2013

LIDAR'S TELESCOPEAUTO-ALIGNMENT SYSTEM FOR

CTAAuteurs principaux : Mr. PALLOTTA, Juan

Co-auteurs : Dr. RISTORI, Pablo1; Dr. OTERO, Lidia1; Mr. CHOUZA,Fernando1; Mr. D'ELIA, Raul1; Dr. ETCHEGOYEN, Alberto2; Dr.

QUEL, Eduardo1

Intervenant : Dr. RISTORI, Pablo1 on behalf of Mr. PALLOTTA, Juan

1.- CEILAP (CITEDEF-CONICET), UMI-IFAECI-CNRS (3351)2.- ITeDA (CNEA-CONICET-UNSAM)

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2013

Outlook

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- 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

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Argentine Multi-angle Raman Lidar

Main Features:

Emission: Nd:Yag laser Inlite II-50 from

Continuum. Energy per pulse 60mJ @ 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

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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.

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Remote Operation System

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The whole multiangle lidar is controlled remotely via WiFi link between the control PC and the lidar shelter.

Data-taking procedure highly automated.

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Auto-alignment Mirror System. Hardware

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Auto-alignment Mirror System. Hardware

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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)

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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.

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Alignment vs. Simulation

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2013

Alignment under different weather conditions

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Auto-alignment Mirror System. Algorithm(3)

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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.

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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.

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Same o

ptics b

eing u

sed

at Com

odoro R

ivadavia’s Lid

ar

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/s2

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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/s2

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Same u

nit opera

tional a

t CIT

EDEF

2013

Telescope technology intercomparison

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Telescope technology intercomparison

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2013

Summary

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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.