10.04.2013

An all-in-one solution

Vision systems are flooding the mechanical engineering market. All-in-one vision systems are conquering the world of automation technology and have long since become specialists suitable for series production.

Vision systems or VS are made up of image capture and image evaluation units.

Users can choose a camera and a PC or all-in-one vision systems based on ‘intelligent’ or ‘smart cameras’.

If a PC is already used as part of the automation solution, a camera can be connected to this PC using a standardised interface. A VS software library available on the market can then be added to the automation software to conduct the necessary image processing functions.

In addition to the option mentioned above, all-in-one visions systems offer many more features:

• The lens and lighting, the importance of which is often underestimated for successful image processing solutions, are already integrated into the device design

• Standard interfaces such as field buses can be used to simply and reliably integrate the systems into existing automation systems

• The often laborious integration into a VS software library is no longer required

• The vision system is separated from the actual automation software, reducing the complexity and thereby the level of implementation and maintenance work.

The challenge of modularity

In all-in-one designs, the individual components of a vision system are optimally integrated. In addition to the image capture and evaluation units, several LED lights and a broad range of lenses are also required.

With regard to the light, whether as a flexible device for individual tasks or a highly specialised sensor in series machine manufacturing, light colours of 470 (blue), 630 (red), 880 nm (infrared) and white can be implemented. The bright, homogeneous lights are directly connected and controlled by the vision system, making it easier for the user to both select and use the correct light.

When taking precise measurements of complex structures, telecentric lenses must generally be used to prevent perspective-induced measurement errors. This type of lens can also be used in all-in-one systems – this is where the advantages of the flexibility and expandability offered by such a system become clear. This modularity not only enables the vision system to be quickly configured, but also enables the basic device to be tailored to customer requirements.

 

Basic device with standard ring lights

Precision and communication – a requirement

An all-in-one system’s basic device has a robust housing, factory-based, pixel-level image sensor adjustment and a precise attachment system. All eight attachment bore holes (two on each side: M 4 to 10 deep) have 1 mm deep adjustment holes Ø6 H7 for attaching centring sleeves, which in turn have dimensions of Ø6 h7. During servicing, these centring sleeves ensure that the vision system can be quickly and simply replaced and also vastly reduce the realisation work involved with series production machines.

Reliable and intelligent networking of the vision solution with the central process control unit or the local PLC can be achieved through both digital 24-V process I/Os as well as field bus interfaces. In addition to the standard Ethernet, CANopen field buses also play a major role. The Sercos interface offers high dynamics in environments with drive systems. Robust connectors and a process interface integrated into the device allow for secure and simple connections in automation environments.

Usage example

Measuring only 63 mm x 63 mm x 69 mm, the system can be easily installed in the process environment. The industry-compatible IP 67 housing ensures reliable functioning even under difficult operating conditions.

The image data generated by high-resolution image sensors are inspected using efficient image processing algorithms.

The high-speed digital signal processor calculates the test results in real time; these are then exchanged with the system control unit via the on-board input/output signal. The software simulator for offline parameterisation proves to be particularly beneficial as certain ‘desk-based’ test processes can be created and tested without a connected vision system.

The ‘automatic test series’ function enables the test programmes to be quickly adapted for use with similar types of components. If desired and necessary, remote system maintenance can occur via either the integrated Ethernet interface or the available field buses.

 

In this version, the basic device has been configured in combination with an integrated lighting unit for a specific usage and is IP 67 compliant.

 

Vision&Control offers a comprehensive range of modules for the pictor® all-in-one vision system. Designed for use in industrial environments, the device concept can be combined as necessary with the manufacturer’s lenses and lights. The special modular design supports a wide range of user scenarios, enabling the system to handle a variety of industrial vision control requirements and tasks with extreme ease.

pictor® with spray guard: check to ensure seals are correctly installed