Source strength

The gas concentration profile is obtained by assuming the odor source to emit odor patches which are transported by wind and turbulence. By reducing the number of patches emitted by the source, the performance of the algorithm in dilute conditions is analyzed. A reduction in source strength results in a lesser probability of encountering a patch by a glowworm.

The algorithm is seen to converge successfully even under dilute conditions (see Figure (a)). In Figure (b) the glowworm trajectory for a source strength N = 2 patches per sec can be seen. Initially, a glowworm close to the x-axis acquires the highest luciferin value and attracts other glowworms toward it. This glowworm then moves upwind since it is in the anemotactic mode. As the frequency of arrival of patches is less, the upwind motion of the glowworm is delayed. This results in delayed convergence.

Figure: (a) Algorithm performance with variation in source strength. (b) Glowworm trajectory with source strength, N=2.