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adaptive controllers are proposed to control fixed-wing unmanned aerial vehicle attitude for both longitudinal and lateral motions simultaneously. A full-order nonlinear model of the aircraft, where actuator dynamics are considered, is used to design the proposed controllers. The different motion objectives of the aircraft were controlled via separate control loops. Based on the gap metric concept analysis, two single-input single-output controllers were used for the longitudinal motion and one multi-input multi-output for the lateral motion. For each loop, a suitable structure adaptive controller was designed, and the coupling between the loops was treated as a time-varying uncertainty. The full-order nonlinear model with the proposed controllers was used to simulate the system to evaluate the closed-loop performance. The simulation results show that the controllers ensure that the system outputs asymptotically track the outputs of an ideal system. The overall performance of the proposed controllers is drastically improved compared to that of standard PID controllers. INDEX TERMSAttitude control, Autonomous vehicle, adaptive controller (L AC), Unmanned aerial vehicle (UAV).

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This chapter presents a simple method to efficiently predict the rotor speed for a sensorless vector control technique applied to induction motors (IMs). The motor is supplied by a Simplified Split-Source Inverter (S3I), which provides dc-boosting and ac-inversion processes during input voltage sag. It also has a wider modulation range and a lower harmonic content than conventional boosting inverters. With this contribution, it is possible to efficiently estimate the rotor position directly without needing a PI controller with fluctuated supply voltage. The proposed strategy can be divided into three parts. The first uses a dual-loop controller to obtain the reference DC-boosted voltage of the SSI and regulate the input current. The second is the suggested observer for speed detection, which is derived from the principles of phase axis relations of the adopted machine currents and the indirect rotor flux orientation control (IRFOC) approach. With a newly developed space vector modulation, the third part will generate the switching pulses of the inverter switches. A complete analysis has been conducted to ensure the observability of the proposed technique. A series of PLECS simulations were conducted to verify the concept. The obtained results validate the proposed strategy with the S3I topology.