🚀 go-pugleaf

Selected papers are now available via anonymous ftp regarding
the Naval Postgraduate School Autonomous Underwater Vehicle.
Additional references are available upon request.

Currrent:  

aaai92ws.ps  "From virtual world to reality: designing an autonomous
             underwater robot" by Don Brutzman
             AAAI Fall 92 Symposium:  Applications of Artificial
             Intelligence for Autonomous Mobile Robots, 23-25 OCT 92

oceans92.ps  "Autonomous Sonar Classification using Expert Systems"
             Don Brutzman, Mark Compton, Yutaka Kanayama
             Proceedings of IEEE Oceans Engineering Society Conference
             OCEANS 92, 26-29 OCT 92

auv92.ps     "NPS AUV Integrated Simulator"
             Don Brutzman, Yutaka Kanayama and Michael Zyda
             Proceedings of IEEE Oceans Engineering Society Conference
             AUTONOMOUS UNDERWATER VEHICLES 92, 3-4 JUN 92


To obtain a copy of compressed postscript papers:

ftp ftp.cs.nps.navy.mil
login:  anonymous
password:  youraccountname@site.domain

ftp> cd pub
ftp> cd auv
ftp> ls

You will now see what is available.  To get a paper:
ftp> get auv92.ps.Z
ftp> quit

Back on your unix system you must uncompress the postscript file
   prior to printing:
unix> uncompress auv92.ps.Z
unix> lpr auv92.ps

comments or questions:  e-mail is welcome.

regards, Don            brutzman@cs.nps.navy.mil


Abstracts follow.
___________________________________________________________________

           From virtual world to reality:
      designing an autonomous underwater robot

Design of autonomous underwater robots is particularly
difficult due to the physical and sensor challenges of
the underwater environment.  Inaccessibility during
operation and low probability of failure recovery makes
robot stability and reliability paramount.  Building an
accurate and complete virtual world simulation is
proposed as a necessary prerequisite for design of an
autonomous underwater robot.  A virtual world can
include actual robot components and models for all
other aspects of the world.  Robot design can be fully
tested using a virtual world and then verified using the
real world.  Additional testing can be performed in the
virtual world that is not feasible in the real world.
Visualization of robot interactions within a virtual world
permits sophisticated analysis of robot performance that
is otherwise unavailable.  All aspects of world modeling
and robot design must be mastered and coordinated in
order to build an authentic virtual world and capable
autonomous robot.

------------------------------------------------------------

  AUTONOMOUS SONAR CLASSIFICATION USING EXPERT SYSTEMS

Abstract - An expert system can process active sonar returns,
perform geometric analysis and autonomously classify detected
underwater objects.  Autonomous classification of objects is an
essential requirement for independent operation by autonomous
underwater vehicles (AUVs).  Most AUVs are only capable of
rudimentary sensor analysis, since standard approaches to
evaluation and classification of sonar data require excessive
signal processing and computational power to be practical.  This
paper describes how to develop an autonomous sonar
classification expert system for a working AUV.
         A fundamental approach is presented for applying geometric
reasoning and expert system heuristics to sonar classification.
Preliminary sonar processing is performed using parametric
regression line fitting.  A polyhedron-building algorithm
correlates the parametric regression line segments into geometric
objects.  After quantifying geometric object attributes, objects
are classified using rule-based evaluation of quantitative and
qualitative attributes combined with sonar classification
heuristics.
         A summary of expert systems describes their salient features
pertinent to autonomous sonar classification systems.  The expert
system paradigm, knowledge representation, reasoning using
facts and rules, rule sets, control of execution flow and expert
system development are outlined.  Expert system self-diagnosis
and self-correction are also discussed.
         Implementation was performed using the "C" Language
Integrated Production System (CLIPS) expert system shell.
Real-time graphic simulation and scientific visualization are
employed to evaluate results.  Experimental sonar classification
results are presented using actual mission data from the Naval
Postgraduate School (NPS) AUV.  Successful classifications of
walls and a mine-like object are demonstrated.

---------------------------------------------------------------

      INTEGRATED SIMULATION FOR RAPID DEVELOPMENT OF
             AUTONOMOUS UNDERWATER VEHICLES

The development and testing of Autonomous Underwater Vehicle
(AUV) hardware and software is greatly complicated by vehicle
inaccessibility during operation.  Integrated simulation remotely
links vehicle components and support equipment with graphics
simulation workstations, allowing complete real-time, pre-mission,
pseudo-mission and post-mission visualization and analysis in the
lab environment.  Integrated simulator testing of AUV software
and hardware is a broad and versatile method that supports rapid
diagnosis and robust correction of system faults.
            Pre-mission simulator AUV testing permits experimental
evaluation of developmental software.  Pseudo-mission simulator
testing of AUV processes employs an identical laboratory
microprocessor or remote communication with a
testbench-mounted operating AUV, permitting end-to-end testing
of all software and hardware.  Post-mission simulator playback of
recorded telemetry, sensor data and system state transitions
supports in-depth reenactment, playback and analysis of in-water
operational results.
            High-resolution three-dimensional graphics workstations
can provide real-time representations of vehicle dynamics, control
system behavior, mission execution, sonar processing and object
classification.  Use of well-defined, user-readable mission log files
as the data transfer mechanism allows consistent and repeatable
simulation of all AUV operations.  Examples of integrated
simulation are provided using the Naval Postgraduate School
(NPS) AUV, an eight foot, 387-pound untethered robot submarine
designed for research in adaptive control, mission planning,
mission execution, and post-mission data analysis.
            The flexibility, connectivity and versatility provided by
this approach enables sophisticated visualization and analysis of
all aspects of AUV development.  Integrated simulator networking
is recommended as a fundamental requirement for comprehensive
and rapid AUV research and development.