Every household has a variety of electrical devices such as electric hand mixers or power drills. In addition to a functionality and ease of use, the vibration or acoustic signature during use may influence consumer reviews and plays a major role in the final purchase decision. The customer’s poor subjective perception of the vibration and acoustic quality may even translate into poor perception of overall product quality.
Ergonomic and health criteria play a very important role, especially for professional users of rotating or striking hand machines. The machine vibrations are transmitted through the palm of the hand and the fingers into the hands and arms and cause hand-arm vibrations. With long-term exposure, these can lead to chronic complaints or illnesses, such as Raynaud’s syndrome, also known as “white finger disease”.
Scanning laser Doppler vibrometers from Optomet are very well suited to record the frequencies and amplitudes of all relevant vibrations. Thanks to the advanced infrared laser technology (SWIR), meaningful vibration measurements are possible even on rough and rotating surfaces such as saw blades, cutting or grinding wheels. The investigations make the spread of vibrations on the tool visible and, in cooperation with model calculations, provide the necessary information for suitable structural changes, such as damping or decoupling, which can reduce the vibration levels experienced by the user.