The industrial ID system is one of the most flexible and essential parts of any processing or assembly operation that requires parts to move from one station to another. ID systems provide a chain of data that follows a part or assembly throughout the production process, and are a hand-off between one control system and the next. Innovations in ID technology have made the systems essential to familiar applications and a few unusual ones as well.

ID Makes Complex Processes Easy to Track

Wes-Tech Automation Systems in Buffalo Grove, IL, specializes in modular assembly systems for a vast variety of industries. By specializing in the assembly system components exclusively, Wes-Tech has been able to develop a range of standard modules that solve many of the most common assembly challenges. With this modular approach, Wes-Tech can design all-new lines, expand current systems, or develop simple single-station solutions.

On any assembly line, the most critical aspect is the control system. Accurately monitoring perhaps hundreds of operations, servos, tracks, and material stations is vital to any process. For Wes-Tech, not only do the hard components have to be flexible, but the control system must also be modular. This is where identification systems become critical, as they become the interface between one controller and the next and between the conveyor system and the product.

Wes-Tech uses Ident-I, System T from Pepperl+Fuchs, Inc, an inductive ID system that uses data carriers, or tags, to track each component as it travels down the assembly line. The Ident-I, System T allows the control system to identify each component as it rolls down the conveyor and to write new information to the tag indicating the state of the component.

Truck Manufacturer Uses ID To Enhance Productivity

Many vehicle builders have discovered that they can improve their assembly standards, retrofit a line with state-of-the-art technology, and add the ability to track their production process, all without any downtime on the line. One such company uses inductive identification technology to accurately track pallets of components through the robotic assembly processes and improve production efficiency.

This application uses a robotic arm to apply epoxy to vehicle components, which move to a second station where they are assembled in a jig. Initially, the system used traditional limit switches to position the pallets and trigger the epoxy application process. As the pallets passed the limit switches, the pallet count would be incremented, telling the controller that a pallet had arrived.

However, the pallets tended to shake as they moved on the conveyor system, occasionally failing to trigger the limit switches. At that point, the system would become confused, and the entire system would have to be restarted. It was a headache that plant supervisors and employees did not enjoy, but until the inductive ID system was installed, there was no simple, reliable, economical alternative.

Working with integrator Martin Control Systems, Inc out of Grove City, OH, plant engineers defined the problem: locate the pallets precisely, identify them (this tells the robot which components are on the pallet), and eliminate the problems that arise from the pallets rocking on the line.

Martin Controls modified the line's existing code to eliminate the limit switches and integrate the ID system into the facility's existing Allen-Bradley SLC 504. They installed inductive data carriers (known as "tags") on the front and back of each pallet, and 12 read heads were positioned along the conveyor. Each pallet is assigned a permanent number so the controller always knows which of the pallets is at each workstation. The tag on the front of the pallet identifies which components are on that particular pallet, while the tag on the back of the pallet tells the system when the pallet has exited the workstation and that it is clear to send the next one.

Using Allen Bradley Remote I/O in an ID application makes expansion easy because it does not require complicated wiring. If additional ID points are required, a new cable can be run to the additional read point. The system can accommodate up to 16 read points for each AB Remote I/O scanner. Very few additional ladder rungs are required for additional ID system locations, making future expansion economical.

Many ID retrofits can be completed without affecting production. In this case, the ID system could be installed alongside the existing mechanical limit switches, eliminating the need to stop or slow production for installation.