This paper introduces gyroscopic forces as an tool that can be used in addition to the use of potential forces in the study of collision and convex obstacle avoidance. It makes use of the concepts of a detection shell and a safety shell and shows, in an appropriate context, that collisions are avoided, while at the same time guaranteeing that control objectives determined by a potential functio...

A cellular automaton model is presented for random walkers with biologically motivated interactions favoring local alignment and leading to collective motion or swarming behavior. The degree of alignment is controlled by a sensitivity parameter, and a dynamical phase transition exhibiting spontaneous breaking of rotational symmetry occurs at a critical parameter value. The model is analyzed usi...

Bacillus subtilis swarms rapidly over the surface of a synthetic medium creating remarkable hyperbranched dendritic communities. Models to reproduce such effects have been proposed under the form of parabolic Partial Differential Equations representing the dynamics of the active cells (both motile and multiplying), the passive cells (non-motile and non-growing) and nutrient concentration. We te...

Abstract Microswimmers exhibit an intriguing, highly-dynamic collective motion with large-scale swirling and streaming patterns, denoted as active turbulence – reminiscent of classical high-Reynolds-number hydrodynamic turbulence. Various experimental, numerical, theoretical approaches have been applied to elucidate similarities differences inertial We use squirmers embedded in a mesoscale flui...

The motilities of Proteus long forms during swarming on agar were measured on cells transferred to liquid suspension. During concentric-ring formation on solid medium, when the edge of the swarm was advancing slowly or had stopped, the velocity of long-form motility was low. When the colony was spreading rapidly, long-form velocitywas relatively high. This periodic variation in cell velocity, w...