“…Linear control schemes such as proportional–integral–derivative (PID) (Bouabdallah et al, 2005), linear–quadratic regulator (LQR) (Foehn and Scaramuzza, 2018; Hoffmann et al, 2007), and H ∞ (Raffo et al, 2010) have been developed to stabilize the vehicle during hover, and these techniques assume a linearized robot model. Nonlinear flight control has been developed using feedback linearization (Lee et al, 2009; Mokhtari et al, 2006), NMPC (Neunert et al, 2016), backstepping (Bouabdallah and Siegwart, 2005; Guo et al, 2018; Hamel and Mahony, 2002; Klausen et al, 2017; Mebarki et al, 2015; Serra et al, 2016), and geometric control to deal with the nonlinear dynamics (Bry et al, 2015; Liu et al, 2018; Loianno et al, 2017; Mellinger and Kumar, 2011; Mellinger et al, 2012; Thomas et al, 2016b; Watterson and Kumar, 2018). In backstepping control, the translational and rotational dynamics are stabilized automatically instead of canceling the nonlinear terms as in feedback linearization (Härkegård and Glad, 2001), but the convergence of the position errors depends heavily on, and are limited by, the speed of convergence of the attitude error (Thomas et al, 2016b).…”