Vibratory Gyroscope

an instrument for determining the angular velocity of an object; contains vibrating parts that react to the object’s rotation. There are bar and rotor types of vibratory gyroscope. The sensing element in the bar type is formed by several vibrating objects similar to the bars of a tuning fork.

A bar-type vibratory gyroscope now in practical use is the so-called girotron (see Figure 1). Its sensing element is a vibrator consisting of bars, an elastic torsion bar that joins the bars to the base of the vibrator, and a plate that is rigidly attached to the torsion bar and that moves within the field of the coils, which are mounted on the base. The prongs of the tuning-fork vibrator are vibrated by means of a special electrical circuit. If an object, together with the base of the vibrator, rotates around the axis O£ with an angular velocity o>£ a moment of Coriolis forces of inertia appears, which causes the vibrator to develop torsional vibrations around the axis 0£. In addition, the vane vibrates between the coils; the amplitude of the vibrations is proportional to the angular velocity w . The value of oj£ is determined from the coils by radioelectronic methods. The instrument has a number of advantages: the absence of gimbals and rotating or rubbing parts, the presence of one axis of sensitivity, the linearity of its reading, and its high reliability.

Figure 1. Sensing element (vibrator) of a girotron

The principle of operation of the rotor-type vibratory gyroscope is analogous to that of the bar-type, except that a revolving rotor with an elastic suspension rather than the bars and plate is used as the vibrating element. However, the development of the vibratory gyroscope involves a number of technical difficulties.

There are a wide variety of possible applications for vibratory gyroscopes; the simplest is their use in measuring the angular velocity of an object. They can also be used in gyroscopic stabilizing systems, inertial navigation systems, and other fields of gyroscope technology.