“…They are optimally designed for only typical working conditions (Bottasso et al, 2012), which renders it unable to meet different damping requirements for helicopter in different working scenarios like takeoff, flight, landing, and taxiing. As an intelligent material, magnetorheological fluid (MRF) can change its rheological properties in milliseconds under the presence of external magnetic fields, and the change is continuous, controllable, and reversible (Bai et al, 2019; Cheng et al, 2018; Yu et al, 2016). The advantages such as high yield stress, wide damping amplitude modulation, short response time, and good stability of MRF make it possess extensive application in helicopter (Gandhi et al, 2001; Zhao et al, 2004), building (Cesmeci et al, 2019), vehicle (Ha et al, 2013; Oh et al, 2019), and other fields (Bai et al, 2015; Choi and Wereley, 2008; Weber, 2014).…”