The principle of inertia vibrometer. Various schemes vibrometer with inertial mass vibroprobe, drawings.
Tensoresistance inertial vibration transducers (vibrometers) can be built according to the schemes of accelerometers and differ from the latter only by the ratio of natural frequencies and frequency processes studied. Since the inertial mass vibrometer relatively more, and amplitude range should match the measured amplitude of the vibrations, the design concept of low-frequency vibrometer and accelerometers are also somewhat different. In Fig. а), and a scheme of the inertial vibrometer, which is based on the flywheel bearings. Weight is kept in balance spring elastic elements (springs) and its movement causes deflection displacement transducer. Vibrometers this design can have the natural frequency of a few hertz.
Vibrometer with the inertial mass of the pendulum as shown in Fig., б). Inertial mass of the lever is held in equilibrium by two springs or elastic sensors displacement transducers. In Fig. в), shows the vibrometer with contact-type sensor element vibration transmission through the rod. In measurements of body vibrometer are holding or are mounted on a fixed support.
For low-frequency characteristic vibrometer zero reading some instability due to the effects of friction in the bearings, causing restriction of range.
In the study of plants used as vibroprobe contact type, which binds to the object of study and any fixed support. As vibroprobe almost tensoresistance can use any type of displacement transducer, measuring range corresponding vibro research object. Kind vibroprobe contact type are hand vibroprobe. In the measurements, the operator holds the body vibroprobe in hand, pressing the tip to the object of study so that tensoresistance displacement transducer was in a position corresponding to the middle of the range.