Mar 27 2006
What happens to a product after it leaves the factory? What stresses are placed on a mountain bike if the owner tackles a downhill slope or some steps on it? What engine speeds is an off-road motorbike likely to experience in practice? What is the magnitude and frequency of forces acting on the blade of a wind turbine? These are important questions for manufacturers.
"In the age of lightweight construction it is particularly important for manufacturers to know just how far they can push product design", explains Stefan Weiland from the Fraunhofer Institute for Structural Durability and System Reliability LBF. If you buy a motorbike, then lower weight translates into lower fuel consumption but in return the motorbike must not be any less safe than its heavier stablemate. Consequently it is important to know exactly which components can be used to save weight and where safety has already been pushed to the limit.
But how do you find out? The Darmstadt-based researchers are using a monitoring system to measurefor example forces during operation. "At the bike we measure the acceleration and the forces, and record these values on a memory chip", reports Stefan Weiland who will be presenting the bike at the Hannover Messe .The engineers from the LBF provide the bike fitted with sensors to test cyclists who then, for instance, cross the Alps on it. Back in Darmstadt the measurement signals are fed into a database and analyzed: how often did the cyclist have to make an emergency stop and what forces acted on the components as a result? The manufacturer also learns what terrain the cyclist encountered and how many jumps were involved.
Monitoring technology is not only useful for the cycle industry. Sensors can measure voltages in wind turbines: this data is compared online with preset parameters. If the maximum value is exceeded, the system automatically switches off. Monitoring costly machinery has also proven effective: a brown coal excavator due to be decommissioned after 20 years turned out to be up to the job nonetheless – still providing reliable service to this day.
http://www.lbf.fraunhofer.de/