May 17, 1999
 
COMPUTER PROGRAM ASSUMES SPACECRAFT COMMAND 
 
    It's one small step in the history of robotic space flight; but it may turn 
out to be one giant leap for computer-kind:  Artificial intelligence software is 
in primary command of a spacecraft for the first time.  
 
    Known as Remote Agent, the software has been operating NASA's Deep Space 1 
mission and its futuristic ion engine since 11 a.m. Pacific Daylight Time today, 
May 17.  The question: Can a spacecraft function entirely on its own nearly 120 
million kilometers (75 million miles) from Earth, without detailed instructions 
from the ground?  
 
    The public is invited to follow this ambitious 48-hour test as it continues 
to unfold today and tomorrow, through a detailed web page and e-mail alerts 
triggered by actual events on Deep Space 1.  Learn more or sign up online at 
http://rax.arc.nasa.gov .
 
    "While we watch over its shoulder electronically, we are giving Remote Agent
the responsibility to monitor Deep Space 1's activities and position in space,
including any engine firings it needs to keep on course," said Dr. Pandu Nayak,
deputy manager of Remote Agent development at NASA's Ames Research Center,
Moffett Field, CA.  "We are also challenging Remote Agent with some 'unexpected
problems' to see how well it reacts, and to determine whether it can get the 
mission back on track without human intervention."
 
    "Remote Agent can create and carry out its own plans to achieve the mission 
goals that we give it," said Dr. Doug Bernard, Remote Agent manager at NASA's Jet 
Propulsion Laboratory, Pasadena, CA.  "This technology could allow us to pursue 
solar system exploration missions that only a few years ago would have been 
considered too elaborate, too costly or excessively dependent on teams of 
Earth-bound controllers." 
 
    The Remote Agent software package features three components:  the
Planner/Scheduler, the Executive and one called Livingstone.  
 
    The Planner takes general goals and determines detailed activities needed to 
achieve the goals.  The test includes asking the Planner to achieve broad goals 
such as, "Find your position, and fire your ion engine whenever practical."  If a 
hardware problem develops that prevents execution of the plan, the Planner makes 
a new plan, taking into account degraded capabilities.  
 
    The Executive interprets the plans and adds more detail to them, then issues
commands to the flight software, coordinating the three parts of Remote Agent. 
Some commands turn the spacecraft to point in a different direction.  Other 
commands ask the onboard camera to take pictures of asteroids and stars for 
navigation purposes.
 
    Livingstone acts like a doctor, monitoring the spacecraft's health.  If 
something goes wrong, Livingstone tells the Executive there is a problem.  The 
Executive consults the "doctor" for simple procedures that may quickly remedy the 
problem.  For example, if the camera does not respond, a quick fix is to turn the 
camera off and then on again.  If this does not work, the Executive asks the 
Planner for a new plan that still achieves mission goals.  If the problem is too 
serious, the software gives up and waits for help from Earth.
 
    Specific tests include simulation of hardware problems, such as a
malfunctioning spacecraft thruster.  This should prompt the software to diagnose
the cause of the apparent problem and take corrective action.  Remote Agent is
designed to detect and recover from a set of real subsystem failures in the 
unlikely event that an actual failure should occur on Deep Space 1 during the 
remainder of the experiment.
 
    Launched October 24, 1998, Deep Space 1 is validating 12 new technologies,
including Remote Agent, so that they can be confidently used on science missions 
of the 21st century.  Its ion propulsion system has now completed more than 73 
days of thrusting, most of that time under the control of the spacecraft's 
autonomous navigation system.  The Deep Space 1 team expects that testing of all 
technologies will be complete by early June, with the exception of navigation 
system tests scheduled during an encounter with asteroid 1992 KD in late July. 


Contact:  John G. Watson, JPL, (818) 354-5011
John Bluck, NASA Ames Research Center, (650) 604-5026


MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109.  TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov