Surface error diagnosis of large reflector antenna with microwave holography based on active deformation

2016 ◽  
Vol 52 (1) ◽  
pp. 12-13 ◽  
Author(s):  
Kangkang Liu ◽  
Qian Ye ◽  
Guoxiang Meng
2013 ◽  
Vol 669 ◽  
pp. 283-291
Author(s):  
Fei Wu ◽  
Xiao Jian Chen ◽  
Jia Mei Jin

The piezoelectric ceramic has inverse piezoelectric effect, which can be used in the manufacture of the mold internal compensation-driven. We design a multilayer structure with built-in array of piezoelectric ceramic to achieve active deformation to compensate the tool-shaped face. A piezoelectric micro-displacement compensation model is proposed based on the inverse piezoelectric effect of piezoelectric ceramic. According to the initial face error of tool or from wear, a certain amount of DC voltage is applied on the corresponding area of the piezoelectric ceramic elements to produce certain amount of shrinkage, achieving the goal to adjust tool surface. Based on this theory, we develop a device with active deformation compensation and propose an optimization algorithm of applied voltage.


Author(s):  
Kosuke SHIOKI ◽  
Narumi OKADA ◽  
Toshiro ISHIHARA ◽  
Tetsuya HIROSE ◽  
Nobutaka KUROKI ◽  
...  

GEOMATIKA ◽  
2020 ◽  
Vol 26 (2) ◽  
pp. 107
Author(s):  
Leni Sophia Heliani ◽  
Cecep Pratama ◽  
Parseno Parseno ◽  
Nurrohmat Widjajanti ◽  
Dwi Lestari

<p><em>Sangihe-Moluccas region is the most active seismicity in Indonesia. Between 2015 to 2018 there is four M6 class earthquake occurred close to the Sangihe-Moluccas region. These seismic active regions representing active deformation which is recorded on installed GPS for both campaign and continuous station. However, the origin of those frequent earthquakes has not been well understood especially related to GPS-derived secular motion. Therefore, we intend to estimate the secular motion inside and around Sangihe island. On the other hand, we also evaluate the effect of seismicity on GPS sites. Since our GPS data were conducted on yearly basis, we used an empirical global model of surface displacement due to coseismic activity. We calculate the offset that may be contained in the GPS site during its period</em><em>. </em><em>We remove the offset and estimate again the secular motion using linear least square. Hence, in comparison with the secular motion without considering the seismicity, we observe small change but systematically shifting the motion. We concluded the seismicity in the Molucca sea from 2015 to 2018 systematically change the secular motion around Sangihe Island at the sub-mm level. Finally, we obtained the secular motion toward each other between the east and west side within 1 to 5.5 cm/year displacement. </em></p>


2021 ◽  
Author(s):  
Louis Dufour ◽  
Leri S. Datashvili ◽  
Francois Guinot ◽  
Hervé Legay ◽  
George Goussetis

Sign in / Sign up

Export Citation Format

Share Document