DIRECTED ENERGY PROFESSIONAL SOCIETY


Beam Control Conference 2011
Short Courses

23 May 2011 Orlando, Florida

These short courses were offered in conjunction with the Beam Control Conference, held in Orlando, Florida on 23-26 May 2011. Continuing Education Unit (CEU) credits were awarded for completion of these DEPS short courses.


Morning Course: Course 1: Beam Control System of the Airborne Laser Test Bed (Limited)

Afternoon Course: Course 2: WaveProp Tutorial (Open)

Full Day Course: Course 3: Introduction to Beam Control (Open)


Course 1.  The How and Why of the Beam Control System of the Airborne Laser Test Bed

Classification: Unclassified, Limited Distribution D, ITAR (U.S. Only)

Course Level: Intermediate

Instructor: Kenneth Billman, Lockheed Martin

Duration: Half-day course, starts at 0800

CEUs awarded: 0.35

Course Description: On 11 February 2010 the Missile Defense Agency demonstrated the potential use of directed energy against ballistic missiles when the Airborne Laser Test Bed (ALTB) system successfully destroyed a distant, fast moving, threat-representative boosting ballistic missile. The ALTB is a pathfinder for the nation’s directed energy (DE) program, designed to demonstrate the essential technologies for future DE systems. This demonstration showed the excellent performance of what DE experts believed to be the most challenging segment of the system, the Beam Control System (BCS). In this course we will answer the many questions about the design choices of the BCS. Starting with its allocated requirements, we will follow the many design trade studies that decided its common path / common mode architecture for both pointing and wavefront compensation, its choice of active tracking, its unique use of a vertical optical bench, of multiple beamlet target illumination, of helium beam path gas, of special sensors, inertial pointing, and many more innovations that convinced us that the design could be sufficiently robust to successfully send a MW-class laser beam from a non-rigid airframe through atmospheric turbulence to a distant, km/s small cross section moving target, while keeping the tightly focused laser beams on target until kill. Finally, we will discuss those features that performed exceptionally well and others that should be considered for improvement with more modern technology. Since this BCS has been emulated by many more recent systems, it is important that those working DE systems, understand the ALTB BCS design, capabilities and limits.

Intended Audience: Students will be presented with the system engineering process that was followed to proceed from system level requirements to the final design and its test in a scaled laboratory facility. An undergraduate background in optics, lasers, controls, and modern math will be helpful. Both managers and researchers will find this course informative. It is believed that, consistent with time and security, an interactive exchange is possible.

Instructor Biography: Dr. Billman has extensive experience in advanced technology development, especially in lasers, adaptive optics, and directed energy systems. He designed and built his first laser in 1967 at the NASA Electronics Research Laboratory. During the ‘70’s he led the NASA high power laser effort as Chief, Laser Branch, NASA Ames Research Center. During the early 80’s he managed the laser and ion fusion programs at the Electric Power Research Institute, and during the late 80’s he managed the San Francisco Bay Area Photonics Office of TITAN Systems. In 1989 he joined Lockheed, later Lockheed Martin (LM), as it’s Chief Scientist on the SDIO’s Ground-Based Free Electron Laser program. Following this he managed the SDIO Neutral Particle Beam program. In mid-1994 he became the Program Manager of the 30-month Lockheed effort to design the beam control/fire control segment of the Airborne Laser Program. Following the Government award of the follow-on program to engineer, develop, and test this design, in partnership with Boeing and TRW’s efforts on their segments, he served as the Integrated Product Team Lead and Chief Scientist on the LM ABL PDRR program.


Course 2.  WaveProp Tutorial

Classification: Unclassified, Public Release

Course Level: Intermediate

Instructor: Terry J. Brennan, the Optical Sciences Company

Duration: Half-day course, starts at 1300

CEUs awarded: 0.35

Course Description: The capability to perform reliable wave optics simulation has become almost essential for developing directed energy laser applications. This is particularly true for high energy systems which operate in strong atmospheric turbulence conditions where effects such as saturation of scintillation, branch points in the phase, and thermal blooming are important. For these effects analytic techniques are generally not available and it becomes necessary to perform numerical simulations of electromagnetic wave propagation. Developing high fidelity simulations that include detailed hardware models such as wavefront sensors is a daunting task for most researchers and engineers. An alternative is to use one of the available simulation packages.

This course is a tutorial on the use of WaveProp, an object-oriented wave optics simulation system developed entirely in Matlab. WaveProp has been developed over the last ten years by the Optical Sciences Company as a tool to assist in basic propagation research as well as evaluation of optical system performance. It has been used effectively on many programs and for a wide range of applications including laser weapons, laser communications, and imaging. It can be used to gain quick insight into a propagation problem or to model highly detailed systems such as the ABL and the AGS (Automated Ground System). Outside of tOSC it is available to government researchers and their contractors and has been used by researchers at AFRL, AFIT, the Navy and The Aerospace Corporation with a significant number of users at the Starfire Optical Range

The course will describe WaveProp’s approach for modeling:

  • Sources (point sources, extended sources)
  • Propagation through turbulence (including inner scale)
  • Thermal blooming
  • Sensing devices (Hartmann Sensors, SRI sensors)
  • Corrective devices (deformable mirrors, steering mirrors)
  • Segmented optics, phased arrays
In addition to reviewing WaveProp’s extensive set of classes the course will describe tools for designing adaptive optics systems and adding new classes (models). The first half of the course will consist of a discussion of the underlying principles and usage of WaveProp. During the second half a range of simulation examples will be demonstrated live with opportunities for students to interact with the demonstrations. Although not required, students who would like to bring a laptop computer to the course may install a copy of WaveProp for following along with the demonstrations. The student’s computer must already have Matlab installed.

Intended Audience: This course is for scientists and engineers interested in modeling and simulating optical propagation through turbulence. Some knowledge of propagation theory and modeling techniques will be assumed as well as a working knowledge of Matlab.

Instructor Biography: Dr. Terry Brennan is a Senior Scientist at the Optical Sciences Company (tOSC) where he has worked for the last 20 years. Prior to working at tOSC he managed the Space Structures Control Section at The Aerospace Corporation. He is the principle architect of WaveProp and he has been active in analysis, simulation, experiment design, and data analysis on a wide range of programs in the area of adaptive optics. Dr. Brennan has made numerous contributions to the ABL program including identification and characterization of speckle effects in the atmospheric compensation loop and introduction of reconstructor techniques to restore phase margin lost due to misregistration. In support of lasercom programs, Dr. Brennan developed the AGS woofer/tweeter control design for mitigation of branch cut fitting error on continuous surface DMs. He has also developed techniques for estimating r0, the Greenwood frequency, and inner scale of turbulence and led the development and delivery to SOR of a mobile sensing system which incorporates these techniques. Dr. Brennan received his Ph.D. in mathematics at the University of California in Irvine.


Course 3.  Introduction to Beam Control

Classification: Unclassified, Public Release

Course Level: Intermediate

Instructor: Paul Merritt, University of New Mexico

Duration: Full-day course, starts at 0800

CEUs awarded: 0.70

Course Description: The course is an overview of the technology and analysis needed to understand and design the beam control systems that accomplish acquisition, pointing, and tracking for a laser system. The system could be communications, imaging, or laser deposition, and the technology would still be very similar. The course also includes introductory lectures on control theory, as well as the performance equations that describe propagation of a laser beam to target. The attendees will be given the basic equations necessary to describe beam control system performance. The course will also include an introduction to adaptive optics beam control systems and a look at future beam control systems for fiber optics. Topics to be covered include:

  • System performance equations
  • Beam control hardware
  • Controls basics
  • Gimbals
  • Tracking
  • Adaptive optics control
  • Fiber optics beam control

Intended Audience: The students will obtain an overall understanding of the analysis needed to describe, design, and evaluate a beam control system. The course assumes that the attendee has a basic undergraduate level of engineering and mathematics. The solution of differential equations is used to describe the operation of control systems. Both technical persons and managers should benefit from the development and discussions regarding the operation of beam control systems. Technicians may find the course too analytical. The author has included references at the end of each section such that a student in the area may delve much deeper into the material if desired. No experience in the field is required; however, some experience will be helpful since the topics are covered rapidly.

Instructor Biography: Dr. Merritt started working on laser systems in 1974 on the Airborne Laser Laboratory. Also in 1974, he received his Ph.D. in Mechanical Engineering from the University of New Mexico. He worked in civil service for several of the Kirtland laser organizations including the Weapons Laboratory, Phillips Laboratory, and Air Force Research Laboratory. His last civil service assignment was the Technical Advisor for the Airborne Laser Technology Division. He retired from the government in 1997 and went to work for Boeing-SVS in Albuquerque where he continued to analyze beam control systems. He was a Boeing Senior Technical Fellow. He retired from Boeing in 2003 and is now working for the University of New Mexico. He is teaching a controls class at the University and is a part time consultant with RDTA at the Air Force Research Lab.

 
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Last updated: 28 June 2011