International Core Journal of Engineering 2020-26 | Page 149

of the next target point, which is transferred from point to
point at the moment, is determined based on the cost of the
path and the concentration of the pheromone .
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IN: for the relative importance of pheromones; Relative
importance for heuristics; For the heuristic, The distance to
the point; Time at the moment Pheromone concentration.
With the moment the passage of, side the pheromone
concentration on the rule as shown in the formula (3)
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Indicates time advances to the next iteration, The physical
amount is expressed as the time consumed by the moment plus
the previous iteration; for the evaporation coefficient of the
pheromone, For pheromone residual coefficient, For the
increment of the pheromone, it is calculated by
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Number of ants; For the only ant left on the side in the
search the pheromone concentration on the
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The structure of Tyson polygon shows that every time an
ant selects the next target point at the vertex, it only needs to
choose from the two lines intersecting the vertex, so the
feasible path of Tyson polygon as the initial solution of the ant
colony algorithm will greatly reduce the amount of
computation and improve the efficiency of the algorithm.
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D. Path Optimization and Smoothing
In order to ensure the safe flight of the uavor, each edge is
the furthest from the adjacent threat point in the initial feasible
solution setting but in the actual flight, the drone only needs
to maintain a safe distance from the threat point, so that the
shortest path can be further optimized.
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Eliminate unnecessary vertices in a path as follows: End Is
the initial point, First judge The point ahead The connection
with which it formed Whether to cross the danger zone is
visible in Figure 2 (a),Because The connection is in a safe area,
so further and Point connection, discover To pass through the
danger zone, so sprinkle back Connect and keep Line, move
the initial point to Similarly, connect and check and Path,
connected after confirming that it has not passed the danger
zone Discovery is also in a safe flight zone, so points and
points in the path can be eliminated and directly from the
starting point to the point and then to the end point, and the
optimized path is obtained as shown in Figure 2(b).
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Is a positive constant; For ants In the no. The length of the
path taken in the search for the next iteration.
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Fig1: Initial feasible path based on ants colony algorithm
Based on the safety filtering rules, set the initial value of
pheromone concentration on the remaining edges, so that the
remaining blank area pheromone concentration is 0, so that
ants will only search along the edge of Tyson polygons, thus
limiting the search path and direction of ants The probability
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