Semi-Automation of an Optical Component Manufacturing Process

Challenge

Our client needed to introduce automation to a highly manual manufacturing process for injection molding of precision components. The manual process was slow, and yields were low, causing excessive waste. The low yield was traced to the inability to control the critical process variables.

Solution

Viewpoint decided to integrate a PLC, a motion controller, and LabVIEW to develop a solution for a “first phase” automation system to replace the highly manual process.

The PLC:

1. controls eight axes of motion,
2. controls the UV light for curing,
3. and interfaces to other process equipment such as valves and sensors .

The LabVIEW application:

1. guides the operator through the manufacturing process step by step,
2. interacts with the PLC,
3. and displays real-time process data and log data to a file for further review post manufacturing.

Benefits

Besides the automation benefits of consistency and speed, the client wanted the ability to adjust configuration settings and limits for almost every aspect of the operation, such as setpoints and motion stage positions. Configuration screens were developed that let an operator run through the manufacturing steps manually while making adjustments on-the-fly; perfect for “dry-run” production simulations. These screens require special permissions to operate in engineering mode rather than production mode.

The other benefits are:

• Reduction of set-up cycle time increasing component throughput.
• Reduction of variability of the manufacturing process.
• Increased product yield resulting in reduced waste.
• Reduced probability of product contamination due to automation and cycle time reduction.
• Data files enable review of past manufacturing data and potential process improvements.
• Part traceability enables better process understanding and control.
• Prompts and machine status checks help guide novice operators.
• System is configurable for different product lines.

System Overview

The entire system consists of the following components:

• A PLC controlling the motors responsible for positioning the tooling and other process equipment.
• A standalone controller responsible for controlling the process temperature.
• A LabVIEW application to serve as the operator’s interface to the manufacturing process. The application is responsible for tasks including:
  • Guide the operator through the process.
  • Provide important information about the process to the operator.
  • Display any warnings/alarms detected by the PLC.
  • Write process data to a file.