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5<br />

In order to overcome the shortcomings of in literatures<br />

[2] and [3], Xue and Zeng[4] proposed an isotropic<br />

limited-range perceive swarming model that can in<br />

harmony with real biological swarms well, and improve<br />

the coordination motion behavior of multi-agent systems.<br />

0<br />

60<br />

40<br />

-5<br />

5<br />

20<br />

5<br />

0<br />

0<br />

g(y)<br />

0<br />

-5<br />

-5<br />

-20<br />

Figure 2. The paths of the swarm members in Ref. [2]<br />

Chen and Fang[3] proposed an isotropic local perceive<br />

swarming model, the attraction-repulsion functions<br />

considered in this study could avoid collisions, but the<br />

model could not agree well with the nonlinear<br />

characteristics.<br />

-40<br />

-60<br />

-6 -4 -2 0 2 4 6<br />

y<br />

Figure 5. The attraction/repulsion function g(⋅ ) in Ref. [4]<br />

8<br />

6<br />

100<br />

4<br />

80<br />

2<br />

60<br />

0<br />

40<br />

-2<br />

20<br />

-4<br />

0<br />

100<br />

-6<br />

-8<br />

-6 -4 -2 0 2 4 6<br />

50<br />

0<br />

0<br />

20<br />

40<br />

60<br />

80<br />

100<br />

z<br />

Figure 3. The attraction/repulsion function g(⋅ ) in Ref. [3]<br />

100<br />

80<br />

60<br />

40<br />

20<br />

Figure 6. The paths of the swarm members in Ref. [4]<br />

Based on the inspiration from biology, referring to the<br />

known results in literatures [4], we consider a swarm of<br />

M individuals (members) in a n–dimensional Euclidean<br />

space, assume synchronous motion and no time delays,<br />

and model the individuals as points and ignore their<br />

dimensions. The equation of collective motion of<br />

individual i is given by as follows<br />

M<br />

i<br />

i j<br />

( x ) + g( x −x<br />

),<br />

i 1, L M<br />

i<br />

x& = −∇<br />

=<br />

x ∑<br />

i σ , .(1)<br />

j=<br />

1, j≠i<br />

0<br />

100<br />

50<br />

y<br />

0<br />

0<br />

Figure 4. The paths of the swarm members in Ref. [3]<br />

20<br />

40<br />

x<br />

60<br />

80<br />

100<br />

i n<br />

Where x ∈ R represents the position of individual<br />

i ; - ∇ ( x<br />

i )<br />

x<br />

iσ stands for the collective motion’s<br />

direction resting with the different social<br />

attractant/repellent potential fields environment profile<br />

around individual i ; g ( ⋅)<br />

represents the function of<br />

attraction and repulsion between the individuals members.<br />

g ⋅ functions are odd (and therefore<br />

The above ( )<br />

86

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