The coupled dynamic reaction force study of large-aperture piezoelectric fast steering mirror

2021 ◽  
Author(s):  
Bing Ran ◽  
Lianghua Wen ◽  
Licheng Zhu ◽  
Kangjian Yang ◽  
ping yang ◽  
...  
Keyword(s):  
Reaction Force ◽  
Dynamic Reaction ◽  
Large Aperture

scholarly journals Multi-objective robust optimization design for powertrain mount system of electric vehicles

2017 ◽  
Vol 36 (3) ◽  
pp. 243-260 ◽  
Author(s):  
Fu-Long Xin ◽  
Li-Jun Qian ◽  
Hai-Ping Du ◽  
Wei-Hua Li
Keyword(s):  
Robust Optimization ◽  
Permanent Magnet ◽  
Electric Vehicle ◽  
Electric Vehicles ◽  
Permanent Magnet Synchronous Motor ◽  
Reaction Force ◽  
Synchronous Motor ◽  
Dynamic Reaction ◽  
Optimization Scheme ◽  
Multi Objective

A multi-objective robust optimization scheme for the powertrain mount system of an electric vehicle is proposed in this paper. A permanent magnet synchronous motor model is established by taking account of the effects of magnetic saturation and space harmonics, in which the d–q-axis inductance and the flux linkage excited by permanent magnet were obtained by finite element method. The rippled output torque of the permanent magnet synchronous motor mixed with harmonic components is obtained with the New European Driving Cycle as the running condition of the electric vehicle. A six degree-of-freedoms (DOFs) powertrain mount system is established and the response of the system is obtained with the rippled torque as the excitation input. A multi-objective optimization model of the powertrain mount system is built with the stiffness’s of the mounts as the design variables, and with the goal of maximizing the decoupling rates and minimizing the dynamic reaction forces of the mounts acting on the car body. Genetic algorithm is used to conduct the global optimization and all the Pareto optimal solutions are found out based on the optimization theory, and the solution with the optimal robustness of dynamic reaction force is obtained by Latin hypercube sampling method. The results show that with the proposed multi-objective robust optimization scheme applied for the parameters optimization of the motor mount system, the decoupling rates increase obviously, the dynamic reaction force decreases apparently, and the optimization result shows good robustness. The optimization results can make the powertrain mount system of electric vehicles processing of optimal dynamic response characteristics correspondingly.

Numerical and Experimental Analyses of Static and Dynamic Characteristics for Partially Helically Grooved Liquid Annular Seals

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Keisuke Nagai ◽  
Kazuki Koiso ◽  
Satoru Kaneko ◽  
Hiroo Taura ◽  
Yusuke Watanabe
Keyword(s):  
Flow Rate ◽  
Dynamic Characteristics ◽  
Smooth Surface ◽  
Reaction Force ◽  
Leakage Flow ◽  
Dynamic Reaction ◽  
Static And Dynamic Characteristics ◽  
Whirling Motion ◽  
Leakage Flow Rate ◽  
Experimental Analyses

Numerical and experimental analyses of the static and dynamic characteristics of the liquid annular seals with axially partial helical grooves were conducted to investigate the effects of the axial length gal of a helically grooved section in a seal stator. The numerical solution and experimental procedures were applied in the same manner as in previous studies on through-helically grooved seals, wherein the grooves extend across the seal length. The numerical results qualitatively agreed with the experimental results, demonstrating the validity of the numerical analysis. The leakage flow rate Q was lower in the partially helically grooved seals than that of conventional through-helically grooved seals across a small range of rotor spinning velocities. In contrast, the reduction in Q due to the pumping effect caused by the spin of the rotor diminished with the decrease in gal. For a small concentric whirling motion of the rotor, the radial dynamic reaction force Fr and magnitude of variation in the tangential dynamic reaction force Ft with the whirling angular velocity increased with the decrease in gal, and their values approached the corresponding values for the smooth-surface seal. Under the same rotor whirling velocity, the Ft for the partially helically grooved seals became lower than that for the smooth-surface seal (similar to the case for the through-helically grooved seal), although decreasing gal tended to increase Ft. These results suggest that partially helically grooved seals can improve the efficiency and stability margin of the pumps because of the reduction in leakage flow rate and suppression of the rotor forward whirling motion (with large radial and tangential dynamic reaction forces) as compared to conventional through-helically grooved seals.

Analysis and Compensation of Reaction Force in Large-Aperture Piezoelectric Fast Steering Mirror

2020 ◽  
Vol 47 (6) ◽  
pp. 0601007
Author(s):  
冉兵 Ran Bing ◽  
杨平 Yang Ping ◽  
文良华 Wen Lianghua ◽  
杨康建 Yang Kangjian ◽  
王帅 Wang Shuai ◽  
...  
Keyword(s):  
Reaction Force ◽  
Large Aperture

scholarly journals Vibration Feedforward Compensation for Magnetically Suspended Control and Sensitive Gyroscope with Spherical Rotor

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Qiang Liu ◽  
Heng Li ◽  
Cong Peng ◽  
Sha Sheng ◽  
Zhaojing Yin ◽  
...  
Keyword(s):  
Centrifugal Force ◽  
Attitude Control ◽  
High Speed ◽  
Reaction Force ◽  
Magnetic Bearing ◽  
Dynamic Reaction ◽  
Optimal Sequence ◽  
Vibration Displacement ◽  
Control Moment ◽  
Working Principle

Magnetically suspended control and sensitive gyroscope (MSCSG) with two capabilities including attitude control and attitude measurement is promising in meeting the requirements of novel spacecraft. When the momentum vector of a high-speed rotor suspended in five directions is tilted by Lorentz force-type magnetic bearing, the instantaneous large control moment is obtained. The spacecraft attitude can be sensed by a high-speed rotor without deflection interference torque. In this paper, a novel MSCSG with sphere rotor is presented, and its spherical structure and working principle are introduced. The magnetic bearing-rotor dynamic model is established based on Newton’s second law and the gyrokinetic equations. The generating mechanism of three interferences, including bearing dynamic reaction force, deflection torque, and centrifugal force, is analyzed. The feedforward compensation control against three interferences for MSCSG is adopted, and the loading sequence of three interferences is simulated. The optimal sequence of bearing dynamic reaction force, deflection torque, and centrifugal force is used. The radial and axial vibration displacement amplitudes are reduced from 20.8 μm and 31.7 μm to 9.4 μm and 14.9 μm, respectively. The experimental results are in good agreement with the simulation, which indicates the MSCSG rotor unbalance vibration is suppressed effectively by the feedforward compensation method.

scholarly journals Evaluation of internal and external stresses on the SPT sampler

DYNA ◽  
2016 ◽  
Vol 83 (195) ◽  
pp. 229-236
Author(s):  
Juliana Zapata ◽  
Edmundo Rogerio Esquivel
Keyword(s):  
Internal Friction ◽  
Carrying Capacity ◽  
Reaction Force ◽  
Hydraulic Cylinder ◽  
Scientific Basis ◽  
Foundation Settlement ◽  
Empirical Correlations ◽  
Dynamic Reaction ◽  
External Stresses ◽  
Energy Equipment

The N<sub>SPT</sub> index is usually used in empirical correlations to estimate parameters of the soil, carrying capacity, foundation settlement, etc. Because these correlations have no scientific basis, researchers have been developing rational methods of analysis, based on energy concepts. The amounts of energy involved in the SPT test are evaluated by the EFV method. With force and acceleration records, amounts of energy, equipment efficiency, experimental dynamic reaction force of the soil and stresses acting on the sampler were assessed. In this study, a sample extractor system was designed, which consists of a base, a hydraulic cylinder and a load cell. The objective of this equipment is to experimentally quantify the internal friction force, allowing the stresses acting on the sampler to be evaluated. Also, the Aoki's a parameter, which is the ratio of internal friction and external friction between the ground and the sampler, could be calculated.

Radiation-reaction force on a moving mirror

1993 ◽  
Vol 3 (11) ◽  
pp. 2151-2159 ◽  
Author(s):  
Claudia Eberlein
Keyword(s):  
Reaction Force ◽  
Radiation Reaction ◽  
Radiation Reaction Force

Large-aperture deformable mirror correction of tiled-grating wavefront error

2006 ◽  
Vol 133 ◽  
pp. 645-648 ◽  
Author(s):  
B. E. Kruschwitz ◽  
R. Jungquist ◽  
J. Qiao ◽  
S. Abbey ◽  
S. E. Dean ◽  
...  
Keyword(s):  
Deformable Mirror ◽  
Large Aperture ◽  
Wavefront Error
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