Meet the Oz Weeding Robot: another agricultural robot that helps during weeding and hoeing chores to reduce your daily workload. It is autonomous but can be guided to go where you want. When in follow mode, Oz follows your steps and tows your trailer.
The robot has 4 x 110w electric engines. Just tell it how many rows it needs to weed, how long they are, and how far apart, and the robot takes care of the rest. The specs are available here.