Research On Accuracy Of Aero-engine Rotor Flexible Assembly Tooling

On account of the requirements of traditional Aero-engine assembly of high productioncosts and high accuracy, and Aero-engine flexible assembly tooling, which is more rapid,efficiency and accurate Aero-engine assembly, this thesis proposed the design philosophy ofparallel robot based flexible assembly fixtures for Aero-engine assembly and made analysison the accuracy. It was significant to solve the problem of aircraft engine assembly long cycleand low assembly quality.Firstly, the design requirements of Aero-engine assembly fixtures are analyzed, theconcept of flexible fixture design was done, a design scheme of flexible tooling foundationplatform was proposed, and the kinematics of parallel robot was analyzed. Then the flexiblefixture for the precision analysis and synthesis, Error model was established on the basis ofthe principle of independent function, Monte Carlo’s method were adopted to analysis thefactors affected the accuracy of flexible tooling geometry. Using particle swarm optimizationbased on interior point penalty function algorithm, accuracy synthesis was carried outaccording to the precision analysis of data obtained and objective function based onmanufacturing cost minimum. The result shows that: By applying the design method inaccuracy analysis and synthesis, the manufacturing tolerance of the parts was reasonable todetermine.To ensure that the design of flexible tooling satisfaction with the practice of aircraftengine assembly process, The paper also studied the flexible fixture calibration compensationmethod, the mathematical model of precision compensation was established, and a numericalexample shows the effectiveness of the proposed theory. Therefore, do find another effectiveway to improve precision of the fixtures. Because of the precision analysis did not considerthe effect of physical factors on the flexible fixture accuracy, In order to ensure the workquality of flexible fixture. In the end, the model of static stiffness of flexible tooling wasestablished.Using finite element method to simulate analysis of the load under the action of the simplified model under different conditions of strain, and the weak link of flexible fixtureswas found. This paper offers the theoretical basis in the process of flexible tooling.The project is innovative in the field of Aero-engine manufacturing digital assemble, thereason is that parallel mechanism was used as the basic platform of Aero-engine flexiblefixture. The method in this paper makes great sense on realizing the design of Aero-engineassembly and improving the positional accuracy of mobile platform.