Design of a derotator for the 4 in DAG telescope

Baudet, Jeremie
Jolissaint, Laurent
Yerli, Sinan Kaan
This paper Silt our work on the design of a field derotator for the adaptive optics instruments platform of DAG (Dogu Anadolu Cozier vi), a new 4 in telescope for astronomical observations near the city of krzurum, l'urkey. While the telescopefollows an astronomical object, its pupil sees a rotation of the object around the optical axis which depends n the telescope geographic coordinate and the object sky coordinate. This effect is called the field rotation. This rotation needs to be compensated during the astronomical object data acquisition. In this report we demonstrate the feasibility of placing the derotator (a. K-mirror design) in the telescope fork central hole and propose a preliminary design, considering flexures.


Design and development of a complex shear modulus measurement setup for viscoelastic materials
Özgen, Gökhan Osman (2005-01-01)
Details of the design and development study of a complex shear modulus measurement setup for viscoelastic materials have been presented in this paper. The new setup is specifically designed for measuring the complex shear modulus of pressure sensitive adhesives. The setup consists of a rigid block that is connected to a rigid fixture through two identical shear specimens of the viscoelastic material to be tested. The rigid block and the shear specimens resemble a single degree of freedom system. Once the fr...
Cetin, Ramazan; Erturk, Ozan; Akın, Tayfun (2018-09-14)
This study presents design, analysis, optimization, and fabrication of umbrella structures as an efficient quarter wave absorber within the Long Wave Infrared (LWIR) range for uncooled IR detectors. Both the effect of the ni-chrome (NiCr) layer and effect of varying pixel pitch sizes on the IR absorption performance of the umbrella structures are examined. An average of 96% absorption is measured for the optimized case within the LWIR range.
Design of pattern reconfigurable antenna employing RF-MEMS switches
Gök, Çağlar; Alatan, Lale; Department of Electrical and Electronics Engineering (2022-8-17)
In this thesis, the design, simulations, fabrication and measurements of reconfigurable antennas for use in 5G Massive MIMO systems are presented. 26 GHz is chosen as the operating frequency and RF-MEMS switches are used as control elements for pattern reconfiguration. As a first step, a patch antenna is designed based on the excitation of different operation modes of different resonators. A circular patch in the center and a ring resonator structure around it are used to create different radiation patterns...
Direct Reconstruction of Pharmacokinetic-Rate Images of Optical Fluorophores From NIR Measurements
Alacam, Burak; Yazici, Birsen (Institute of Electrical and Electronics Engineers (IEEE), 2009-09-01)
In this paper, we present a new method to form pharmacokinetic-rate images of optical fluorophores directly from near infra-red (NIR) boundary measurements. We first derive a mapping from spatially resolved pharmacokinetic rates to NIR boundary measurements by combining compartmental modeling with a diffusion based NIR photon propagation model. We express this mapping as a state-space equation. Next, we introduce a spatio-temporal prior model for the pharmacokinetic-rate images and combine it with the state...
Development of multiband microstrip antennas for GPS applications
Önder, Mustafa Caner; Aydın Çivi, Hatice Özlem; Department of Electrical and Electronics Engineering (2019)
In this thesis study, the design, fabrication and measurements of dualband and triband circularly polarized microstrip antennas for GPS applications are presented. Characteristic mode analysis technique is applied to get an insight into circularly polarized patch antennas. A design flow is presented for a circularly polarized L1 GPS band microstrip antenna by using characteristic mode analysis. A single fed L1/L2 GPS band right hand circularly polarized four-slotted patch antenna is designed by using reacti...
Citation Formats
J. Baudet, L. Jolissaint, O. KESKİN, C. YEŞİLYAPRAK, and S. K. Yerli, “Design of a derotator for the 4 in DAG telescope,” 2016, vol. 9908, Accessed: 00, 2020. [Online]. Available: