When testing new motor products for any application, it is extremely important that prototypes are looked with a “fine tooth comb” before being put into production. All motors need testing to assure that they will perform as required, reliably. At Nidec Motor Corporation, as part of our leading-edge processes and testing methods, our state-of-the-art sound and vibration lab has a semi-anechoic chamber and reverberation chamber that are deployed as just two of the various tests performed routinely on our motors.
Both chambers are designed to isolate the product in question in an environment that is repeatable. This meaning that they both are designed to filter out external variables that would cloud proper calculations or measurements. Not only does this provide accuracy, but also speeds up the process of testing because engineers do not have to constantly adjust for background noise between tests. Both chambers, while having a similar goal, work in different ways.
Semi-Anechoic chambers are deafeningly quiet. With the name quite literally meaning “non-reflective, non-echoing, or echo-free", this chamber absorbs sounds and eliminates echoes to isolate the chamber from the outside environment. With motor testing, this isolation helps to gather precision sound from a source, the motor. The chamber construction is similar in design to the metal, double walled tumblers that we all drink from every day. This meaning that the chamber enclosure consists of two walls, separated by an air gap. Additionally, absorbing, soundproof material lines the inner walls, further insulating the chamber. For applications looking for sound or vibration, the sound source can be accurately measured from various directions.
A reverberation chamber, on the other hand, is designed to do the opposite of an anechoic chamber. Sometimes called an “Echo Room”, this type of measurement chamber is made to allow sound propagation that reflects off the hard, metal walls and bounces between non-parallel surfaces. The purpose of this chamber is to provide a more “real world” or realistic simulation that an anechoic chamber doesn’t provide. The chamber gives an idea of how, in our case, the motor functions within the cavity that it will be a part of in practice.