Stoneridge is a global designer and manufacturer of highly engineered electrical components and systems for commercial vehicles, automotive, off-highway and agricultural vehicle markets. These parts are the core of mechanical and electrical systems and improve overall vehicle performance in areas such as emissions control, fuel efficiency, safety and security.

Founded in 1965, Stoneridge has a vast amount of experience in this field and will have a vital role to play in the future of automotive manufacture. With the developing trend of autonomous vehicles, and the constantly increasing emphasis on the environmental aspect of vehicles, the activities at Stoneridge now and in the future are of growing importance. Stoneridge manufactures application-specific switches and actuators, sensors, security alarms, vehicle tracking devices and monitoring services which are subject to extensive testing and quality control. These items are critical to the safety of road-users and vehicle security. Especially with autonomous driving on the horizon, component failure is not an option.

Extensive environment simulation testingTimo Jakimainen is the Senior Engineer in the test laboratory at the Stoneridge factory based in Tallinn, Estonia. He is the primary CMM operator in the laboratory and has been sharing his knowledge by training his colleagues in use on the latest installation. Timo

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Stoneridge in Tallinn, Estonia, recently installed the Nikon ALTERA CMM with LC15Dx laser scanner in its test laboratory to take inspection of automotive components to the next level. The Laser scanner provides many advantages including complete visualisation of parts, non-contact measurement for delicate components and repeatable measurements.

Automotive supplier identifies mystery error using Nikon laser scanner

introduces the test laboratory with a tour, demonstrating the broad range of equipment which is used to assure absolute top quality of components for all clients. In manufacturing automotive components, there is a growing emphasis on the quality of components. They are expected to have a longer life cycle and need to meet tougher demands. Therefore, before mass production, all components are put through their paces. From key fob buttons requiring at least 1,000,000 clicks, water submersion and dust-tight testing for IP class ratings, to extreme temperature shifts and cabin vibration simulation – the test laboratory leaves no stone unturned.

Timo says that the test laboratory started out with basic equipment and testing facilities, but has continued to grow to meet the demands of clients. However, the growing capabilities of the Test Laboratory had left the measurement equipment behind.

To complement the extensive testing laboratory equipment at Stoneridge a multi-sensor CMM was the most recent investment. Previously, an older CMM was used, but its repeatability proved to be a hindrance. The slow system offered low quality results with poor data analysis. This meant that measurement and inspection work was often sent back to the supplier.

A new CMM was required for taking control of inspection and measurement, thus saving vast amounts of time. However, the search for a CMM led the decision makers to discovering the possibilities and benefits of laser scanning.

Relying on suppliers for measurement and inspection after testingwith limited access to quality inspection tools, Stoneridge relied on

suppliers’ measurement capabilities to provide feedback and results.

Anti Laas, Mechanic Design Engineer at Stoneridge says, “Since every measurement is money, we ask suppliers to do it, but they take a lot of time. They have their own projects, like measuring for serial production… so, it’s a long queue. You have to wait a long time, and we no longer have that time”.

The benefits of owning a multi-sensor CMM, or any comprehensive measurement systems were previously unknown for Stoneridge. For the engineers, the cost of a top of the range system seemed too much for what use they would get from it. At that time, sub-contracting the measurement tasks back to suppliers was the best value for Stoneridge. However, as operations grew and it was no longer productive to be sending all measurement work out of the factory, the decision was taken to research the metrology market for a suitable solution.

Learning about the laser scanning capabilitiesTimo Jakimainen led the search for the new equipment, alongside his colleague Anti Laas. Although the initial search was to find a modern, accurate and productive CMM, it was Anti’s knowledge of laser scanning that opened up a whole new range of possibilities. Anti explains that with a CMM and touch probing, data isn’t always useful. You don’t have the whole picture, you are basing what you know on a few points, a few dimensions. In some cases, information in this format can be manipulated to provide the results required. Therefore, due to the lack of full 3D data, it fails to reveal problem

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“ Creating part programs is very easy. The program will last for as long as the part is in production. The program is always there. Ready to use".Timo Jakimainen, Senior Engineer at Stoneridge.

Image 1. The LC15Dx scans the plastic automotive assembly.

Automotive supplier identifies mystery error using Nikon laser scanner

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Timo recalls the occasion when he travelled to Belgium to meet with the Nikon Metrology team. He explains that the round trip included a selection of other CMM/laser scanner providers. The meeting with Nikon showcased the benefits of laser scanning, including the ability to scan dark or metallic reflective surfaces with effective pointcloud acquisition.

With a much clearer picture of how the technology works, how reliable it has become, and what it could offer for the test laboratory, Timo and Anti knew that laser scanning technology was what they required. The optical image and data quality of the Nikon Metrology system for scanning the widest variety of parts is world class. Nikon’s state-of-the-art scanning technology sets it apart from the closest competitors as it provides the best scanning experience available today.

So, how does the new system fit in with activities in the Test Laboratory?Mechanic Design Engineer, Anti Laas sets forward the three main benefits of the Nikon LC15Dx, its speed, accuracy and 3D visualisation.

“Graphical reporting is a big benefit, you can simply show the supplier an image and ask about specific areas, and what can be done about it”, he says.

Timo adds, “The majority of measurements are done like this now. The laser scanner offers much more transparency”.

He continues to explain the broad spectrum of applications for the technology at Stoneridge. “We use it (the multi-sensor CMM)

areas of a component, often hiding or obscuring the bad areas of a part.

According to Anti Laas, “If you’re only taking a few dimensions, you don’t know what is going on in another area of the part. With a laser scanner, it gives you a more holistic view… the full picture”.Image 2 illustrates the problem which the team at Stoneridge found with using a CMM and how it was solved with the introduction of a laser scanner. This part failed tests multiple times, and the measurement results returned to show there were no problems, and it shouldn’t be failing. Still it failed. For the purpose of this component, the contacts were not required to be measured. The points used for measuring were around the base, but there were no problems found while the measurements added up. It wasn’t until the introduction of the laser scanner, that they noticed the issue. With laser scanning, you immediately see the whole picture. You immediately have visual representation of the part – as a whole – and you can see clearly where the problem is.

Timo summarises by saying, “with a laser scanner, you have much more transparency”.

What are the benefits of laser scanning?After initial project analysis and budgeting, some engineers weren’t convinced of the return on investment of using a CMM. It wasn’t until Stoneridge’s meeting with Nikon, that they began to understand the interesting benefits that laser scanning on a multi-sensor CMM could bring to the test laboratory.

“ If you’re only taking a few dimensions, you don’t know what is going on in another area of the part. With a laser scanner, it gives you a more holistic view… the full pictureAnti Laas, Mechanic Design Engineer at Stoneridge

Image 2. This part continued to fail tests and the problem could not be determined until the introduction of the LC15Dx.

Image 3. Graphical reporting is a big benefit at Stoneridge as it makes discussions about errors much simpler.

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for a lot of things. Not just one field, basically from day one of development to serial production, and ten years ahead, in quality issues this machine will constantly be used. Quality, development, design verification/prototyping, validation etc.”.

The Nikon system is useful for many departments and is used for a vast range of applications. One which is very important is ‘preventative measurement’. For this, a reference measurement profile will be created for a part which is mass-produced. The purpose of this test is to prevent line stoppages. With the measurement profile, they can take a sample from each batch, or once per month to closely examine the part and look for anything that isn’t quite right. If anything is found, they can contact the supplier and ask them to correct the issue, before it becomes a problem.

Installation and trainingThe ALTERA 10.7.6 CMM with LC15Dx laser scanner was installed in January 2017, followed by an intensive training. Since then Timo has already created many programs and has had a large amount of success using the machine, but he still believes he can learn more about the machine and reap more benefits.

“Creating part programs is very easy”, says Timo. “The program will last for as long as that part is in production. The program is always there, ready to use”.

Previously the test laboratory was responsible for many tasks, from the measurement, to analysing and presenting results. Timo jokes, that all he needs to do now is scan in a global comparison and hand over to Anti. With the offline dataset to analyse every aspect of the part, he now saves a lot of time for his colleague.

What results have been seen so far?Some immediate benefits that have been seen at Stoneridge include the non-contact measurement. Rubber key pads for controllers, and electronic key fobs were very difficult to measure before the introduction of the laser scanner. Timo explains that they did what they could, but had to explain to clients that they couldn’t guarantee the measurements were absolutely accurate. By applying pressure, the touch probe would deform the rubber part, making the measurement void. However with the LC15Dx, it measures not only with a contact free laser and camera system, but from a short stand-off which enables the scanner to access hard-to-reach areas and visualise them with high accuracy, comparable and closely correlating to touch probing accuracy.

The introduction of the Nikon Metrology system has introduced other opportunities aside from the normal line of work. Something which the engineers in the test laboratory are looking into is measurement before and after testing. Some of Stoneridge’s clients already demand this. After going through its standard tests for IP class rating, or other environment simulators such as vibration and extreme temperatures the components will be subject to testing to see how the part has changed.

The capability of the system is encapsulated by the amount of requests from outside of the company. Stoneridge has also been working with the local university – which also owns a Nikon system for referring people for one-off or sub-contract inspection. More and more requests are beginning to come in from Estonian companies to use the Nikon system.

However, for both Timo and Anti, they agree that one of the most useful functions for what they need is the full visual colour comparison. With all of the data available, it can be represented in easy-to-interpret reports, saved and shared at the click of a button. If ever there are problems, or something that went under the radar, they can bring up the report, check it and share it.

Image 4. Rubber key pads for controllers and electronic key fobs were very difficult to measure before the introduction of the laser scanner.