Topology Analysis And Design Of The Labelling Robot For Round Steel End Surfaces

Industrial robots have become an indispensable core device in the manufacturing industry since the 21 st century.In recent years,robots have been more and more widely used in the field of steel product labelling.For labelling robots used in the steel industry,traditional designs generally use a series mechanism structure,however,the series mechanism has the disadvantages of slow speed and relatively low precision.The parallel mechanism has the advantages of high speed and high precision,but has the disadvantages of small working space and poor flexibility,conversely the series mechanism has a large working space and good flexibility.Therefore,there is a complementary relationship between the series mechanism and the parallel mechanism.Combining the advantages of both and avoiding its shortcomings,it is the development trend of the mechanical processing industry to study the hybrid robot composed of series and parallel.In this article,by analyzing the requirements of round steel end face labelling of steel plant and the development trend of future round steel production process,a labelling hybrid robot for round steel end surfaces was constructed.According to the labelling requirements and analysis of output freedom,the structure of labelling robot should use hybrid mechanism,and three translational Degrees Of Freedom(DOFs)of labelling hybrid robot is realized by the parallel mechanism,two rotational DOFs is realized by the series mechanism.Using the topology synthesis method based on Position and Orientation Characteristic(POC)set,three candidate schemes for labelling robots are obtained;To ensure design quality of labelling mechanism,the fuzzy comprehensive evaluation method and analytic hierarchy method was applied for the optimal type selection of mechanism configuration scheme,the fuzzy decision set is obtained from the weight set and the evaluation matrix,and the schemes are sorted to complete the configuration;According to the preferred result,the preliminary structure design of the labelling robot is carried out,and the kinematics analysis is carried out.The solution of the hybrid mechanism is solved by the combination of two Monte Carlo methods;The whole of the hybrid mechanism is regarded as a series mechanism,and the parallel mechanism is regarded as one of the series joints,the jacobian matrix of the hybrid mechanism is obtained,and the optimization objective function of dimensional synthesis is obtained,unifying parameters in the objective function by the inverse kinematics of parallel mechanism and joint variable of series mechanism obtained by Monte Carlo,based on the pareto frontier method,the non-dominated sorting genetic algorithm with elite retention strategy is used to find the optimal value of multi-objective function;According to the comprehensive results of scale,the final structural design of the hybrid labelling robot is completed.According to engineering application scene of labelling for the round steel end surfaces of a bundle,topology analysis of labelling hybrid robot is carried out.The type of parallel mechanism of the hybrid labelling robot is optimized,the structure of the mechanism is designed and the kinematics and working space of the mechanism are analyzed,and the scale synthesis of the mechanism is carried out,and completed the final structural design of the round steel end surfaces labelling hybrid robot.