Rubber presents a challenge for optical-based measurement sensors. By nature, the black surface is difficult to capture reliable data from and accurately measure. This challenge is often intensified by the complex shapes into which rubber derivatives are extruded or molded.

As a solution to this challenge, 3D laser sensor manufacturers have optimised the design of their sensors to successfully implement scanning and quality control functions for both in-process and final product inspection applications in rubber and tyre manufacturing.

3D laser scanning

Rubber material comes in two forms on the production line, either as fresh and uncured from an extruder or a calender, or as a finished product (e.g., vulcanised tyres). Non-contact 3D laser scanning offers the most practical solution for inspection of both of these rubber material types.

Here’s why:

1. The soft, gummy nature of the rubber makes contact-type measurement ineffective. This measurement approach is also too slow to keep up with the high-speeds of continuous web material production.

2. 2D sensors require complex lighting to see black-on-black contrast. In some applications the lighting is placed underneath the material (e.g., when measuring the width of a strip), and hot sticking rubber can contaminate the lights. In addition, 2D can’t produce measurements related to object geometry (i.e., 3D shape), which means they are unable to measure critical features such as object flatness, surface angles, or part volumes, and are limited to contrast-based inspection. This makes 2D sensors a poor solution for scanning complex shape-based features on dark surfaces, or for operation in low lighting conditions.

          3. In comparison, 3D laser sensors are contrast invariants and generate high-resolution scans regardless of the material or lighting conditions. They also capture the complete 3D geometry of the scan target, including critical depth measurements on surface features such as grooves in a tyre tread. 3D laser sensors are also able to achieve the high speeds required for continuous web material scanning.

Laser profile sensors provide an ideal solution to both in-process and final rubber and tyre measurement and quality control applications. Built-in measurement tools for strip positions, including multiple groove location and depth measurement monitoring with automated alignment enable engineers to configure setup parameters––without requiring any measurement software development.

In addition, the ability to store multiple geometry configurations in the sensor makes changes between different recipes quick and simple, which is critical in minimising downtime for operations that make model changes multiple times per shift.

Application examples

1. In-Process Inspection

Extrusion Profiling with High-Resolution Gocator® 2440 Laser Profiler

Extruding rubber in a specific shape makes up the tread portion of a tyre. Measurement of the extrusion profile is carried out in-process, correcting the extrusion parameters in real-time to maintain the required shape. Key measurement parameters include thickness, width, and profile. Another required sensor capability is monitoring the position of surface features, such as ridges, center lines, and edges.

Profiling these tread extrusions is done by using 3D laser sensors to scan across the extrusion, generating a profile to which built-in measurement tools and pass/fail decision-making logic can be applied.

In this example, two Gocator 2440 laser line profilers are used to measure the rubber web’s extrusion groove pattern, geometry, and location with an X resolution down to 13 microns. Gocator 2440 sensors are able to inspect multiple grooves in a single setup, and groove measurements are unaffected by changes in surface angle relative to the sensor.

Most importantly, Gocator 2440 sensors generate critical 3D height data for robust shape measurement. 2D solutions are limited to contrast-based inspection.

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3. Final tyre inspection

Tyre Sidewall Inspection with High-Speed Gocator 2530 Laser Profiler

Traditional methods for measuring tyre sidewalls for defects such as bulges and dents suffer from too many false rejects (i.e., classifying a good tyre as defective). Due to measurement system limitations, many manufacturers have no choice but to “oversensitise” their sidewall bulge and dent measurement systems, resulting in costly manual inspection requirements for all rejected tyres.

In fact, some measurement systems cannot even distinguish between bulges or dents. However, with state-of-the art laser measurement precision and advanced built-in software analysis, false positive rates can be substantially reduced and, in many cases, eliminated altogether.

Using a Gocator 2530 laser profiler the engineer is able to generate full surface point cloud geometry data in order to detect small defects (down to 28 microns X resolution) anywhere on the sidewall surface. The sensor also delivers complete scan, measurement, and control at 4 kHz, allowing engineers to meet stringent cycle time requirements––with no need for industrial PCs or external controllers.

In this configuration, two profile sensors are typically used, one for each sidewall (top and bottom buddy system). A third sensor is often used to monitor radial runout of the tread.

Leveraging 3D Laser Scanning and Inspection

Laser-based laser triangulation sensors meet the high speed and high resolution requirements for accurate rubber and tyre measurement. These sensors are used in a variety of in-process and final inspection applications, including extrusion profiling and tyre sidewall inspection.

Adding 3D laser sensors for automated quality control is vital to reducing scrap and rework, and improving final product quality by maintaining consistency throughout the tyre manufacturing process.

Courtesy of LMI Technologies www.lmi3d.com

Hana Technologies, Inc. (Hana RFID), a global leader in the design and manufacturing of embeddable RFID tyre tags, has become the first RFID company to join the Circular Rubber Platform. This development aligns with Hana RFID’s mission to drive innovation in tyre traceability and reinforces the company’s long-standing commitment to sustainability and circularity in the tyre and rubber industry.

Hana RFID has been at the forefront of RFID-enabled tyre traceability since 2005, facilitating smooth tracking from cradle to grave and promoting circularity. Hana's RFID tyre tags, which are embedded during manufacturing, provide each tyre a distinct digital identity, facilitating complete lifetime tracking from manufacture and use to recycling and reuse. Hana hopes to promote RFID usage in sustainable tyre lifecycle management by working with leading companies in the sector, which will eventually save waste and increase resource efficiency.

Using radio frequency identification (RFID) technology, an RFID tyre tag is a tiny, embedded device that tracks, monitors and controls tyres. In addition to providing smooth connection with inventory monitoring, fleet management systems and other digital applications, such as the European Digital Product Passport (DPP), these tags produce digital twins of tyres. Hana's RFID solutions empower the whole tyre ecosystem to expedite fleet management, improve inventory control, optimize maintenance, and create creative business models that increase sustainability and efficiency.

Val Peters, VP – Marketing, Hana RFID, said, “We are excited to join the Circular Rubber Platform as the first RFID company in this initiative. RFID technology is essential for advancing a circular economy in tyre manufacturing, and we look forward to collaborating with partners across the rubber sector to drive sustainability on a broader scale.”

Enrico Koggel, Co-Founder, Circular Rubber Platform, said, “RFID technology is key to enabling a circular rubber economy. RFID enables seamless tracking from production to end-of-life recycling by connecting material and production data into each rubber product. It provides traceability and easy identification and allows for smart sorting of materials and efficient recycling to ensure responsible reuse, remanufacturing, recycling and waste reduction. We are therefore very happy to announce Hana as a new member of the Circular Rubber Platform, with the technology and experience they can provide to the platform. We look forward to sharing knowledge on RFID and working out opportunities for this technology in rubber industries that require Digital Product Passports in the near future, such as footwear.”

TÜV SÜD has expanded its test laboratory in Frankfurt am Main and unveiled new testing facilities at an Open Lab Day at the site, giving customers and employees an exclusive insight into the new state-of-the-art testing environments. The expansion strengthens TÜV SÜD’s position as a leading provider of independent testing and certification services.

Car charging plugs can now be tested in the lab to assess features like weather resistance, mechanical strength and electrical safety. To guarantee the endurance and durability of charging plugs and other parts, the new lab can also conduct crash testing on them. The inclusion of performance testing for tiny batteries is another significant development. Basic functional analysis will be the main emphasis of these tests at first, but in the second part of the year, comprehensive safety and performance evaluations will be included. Similar to this, power tool testing capabilities have been greatly increased to give manufacturers an even more thorough evaluation of the calibre, robustness and safety of their goods.

The capability to ascertain the biogenic carbon content of materials is an additional highlight of the expansion. These assessments support the implementation of sustainable manufacturing methods by giving businesses evidence of the utilisation of renewable raw resources. In order to make sure that packaging and other materials fulfil the strictest safety regulations and don't leak dangerous compounds into food, the testing infrastructure for materials that come into contact with food has been increased at the same time. It's also important to note the recently added ability to evaluate welding fume filtration systems, which may undergo a thorough performance assessment and will soon be certified.

TÜV SÜD is now able to provide an even greater variety of chemical testing services to make sure that products satisfy the most recent regulatory standards thanks to the expansion of its Frankfurt laboratory. With standardised testing for compounds including PFOS, PFOA, C9-C14 PFCAs, and PFHxS, there is a special emphasis on PFAS analysis. Due to the laboratory's expansion, even more businesses may now make use of its extensive testing knowledge, which includes services related to durability testing, risk assessment and certification for a range of product categories.

Walter Reithmaier, CEO, TÜV SÜD Product Service GmbH, said, “By expanding our laboratory in Frankfurt, we are responding to growing demand for product testing and certification. Our new testing capacities will set new standards in safety, sustainability and performance. We look forward to supporting our customers with state-of-the-art testing technology and professional expertise.”

Chicago-based Koala Technologies (KTL), a leading automotive testing, measurement and evaluation tools provider, has launched Te.Sense Bloom – a breakthrough in non-destructive rapid tyre deflation testing. The company has introduced the base kits starting at USD 20,000.

The solution the company claims is fully compliant with FMVSS 110 and emerging EV stability test standards. The Te.Sense Bloom allows passenger vehicle manufacturers and tyre makers to cost-effectively reuse solutions, thereby optimising test programmes while reducing waste.

Currently, the rapid tyre deflation tests often rely on a vehicle being driven over special roadway cleats at defined speeds. This method sees tyres destructively punctured and destroyed by the cleats, and internal inflation pressure is quickly reduced to atmospheric pressure. At times, these tests aim to ensure that the tyres are safely seated on the wheels post rapid deflation, wile at times it is to evaluate vehicle stability in terms of tyre failure.

The company stated that this tests however require destroying multiple tyres, not only leading to waste but may also corrupt certain vehicle dynamics tests that call for a single, targeted tyre failure.

On the other hand, with Te.Sense Bloom, the industry can use non-destructive controlled, rapid deflation for the selected tyres. Using a controllable central air ejector valve with a volume and a flow capacity that simulates a sudden tyre press loss. While the method sounds simple and frugal, the innovation lies in relation with the turn-key nature of Te.Sense Bloom. Automotive testers and engineers get a repeatable set up method, easy in-car operation and simple connectivity with data acquisition systems. As part of its comprehensive supply to Te.Sense Bloom customers, KTL even offers a wheel setup service to simplify test preparations.

The other advantage of Te.Sense Bloom is that the tyre deflation event can be triggered from inside the vehicle or remotely that further expands test scenario possibilities. It can be used for testing tyre inflation pressures up to 100 PSI and speeds up to 140 kmph (87 mph). The real-time tyre inflation data at 100 Hz has a claimed data accuracy of +/-0.1 PSI.  

Kenneth Martin, Head of Tyre Testing at the Transportation Research Center, said, “We have significant experience with rapid tyre deflation tests, using all types of methods, and we’re looking forward to evaluating KTL’s Te.Sense Bloom, since it represents a turn-key, non-destructive solution. There’s definitely some baseline justification for test equipment like this because it fundamentally means consuming fewer tyres. But Te.Sense Bloom’s inherent connectivity opens some other doors also, since triggered and monitored rapid tyre deflations are becoming an area of interest for vehicle stability testing, especially in EV space.” 

The first U.S.-specification kit has been delivered to the Transportation Research Center in Ohio for initial evaluations.

Being compliant with EV stability testing standards the Te.Sense Bloom is already being used by OEMs globally such as Huawei AITO, SAIC Motor Corp and GAC Motor to conduct regulatory tests such as GB/T 38796-2020 (Performance Requirements and Test Methods of Automobile Blow-out Emergency Safety Device).

Mike Lee, Founder and President, KTL, added, “Koala Technologies is excited to introduce Te.Sense Bloom into new markets, beginning in 2025. Bloom has been widely adopted for vehicle development testing in China over the last several years, becoming a must-have tool for many OEMs and key suppliers. It’s one example, among many, of an excellent, trusted, useful automotive testing device that no one knows about outside China. A part of our mission at KTL is to shine a light on some of these exciting technologies that are currently available, but not widely known. Another part of our mission is to help customers achieve their goals more efficiently and at a lower cost. We look forward to the upcoming testing at the Transportation Research Center in Ohio, and we hope that Te.Sense Bloom proves to be a good fit for automotive development programmes in the U.S and beyond.”

Bridgestone Corporation has developed a new Tyre and Road Wear Particles (TRWP) vehicle collection method aimed at understanding the environmental impact of TRWP. The solution was also displayed at the Tire Technology Expo 2025, held in Hannover, Germany, from 4 to 6 March.

TRWP is made up of a blend of road pavement components and tread (tyre surface). In order to comprehend the particle size distribution, dispersion behaviour, and environmental impact – as well as to create effective collecting techniques – Bridgestone is actively engaged in a number of TRWP research projects. The company is dedicated to comprehending TRWP and lowering its generation through these initiatives.

Utilising the B-Mobility testing facility at the Bridgestone Innovation Park in Kodaira, Tokyo, the company has created a state-of-the-art technique that makes it possible to gather TRWP effectively. Bridgestone has used laser light scattering in conjunction with a high-speed camera to visualise the dispersion of particles like TRWP. Based on this, the company has developed a device that effectively catches TRWP and covers the whole tyre. Additionally, the technique made it possible to collect TRWP effectively in a state that removes the effects of exhaust pollutants and broken dust by employing autonomous driving and an electric car with regenerative braking.

Through the Tire Industry Project (TIP), which is part of the World Business Council for Sustainable Development (WBCSD), Bridgestone has been researching the physical and chemical properties of TRWP and their implications on the environment. In addition to the continuous co-creation and internal R&D cooperation, Bridgestone is speeding up its efforts to evaluate TRWP's environmental consequences by collecting it effectively and with a high recovery rate using its recently developed collection technology.