How to operate an electrical parallel gripper using CPRog and the Modular Control Electronics

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Application

The PG01 is a timing-controlled, electrical parallel gripper. It is mainly used in educational applications and not suitable for manufacturing.

The Gripper operates on +24V DC supply voltage and 24V signal voltage.

  • If the signal is high, the gripper motor will turn over for a set amount of time to open the jaws.
  • If the signal is low, the gripper motor will turn over for a set amount of time to close the jaws.

After the gripper has closed a small holding current thrugh the motor will ensure that the gripper grips the object.

Mechanical Integration

Robolink parallel gripper mount.png
  • The gripper is fixed with M4 screws to the flange of the robolink robot arm.
  • The cable to the gripper has to be routed, so that it does not catch or get stuck during operation.


Electrical connections

The gripper cable has to be routed via the cable ducts of the robolink robot and must be strain relieved.

The pink lead is connected to the positive 24V rail. The brown lead of the gripper is connected to the GND rail.
DIO module pinout.png
  • The pink lead is connected to the positive 24V rail.
  • The brown lead of the gripper is connected to the GND rail.
  • A connection has to be made between the 24V rail and the DIO module "Sup" pin.
  • The green "Signal 24V" lead of the gripper is connected to a DOut pin, e.g. pin 5. (If the green lead is connected to DOut pin 5 of the first (or only) DIO module, it can be addressed in software as DOut25. If the green lead is connected to DOut pin 1 of the first (or only) DIO module, it can be addressed in software as DOut21.)


Operate the gripper in CPRog

This could also be titled "how to switch a digital output in CPRog".

  • Turn on the power supply (or power supplies, when using a separate power supply for the gripper).
  • Disengage the Emergency Stop button
  • Start CPRog
  • Connect, Reset, Enable

Manual Use

This is e.g. useful for an initial test: The tab "DIN-Rail Input/Output" in CPRog allows to check the input states and to set the output channels for up to three DIO modules. Note that there is also a tab simply called (Input/Output) this tab is not relevant for the modular control electronics. When the physical robot is connected, only the outputs can be set. The inputs are shown based on the signals from the electronics. (During simulation, i.e. with the physical robot disconnected, also the input channels can be set to simulate e.g. sensors.) Only the outputs are relevant for the gripper that we are trying to operate.

To operate the gripper connected to pin D-Out B "5" of the first DIO module, toggle the tick-box before "25: Dout" as shown on the screenshot below.

DIO cprog 5th output manual.png

Use in CPRog Programs

The same can be achieved in a CPRog program. To operate the gripper set DOut25 to true/false as shown in the image below.

This enables the

  • fifth output of the first DIO module (DOut25)

DIO CPRog firstmodule 5th output.png

Once you save, load and run the program the gripper should operate.

The program in this video closes the gripper once. You can see the activation of DOut25 at the bottom of the video around 39 seconds into the video. If the program is run multiple times, the gripper will stay closed. If you want to open the gripper again, add another Digital Out command in the same way and set the state of DOut25 to false. The program here is just running the simulation. When the robot is connected, reset and enabled, it will operate the physical robot in the same way.

After opening the gripper it makes sense to insert a wait command, so give the gripper time to open prior to the next move.