Scientists from the University of Córdoba developed a unique vehicle to automate agricultural tasks, contributing to the Automation 4.0 movement. This project involved collaboration with two companies responsible for the vehicle's mechanical manufacturing and programming. The initiative highlights integrating advanced technology in agriculture to enhance efficiency and productivity. The study was published in the journal Computers and Electronics in Agriculture.
The team of the University of Cordoba. Image Credit: University of Cordoba
The name Sergius may mean “one who serves,” which is why the robotic tractor that can carry out agricultural duties in woody crop fields is called that.
On the national market, there are some small autonomous vehicles that can be applied to agriculture, but there were none with a tractor's functionality. This vehicle has the same functions as a tractor, but is groundbreaking in that, in addition to being autonomous, it features two independent self-leveling axles with steerable wheels, which makes its control more versatile.
Rubén Sola, Study Researcher, University of Córdoba
Numerous steering modes are available on Sergius, including front (or rear) steering, which turns one axle; reverse front-rear steering, which turns both axles for a smaller turning radius; and a new hybrid steering system, which allows the vehicle to move forward in parallel while the rear axle also turns, albeit less.
This corrects the front trajectory and improves straight line performance when the tractor follows waypoints.
The tractor was tested in an intensive olive grove to assess its various modes. The hybrid mode worked best for straight sections, and the inverted mode was best for making precise turns. Depending on the demands of its maneuvers, the tractor can switch between its various steering modes.
Sergius, Body and “Mind”
The technology we have incorporated is necessary for autonomous navigation: two LiDAR sensors, one in the rear and one in the front; an inertial unit, which measures acceleration and inclination; a digital compass, to monitor the tractor's direction; and a high-precision GPS system. All the programming was carried out using the ROS (Robot Operating System) environment, which, being open source, allows other algorithms to be implemented and code to be shared with other research teams.
Sergio Bayano, Study Researcher, University of Córdoba
According to the researchers, the vehicle uses a diesel and hydraulic propulsion system because “we know that the future is electric, but agricultural machinery demands a lot of power and torque, so an electric motor would have to be huge, and there would be no batteries that could last a whole day of work.”
The two panels they included are one for the robot's hydraulic system and various actuators (the body) and another for its programming and decision-making (“mind”). The robot can be controlled with a computer, tablet, or smartphone.
“We could simplify by saying that one part decides the direction and the way to head in it, and the other simply carries that out,” they clarified.
This work demonstrates that scientific advancement is already in place and is only awaiting adoption and adaptation by businesses in the industry that could commercialize it. Researchers are also willing to work with the industry to advance the knowledge and technology created.
Journal Reference:
Bayano-Tejero, S., et al. (2025) Design and field validation of a Dual-Axle steering system for autonomous tractors. Computers and Electronics in Agriculture. doi.org/10.1016/j.compag.2025.110000.