ADAPTIVE STABILIZATION OF LATERAL MOTION OF A BALLOON GONDOLA

Two approaches to adaptive stabilisation of the undesired lateral moti on of the balloon gondola (the adaptive notch filter and the adaptive Butterworth filter which controls the phase of undesired oscillations) are reviewed, demonstrated and compared by simulations and laboratory experiments. This undesired motion is caused by asymmetric loading of the gondola, and is sensed by a simple magnetic sensor due to the ver tical component of the earth's magnetic field, With the adaptive Butte rworth filter a technique similar to Nussbaum's controller for the glo bal stabilisation of adaptive systems with unknown high-frequency gain s is proposed and used to stabilise the closed-loop system. Copyright (C) 1997 Elsevier Science Ltd.