干渉の抑制を考慮した複数のフィードバック制御系の融合手法

抄録

A shaking table is a device used in vibration testing to investigate the vibration characteristics of structures. Currently, seismic waveforms used in vibration tests are recorded in acceleration. Therefore, acceleration feedback control is suitable for controlling shaking tables. However, while accelerometers have high measurement accuracy in the high-frequency range, they have low measurement accuracy in the low-frequency range. On the other hand, displacement sensors can accurately measure vibrations in the low-frequency range. Therefore, a method of constructing a single control system by fusing an acceleration feedback control system and a displacement feedback control system was considered. However, this method has a problem that the target tracking performance deteriorates near the frequency at which the control systems switch due to interference between the control systems. Therefore, this study proposes a method to suppress interference by using filters. Furthermore, we formulate the conditions for interference suppression and verify them through experiments using a one-degree-of-freedom shaking table. The results show that the influence of interference can be suppressed by designing the target tracking performance of the fused control systems to match near the frequency at which the control systems switch. And, the results show that characteristics that can suppress the influence of specimen reaction force can be obtained by reducing the phase difference of the disturbance suppression characteristics of the control systems to be merged near the frequency at which the control systems switch.