Quantitative feedback controller design and test for an electro-hydraulic position control system in a large-scale reflecting telescope
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For the primary mirror of a large-scale telescope, an electro-hydraulic position control system (EHPCS) is used in the primary mirror support system. The EHPCS helps the telescope improve imaging quality and requires a micron-level position control capability with a high convergence rate, high tracking accuracy, and stability over a wide mirror cell rotation region. In addition, the EHPCS parameters vary across different working conditions, thus rendering the system nonlinear. In this paper, we propose a robust closed-loop design for the position control system in a primary hydraulic support system. The control system is synthesized based on quantitative feedback theory. The parameter bounds are defined by system modeling and identified using the frequency response method. The proposed controller design achieves robust stability and a reference tracking performance by loop shaping in the frequency domain. Experiment results are included from the test rig for the primary mirror support system, showing the effectiveness of the proposed control design.
KeywordsLarge-scale reflecting telescope Quantitative feedback theory Electro-hydraulic position control system Micron-level position control capability System identification Robust stability
CLC numberTH137 TP13
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- Ahn, K.K., Truong, D.Q., Soo, Y.H., 2007. Self tuning fuzzy PID control for hydraulic load simulator. 6th Int. Conf. on Control, Automation, and Systems, p.345–349. https://doi.org/10.1109/ICCAS.2007.4406935Google Scholar
- Bender, F.A., Sonntag, M., Sawodny, O., 2015. Nonlinear model predictive control of a hydraulic excavator using Hammerstein models. 6th Int. Conf. on Automation, Robotics and Applications, p.557–562. https://doi.org/10.1109/ICARA.2015.7081208Google Scholar
- Knohl, E.D., 1994. VLT primary support system. SPIE, 2199: 271–283. https://doi.org/10.1117/12.176196Google Scholar
- Moeinkhah, H., Akbarzadeh, A., Rezaeepazhand, J., 2014. Design of a robust quantitative feedback theory position controller for an ionic polymer metal composite actuator using an analytical dynamic model. J. Intell. Mater. Syst. Struct., 25(15): 1965–1977. https://doi.org/10.1177/1045389X13512906CrossRefGoogle Scholar
- Stepp, L.M., Huang, E., Cho, M.K., 1994. Gemini primary mirror support system. SPIE, 2199: 223–238. https://doi.org/10.1117/12.176192Google Scholar