Tough enough?
Small RLDA teams counts on this highly efficient solution to perform over 25 campaigns annually
Tenneco, a US-based tier-one supplier of exhaust systems for the automotive industry, recently acquired two LMS SCADAS Durability Recorders for its Emission Control Europe engineering center located at the Heinrich Gillet plant in Edenkoben, Germany. Southwest of Mannheim, this is Tenneco’s major European production plant and the main European research and development facility as well.
How does one test the durability of an exhaust system? Not really a question that you ask yourself everyday, unless you happen to be a member of the Road Load Data Acquisition (RLDA) team at Tenneco’s Gillet plant in Edenkoben, Germany. This team faces the daunting task of exhaust system durability testing on a daily basis.
Daunting?
You wouldn’t think it, but the pressure is enormous. Exhaust systems need to last more than 10 years while still
meeting tighter-and-tighter emission regulations. And, obviously, most of them are exposed to extreme conditions. To meet these tougher-than-tough requirements, exhaust manufacturers perform a variety of durability tests, collecting measurements on both proving grounds and public roads according to potential usage cases. To do this, the Tenneco RDLA team instruments numerous measurements points on the exhaust system using a multitude of sensors to retrieve any combination of strain, displacement, acceleration, temperature, tacho, CAN and GPS data.
Sounds like a piece of cake? Not really. Not only does each campaign last on average 2 weeks, there are over 25 campaigns a year. With each campaign requiring larger and larger amounts of data in shorter and shorter timelines, extreme flexibility is required from the small 4-person team who needs to deliver top productivity and perform even more measurements than ever. That’s why the team needed the most flexible and reliable data
acquisition system for the job. And they did their homework, selecting the best option on the market.
“By design, it had to be a compact, robust, easy-to-use data acquisition system. We have little space to
accommodate systems in the vehicle and we want to avoid complex cabling, too,” said Dr. Zhijun Wang
RLDA Group leader at Tenneco. Mr. Klaus Rieger, RLDA engineer, added, “After a thorough benchmark, we
selected the LMS SCADAS Durability Recorder. The LMS solution really offers the best price-quality ratio of all
solutions we examined.” We particularly valued the compact size and the robustness of the system, the flexibility
to connect a broad range of sensors and the ease of use of the software for test preparation and validation.”
Saving valuable time on durability testing campaigns
So how exactly does the a durability test work? At the beginning of each campaign, the team receives the prototype vehicle from the customer. Then, the prototype is instrumented inside the Tenneco facilities. A detailed and finicky part of the campaign, this process can last up to one week. Part of this process is mounting the LMS SCADAS Durability Recorder. Since the connection points are located on the front of the equipment, it is an easy to hook all sensors onto the hardware. Even very complicated set-ups take less than a day. In parallel, the team prepares the test itself. Thanks to the easy-to-use LMS Test.Xpress software, there is a concrete time gain. With the previous software, it took 4 hours and now the test set-up time with the LMS solution is less than 45 minutes. After then, there is typically an additional confirmation check on-site to validate that everything is working before driving the car to the proving ground.
No-fail policy on the proving ground
On the proving ground is where data acquisition reliability really matters. An average campaign can take from one day, up to a week. And in this period the two technicians testing the car need to retrieve all the essential data. From time to time there is no possibility for a second run if parts of the channels were not correctly measured or critical events were missed. At the end of the test, the instrumentation and the prototype are
stripped off and the vehicle is shipped back to the manufacturer directly from the proving ground – in most cases for further scheduled tests. This is where the lightweight and compactness of the LMS data acquisition systems is a real asset. All the technicians need to do is dismantle them, load them in their cases in the trunk, and drive them back to Tenneco and call it a day. Additional hours to break down a set-up and cart around the system isn’t necessary.
144 channels of flexible data acquisition
With 144-channels split between two units, the Tenneco LMS SCADAS system uniquely combines strain-based,
vibration and displacement measurement capability in one single module: its VB8 is the most versatile solution for durabilitytype measurements campaigns.
“With one universal module, we are able to measure any type of data on any channel without extra cabling or adapters. Whether we need to acquire additional strain data here or get more information about vibration levels
using accelerometers, it can all be done instantaneously. Switching cable between modules is not necessary
anymore. This saves hours of valuable testing time and gives us the extra flexibility to help us meet the
toughest deadlines,” said Dr. Wang.
And the system can retrieve information such as speed or rpm from the vehicle’s CAN-bus. “We foresee numerous possible applications to compare acquired data with CAN data. For example, this helps us to understand at which speed the resonance appears,” added Mr. Rieger.
A more important function is the GPS. The GPS signal helps retrace information in case a marker is missing. It helps answer the question: where did this specific event happen? Was there a curve or a slope? The GPS integration is extremely precise and reacts dynamically. “The GPS functionality in the LMS SCADAS Recorder is a very attractive feature. I am certain of my measurements since I know that the test run has been marked with GPS data,” clarified Mr. Rieger.
Security guaranteed
The LMS solution is really plug-and-play. Since the unit is completely integrated, it is a very reliable system; there is no risk of failure due to a disconnected adapter or loose cables flying around. With master-slave connectivity, the systems connect directly via an optical cable. Another big advantage is the immediate data synchronization,
which eliminates possible errors associated with manual synching.
“We have only a very short time to measure our data. We need to validate the data on the spot. With real-time
signal calibration and quality checks, like the one-button LMS SCADAS Smart Control, I can concentrate on
the measurement and not bother about anything else. It makes testing quite a lot of fun,” concluded Mr. Rieger.
“With such a flexible and efficient solution, our RLDA team can guarantee quality test results for every single
one of our more than 25 campaigns annually. When we opted for LMS, we clearly did not only purchase a
data acquisition system, we acquired the right tool for our job. This is why partnering with LMS is the correct
choice for us,” concluded Dr. Wang.
