Method of Measurement of Angular Velocity in Miniature Devices

Abstract

The method and system for measuring angular velocity, particularly suitable for use in miniature drive systems, are presented. This applies, for example, to drive systems with direct current micromotors with mass moments of inertia of rotating assemblies up to several tens  g · cm² and electromechanical time constants of the order of several tens of milliseconds. This is without the need to connect additional rotating elements to the mechanical structure of the drive. The analogue output signal is obtained by loading the input of the integrating two-port network with rectangular pulses of constant length, obtained after detecting radiation reflected from a rotating surface. The paper presents the performance of the physical model of the transducer and simulation studies indicating the possibility of optimizing the dynamic parameters of the system. Reducing the time constant of the two-port network resulted in a reduction of the time constant of the transducer (for example, a two-fold reduction of the quad constant resulted in a five-fold reduction of the transducer response time constant). Increasing the number of pulses per revolution while reducing their amplitude results in a reduction of the pulsation level in the output signal.