

0.1 µm

Access

PLC is reading

Look ahead command positions

Description

This array allows the user to access a limited number of future interpolator command values in the PLC. For example, this can be used to carry out monitoring in the PLC based on a future axis movement that has not yet been executed.

The delay is the delayed position output between the interpolator and position controller and therefore the effectiveness on the drive.

The maximum possible index in this array is defined in the constant HLI_POS_LOOKAHEAD_MAXIDX.

The array element position[HLI_POS_LOOKAHEAD_MAXIDX] contains the setpoint calculated in the current interpolator cycle. The element
position[HLI_POS_LOOKAHEAD_MAXIDX - 1] contains the setpoint of the previous cycle; position[0] contains the setpoint from before HLI_POS_LOOKAHEAD_MAXIDX cycles.

When the axis parameter P-AXIS-00256 is set, the delay between the interpolator and position controller is deactivated; in this case all array elements contain the setpoint calculated in the current interpolator cycle.

Signal flow

CNC → PLC

ST path

gpAx[axis_idx]^.ipo_state.position_lookahead_r.position[i]

Data type

ARRAY [0..HLI_POS_LOOKAHEAD_MAXIDX] OF DINT

Unit

0.1 µm

Access

PLC is reading

Special features

This data item is only available as of Version V3.00 and higher.

This cyclic look ahead must not be confused with the function “Estimation of future data“.