Tekna Automazione e Controllo’s innovative approach for fast and precise quality control of tires using 3D vision cameras

Quality control is essential for companies to ensure that the products they bring to market meet industry standards and produce the desired result. But it is often a demanding process, due in part to the increasing production rhythm and the complexity of identifying defects.

Intelligent quality control solutions automate this process and ensure a thorough and precise inspection – as demonstrated by the Italian specialist Tekna Automazione e Controllo utilizing  the Ruler3000 3D camera. As a result, they have produced a tailored solution for quality control in the production of tires.

Precise and Compact Solutions for Quality Control of Tires

One of the most important application areas for quality control is tire inspection in the automotive industry. It presents a particular challenge for machine vision for two primary reasons. First, the characteristics of the rubber itself (highly absorptive material), and second the different tire sizes and geometries and the tire sections (inner and outer) to be analyzed. These are tasks that need to be performed at high speed, high resolution, and with a high heterogeneity of defects.

The requirements can vary because of the resolution of the 3D camera and its size. For example, a tailor-made system is required when it comes to checking the lettering on the side wall of the tire or to detect possible defects on the inside of the tire. To meet this requirement, a compact camera must fit inside the tire.

The approach of Tekna Automazione e Controllo

This challenge is what the Italian company Tekna Automazione e Controllo set to solve. The company has been able to position itself over the years both in Italy and abroad as a system integrator for automation solutions for various industry sectors.

“We have continually expanded our market over the years. This gives our customers the certainty that our solutions are based on extensive experience,” said Michele De Stasio, Chairman of the Board of Directors at Tekna Automazione e Controllo.

The company started working in image processing several years ago. This includes tailored solutions involving the implementation of 3D laser triangulation systems with specially developed solutions and geometries. These are also used for tire defect inspections on their Vision Tire System 3D defects detection machines, which can identify defects on the inner and outer surface of the tire, for example scratches, bubbles, or deformations.

After consolidating its technology expertise, the company looked for a finished, but also reliable, solution for reading the lettering on the tire wall. This application is extremely difficult due to the color of the lettering (black on black) and its small size (1 mm x 1 mm x 0.4 mm high).

“Initially we couldn't find a suitable complete and integrated product that offers the same reliability as the solution we developed ourselves,” said Antonio De Stasio, Head of the Artificial Vision division at Tekna Automation and Control. “After the initial necessary testing, we established that a solution using the Ruler3000 3D vision camera from SICK works. The API provided helped us with integrating the system. Furthermore, SICK is especially valued as a partner by our customers.”

Precision and simplicity with Ruler3000

The company chose SICK, with whom it already had a longstanding partnership, and the Ruler3000 3D camera. The cameras can acquire high resolution images in the shortest possible time. This is achieved using the innovative 2560 x 832 pixel CMOS sensor from SICK with Rapid On Chip Calculation (ROCC) technology that allows a very high scanning speed.

Profiles at up to 7 kHz can be acquired over the entire sensor, or even up to 46 kHz with around 100 sensor lines. This enables the Ruler3000 to also record high resolution images in the direction of movement. These very high scanning speeds are also able to be achieved thanks to the high light sensitivity of the sensor, which allows a short exposure time even for highly absorptive materials such as tire rubber.

The Ruler3010 and Ruler3020 variants with medium-sized fields (maximum width of approx. 10 and 20 cm) are especially suitable for checking tire details. An example of this is the special case of the application developed by Tekna Automazione e Controllo for the Vision Tire System 3D labeling machine.

The application performs an inspection of the characters on the side of the tire to check their legibility, correctness and integrity based on the tire data sheets. As the system integrator, Tekna Automazione e Controllo integrated the Ruler3000 cameras in the automation structure of the machine. The cameras acquire high-resolution 3D images.

The company also developed a custom software for evaluating the correctness (or incorrectness) of the tire wall markings with the help of complex artificial intelligence and machine learning algorithms.

“We would never have been able to achieve this without precise and quickly available data, and we found an ideal partner for this in SICK who met exactly these requirements,” said Michele De Stasio.