Palletizers and depalletizers have evolved from basic, hand-operated machinery into highly complex devices that can be configured for virtually any layer pattern, product packaging or container — including cases, shrinkpacks, totes, bales and trays. The integration of a robotic arm into palletizers allows for floor space savings, product flexibility, and around-the-clock productivity.
Robotic arm integration is a natural extension of the the development of palletizers. Integrating PLC based control to the system allows for space
savings, product flexibility, and 24-hour productivity.
Intelligrated, Mason, Ohio, recently announced an evolution in robotic controls, the Alvey® PLC-controlled robotic palletizer. Using a common programmable logic controller (PLC) platform, Alvey is an alternative to the traditional proprietary robot controller and improves line integration, response time and overall productivity while reducing operator and maintenance training.
Earl Wohlrab, Manager of Robotic Integration at the company, tells Design World that line integration is simplified by allowing the robotic elements to be controlled with a common control platform.
“An example would be a robotic case packer coupled to a conventional case sealer coupled to a robotic palletizer,” said Wohlrab. “The current architecture for a system like this would require controllers for the robots, and these controllers have a different operating language than PLCs. Robotic controls therefore require an interface be set up so they can ‘talk’ with the PLC controlling the line operation. Once the robotic motion is controlled by a PLC, there is no need for the controllers or the interface, which often limits the amount of data that can be passed back and forth.”
The PLC-based control system enables customers to deploy new Alvey robotic palletizing systems while maintaining their standard control platform, streamlining complex control communication, and reducing changeover delays. This total PLC control provides a much higher degree of robotic integration and performance compared to systems requiring multiple control platforms. Currently, a palletizer would require multiple control platforms—there is generally a PLC for cell function and a controller for robot motion. With a PLC-controlled robot, the separate controller is eliminated and the PLC controls both cell and robotic function.
Using common hardware and programming tools, Alvey offers accessibility and convenience for robotic programming and maintenance. With minimal training, plant floor personnel can support these robotic applications without being robotic experts. Workers can program the palletizer through an intuitive touch-screen interface, while maintenance staff can service the palletizer with common spare parts already on hand—reducing inventory costs and downtime. Additionally, Intelligrated’s PLC control provides a convenient compact footprint by eliminating the need for additional control cabinets for each robotic application.
Wohlrab explained that PLC-based control is a natural progression for palletizers and related machinery.
“Other industries that have already accepted robotics into their automation development—such as the automotive industry—are less likely to embrace this right away. The reason … is that, while the material handling industry is based on PLC control, other industries (e.g. automotive) are based more on PC control,” Wohlrab said. “PLC-based robotics is something the material handling community has been asking for, and it makes a robotic application more accessible to facility personnel.”
Filed Under: Factory automation, Packaging, Mechanical, Motion control • motor controls, Mechatronics, PLCs + PACs