2013 LIDAR'S TELESCOPE AUTO-ALIGNMENT SYSTEM FOR CTA Auteurs principaux : Mr. PALLOTTA, Juan Co-auteurs : Dr. RISTORI, Pablo 1 ; Dr. OTERO, Lidia 1 ; Mr. CHOUZA,Fernando 1 ; Mr. D'ELIA, Raul 1 ; Dr. ETCHEGOYEN, Alberto 2 ; Dr. QUEL, Eduardo 1 Intervenant : Dr. RISTORI, Pablo 1 on behalf of Mr. PALLOTTA, Juan 1.- CEILAP (CITEDEF-CONICET), UMI-IFAECI-CNRS (3351) 2.- ITeDA (CNEA-CONICET-UNSAM) 1

2013 Outlook 2 -Multiwavelength Scanning Raman Lidar. Main features. -New shelter-dome to host the lidar. -Remote Operation System: Principles -Auto-alignment Procedure: the hardware -Auto-alignment Procedure: the software -Auto-alignment Procedure: examples -Others: Spectrometric Box -Others: Scanning Structure -Others: Telescope Improvements -Conclusions

2013 Argentine Multi-angle Raman Lidar Main Features:  Emission:  Nd:Yag laser Inlite II-50 from Continuum. Energy per pulse 532nm.  Reception Optics:  6 reception mirrors:  Ø = 40cm  F=1m. With optical fiber Ø = 1 mm at its focus.  Detection lines: 3 elastic and 3 Raman.  Elastic: 355, 532 and 1064 nm  Raman: 387, 408 and 607 nm 3 3

2013 Shelter-Dome  Based on the idea of CLUE shelter, built from a standard 20 ft. shelter modified completely as is shown in the figures.  For open/close the shelter, hydraulic cylinders were installed and can be controlled manualy on site or remotely via WiFi.

2013 Remote Operation System 5  The whole multiangle lidar is controlled remotely via WiFi link between the control PC and the lidar shelter.  Data-taking procedure highly automated.

2013 Auto-alignment Mirror System. Hardware 6

2013 Auto-alignment Mirror System. Hardware 7

2013 Auto-alignment Mirror System. Algorithm(1)  Auto-alignment system procedure is based on tilting the telescope, acquiring lidar signal, and quantifying the overlap factor.  Due to the fact that overlap factor modulates the lidar function, alignment condition can be assured by evaluating the signal through a certain range. The best overlap will be attained when the signal reaches its maximum value over this range 8

2013  Alignment is performed evaluating the mean of the lidar signal over a certain range. Auto-alignment Mirror System. Algorithm(2) 9

2013 Auto-alignment Mirror System. Algorithm(3)  The tilt angle of the telescopes is driven by a set of stepper motors, handled by a RCM2200 Rabbit System microcontroller. It has a built-in Ethernet interface with an integrated TCP/IP stack. This interface is used to link the Multiangle Raman lidar with the control lidar PC.  The telescopes are controlled by a self- alignment system, which is a cooperative procedure performed by PC software running from the acquisition module and connected via WiFi to a microcontroller.

2013 Alignment vs. Simulation 11

2013 Alignment under different weather conditions 12

2013 Auto-alignment Mirror System. Algorithm(3) 13

2013 Spectrometric box  Detection lines: 3 elastic and 3 Raman.  Elastic: 355, 532 and 1064 nm  Raman:  Nitrogen: 387 and 607 nm (from 355 and 532).  Water vapor: 408 nm (from 355 nm).  Planned to be manufactured in collaboration of the Advanced Modeling Laboratory at CITEDEF with a sintering machine. This will improve deployment time, reduce the size, weight of the whole detection system. 14

2013 Spectrometric box  Detection lines: 3 elastic and 3 Raman.  Elastic: 355, 532 and 1064 nm  Raman:  Nitrogen: 387 and 607 nm (from 355 and 532).  Water vapor: 408 nm (from 355 nm).  Planned to be manufactured in collaboration of the Advanced Modeling Laboratory at CITEDEF with a sintering machine. This will improve deployment time, reduce the size, weight of the whole detection system. 15 Same optics being used at Comodoro Rivadavia’s Lidar

2013 New azimuth-zenithal scannign bench  System being build with Mechanical Department of CITEDEF.  Already tested, highly rouged and stable.  Max. azimuth/zenithal velocity: 5 rpm.  Max. azimuth/zenithal aceleration: 1,7 rad/s 2 16

2013 New azimuth-zenithal scannign bench  System being build with Mechanical Department of CITEDEF.  Already tested, highly rouged and stable.  Max. azimuth/zenithal velocity: 5 rpm.  Max. azimuth/zenithal aceleration: 1,7 rad/s 2 17 Same unit operational at CITEDEF

2013 Telescope technology intercomparison 18

2013 Telescope technology intercomparison 19

2013 Summary 20  Argentinean multiangle Raman lidar is already hosted in its shelter-dome and can be operated remotely via WiFi.  Lidar signals were taken with only one telescope. The rest of them rest to be installed in near future.  Rest to implement the new scanning bench and program the scanning software.  The data acquisition software is already operational, and few features left to be done.