Precision gimballed mirror control in remote sensing LIDAR for environmental monitoring

Ravindra Singh; Ashwani Mudgil; Chandra Prakash; Suranjan Pal

doi:10.1117/12.698001

12 December 2006 Precision gimballed mirror control in remote sensing LIDAR for environmental monitoring

Ravindra Singh, Ashwani Mudgil, Chandra Prakash, Suranjan Pal

Proceedings Volume 6409, Lidar Remote Sensing for Environmental Monitoring VII; 640913 (2006) https://doi.org/10.1117/12.698001
Event: SPIE Asia-Pacific Remote Sensing, 2006, Goa, India

Abstract

Differential Absorption Lidar (DIAL) Systems are advantageously used to detect and measure very small concentrations of trace gases in the atmosphere. There is a requirement to interrogate and search for the presence of one or more of toxic agents out of a large number (about 20 or so) of possible agents at distances up to several kilometers with the help of a ground-based multi-wavelength DIAL system employing pulsed, tunable laser sources in the wavelength bands of 2-5 micron and 9.2-10.8 micron. The Laser beams from the two sources are directed in the atmosphere with a predefined divergence to scan the atmosphere. Two methodologies can be implemented to provide the beam steering, one is to mount the entire telescope of transmitting and receiving channel on to a motorized gimbal platform and second is to keep the optical telescope stationary and use a slewing mirror to steer the beam in required direction. The first scheme is named as mass control and second scheme is called mirror control. Both the schemes have relative advantages and disadvantages and in the present DIAL application second scheme is being adopted. The present opto-mechanical configuration of DIAL system employs a 700 x 500 mm² (Elliptical) steering mirror for transmitting the collimated beams in a required direction and receiving the reflected beam as well. In the receiving channel a Telescope is used which collects the return beam and focuses the same on to a detector. The slewing mirror is housed in a gimbal mount having a sufficient FOR (Field of Regard) in Azimuth and elevation plane. The paper describes the modeling and simulation of Opto-mechanical and servo-mechanical subsystems of precision gimbaled mirror and also discusses the issues related to design of control system. The requirement specifications in regard to field of regard, slew rates 5°/s, scanning rates 1°/s are to be met with stringent beam pointing and scanning accuracies. The design of this system is categorized as multidisciplinary problem. The design parameters obtained from opto-mechanical analysis forms the input for control system design. The design of control system is carried out using conventional design methodologies.

Citation Download Citation

Ravindra Singh, Ashwani Mudgil, Chandra Prakash, and Suranjan Pal "Precision gimballed mirror control in remote sensing LIDAR for environmental monitoring", Proc. SPIE 6409, Lidar Remote Sensing for Environmental Monitoring VII, 640913 (12 December 2006); https://doi.org/10.1117/12.698001

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Mirrors

Control systems design

Sensors

LIDAR

Control systems

Computer aided design

Environmental monitoring

Show All Keywords

Keywords/Phrases

Search In:

Publication Years