Case Studies

Stand Alone Continuous-Feed Packing Material Machine

Packaging
Posted in Consumer Goods, Embedded Development & Programming, Inventory and Warehouse Control, Manufacturing Automation and Intelligence, Product Development

Summary

DMC programmed the PLC software on a high volume, stand-alone machine used by the packaging industry to inflate and seal bubble wrap material.  To reduce cost, DMC also used extensive heat transfer testing and calculations to successfully implement an open loop control system.

System Modeling

System Modeling

System Performance

System Performance

Run Time Feedback

Run Time Feedback

Solution

DMC was asked to rewrite code for an existing, high volume machine that inflates and seals bubble wrap material to be used in packaging and shipping.  The customer's main concerns were improving operational reliability and improving the software architecture.  These were both important in order to reduce the frequency and difficulty in service required for machines in the field.

To accomplish this, DMC restructured the Panasonic FP-e PLC software to run on a State Machine architecture.  The code was also reworked and optimized using more advanced software functions to reduce the program size to 1/3 of the original program, allowing additional features to be added to the PLC's limited programming space.

Finally, to improve robustness of the heater, DMC used infrared temperature measurements of the system to calculate heat transfer properties of the machine.  Because the production machine was to run with no temperature feedback due to cost constraints, these measurements and calculations were essential to creating repeatable, robust performance.

DMC used the heat transfer calculations to implement a virtual model of the system in the PLC program, allowing control of the system to adjust to its usage and the conditions of its surroundings.

Thus, by restructuring the system architecture, improving the engineering calculations used for control, and optimizing software functions to reduce programming size, DMC was able to provide an updated system that was more robust and easier to maintain.

Customer Benefits

  • Engineering based calculations for control greatly improved robustness and repeatability over previous software
  • Worked virtually seamlessly with customer's existing software, hardware and training manuals
  • Organized and improved upon existing code, establishing standards and architecture
  • Improved code readability and debug for future in-field support
  • Compacted code size to as much as 1/3 of the previous version to fit more features into the same programming memory space

Technologies

  • Panasonic FP-e PLC
  • Resistive heating elements
  • DC Motor Control
  • Infrared temperature sensor