The company Bosch is developing a farming robot the size of a small car that can distinguish crops from weeds by looking at the shape of leaves, and this robot then can fish out weeds mechanically & ram any unwanted plants into the ground with a rod. Potentially, no herbicides will be needed in the future! Take that Monsanto!
Finally some good news on the robot front!
Source: Bosch Bonirob robot set to make field work easier for farmers – Farmers Weekly