Molding Operations - Tending Injection Molding Machines

Created by Rico Stodt, Modified on Tue, 8 Feb, 2022 at 8:37 AM by Rico Stodt

This page demonstrates an application regarding tending an injection molding machines and provides detailed information about the task development.


Application – Video




  • Re-register landmarks during initialize procedure.
  • Wait for input from part presents sensor on right or left conveyor.
    • If both are present, pick from the right conveyor first.
  • Pick part and move to a pneumatic cutter.
  • Trigger cutter to remove excess material from part.
  • Move part to final place location.
    • Final place location is two stacks of 40.
    • Contact place is used for the stacks.
  • While placing in the stack locations, command the pneumatic cutter to rotate and drop the scrap into a bin.
  • After both stacks are full, move to a wait location and wait for the operator to restart the sequence using a force push.

Gripper Information

Note: EOAT was designed and built by the end user with off the shelf parts from 3rd party suppliers and minimal machine work and build time.

Molding Operations 5.0 Gripper.png

  • Tool Center Point = (X)-63.5mm, (Y)0mm, (Z)114mm
  • Mass = 1769g
  • COM = (X)-30mm, (Y)0mm, (Z)50.8mm

Molding Operations 5.0 Gripper Settings 1.png Molding Operations 5.0 Gripper Settings 2.png

Task Overview

Molding Operations 5.0 Task Overview.png

Create and Set Up Signals and Variables



Four different signals are required for this application:

Signal Name



Left Conv Part



Right Conv Part



Gate Cut



Rotate Cut




All four signals are configured with the default value set to false. See the image below for an example of the configuration.

Molding Operations 5.0 Signal.png



Three different variables are used in this task:

Variable Name


Default Value

Empty Gate Cut



Pick Option



Place Count




The image below shows the final configuration of one of the variables.

Molding Operations 5.0 Variable.png

Key Task Elements

Task Work Flow

Molding Operations 5.0 Task Work Flow.png

Pick Sequence


  • A Wait Until node is used to prevent to robot from moving to a pick location until the left or right conveyor has a part available.
  • A Priority node and Do If nodes are used to force the robot to the right conveyor if both parts are available and also ensure the robot does not perform both pick sequences at once.

Molding Operations 5.0 Pick Options.png


Cut Sequence


  • Similar to the pick sequence, a Priority node is used to determine which of 2 sequences to follow.
    • The Pick Option variable controls which sequence will run.
    • Different sequences are required because the excess material is a different size depending on which machine produces the part.

Molding Operations 5.0 Cut Sequence.png

Place Sequence



  • Contact detection is used to place the parts in stacks with only one move to node.
  • The Place Count variable is used to determine if the parts should be placed in stack one or two based on current count.
    • Based on the condition shown in the Do If node, it can be seen that the parts are placed in stacks of 40.

Molding Operations 5.0 Place Sequence.png


Stacks Full Sequence


  • This sequence will only run if the Place Count has reach 80 meaning both stacks are full.
  • This sequence moves the arm to a safe position and waits for a force push by the operator to continue.
  • After the force push is received, the sequence resets the Place Count to 0 and begins moving back to home.

Molding Operations 5.0 Stacks Full.png


Empty Cut Sequence



  • This sequence runs in parallel to the robot sequence and is controlled by the Empty Gate Cut variable.
  • When the variable is set to 1 in the primary task, the sequence starts.
  • Output signals are used to command the pneumatic cutter to rotate, open, and rotate back.
  • The Empty Gate Cut variable is then reset.

Molding Operations 5.0 Empty Cut Sequence.png



Was this article helpful?

That’s Great!

Thank you for your feedback

Sorry! We couldn't be helpful

Thank you for your feedback

Let us know how can we improve this article!

Select at least one of the reasons
CAPTCHA verification is required.

Feedback sent

We appreciate your effort and will try to fix the article