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Control >> Finding object/goal >> Goal search

Goal search

In this section, we present a second series of experiments, in which a group of ten s-bots has to find a goal item-the prey-placed at varying distances from the nest.

Similar to the task of the previously presented experiment, the s-bots have to explore the environment by forming chains. The difference is that a goal object is added to the environment. When the goal is encountered by a chain, a connection has to be established, in this way forming a path that connects nest and goal, and that allows other s-bots to navigate between the two locations.

Experimental setup

We use the same controller as in the previous section.

Results

Figure 1 shows the success rates for the three strategies for finding and connecting to a prey object which is placed at two different distances from the nest. We define an experiment to be successful if the group of s-bots is able to locate the prey object within 1000 s.

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Figure 1. The success rates for the static (top row), the aligning (centre row), and the moving strategy (bottom row), when the prey is placed at a distance of 180 cm (left column) or 270 cm (right column).

The moving strategy in general performs better than the other ones because robots aggregated into a chain contribute to the exploration process by collectively moving around the nest. In opposition to the other two strategies, a lower probability to disaggregate from a chain results in a higher success rate because low values of P(chain->expl) decrease the frequency of situations in which a chain may not move, in this way increasing the time during which a chain can explore the environment. The most successful values of the probability to aggregate into a chain are in the range [0.005,0.01]. Higher values lead to the formation of more than one chain, and lower values, while leading to a single chain, result in a slower chain formation process.


References



Control >> Finding object/goal >> Goal search

Swarm-bots project started
on October 1,2001
The project terminated
on March 31, 2005.
Last modified:
Fri, 27 Jun 2014 11:26:47 +0200
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