Research On Control System Of MOEMS Based Electromagnetic Scanning Grating Micromirror

The MOEMS based scanning grating micromirror is the new generation of core spectroscopic component for spectrum detection and analysis equipment.It has the salient features of spectroscopic and scanning functions,small size,low cost,and can be used to replace array detecto with single-tube detector.The control system of scanning grating micromirror is an indispensable and important part of scanning grating micromirror to work with high precision and stability.The thesis carries out the study on the key technologies of high-precision closed-loop control system of the MOEMS based electromagnetic scanning grating micromirror,which has important scientific significance and urgent application requirements.Based on the analysis of the research status and the main problems of the control methods of scanning micro mirror and scanning grating micro mirror at home and abroad,the structure and working principle of the MOEMS based electromagnetic scanning grating micromirror and the integrated angle sensor developed by the Microsystem Research Center of Chongqing University are studied and analyzed in this thesis.In the research of a new closed-loop control method based on integrated angle sensor signal,a new frequency modulation algorithm for tracking the resonant frequency of scanning grating micro mirror in real time is proposed for the first time.The simulation model of Fuzzy-PID controller is established,and the design and simulation verification of control algorithm are completed in this thesis.The framework of the closed-loop control hardware system of the scanning grating micromirrors is proposed,and the software system design of the control system is completed.Finally,a corresponding test platform is set up to complete the test of the control system hardware circuit,and the comparison test of electromagnetic scanning grating micromirror in open-loop and closed-loop sates.The test results show that the tracking accuracy of the MOEMS based electromagnetic scanning grating micromirror control system developed by this thesis is 0.1 Hz.When the half-angle of the mechanical scan is 7 °,the system control accuracy reaches 0.03 °.The steady-state error is reduced from 0.924% of the open-loop to 0.158.Compared with the open-loop state,the long-term stability and temperature stability are increased from 1.19% and22.26% to 0.15% and 0.23%,respectively.The MOEMS based electromagnetic scanning grating micromirror control system developed in this thesis can basically meet the application requirements.The main works of the thesis are listed as follows:(1)The research status and existing problems of scanning micromirror and scanning grating micromirror control methods at home and abroad are analyzed.According to the application requirements of MOEMS based electromagnetic scanning grating micromirror,the research objectives and contents of this thesis are determined.(2)The related theoretical models of the MOEMS based electromagnetic scanning grating micromirror and the integrated angle sensor are studied,and the system transfer function is solved.The structure and working principle of the Fuzzy-PID controller are studied,and the overall framework of the scanning grating micromirror closed-loop control system is proposed.The closed-loop control model is built and simulated based on Matlab/Simulink,and the design and optimization of the core control algorithm are carried out.(3)The hardware system framework based on the DSP main control chip and the components of each sub-module are designed.Based on the circuit simulation software Multisim,the designed circuit is simulated,verified and optimized.The design and processing of the board-level circuit are completed.(4)The overall framework of the software system is established.The structure,functions and interfaces between the sub-modules of the software system are designed.Based on the CCS and VB.NET development environment,the embedded software of the lower computer and the client of the upper computer of the control system are compiled,debugged and simulated,respectively.The burning and release of the software system is completed.(5)The test method is analyzed,the test plan is formulated,and the corresponding test platform is built.The electrical performance test of the control system hardware circuit,and the performance comparison test of the MOEMS based electromagnetics canning grating micromirror in open-loop and closed-loop state are completed.The comparison test of spectral stability of the broadband micro-NIR spectrometer is carried out.The processing and analysis of the test results are completed.