Environmental Engineering Reference
In-Depth Information
New Millennium Program (NMP)
The New Millennium Program (NMP) is a NASA/Jet Propulsion Laboratory
(JPL) project that will aggressively demonstrate new technologies for automa-
tion and autonomy. Though the primary thrust is technology, the project has
scientific goals. NMP will fly a series of deep space and earth-orbiting space-
craft, the first of which was launched in 1998. Some of the software technologies
are:
Model-based reasoning
Planning and scheduling architectures
Executive architecture (performs plans)
Fuzzy logic
Neural networks
The DS1 spacecraft, launched in 1998, was the first to employ an on-board,
autonomous system, AutoNav, to navigate to celestial bodies. About once
per week throughout the mission, AutoNav was invoked [ 114 ]. The system
made navigation decisions about spacecraft trajectory and targeting of celes-
tial bodies with little assistance from ground controllers.
DS1 also used the New Millennium Remote Agent (NMRA) control archi-
tecture (Fig. 7.15 ) [ 100 ]. In two separate experiments, the remote agent was
given control of the DS1 spacecraft. The remote agent involved an on-board
mission manager that used a mission plan comprising high-level goals. A plan-
ning and scheduling engine generated a set of activities based on the goals, the
spacecraft state, and constraints on spacecraft operations. The plan execution
component incorporated a hybrid reactive planner and a model-based iden-
tification and reconfiguration system. The reactive planner decomposed the
activities supplied by the high level planner into primitive activities, which
were then executed. The model-based reasoning component used data from
sensors to determine the current mode from the current spacecraft state. If
a task failed, the model-based component assisted the reactive planner by
using its model to act as a recovery expert and determine possible recovery
strategies.
Remote Agent
Ground
System
Mission
Manager
Mode ID
&Reconfig
Real-Time
Executive
Planner/
Scheduler
Smart
Executive
Flight
H/W
Monitors
Planning Experts
(incl. Navigation)
 
 
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