LASIT’s laser expertise and LMI’s 3D sensors revolutionize Easy Check

The Easy Check application on brake discs

The Easy Check system has become the industry standard for disc wear monitoring, based on engraving one or more logos directly on the braking surface. These indicators, also known as “wear indicators,” allow immediate and intuitive visual inspection of the disk’s condition. LASIT has not merely replicated this process, but has developed a solution that elevates its accuracy and reliability by integrating advanced technologies to meet the high productivity needs of the automotive industry.

The technical challenge

Traditional inspection methodologies, which rely on manual measurements or mechanical systems, have significant limitations in terms of accuracy and repeatability. The complexity of the marking process lies in the need to make precision engravings with extremely strict tolerances of 100µm ±5µm. It is crucial that each Easy Check marking has the correct depth: too shallow a marking would be ineffective, while too deep a marking could compromise the structural integrity of the record.

Brake disc manufacturers face complex challenges, which include choosing the right laser technology and impeccable quality control.

Stringent requirements for laser marking

The Easy Check marking process requires a high quality that only advanced laser technologies can guarantee. LASIT has chosen to use picosecond lasers, a technology superior to commonly used nanosecond lasers, for a “cold ablation” process that prevents thermal alteration of the material. This method ensures an optimal surface finish, sharp edges and a uniform background without remelting, ensuring maximum mechanical reliability of the disc and preventing micro-cracking. LASIT relies on industry-leading partners such as IPG, offering picosecond laser solutions with powers of 50W, 100W, and 200W, depending on application specifications.

High standards for quality control The shiny, metallic surface of brake discs presents a significant challenge to conventional vision systems. Inspection for compliance of Easy Check markings requires high-precision measurement systems that are also fast, so as not to slow down production cycles.

The LASIT ROTOPIC Solution

To overcome these challenges, LASIT developed the ROTOPICO system, an integrated solution that combines picosecond laser engraving with automated quality control using LMI Technologies’ Gocator® 2510 sensors. The system is based on a machine with XYZ motorized axes, equipped with a solid steel structure that eliminates structural vibration, ensuring maximum precision during engraving and measurement. The ROTOPICO system architecture, with an integrated Gocator® 2510 profilometer control, allows the depth of each incision to be verified with micrometric accuracy.

The process is carried out in several stages:

1. Load: The disk to be marked is placed on the rotary table.
2. Laser marking: The disk is marked at three points, typically 120° apart. The machine’s rotating axis rotates the disc 120° for each marking, keeping the laser beam always perpendicular to the surface and ensuring maximum accuracy.
3. Table rotation: The rotary table moves the disk to the quality control station.
4. 3D Profilometry: The Gocator® 2510 sensor, mounted on a linear axis, scans and reconstructs the surface of the Easy Check marking.
5. Analysis and validation: The software analyzes the depth of the engraving, verifying that it is within the range of 100µm ±5µm. The part is accepted or rejected based on compliance with the specifications.

Benefits of the partnership between LASIT and LMI

The synergy between LASIT’s engineering expertise and LMI Technologies’ advanced technology has created a solution that offers the best of both worlds. The integration of the Gocator® 2510 sensor into the ROTOPICO system was a key element in the success of the application. The benefits of this component are many:

• Accuracy and reliability: The sensor offers sub-micrometer resolution and laser triangulation technology that makes it immune to variations in surface color and reflectivity, critical aspects in the processing of brake discs.
• Speed and productivity: With scanning capability up to 20 kHz and data processing directly on board the sensor, the Gocator® 2510 enables inspection in masked time without slowing down production, a key requirement in the automotive industry.
• Integration and robustness: The compact design and IP67 protection enable its easy integration and reliable operation even in harsh industrial environments, eliminating the need for complex calibration procedures.

Through this partnership, LASIT can offer its customers a comprehensive system that ensures:

• The assurance that each Easy Check indicator meets the rigorous depth specifications.
• The drastic reduction of noncompliant parts.
• Full traceability of each control, a prerequisite for compliance with industry regulations.