21.01.2013

Plug and play

The vast majority of all production systems and machines have integrated image processing systems. Up to now, however, there has been a lack of fieldbus-compatible technology to allow end-to-end interoperability. With sercos-compatible industrial cameras, this gap can now be filled.

Industry experts are forecasting strong growth for the marriage of vision and motion. The requirements for high speed combined with simultaneous manufacturing precision are increasing continuously. However, these requirements can only be met through high performance – and end-to-end real-time networking – of all subcomponents.

Many plant and machinery manufacturers rely on the communication bus sercos to fulfil requirements such as a high data transfer rate, short cycle times combined with interference resistance, or the synchronisation of all devices in the ring with low jitter.

The communication protocol offers users and developers a wide and diverse selection of components for this, ranging from axes, axis systems, axis controllers, PLCs and drives to sensor systems and other peripherals.

Easier integration of image processing

Until recently, however, the problem facing industrial image processing users was the inability to integrate image processing in their systems directly, which made them unable to harness the benefits of the sercos bus system. The main disadvantages related to the integration work, which required a considerable amount of know-how. The lower transmission speed, lack of real-time operation and lack of synchronisation between the devices, which in turn caused jitter, were also problematic.

The pictor® and vicosys® image processing systems from Vision & Control have made these problems a thing of the past. Thanks to the on-board sercos interface, these systems can be rapidly integrated into the machine environment via the bus.

This provides the basis for time-synchronised, jitter-free triggering of an image processing system. The results of the image processing are also transmitted to the master via the bus, which ensures high processing speed and time synchronisation.

 

Solutions for a wide range of applications

The two new image processing systems feature high functionality that allows them to be used in many different industries and applications:

• Object localisation

• OCR

• Identification

• Colour analysis/colour classification

• Shape analysis/contour testing

• Completeness testing

• Metering

• Measurement

• Brightness analysis

• Surface analysis

Two different classes are available to users: pictor® intelligent cameras support all standard resolutions from VGA to five megapixels, in black and white or in colour. The cameras have an additional digital I/O interface in an IP67-compliant protective housing. All the image processing takes place autonomously inside the intelligent camera.

 

vicosys® multi-camera systems allow connection of up to eight cameras with different resolutions in colour, black and white or as line sensors.

The evaluation unit is an embedded PC suitable for industrial applications. The systems also have a digital I/O interface.

Individual combinations of device concepts with lenses and lights perform different image processing tasks efficiently and reliably.

Flexible parameterisation

The industrial image processing systems are parameterised using a Windows graphical user interface. The program is usually created by the machine manufacturer. Because parameterisation is carried out via the UCC (user control channel), the end user can also perform parameterisation without influencing the production process. Alongside the real-time data channel, the UCC is a separate channel for the configuration of components in the sercos ring. Configuration can be performed during operation without limiting real-time capability. It is also possible to initiate a change of program directly via the bus.

Operation of the whole system therefore remains consistent for the end user. It is also possible to teach the system to recognise new product types via the automation bus.

Up till now, image processing could not be integrated directly into a system with sercos, but only via indirect means.

The pictor® and vicosys® cameras now combine the advantages of image processing with those of the sercos automation bus. They therefore provide a simple solution for users.

The considerable amount of integration work, for which a great deal of know-how was needed, has been significantly reduced.

Future-oriented communication

Thanks to the addition of image processing capability to the sercos fieldbus, effective and fast communication can now be established between the motion controller and the image processing system. This allows visually initiated regulation of sequences of movements, which is increasingly in demand in quite a number of industries due to ever-increasing machine speeds.

 

Hot plugging, the insertion of components without stopping system operation, allows changes in the bus structure to be made at any time. The additional UCC also facilitates commissioning and configuration, even while the process is underway.