Design of a Fixed-Wing UAV Controller Combined Fuzzy Adaptive Method and Sliding Mode Control

Table 7

Flight altitude controller performance indexes.

Methods	By the pitch angle			By the airspeed
Items	PID + SM	PID + FSM without f and	PID + FSM with f and	PID + SM	PID + FSM without f and	PID + FSM with f and
Steady time (s)	0.19	0.17	0.15	0.57	0.61	0.59
Steady error (m)	9.8	0.2	6.1	2.5	-2.2	0.1