Innoventor Chooses PAC Platform for Industrial Automation

  Read in   |   Print Print

"With the PXI platform, we could easily synchronize industrial digital I/O, motion, and vision and use a single controller."

- Sam Hammond, Innoventor Solutions Inc.

The Challenge:
Integrating motion, vision, and industrial digital I/O for packaging automation in the beverage industry.

The Solution:
Using the NI PXI platform as a programmable automation controller (PAC) to easily integrate motion, vision, and industrial digital I/O with NI LabVIEW

Author(s):
Sam Hammond - Innoventor Solutions Inc.

NI Products Improve Manual Process

Innoventor Solutions Inc. is a producer of custom designs and hardware for plant modernization, process improvement, critical process control, testing and verification, and specialty equipment. We recently used the PXI platform as our PAC to create a packaging automation system for the beverage industry. Our customer previously installed labels on the beverage cans by hand and sorted them manually. This created a production bottleneck and increased the risk of motion injuries for employees. The per-piece average cycle time for the new system had to be 1.4 seconds. Since the labels on the cans have more than 150 possible color schemes and background patterns, an additional challenge was finding and reading the bar code on each can.

The complete automation system needed tight integration among three cameras, three stepper motors, and 50 industrial digital I/O sensors and actuators. Also, the control system had to be fast, reliable, and capable of implementing complex vision algorithms. We needed a PAC that had the functionality of a PC and, at the same time, the reliability of a programmable logic controller (PLC).

With the PXI platform, we could easily synchronize industrial digital I/O, motion, and vision and use a single controller. With LabVIEW, we could also use the same programming language for motion, vision, and industrial digital I/O. Having one controller for all operations, as well as a single programming language, reduced the overall cost of the system, making it less expensive than PLCs.

New System Uses Existing Equipment

We designed a custom system around a six-position rotary indexing table that we could place in an existing conveyor line. This system removes the cans from the in-feed conveyor and loads them onto the rotary indexer. After sequencing through the top-seal operation, the cans are placed on an outgoing conveyor that carries them to one of six wide packing conveyor tables. Multiple can label types can use the same top-seal type, thus keeping track of each can processed. Also, directing the can to the packing conveyor is necessary to eliminate manual sorting. The system uses a number of pneumatic actuators to pick the cans and operate a customized label applicator. We had to select pneumatics for their high speeds to meet overall cycle time. Each of the six stations in the system performs the following functions:

  • Station 1: A container is picked up from an in-feed conveyor and placed into a spindle base on the index table.
  • Station 2: Three cameras take pictures of the can and examine the images for the bar code. If the bar code can not be read, the can rotates for a better view of the barcode. Once the bar code is read, the station orients the can accordingly so the label can be applied.
  • Station 3: The seal is applied to the top of the can.
  • Station 4: The seal wings are pressed against the side of the can, and the seal is pressed tightly to the top of the can.
  • Station 5: This station is similar to the first station, except it removes cans from the rotary index table and loads them onto the out-feed conveyor.
  • Station 6: This is a normally empty position that is monitored for the presence of a container that remains due to an out-of-tolerance diameter.

Station 2 was difficult to implement and still achieve the desired performance. At this station, the location of the bar code first had to be detected around the perimeter of the can. The background artwork of the label made this difficult due to the variety of color variations, surface finishes, and patterns. A custom, three-level detection and discrimination scheme was developed for this purpose. This was further complicated by the distortion in the images off the center of the camera field of view (FOV) as a result of the camera distance-to-can diameter ratio. The presence of a bar code that was at the edge of the FOV could be identified, but the resolution and distortion prevented the reading of the bar code. In this case, the can was rotated to center the bar code in the nearest camera FOV. After reading the bar code, a second rotation of the can was required to orient the can for correct application of the top seal at the next station. Due to space constraints, the location and number of cameras did not allow for a full 360 degree viewing. If no bar code was detected in the first views by the cameras, the can was rotated to place the hidden parts of the cans in the view of the cameras. Worst-case positions of a can may require seven images and three moves to compete the operation at the station.

At Station 2, a large stepper motor drove the spindle through a friction drive wheel. Once the rotary index table was near the index point, the stepper was driven in on a pneumatic slide. At nearly the same time, a spindle break was released with another pneumatic mechanism. While all of this was going on at Station 2, the other operations at the other stations continued in parallel to achieve the part cycle time.

Improving Throughput and Accuracy

This top-seal applicator allows the customer to run the facility at 30 to 50 percent greater throughput with the same number of people used for the hand application of labels. These people now concentrate on the boxing of cans for shipment. The placement of the top seals is more consistent, preventing the label text from being obscured.

Author Information:
Sam Hammond
Innoventor Solutions Inc.
10 Kimler, Suite A
St. Louis, MO 63043
United States
Tel: (314) 692-9998
Fax: (314) 692-9942
shammond@innoventor.net

Bookmark and Share


Explore the NI Developer Community

Discover and collaborate on the latest example code and tutorials with a worldwide community of engineers and scientists.

‌Check‌ out‌ the‌ NI‌ Community


Who is National Instruments?

National Instruments provides a graphical system design platform for test, control, and embedded design applications that is transforming the way engineers and scientists design, prototype, and deploy systems.

‌Learn‌ more‌ about‌ NI