Controlling a Cam Drive with a Virtual Time Axis

Refer to the sample project PLCopenMulti.project in the installation directory of CODESYS.

This example demonstrates how to implement a periodic cam on a linear drive. The example also demonstrates how to use the tappet function.

Insert a cam named Example in the device tree below Application. Open the cam in the editor.
Define a tappet in the Tappet tab.
- X: 8.0
- Positive pass: Invert
- Negative pass: Invert
Insert a virtual drive named Drive in the device tree below SoftMotion General Axis Pool. For this axis, select the axis type Modulo with a modulo value of 360.
Insert another virtual drive named Virtual. For this axis, select the axis type Modulo with a modulo value of 10.
Create a MOTION_PRG program in CFC.

PROGRAM MOTION_PRG
VAR
       power1, power2: MC_Power;
       TableSelect: MC_CamTableSelect;
       CamIn: MC_CamIn;
       Tappet: SMC_GetTappetValue;
       MoveVirtual: MC_MoveVelocity;
END_VAR
Insert a function block and assign the variable power1 to it. The function block is used for switching on the Drive.
Configure the inputs as follows:
- Axis: Drive
- Enable: TRUE
- bRegulatorOn: TRUE
- bDriveStart TRUE
Insert a function block and assign the variable power2 to it. The function block is used for switching on the Virtual.
Configure the inputs as follows:
- Axis: Virtual
- Enable: TRUE
- bRegulatorOn: TRUE
- bDriveStart TRUE
Insert a function block and assign the variable MoveVirtual to it. The function block is used for moving the virtual master.
Configure the inputs as follows:
- Axis: Virtual
- Execute: power2.Status
- Velocity: 2
- Acceleration 10
- Deceleration 10
- Direction positive
Insert a function block and assign the variable TableSelect to it. The function block is used for selecting a cam.
Configure the inputs as follows:
- Master: Virtual
- Slave: Drive
- CamTable: Example
- Execute TRUE
- Periodic TRUE
- MasterAbsolute TRUE
- SlaveAbsolute TRUE
Insert a function block and assign the variable CamIn to it. The function block implements the selected cam plate.
Configure the inputs as follows:
- Master: Virtual
- Slave: Drive
- Execute power1.Status
- MasterOffset: 0
- SlaveOffset: 0
- MasterScaling: 1
- SlaveScaling: 1
- StartMode: absolute
- CamTableID: TableSelect.CamTableID
- VelocityDiff: 1
- Acceleration: 1
- Deceleration: 1
- TappetHysteresis: 1
Insert a function block and assign the variable Tappet to it. The function block checks the setting of the cam switch.
Configure the inputs as follows:
- Tappets: CamIn.Tappets
- iID: 1
- bInitValue FALSE
- bSetInitValueAtReset: FALSE
⇒ The tappet is defined as an inverting tappet. For this reason, its value is changed every 10 seconds.
The sample project provides a visualization for checking the individual function blocks and the position of the axes.
Add the call of the MOTION_PRG program to the task MainTask.
Load the project to the controller and start it.