Research On Key Technologies Of Active Vibration Isolation Based On Air Spring

With the continuous updating of cutting-edge instruments and equipment for manufacturing and characterizing molecules and even smaller structures in laboratories,the objects of research have reached sub-nanoscale or even nanoscale,which puts higher requirements on the working environment of the instrument.At a certain level,these weak environments have become the bottleneck for the development and progress of science and technology.In order to meet the vibration requirements of the electron beam lithography system(EBL),this paper designs a distributed active vibration isolation platform based on air spring vibration isolation,through active vibration isolation to solve the low frequency vibration that passive vibration isolation cannot eliminate.Complete the overall design of the vibration isolation platform.Complete vibration source detection and analysis around the noise-free laboratory.Determine the structural plan of the vibration isolation platform and the support plan of the air spring.The feasibility of the platform structure is demonstrated through the analysis of the platform centroid and finite element analysis.Complete selection of key components such as MS series acceleration sensors and HG-C series displacement sensors.The detailed work flow and control principle of the vibration isolation system are determined.Complete the design of the hardware part of the vibration isolation system.The overall air circuit design of the air spring vibration isolation system and the design of the air source treatment system have been completed.The cleanliness of the gas processed by the air source treatment system has been significantly improved.The signal acquisition module design of acceleration sensor,displacement sensor and air pressure sensor are completed.Complete the design of main control module,high-speed solenoid valve output circuit design and host computer module design.Complete the construction of vibration isolation test and evaluation system,including MI-7008 dynamic signal analyzer,Model 731A acceleration sensor and P31 sensor demodulator.Complete the theoretical modeling of the vibration isolation system.Complete the reasonable configuration of the single-axis acceleration sensor,and further solve the sensor measurement matrix.The layout of three sets of horizontal air springs and three sets of vertical air springs is determined,and the conversion matrix of the actuator is solved.Finally,the six-degree-of-freedom dynamic equation of the vibration isolation system with air spring as actuator is established and the simplified dynamic equation is obtained.Complete the active vibration isolation control algorithm design.The vibration transfer function of the compound feedback mode is solved,and the vibration transfer curve under the compound feedback mode is drawn and analyzed.Secondly,the compound feedback control algorithm is applied to the designed air spring vibration isolation platform,and the compound feedback model of the air spring vibration isolation platform is established.This article focuses on the research of several key technologies of large air spring vibration isolation platform.This article mainly completes the overall scheme design of the vibration isolation platform,related hardware design and theoretical modeling of the vibration isolation system,etc.,which lays a solid theoretical foundation for the later active vibration isolation control system design and field debugging.