List of Symbols and Acronyms

DASC Time-delayed anti-swing controller FHL Force transferred from the load to the helicopter kd Gain of the delayed feedback controller L Load cable length mL Load mass MHL Moment transferred from the load to the helicopter N Number of particles in the PSO PSO Particle swarm optimization algorithm RH Hook position vector RL Load position vector p,q,r Helicopter angular velocities Vmax Maximum velocity of PSO u,v,w Helicopter velocities x,y,z Helicopter center of gravity position , , Euler angles L, L Load swing angles d Time delay 1, 2 PSO learning factors INTRODUCTION