Characterization of AGV Localization System in Industrial Scenarios Using UWB Technology

Automatic guided vehicles (AGVs) are indispensable elements for the advancement of Industry 4.0 and the digital transformation of factories. These industrial vehicles use embedded intelligence to orient themselves and plan their routes in the short term with the aim of achieving a collaborative, safe, and efficient environment, increasing the competitiveness of industrial plants. However, AGVs still present some challenges that do not allow the full deployment of these vehicles for precision industrial tasks. For this reason, in this article, we propose a localization system to enhance the position determination of AGVs in the industrial plant. This system is based on a wireless ad hoc network that modulates the localization signal through ultra-wideband (UWB) technology to take advantage of the very short duration of the emitted pulses granting robustness against the multipath and non-line-of-sight (NLOS) negative effects typical of industrial environments. In addition, we optimize the location of the architecture sensors through a metaheuristic algorithm (MA-VND-Chains) that requires the definition of the system localization uncertainties given a particular sensor arrangement. For this purpose, we introduce in this article the most complete characterization of the uncertainties of the time difference of arrival (TDOA) localization architecture based on noise, clock, and multipath effects. This allows us to finally obtain localization errors up to six centimeters, thus attaining the required accuracy for AGVs to address high-demanded accuracy applications within the industrial plant.