The paper deals with problems concerning power gyroscopes for stabilization of vibro-izolation system. Two variants of gyro support with air drive were designed, namely with gas bearings and precision rolling bearings. Precession frame of the gyro is supported in aerostatic journal bearings to achieve minimum passive resistance. Some special phenomena, such as pneumatic instalibity, were found in some test regimes both at aerostatic thrust bearing of gyro support and aerostatic journal bearings of the frame support. However, with air inlet pressure level limited to value required for proper function of bearings, no instability was encountered.
Test stand for investigation of the influence of bearing bushing movement control on behaviour of a rigid rotor supported in sliding journal bearings was designed. The stand was equipped with two pairs of piezoactuators, enabling to move each bearing bushing in two directions, and with two pairs of relative sensors tracing shaft movement at both bearings. The initial tests showed quite unexpected phenomena, which should be cleared up, before experiments with controlled bearing bushing movement could be started. Finally the system began to operate according to predictions and it was possible to start intended experiments. Some results of the rotor behaviour with and without piezoactuator action are presented.