If large machines and systems are already in operation, defects or incorrectly assembled components can lead to machine failure and thus to production stoppages and economic loss. For this reason, quality assurance prior to commissioning or after final assembly of plants and machines is of considerable importance. In order to recognize the correct assembly and function of machines reliably and without large expenditure, researchers of the Fraunhofer IZFP have developed an objective test solution, which can be used for the assembly final control as well as for the durable quality monitoring of moving or rotating machines and plants.
Machines and equipment generate characteristic vibrations and thus noises during operation. Since assembly errors or defects often cause a change in the “normal” operating noises, these vibrations provide information about the quality and correct operation of machines. Often the assembly personnel is entrusted with a good “hearing” and long experience with this testing task. Human hearing, however, is subject to a certain subjectivity: it tires after a certain time or is impaired by ambient noise. Available acoustic test systems often require adaptation or calibration, especially if the equipment or machines to be tested have to be changed only slightly in design.
The AcoustiX sensor system from Fraunhofer IZFP uses the data from individually adapted acoustic sensors, which are attached directly to the machine or record vibrations and noises of the respective systems contactlessly via microphones. Errors or irregularities are automatically analyzed and finally logged. Based on the signal evaluation, specific statements about the correct assembly and function of the system or machine can be made within just a few minutes.
AcoustiX has already been successfully tested by agricultural machinery manufacturer John Deere for permanent quality monitoring of combine harvesters and is currently being validated for series production. However, the sensor system is not only designed for monitoring cutting units. It can be used in all areas in which final assembly inspection or permanent operational monitoring are of considerable importance. Examples are the monitoring of large, autonomously operated machines and systems or the quality evaluation of individual assemblies, which are operated on test benches, among other things. Because a large part of the functionality is represented by algorithms, the sensor system can also be integrated into existing test systems and adapted to customer specifications without great effort, explained a Fraunhofer IZFP spokesperson.
In the future, the sensor system will provide even more information. The medium-term development goal of the researchers is exact fault localization and detailed determination of the type of fault using intelligent algorithms and analysis methods.
Further information: https://www.izfp.fraunhofer.de/en.html