For decreasing the environmental impact of agricultural activities, while preserving the level of production to satisfy growing population demands, autonomous devices, like mobile robots, with middle sizes, working together in a fleet and supervised by an operator and equipped with several sensors, may constitute a promising solution, to realize agricultural tasks, instead of using big machines. They present the advantages of high ability of modularity and permit to increase production level, while reducing pollution thanks to a high accuracy and repeatability. The quality of both communication and localization sensors used must be high, for these fleet operations, to realize, correctly, with safety, these tasks. To control the fleet of vehicles, some laws are used, which take into account the vehicle mechanical parameters, the environement data and the data acquired by sensors.