Path Planning and Collision Risk Management Strategy for Multi-UAV Systems in 3D Environments

. 2021 Jun 28;21(13):4414. doi: 10.3390/s21134414

Algorithm 1 Routine of the complete developed strategy

1:
$W o$ ← Occupation matrix of the simulated environment
2:
$W_a r r a y$ ← Viscosity maps computed from $W o$ . Constraints: Distance to obstacles and flight levels.
3:
Define number of drones
4:
Define the position of the two depots
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Depot assignment: Half of drones to one depot and the other half to the other
6:
$i t e r a t i o n_i n d e x$ ← 0
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while $i i t e r a t i o n_i n d e x$ < 7000 do
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$d e p o t_q u e u e s$ ← Queues of drones waiting to take off in depots
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for every $d r o n e$ do
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if drone ends its current mission or $i t e r a t i o n_i n d e x$ == 0 then
11:
$d r o n e . p a t h$ ←Generate_mission( $d r o n e . p o s i t i o n$ , $d r o n e . d e p o t_p o s i t i o n$ , $W_a r r a y$ )
12:
$d r o n e . v e l o c i t y$ ← 0
13:
end if
14:
if drone is waiting to start new mission then
15:
$d r o n e . v e l o c i t y$ ←Take_off_distance_check( $d r o n e . I D$ , $d e p o t_q u e u e s$ )
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end if
17:
for every $d r o n e_o f_h i g h e r_I D$ do
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( $v 1$ , $v 2$ ) ←Check_conflicts( $d r o n e$ , $d r o n e_o f_h i g h e r_I D$ )
19:
$d r o n e . v e l o c i t y$ ← $v 1$
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$d r o n e_o f_h i g h e r_I D . v e l o c i t y$ ← $v 2$
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end for
22:
if drone without conflicts being the non_priority vehicle and not landed then
23:
$d r o n e . v e l o c i t y$ ← 1
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end if
25:
end for
26:
$i t e r a t i o n_i n d e x$ ← $i t e r a t i o n_i n d e x$ + 1
27:
end while