New sliding mode control for base-isolation buildings using fuzzy control of reaching law

Aim. The undue chattering effect is the major disadvantage of conventional sliding mode controllers used in Ref.4 by B. Zhao et al. We now present a new sliding mode controller that can, in our opinion, keep the chattering effect sufficiently low. In this abstract, we list the following three topics of explanation in our full paper: (1) the motion equation, (2) the determination of switching surface, (3) the design of control law. Under the third topic, we derive eq.(14) in the full paper as the control law; εFUZZY in eq.(14) is determined by Table 1 in the full paper; Table 1, though somewhat different from a similar table in Ref.6 by Liu, is based on Liu's experience. Finally, we take an eight-storey building's model as a numerical example to verify the effectiveness of our controller. In the hybrid controller, we use a rubber-bearing isolation base as passive control device, use a sliding mode controller designed with the fuzzy reaching law as active control device, and use Wen method for describing the nonlinearity of restoring force. Table 3 shows preliminarily that the calculated maximum displacement response and the calculated maximum acceleration response of the building's model are greatly reduced, thus suppressing the chattering effect of the sliding mode controller. It should be particularly emphasized that Fig.5(c) in the full paper shows preliminarily that our new sliding mode controller can keep the chattering effect sufficiently low.