Dynamics Analysis And Anti-swing Control Of Cranes

Crane is an integral part of mechanical equipments in the modern production. It is widely appliedin various production areas, which has realized the production mechanization and has brought economicbenefits. But the crane in the operation process will produce the load swing, which affects the efficiencyand safety performance seriously. In order to ensure the crane could work safely and efficiently, aneffective control method must be designed to suppress the swing. Based on the above background, thedynamics analysis and anti-swing control of cranes are studied in this thesis.This thesis focuses on the study of the relatively complicated tower cranes and boom ones. Thecorresponding three-dimensional nonlinear dynamic models are established. The dynamiccharacteristics of the systems, which include the response of systems, the phase diagram and the motiontrajectory, are analyzed by using the MATLAB software when the systems are in different operationsand under different initial conditions. As a consequence, the motion properties of the systems undervarious external conditions are uncovered.Based on the systems’ accurate model, the time-delayed position feedback control is designed. Andthe control equations are derived in terms of the forms of movement of two systems. The results showthat the equations are nonlinear, neutral delay differential ones. According to the characteristics of theequations, the stability analysis of the systems can be conducted by the method of stability switches.Both the stability region and the relationship between the control parameters and the system dampingare obtained. These can provide a theoretical basis for selecting the appropriate control parameters.In order to verify the effectiveness of the control method, the DDE Solver program based onFORTRAN language is adopted, and the numerical simulation is performed to evaluate the controlbehavior with a comparison to that of the uncontrolled systems. The results show that, when twosystems are in different forms of movement and under different initial conditions, the presentedcontroller can suppress the load swing of the systems effectively, regardless of the impact of the systemson outside disturbances.