Motion coordination for coverage optimization purposes in mobile networks with limited sensory range is the scope of this paper. The coordination planning is based on Voronoi tessellations by taking into consideration the sensory radius of each agent. Optimization is performed in order to increase the total area covered by the network. An online directional-search algorithm is proposed in order to achieve locally optimal coverage. An agent moves inside its region of responsibility in a way that the total area surveyed by the network increases. The online control action makes the network adaptive to possible changes in the environment. Results are compared to schemes that base their action on Centroidal Voronoi Tessellations (CVT).