multi-robot task allocation are included in the works
of Parker (Parker, 1998), LePape (Le Pape, 1990),
and others (Botelho and Alami, 1999). Mataric
(Gerkey and Mararic) provides a thorough review of
several Multi-Robots Task Allocation Frameworks.
4 AUTONOMOUS RESOURCE
ALLOCATION
Another key attribute of next-generation C2 is
convergence (Alberts, 2007). Convergence is the
ability for independent actors to achieve operational
coherence in a deterministic manner. The emergence
of platforms with multiple modalities (eg. sensing,
SAR, strike, etc….) in the manned and unmanned
arenas allows for additional flexibility in the
allocation of resources at the added cost of an
increasing complexity in the search space. The
resource allocation problem for AC2 must be able to
consider any platform for any task based upon the
platform’s capabilities. Optimizing across any
modality (COMMS, strike, sensing, etc…) is an NP-
hard problem. The AC2 resource allocation must
consider all modalities simultaneously in assigning
assets to objectives.
As stated above, the AC2 resource allocation
problem is a combinatorial optimization problem
that must consider the dynamic environment; a
nonlinear, multi-modal objective function; nonlinear
constraints; and binary decision variables.
Algorithms which address resource allocation
problems of this nature tend to be based on heuristic
methods. The extreme team methods (Scerri et al.,
2005) are effective in the presence of
communications limitations where global decision
support is not a viable option. Extreme teams have
the following characteristic:
• Near real-time assignments
• Platforms may perform more than one task
• Inter-task constraints may be present
Extreme teams are largely based on distributed
constraint optimization problems (DCOP) methods.
These types of algorithms can be applied to either
end of the C2 topology spectrum or can be used in a
complementary fashion for a localized topology
shown in Table 1.
Table 1: Recommended Resource Allocation Algorithms
for C2 Topologies.
The AC2 resource allocation performance must be
considered in light of scalability, satisficing behavior
(GPO, 1982), robustness, and generality. It is
important that the resource algorithm scale for large
numbers of assets and mission objectives. If the
solutions are near-optimal and generated in a
reasonable timeframe, the performance can be
considered to meet the satisficing criteria. In
addition, the algorithm must be stable, converge
rapidly, and insensitive to initial conditions. Finally,
the algorithm must be able to accommodate the
general nature of the objective described above.
The objective function under consideration by the
optimization engine should consider the following
components;
• Mission Effectiveness
• Mission Risk
• Mission Persistence
• Information Utility
The Mission Effectiveness considers all aspects
sensing communications and weapons required to
meet mission goals. The risk component considers
items such as METOC enemy defenses,
deconfliction and energy consumption. The
Persistence parameter may be required to minimize
global change in the solution set. For example, if a
global optimizer is used, then the results could be
dramatically varied at every solution step.
Persistence will reduce this variability. Finally, the
Information component is must be incorporated as a
metric to ensure that the right data gets to the right
place and platforms. For Autonomous C2 the
ramifications of automated subtask generation
should also be considered. Mission planners
generate many subtasks to satisfy the overall mission
objectives to achieve the desired effect(s). AC2 must
also be able generate sub-goals in a parsimonious
manner so that objectives can be accomplished and
new constraints generated by these sub-goals are
readily satisfied. The process of introducing sub-
goals and their associated constraints introduces a
complexity versus performance issue that should be
bounded within the AC2 construct. This notion is
analogous to Akaike’s Information Criterion (AIC)
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