The Research Of The Double Eccentric Precision Adjustment Platform

In national defense, aerospace, automobile manufacturing, engineering industry andsome other areas, adjusting platform is a major means to achieve movement adjustment.In order to meet the needs of multi-dimensional precision adjustments in the limitedspace, in this paper, based on the operation principle of the double eccentric mechanism,modeling the adjusting platform analysis its system by using the hierarchical systemanalysis method and modular decomposition principle. Analyzed the dynamiccharacteristics of the double eccentric adjusting platform and it’s running track,proposed control theory based mode vector, and designed the double eccentricadjustment platform, and used the principle prototype doing some experiments.Based on the operation principle of the double eccentric mechanism, analyzed themovement of the double eccentric adjustment platform by using the vector analysismethod. After analyzed and compared three different types of double eccentricmechanism, select the equal-module vector double eccentric mechanism for theprogram design, achieved the positive and inverse solution of adjustment platform’sposition. Sited precision distribution of the double eccentric loops, which is thefunctional components of the adjustment platform by using differential method, anddetermined the component’s manufacturing precision.Aiming at the design requirements of the double eccentric adjusting platform andusing hierarchical and modular design strategies to determine the general scheme of thesystem design: The double eccentric components and the adaptively parallel mechanismwhich implement another three degrees of freedom adjusted are series connected.Through organic decomposition of the system, proposed solution to solve the four keyissues of the adjustment platform’s precision, stability, versatility and controllability: theeccentric loops and worm are arranged as a single entity in order to shorten thetransmission chain and enhance the precision; adjust the structural layout and materialsto improve stability, module design in order to ensure versatility, arrange sensors on themovement limited components through real-time feedback on the state of motion toachieve control of the system. Corresponding to the above key issues, elaborated thedesign of double eccentric loops, movement limited components, adaptive support andadjust components. Paper verified the correctness of the double eccentric adjusting platform’s model byusing the finite element method. Through kinematics numerical analysis of the doubleeccentric adjusting platform, verified the correctness of the design model’s trajectory.By kinetic analysis, obtained the model’s modal with and without prestress case, andachieved the platform’s deformation and natural frequency under load.The paper machined the prototype of the adjusting platform which depend ondouble eccentric principle, and conducted all degrees of freedom’s adjustmentexperiment, they verified the correctness of double eccentric adjustment platform’sadjustment principle, and the adjustment platform has a good dynamic adjustmentperformance.