Metering group is based on precise gear pumps, which are ideal in the application since they allow a variable mixing ratio with a continuous and precise material flow. The continuous flow avoids recharging cycles, ensuring accuracy in the ratio among the different ingredients. Additionally, the gear pumps can deliver a steady large amount of resin, which allows an efficient use of multi-nozzles dispensing heads. The gear pumps size is tailored according to the application and different size pumps can be used, even on the same ingredients, in order to match the most challenging multicomponent recipes. Pumps are managed by fully autonomous drives, which are linked through a closed loop control for precise variable ratio capability, easily controlled by PLC. Gear pumps rotations are interpolated with the robotic dispensing unit movements, to assure regularity of the dispensed resin.