Q+A CENTER

Against the backdrop of tireless discussions about the “right” data transfer interface in industrial image processing, one aspect is unfairly pushed into the background – mainly the criteria of the users with regard to its usability in a hard industrial environment.

The values theoretically possible when it comes to all kinds of digital transmission standards for cameras quickly pale when they’re applied to systems in a rough environment with special requirements. Therefore, choosing the “right” camera for the inspection tasks at hand, includes taking a look at other important criteria. These are criteria that a standard also has to meet, besides the simple transfer speed of data. So the decision on a transmission standard involves answering some questions that determine its direct usability:

• Will the cable length provided by the standard suffice for my application?
• Are there cables designed for heavy use (keyword: ground tackles)?
• Can the cables be used for industrial purposes in all matters (keywords: industrial plugs, lockable)?
• Are technically compatible accessories, such as hubs and repeaters available on the market?
• Can PCs and laptops be equipped with corresponding cards?
• Are drivers and viewers available that are right for the software (keywords: interfaces for WDM, TWAIN, etc.)?
• Are the specific cameras and their interfaces supported by the established image libraries?
• Is the chosen interface sufficiently compatible with standard PCs and the operating software in use (keywords: Windows, Linux) and is it appropriately supported by the manufacturers?
• Will I have to invest in additional accessories (e.g. frame grabber) that push up costs, possibly driving up TCO as compared to other standards?
• Which functions are already pre-processed internally by a camera of a certain standard, saving resources in the subsequent image processing by PCs?

One reason why Allied Vision Technologies concentrates so much on the development of cameras with Firewire technology is without a doubt the industrialization capacity of this interface, which is very well developed. The continued development of the IEEE1394 standard already makes possible 800Mbit/s at this point. The next step, 1600Mbit/s and 3.2 Gbit/s, is already on the road map for Firewire. Here’s why this standard is a safe investment: with each continued development, the compatibility with the preceding standard is taken into account and vice versa. In other words, IEEE1394b is backward compatible with IEEE1394a, preventing investments already made from suddenly becoming worthless due to new standards or preventing standards from being outpaced one day by continued technical development.

The following examples illustrate the multitude of accessories, greatly increased by now, with industrialization capacity that offers solutions for complex image inspection tasks.

IEEE1394 Cable

Getting started in the 800Mbit/s IEEE1394b standard takes extremely flexible cables. A new small connector (available in two versions) paves the way for large bandwidths. Up to 2GHz is possible using regular copper cables that have convenient industrial interlocking so that components can find their place in every AVT camera and so they perfectly understand IEEE1394 standard repeaters and computer cards.