FUZZY AND VARIABLE STRUCTURE CONTROL OF A CLASS OF UNDERACTUATED MECHANICAL SYSTEMS

This paper presents a fuzzy and variable structure control strategy for an acrobot, which is a class of underactuated mechanical systems. First, a fuzzy logic control ensures smooth and fast swing up control. Then, a fuzzy variable structure control is employed to ensure fast movement when the acrobot passes from the swing up area into the balance area. Finally, a model based fuzzy control, which is based on the Takagi Sugeno fuzzy model, is used to balance it over a large region.