Attitude Control Method for High-Precision Stage by Compensating for Nonlinearity and Coupling Arising from Euler's Equation and Coordinate Rotation

2014 ◽  
Vol 134 (3) ◽  
pp. 293-300
Author(s):  
Wataru Ohnishi ◽  
Hiroshi Fujimoto ◽  
Yoichi Hori ◽  
Koichi Sakata ◽  
Kazuhiro Suzuki ◽  
...  
2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Liang Zhuang ◽  
Zhang Yulin

The development of launch vehicles has led to higher slenderness ratios and higher structural efficiencies, and the traditional control methods have difficulty in meeting high-quality control requirements. In this paper, an incremental dynamic inversion control method based on deformation reconstruction is proposed to achieve high-precision attitude control of slender launch vehicles. First, the deformation parameters of a flexible rocket are obtained via fiber Bragg grating (FBG) sensors. The deformation and attitude information is introduced into the incremental dynamic inverse control loop, and an attitude control framework that can alleviate bending vibration and deformation is established. The simulation results showed that the proposed method could accurately reconstruct the shapes of flexible launch vehicles with severe vibration and deformation, which could improve the accuracy and stability of attitude control.


2020 ◽  
Vol 140 (4) ◽  
pp. 272-280
Author(s):  
Wataru Ohnishi ◽  
Hiroshi Fujimoto ◽  
Koichi Sakata

Author(s):  
Matteo Facchino ◽  
Atsushi Totsuka ◽  
Elisa Capello ◽  
Satoshi Satoh ◽  
Giorgio Guglieri ◽  
...  

AbstractIn the last years, Control Moment Gyros (CMGs) are widely used for high-speed attitude control, since they are able to generate larger torque compared to “classical” actuation systems, such as Reaction Wheels . This paper describes the attitude control problem of a spacecraft, using a Model Predictive Control method. The features of the considered linear MPC are: (i) a virtual reference, to guarantee input constraints satisfaction, and (ii) an integrator state as a servo compensator, to reduce the steady-state error. Moreover, the real-time implementability is investigated using an experimental testbed with four CMGs in pyramidal configuration, where the capability of attitude control and the optimization solver for embedded systems are focused on. The effectiveness and the performance of the control system are shown in both simulations and experiments.


2012 ◽  
Vol 06 ◽  
pp. 172-177
Author(s):  
Nam-Su Kwak ◽  
Jae-Yeol Kim

In this study, piezoelectric actuator, Flexure guide, Power transmission element and control method and considered for Nano-positioning system apparatus. The main objectives of this thesis were to develop the 3-axis Ultra-precision stages which enable the 3-axis control by the manipulation of the piezoelectric actuator and to enhance the precision of the Ultra-Precision CNC lathe which is responsible for the ductile mode machining of the hardened-brittle material where the machining is based on the single crystal diamond. Ultra-precision CNC lathe is used for machining and motion error of the machine are compensated by using 3-axis Ultra-precision stage. Through the simulation and experiments on ultra-precision positioning, stability and priority on Nano-positioning system with 3-axis ultra-precision stage and control algorithm are secured by using NI Labview. And after applying the system, is to analyze the surface morphology of the mold steel (SKD61)


2017 ◽  
Vol 26 (11) ◽  
pp. 1750175
Author(s):  
Changyuan Chang ◽  
Chao Hong ◽  
Yang Xu ◽  
Hailong Sun ◽  
Yao Chen

A constant voltage AC–DC converter based on the digital assistant technology is proposed in this paper, which has the advantage of high output precision. In this paper, a novel digital exponential wave generator is adopted in Constant Voltage (CV) mode to replace the normal triangle waveform to obtain a wider range of switching frequency, increasing the accuracy of output voltage under light load. The control chip is implemented based on NEC 1[Formula: see text][Formula: see text]m 5[Formula: see text]V/40[Formula: see text]V HVCMOS process, and a 5[Formula: see text]V/1.2[Formula: see text]A prototype has been built to verify the proposed control method. In PFM mode the deviation of output voltage is within [Formula: see text]% and the load regulation is [Formula: see text]%. Meanwhile, when the load jumps from light to heavy, the minimum output voltage could be maintained above 4.16[Formula: see text]V.


1954 ◽  
Vol 38 (325) ◽  
pp. 172
Author(s):  
K. E. Bullen

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