Electronics – Component Vibration

Every household contains a wide range of electrical appliances, such as electric hand mixers and power drills. In addition to functionality and ease of use, vibration and acoustic signatures during operation can influence consumer reviews and play an important role in the final purchase decision. A poor subjective impression of a product’s vibration and acoustic characteristics can even negatively affect the customer’s perception of its overall quality.

Ergonomic and health considerations are extremely important, particularly for professional users of handheld rotary or impact tools. Machine vibrations are transmitted through the palms and fingers into the hands and arms, resulting in hand-arm vibration. Prolonged exposure can lead to chronic symptoms or conditions such as Raynaud’s syndrome, also known as "vibration white finger".
Scanning Laser Doppler Vibrometer from Optomet are ideally suited for capturing the frequencies and amplitudes of all relevant vibrations. Thanks to advanced infrared laser technology (SWIR), meaningful vibration measurements can even be performed on rough and rotating surfaces such as saw blades and cutting or grinding discs. These analyses visualize how vibrations propagate through the tool and, when combined with modeling calculations, provide the information needed for appropriate design modifications such as damping or decoupling, which can reduce the user’s vibration exposure.

Practical Example

To make electric shavers more effective and comfortable, non-contact measurements are performed on individual blades and the handle. The influence of the battery charge level on blade movement across the skin can also be determined. This gives the manufacturer in-depth insight into the product’s operating behavior, enables more efficient development processes, and ultimately enhances the competitiveness of its products.

Laser vibrometers can also be used for final inspection. The non-contact measurement method of laser Doppler vibrometry avoids application errors that can occur with contact-based test methods. For example, uneven contact pressure from conventional sensors can affect the measurement. This influences the decision as to whether a test object meets the quality criteria, which are conservatively defined to account for measurement uncertainty. A better, more precise inspection method can reduce the number of rejected parts. The lasers used in Optomet SWIR vibrometers have a service life of more than ten years under continuous operation (24/7), reducing production-line downtime and maintenance costs. Multiple sensor heads can be connected to a single vibrometer with ease, and the individual channels can be read separately. Compared with tactile measurement methods, non-contact measurement significantly shortens cycle times; the resulting higher throughput reduces inspection costs while also delivering higher measurement quality.