Precise measurement of water-cut objects
Case History WatAJet
The customer was asked to develop a unique setup both inline and offline for: dimensional control of the products onboard with a user interface, positioning of the cuttings online, automatic dimensional control of the pieces offline.
A high measurement accuracy, less than 0,1 mm, was required. Moreover, there were strict space constraints inside the machine, thus a compact solution was needed.
For customers dealing with precise measurement applications in harsh environments, TCCX series is an ideal solution thanks to the long working distance, excellent optical performances and integrated coaxial light. Moreover, FabImage® software provides simple yet powerful image processing tools to get the best out of your vision system.
The choice of the optics
As aforementioned, some important aspects had to be considered:
- Tight space constraints of 100 mm x 150 mm x 100 mm on X, Y, Z
- Harsh environment
- Field of view of 14 mm x 14 mm
Given that a 2/3” sensor is required to achieve the desired accuracy, a lens with magnification lower than 0,506X is needed.
Both the TCLWD and TCCX series by Opto Engineering® are suitable to satisfy all the requirements: they both have long working distance and meet the space constraints. The difference between the two is in that TCCX series features an integrated coaxial illumination, while TCLWD does not. The discriminant for the choice, thus, was the best type of illumination for the application.
The choice of the illumination
Most of the times, the ideal illumination for measurement applications is a backlight, possibly collimated. In this case this wasn’t an option due to the water jet and the abrasive material. As discussed in the previous section, after choosing the optics two different types of light were considered: coaxial (integrated in the lens) and ring light. Generally, if the sample is not perfectly flat a ring light leads to better illumination, while with flat objects a coaxial light lead is preferred because of the stronger edge transition. In our case, the objects are typically flat, hence the coaxial light solution was chosen.
The choice of the software
Once the hardware was chosen, the missing piece in the design of a complete vision system was the software. The choice fell on FabImage®, a data-flow based software by Opto Engineering® designed for machine vision engineers. Thanks to FabImage®, in fact, it is possible to develop a Human-Machine Interface easy to use onboard that even non-expert users can utilize due to its graphical programming environment.
WatAJet
Why Opto Engineering®?
Being the first approach to machine vision for the customer, Opto Engineering® was able to guide the WatAJet team in choosing the right vision components to meet the strict requirements of the application. Furthermore, the quality of the products, the support during the design phase and the possibility to test the system before buying it, convinced the customer to finalize and realize their idea. Advanced technological solutions sometimes require overcoming obstacles along the way, and this is only possible if you are relentless in the pursuit of the goal. Having an experienced partner that can help you at every step of the way definitely makes things a lot easier, as in this case.