Synthesis and study of quasioptimal quick acting movement control of lifting cranes with a load on flexible suspension

Abstract

The subject of research is an influence pattern of quasioptimal quick acting movement control of lifting cranes with a load flexible suspension on dynamic movement characteristics. The purpose of the work lies in the synthesis of quasioptimal crane movement control when its accelerating with the elimination of load fluctuations, as well as in the study of the crane movement dynamics at the quasioptimal control. The paper proposed to switch from an optimal control of crane movements to control, which is described by a continuous function. In order to achieve specified final conditions of movement by the system “crane-load” an algebraic system of transcendental equations was composed, which was leaded to the target of minimizing the complex function of three arguments. By using the particle swarm method points in time were found at which there was a change in the control character (the driving force of the crane actuator). Simulation of crane movements at quasioptimal control made it possible to find its basic dynamic characteristics during acceleration. Comparative analysis of the data showed a significant reduction of dynamic loads in the crane elements. The transitional regime duration of the crane movement in comparison with the optimal control increases slightly. Thus, by increasing the duration of the crane`s non-essential movement cycle (for tens of seconds) an increase in the durability of the crane steel structures, mechanical gears, motor, power inverter, and other elements is achieved. The obtained results should be used for the development and modernization of movement control systems for lifting equipment, which require a significant productivity, energy efficiency and durability (for example, cranes that are extensively exploited in ports, metallurgical and machine-building enterprises, construction sites, warehouses).

Keywords

• lifting crane
• quasioptimal control
• maximum principle
• load fluctuations
• dynamic loads
• particle swarm method
• mathematical model
• transcendental equation