Looking with sound. A new way to investigate product improvements and pinpoint failures. Also preventively. For this purpose, Sorama Sound Imaging developed a patented sound camera with a wide range of applications. With that camera, it is possible to listen very precisely to an object or an environment. A 3D image can be built from that sound and frequencies and sources can be filtered out.
The main objective for Sorama was to eliminate noise pollution. This can be divided into two aspects: detecting where noise is coming from and tackling the source. Or, during product development, ensuring the best possible acoustic design.
Ventilation system
We see a wonderful application for this when optimising a ventilation system. Macawi asked Sorama to help design this system, which should produce a maximum of 40 dB(A) noise at 40 mBar. By looking at noise from vibration, air vibration and the motor, and then analysing those images, various design improvements could be made. As a result? A noise level of 34 dB(A) at an air output as low as 90 mBar.
First, the various noise sources were mapped and analysed. Sound was found to come from the motor, the housing, the airflow from the hoods and from the seals. Piece by piece, the sources were optimised to arrive at the final result. In intensive care in particular, it is important that equipment produces as little noise as possible.
Harmful
But sound is not only a phenomenon that can be avoided with the help of this technology, but also one that can be used to enable preventive maintenance, for example, and - another completely different application - can be used to maintain public order. Scholte: "Sometimes sound is pleasant, sometimes irritating and sometimes harmful to health. Think of noise from cars, buses, scooters, planes, etc. People don't realise it, but too much noise can cause too much stress in your body, which is not good for your health. For instance, one in five Europeans sleep poorly because of noise pollution. Noise pollution is the second biggest threat to public health in public spaces after air pollution."
Visualisation
The Sorama CAM, as the sound camera is called, is a screen with many microphones capable of visualising sound. The image generated is somewhat similar to that of a thermal camera. By visualising sound, you can see what the source of the sound is, where it starts (in a product or in a room) and how it travels. With this knowledge, you can take measures, for example, in the case of a motor, compressor, hoover, generator, etc., to adjust the design so that it produces less noise.
Well-known companies now working with a Sorama CAM include DAF Trucks, Inalfa Roof Systems, NXP, VDL, Bosch VDT, Webasto, Demcon and Philips. Sorama is currently working on a new application: preventive or predictive maintenance. "We want to deploy the Sorama CAM to detect wear of parts in a product. For example, the wear of bearings or gears in a compressor or in a pump or gearbox. So you can see when a product or part needs to be replaced. That way you don't have to wait until the last moment and you can work in a planned way." While we are in touch with Rick Scholte, founder of Sorama, to establish this story, he hands it over to his colleague Ton van Oort. The reason: Scholte's phone is nearly exploding with congratulations, as the previous day he received the Prins Friso Ingenieursprijs 2017! A peer award instituted by the Royal Institute of Engineers (KIVI). A recognition of the extraordinary innovativeness of his invention!
By: Janet Kooren
Pictures: Sorama Sound Imaging
