Page 71 - Innovations in Intelligent Machines

60 P.B. Sujit et al.
50
ρ=1.77
ρ=0.886
45
40 ρ=0.443
Number of targets destroyed 30 ρ=0.266
35

25

20
15

10 Negotiation only
Negotiation with
information exchange
5
0
0 50 100 150 200 250 300 350 400
Time steps

Fig. 7. Number of targets destroyed for different proximity factors

schemes. From the figure we can see that for lower proximity factors the
number of targets destroyed are low as compared to the number of targets
destroyed in the higher proximity factor case. When the proximity factor is
small, the effect of target information sharing during decision-making by the
agents that have targets in their sensor range is significant. For ρ =0.266,
we can see from the figure that the performance of negotiation with target
information based task allocation is better than that using negotiation only.
Here, the target information broadcast plays a crucial role in enhancing the
performance. Similar kind of effect can be seen for ρ =0.443. However, for
σ =0.886, the negotiation based task allocation is better than that with
target information exchange. This is due to the fact that the additional infor-
mation about distant targets makes the agent choose distant targets to attack
rather than perform search in its own neighborhood. This causes UAVs to
miss nearer targets outside its sensor range. For ρ =1.77, the performance is
the same for both the negotiation schemes. Since the proximity factor is high,
all the agents can sense all the targets hence there is no improvement in per-
formance with information exchange. It should be noted that the amount of
information broadcast also plays a crucial role in the performance of the task
allocation. Hence, there is always a tradeoff between how much of information
should be broadcast and the performance.