“…As stated earlier, the present contribution explores whether the adaptive estimation approach can improve the performance of SVSF-OBL in situations where the plant is nonlinear and its model is inaccurate. Although adaptive state estimators for linear plants have been known for quite some time, 9,[19][20][21] adaptive state estimators for nonlinear systems have recently drawn the attention of researchers. 2,6,8 For both linear and nonlinear adaptive state estimators, the broad classifications constitute process noise adaptive (Q-adaptive), measurement noise adaptive (R-adaptive), 7,20,22 and a combination of Q and R adaptive (QR-adaptive) estimators.…”