Effects of wind-induced tall building vibrations on a tracking task

Motion simulator experiments were conducted to study tracking task performances in 12 low frequency fore-aft sinusoidal motion conditions that comprise low, medium and high acceleration amplitudes (8, 16 and 30 mG) and 4 frequencies: 0.125, 0.25, 0.5 and 1.0 Hz, which are typical of wind-induced tall building motions. Test results indicated that aiming performance of tracking tasks that require high level of aiming accuracy is frequency dependent and generally decreased when acceleration amplitude of low frequency fore-aft sinusoidal motion increased. However, aiming performance of tracking tasks demanding low aiming accuracy is frequency dependent and was degraded only in high acceleration amplitude conditions. It demonstrated that aiming performance are frequency dependent in some acceleration amplitude conditions and also depends on an aiming accuracy level. The results also demonstrated that the effects of fore-aft sinusoidal motions on the variation of vertical component of a laser light spot location are greater than horizontal component, attributing to, at least in part, the stance adopted by the test subjects, with their legs one should apart, which provided better stability control in the lateral than in the fore-aft direction.