Omron PLCs help Cambridge University to explore the future of manufacturing

The Cambridge University Institute for Manufacturing (IfM) is using three CS1 programmable controllers (PLCs) supplied by Omron Electronics to provide the basis for a flexible, dependable and easy to configure automation system for the manufacturing automation lab which is the heart of the Institute’s work in the field of distributed automation and control.

The PLCs, which can be rapidly reprogrammed to match the evolving needs of the users of the automation lab, provide control over the transport systems that move products through the lab’s various zones, and for a turntable which supports the assembly cell’s tasks.

Following successful work on the use of RFID (radio frequency identification) tagging in packaging, warehousing and stock control applications, the IfM is currently concentrating on enhancing the complete manufacturing process. Its work includes addressing such issues as the life cycle of products and their components, the serviceability of products, ways of minimising end-of-life environmental impact, and overall cost of ownership.

In order to evaluate these complex issues, the IfM has set up the automation lab so that it can carry out all of the operations associated with the manufacture and packaging of a sample product. The initial product is a small gearbox of the type used in food mixers. The facilities in the lab will be used to produce these gearboxes using components that are RFID tagged.

This will make it possible to monitor the performance of the components individually revealing, for example, which of them are the most likely to fail, and which have useful life remaining when the gearbox as a whole is worn out.  This information is invaluable not only in suggesting areas for design improvements, but also for determining which components can be successfully recycled.

While the lab is currently being used to produce food mixer gearboxes, the ideas and concepts under development by the IfM are applicable to almost any manufactured product that is made up of multiple components. The value of the IfM's work has, for example, recently been convincingly demonstrated in relation to the production and maintenance of automobile engines.

So that it can offer facilities which closely resemble those of a typical manufacturing line, the IfM has configured its manufacturing automation lab so that it has three cells: machining, assembly and packaging.

Key features of the lab are the track systems that transport the gearboxes within and between cells, and a pick-and-place robot which is mounted next to a servomotor driven turntable so that it can easily be shared between the assembly and packaging cells.

In each of the cells within the lab, an Omron CS1 PLC is used to control the monorail track systems, including the gates and stops that ensure the products are routed to the appropriate destinations, and that they are positioned correctly when they arrive. To provide efficient control over the movement of products between the cells, the PLCs exchange information using Omron’s own easy-to-configure ControllerLink networking system.

The PLC in the assembly cell also controls the robot turntable, which uses an Omron servodrive system to ensure fast response and accurate positioning. The servodrive is linked to the PLC via a standard DeviceNet interface, which is also used to communicate with remote input/output modules mounted on the turntable.

The systems throughout the cell also make extensive use of Omron proximity sensors, particularly in connection with the end effectors used to pick up and move the gearbox components.

“For us, the Omron PLCs have two benefits which are extremely important,” said Andy Shaw, Business Manager for the Distributed Information and Automation Laboratory at the IfM. “They’re easy to program, and they offer a wide choice of programming methods. These features are essential not only because they allow us to modify our systems quickly to try out new ideas, but also because we use the PLCs as teaching tools.”

“The flexibility of the Omron products means that our students, who have a very limited time for project work, can quickly get to grips with them and start performing useful work,” he continued.

“In addition, they can choose whatever approach to programming suits them best, whether it is, for example, ladder diagram, statement list or even flowchart. Finally, whichever programming method they choose we know that they’ll be developing transferable skills, as the programming systems used by Omron are fully compliant with IEC 61131-3, the most widely used programming standard in the world of PLCs.”

Simon Sennitt, Mechatronics Technician for the laboratory, has been favourably impressed by the reliability of the Omron PLCs. “We certainly don’t give them an easy life,” he said, “but they consistently and reliably deliver what we ask of them. They’re worthy successors to the Omron C200 PLCs we’ve used in the past. In fact, even though our C200s are now quite old, even they are still so dependable that we keep a few in reserve for use on student projects.”

While the work carried out by the Cambridge University Institute for Manufacturing is, for the most part, driven by the needs and aspirations of its blue-chip industrial partners, the team at the Automation Laboratory is already looking at a number of ways in which Omron equipment can be used in the future to enhance the laboratory’s capabilities.

One proposal is the addition of Omron electronic operator interface panels. Easily networked with Omron PLCs, these offer a touch-screen display with text, graphical and video display capabilities, and would provide an ideal way to select various configurations for the systems in the cell. They would also make it possible to monitor the performance of the systems in real time, and to collect historical performance data for later analysis.

Another proposal is to use Omron vision products for automatic inspection of the components used in the cell, and also of the finished gearboxes and even the packaging. The vision systems could be linked with the electronic operator interface so that the results of the inspection processes could be viewed on the interface unit’s display screen.

Omron automation products are clearly providing Cambridge University Institute for Manufacturing with a convenient and effective solution to its automation needs. The last word must, however, go to Simon Sennitt. “The Omron PLCs do exactly what we want, they do it reliably, and they do it well,” he said. “Who could ask for more?”

'The pictures are provided courtesy of the Cambridge University, Institute for Manufacturing (IfM).'