Design of adaptive controller and extremum seeking algorithm for quadrotors

Abstract

In this thesis, two tasks for quadrotors are presented. The first is an inner and the second is an outer loop control design for quadrotors. For the first task, an adaptive contoller for quadrotors is designed. During the design, it is assumed that all system parameters are unknown. Moreover, the wind disturbances are assumed as a finite sum of sinusoidal functions with unknown fre quencies, amplitudes and phases. It is proved that the equilibrium of the closed loop error system is stable, all signals are bounded and desired altitude and attitude control are achieved despite unknown wind disturbances and plant parameters. A simulation is performed to show the feasibility of the design. The advantage of the designed controller is shown by comparing with PID controller in an experimental setup For the second task, extremum seeking control theory is used. This theory enables to find the closest minimum or the closest maximum from a starting point in a function without having any foreknowledge about the function. In the experiment, this function refers to a nonlinear signal map created by a light source and it decays down from the source. The quadrotor has the ability of measuring the lux value in this signal map by a luminosity sensor. It measures the lux values in a circular line around itself as it is anchored to the floor. By using the measured value, extremum seeking is performed and the quadrotor is steered to the maximum lux value point (the front of the light source) on the circular line where the light sensor can travel on.