Machine vision is playing an increasingly important role in modern manufacturing. Self-optimizing production processes, for example, rely on real-time feedback from imaging-based inspection. So far, however, even the most advanced machine vision systems have been impaired by inadequate integration into the control system at large. B&R's new fully integrated solution is now set to unleash the full potential of machine vision.
"Seeing is believing," the old adage tells us. Indeed, vision is the most trusted of the human senses – and the one we use most to interact with the world. "In contrast," says Andreas Waldl, product manager for integrated machine vision at B&R, "many of today's machines are more or less flying blind."
For years, OEMs have been trying to resolve this shortcoming by means of machine vision. As companies work toward implementation of Industry 4.0, such vision systems can be a valuable tool. "At the moment, however, machine control and machine vision still live in two different worlds," says Waldl. Incorporating a machine vision system into an application remains an extremely complex task.
"We have developed an embedded vision system whose flexibility and unprecedented level of integration eliminate the drawbacks previously associated with these systems," says Waldl. At the heart of the solution is a broad selection of intelligent camera technology. Options at the lower end will replace simple machine vision sensors, while the top of the range will harness the full potential of high-end smart cameras. These cameras are capable of performing a wide range of machine vision tasks that are currently still being carried out by PC-based systems.
A key component of B&R's machine vision system is intelligent lighting technology. Lighting elements are available integrated in the camera, as an external device, or even as a combination of the two. Automatic lighting modulation prevents stray light and other difficult lightingconditions from compromising performance. It also makes it easy to achieve extremely precise synchronization for high-speed image capture or implement object-specific requirements such as bright-field or dark-field illumination.
"B&R's machine vision system is integrated on every level: the engineering tool, the real-time operating system and the application software," emphasizes Waldl. The holistic approach encompasses every aspect of an automation solution: from the control system to the safety technology and from motion control to robotics and CNC. "And now that includes machine vision as well."
With cameras and lighting just as integral as I/O modules, servo drives and safety controllers, there's no longer a need for interfaces in the runtime system. Tasks like programming and configuring image processing routines, as well as the settings for the camera and lighting, all become part and parcel of the overall automation project.
Control programmers are able to carry out numerous machine vision tasks themselves. All data, parameters and variables are standardized throughout the entire system – no separate process variables are required for machine vision. The only time vision specialists will need to be consulted is in situations that require their specific expertise, for example in handling difficult lighting conditions.
B&R's mapp Technology framework provides ready-made software components that make it easy to create machine vision applications with minimal programming. Since mapp components communicate intuitively with one another, all it takes is a few clicks to do things like integrate images captured by a smart camera into a mapp View HMI application. And all without writing a single line of code. The camera and lighting parameters as well as trigger conditions can all be changed on the fly, making product changeovers and other runtime adjustments very easy to implement.
Potential applications for B&R's machine vision system range from relatively simple tasks – like reading barcodes, OCV and OCR – to the most demanding tasks found in pharmaceuticals, printing and textiles.
The different camera models can be scaled seamlessly and are all based on the same technology. This allows OEMs to equip different machine variants with different configurations of the machine vision system. The software only needs to be created once, regardless of which hardware configuration is installed. Since the application is also stored on the controller, no data is lost if the camera is replaced during servicing.
Cameras and lighting are directly integrated into the real-time network via POWERLINK, which not only ensures tight synchronization with machine and motion control, but handles HMI communication as well.
Rather than following the circuitous route they’ve been forced totake in the past, trigger signals come directly from the controlor motion application. The ability to synchronize image triggers and lighting control with the overall automation system – in hard real time and with sub-microsecond precision – opens up a new world of opportunities. In dynamic applications with frequently changing speeds, for instance, you no longer need a separate encoder on the camera input.
By fully assimilating machine vision into its automation system, B&R now allows machine builders to implement both control and machine vision tasks with a single tool. As Waldl summarizes: "Rather than struggling with the inadequacies of traditional vision systems, they can refocus that energy into optimizing their machine's value-adding processes."