Robust Sliding Mode Control-Based a Novel Super-Twisting Disturbance Observer and Fixed-Time State Observer for Slotless-Self Bearing Motor System. - Dich Quang Nguyen; Huy Phuong Nguyen; Duc Nhan Vo; Xuan Bien Nguyen; Satoshi Ueno; Shyh-Chour Huang; Van-Nam Giap (IEEE Access, 2022)