Study On Motion Characteristics For The Grab Bucket Of The In-unload Door Crane

The door cranes are the main equipment for loading and unloading in wharf, the capability of it has greatly deep influence on loading and unloading efficiency. In order to promote the loading and unloading efficiency of door crane, it is very important to design the luffing system, and the advantages and disadvantages of the luffing system have crucial influence on the movement capability, reliability and economicy of the crane as a whole.Based on the limitations of the traditional cantilever door crane which can not unload goods in the internal portal frame, the thesis puts forward to design a new type of the in-unloading door crane. The main operating mechanisms of this crane are:the traveling mechanism, the luffing mechanism and the hoisting mechanism. The core technology of this crane adopts a new luffing system and so the technical parameters and work performance of this crane are superior to the traditional door crane. The thesis has related research on the motion characteristics of grab bucket of the in-unloading door crane.The thesis consists of the following parts:(1) Research the constitute, working principle and the characteristics of luffing system of the in-unloading door crane. Through analyzing and calculating of the program, it obtains the horizontal displacement curve, the dead weight imbalance rack force curve and the goods imbalance rack force curve.(2) Deeply research the motion characteristics of this new crane in the luffing process. Use the plural vector method for analyzing the position, velocity and the acceleration of luffing mechanism. And base on the examples analysis for motion planning of the luffing platform, using Matlab software analyzing and calculating, it obtains the motion curve of the cantilever frame and the grab bucket.(3) Base on the principle of Lagrange equation, it sets up the mathematical model of the grab bucket swing system for this crane. Use the fourth Runge-Kutta algorithm to solve the mathematical model of the grab bucket swing system. And discuss the swing characteristics of this crane through changing the cord length and damping coefficient. It gets the grab bucket swing characteristic curve.(4) Combined with3D modeling Solidworks software and dynamic simulation ADAMS software, it sets up the virtual prototyping model of the grab bucket swing system for this new crane. By using numerical calculation and multi-rigid-body dynamics simulation calculation and changing the cord length and damping coefficient, it gets the grab bucket swing characteristic curve. Using virtual prototype technology can reduce the repeated work for traditional design process, reduce development costs, shorten the development cycle and improve the quality of products.