Research On The Comprehensive Performance And Its Multi-objective Optimization Design Of The Crane Telescopic Boom

Cranes are widely used in the fields of civil construction, transportation, port,chemical industry, metallurgy, water conservancy and so on. As the main loading partof the crane, the performance of the telescopic boom directly affects the performanceof the whole machine. However, current research mainly focused on the selection ofcross sections and lightweight design of the telescopic boom. The multi-objectiveoptimization of the telescopic boom considering strength, stiffness, fatigue life andweight is rare. Therefore, the optimization of the telescopic boom with static anddynamic performance, fatigue life and weight based on the parametric finite elementmodel, response surface method and global numerical optimization algorithms isstudied in this paper. The research contents mainly include:(1) Levels of structures optimization and recent developments of crane crosssections, design and optimization of crane booms and structural optimization based onapproximate models are briefly summarized.(2) A3D parametric model of the telescopic boom is constructed. Furthermore, afinite element model based on Contact Algorithm that considering the contact andfriction problem is established. Then, the static performance of the telescopic boom isanalyzed with the above model. A stress test of the structure is carried out, in order toverify the feasibility of the method used above and the accuracy of the finite elementmodel.(3) On the basis of static analysis, the fatigue life of the telescopic boom isestimated by using nominal stress approach. Dynamic properties of the telescopicboom are analyzed too.(4) Dimensions of the telescopic boom are taken as design variables. Then,optimal Latin hypercube design of experiment is used to establish the sample space,and the approximation model based on response surface function was built. Theoptimization mathematical model of the telescopic boom with getting higher firstnatural frequency under the first and the second working condition and lighter weightas the objective and meeting the strength, stiffness and fatigue life requirements asconstraints is conducted. Finally, the optimal design of the telescopic boom iscompleted based on the response surface model and Non-dominated Sorting GeneticAlgorithm (NSGA-П).This dissertation provides a theoretical support for the design and optimization of crane telescopic booms. Meanwhile, the multi-objective optimization approachproposed in the paper, which combines parametric modeling, FEM simulation, fatiguelife estimation and numerical optimization algorithms, can be a reference for othermechanical structure optimization.