XGB EtherCAT Circular Interpolation

Circular interpolation is used to move two axes in a circular path based on the target position and type of circular interpolation mode.

The XPM_IST function block is used to execute the circular interpolation from the Position data table.
The axes being controlled must already be configured using the XG-PM software before using XPM_IST.
XPM_ECON and XPM_SVON must be executed before any circular interpolation moves.
This example is in scan program LP632_CircularInterpolation_Example in OnlineHelp_ECAT_Example.

XPM_IST Details

Element Name	Element Type	Description
REQ	Input	Edge detected request to execute the function block
BASE	Input	Base number of the motion controller. Set to 0.
SLOT	Input	Slot number of the motion controller. Set to the slot number of the XBF-PN04B or XBF-PN08B module.
AXIS	Input	Axis number of the main axis for the circular interpolation move. XBF-PN04B:1~4, XBF-PN08B:1~8
STEP	Input	Step to execute in the position table. Must be a value between 0 – 400. If value is set to 0, then the current step is executed. This can be a constant or variable.
DONE	Output	Status that function block is done.
STAT	Output	Current status of the function block. Non-zero numbers will be an error or warning.

Setting up the Position Table

The position table is setup in the XG-PM software.

Step	Action
1	Open the XG5000 project for the application. Go to Tools menuè Position Control to open XG-PM software.
2	Open the XG-PM project or Connect to PLC and select Project è Open from PLC.
3	Open the position data table in the Workspace for the axis that is being configured. This example shows Axis #1.

Step

Action

Open the XG5000 project for the application. Go to Tools menuè Position Control to open XG-PM software.

Open the XG-PM project or Connect to PLC and select Project è Open from PLC.

Open the position data table in the Workspace for the axis that is being configured. This example shows Axis #1.

Example of Moving in a complete circle

In this example Axis 1 is the main axis and Axis 2 is the sub axis.
The control types of Axis 1 and Axis 2 must match when using a relative circular interpolation move.
The target positions should be equal to 0 to move in a complete circle using relative circular interpolation.
The circular interpolation mode can be set to Center-Point, CW or Center-Point, CCW.
A valid circular interpolation auxiliary point (center point) must be entered.
In this example the starting points for Axis 1 and 2 are (0,0). The center point of the circle is chosen to be (1000,1000)
Step 15 in the Position table is being used for this example.

LP632