Dynamic Modeling and Control of ARMG Spreader's Fine Tuning with Auxiliary Wire Ropes

The spreader of the automated rail mounted container gantry crane (ARMG) causes small offset or deflection oscillation because of the interference of random wind etc. so that cannot load and unload containers rapidly and accurately. This paper presents a fine tuning method by the traction of auxiliary wire ropes. The fine tuning system is simplified into a fully constrained 1R2T cable-driven parallel robot. The system dynamic model is established by Lagrange method, and the inverse dynamics solution is carried out by introducing the external force couple method. According to the real-time trajectory planning of spreader deflection, the position controller is designed based on computational moment method, and the simulation experiment platform is established by using MATLAB/Simulink based on dynamic model and servo control law. The interference force of wind and hoisting ropes is simulated by random signal to form the simulation closed-loop system. The simulation results show that the spreader can theoretically achieve the rapid and accurate positioning by the traction of auxiliary wire ropes after choosing the reasonable controller coefficients.