Robots could be designed to include many agricultural techniques using a limited set of tools and replacing the human laborers.

A fully autonomous agricultural robot should have the ability to understand the environment, work for an unlimited time without any operator intervention, capable for environment adaptation when changes occur, and to ensure the security for humans.

The number of commercial agricultural robots is still limited for a moment, but there is the assumption that in the near future their number will increase significantly.

Even is a tractor modified to work autonomous or a robotic platform powered by sunlight, in this article we make an overview of autonomous agricultural robots capable to recognize plants, works with high accuracy on large areas, and could be used for many agricultural operations.

Autonomous Robot Tractor

Wide range of maneuvers and high accuracy.
From Belgium comes one of the most advanced self-steering tractor designed by a common research team from Katholieke Universiteit Leuven (KU Leuven) and Flanders’ Mechatronics Technology Centre (FMTC). The aim of these engineers is to build a robotic tractor able for a wide range of maneuvers and working the ground with high accuracy. They pass the problems with uneven and inconsistent terrain that can change the direction of the tractor.

The autonomous system component includes a system to act the acceleration and steer, processing unit, and sensors to locate the position including GPS system.

Sensors and a powerful computer is not enough to keep the tractor on the right path. The development team creates an application where the user calibrates the robot according to each terrain type.

Hortibot

Autonomous robot for removing manually, spraying or cutting the weeds.
Hortibot was born in the labs of Aarhus University in Denmark and was built by combining the Spider remote controlled robot with research platform AgRobot designed by the Danish agricultural engineers. The result is an autonomous vehicle for farming, a robot used to remove weeds manually, spraying or cutting with flames or laser.

Row by row the robot navigates the entire field using vision system and positioning system. Starting from a corner of the field the robot cover each row and at the end of the rows turn back and enter to the next row. Using an ECO-DAN camera, GPS system, and a gyro sensor Hortibot can reduce the herbicide usage by 75 percent since it can recognize up to 25 different kinds of weeds and can use up to three methods to remove the weeds from the land.

The cell sprayer system is perhaps the most interesting method for removing the weeds. The system uses a camera for taking continuous picture of the ground and based on images analysis the system locate the crops and weeds. Once the weeds are located the system sprayed on a limited surface.

This method is very expensive in terms of time, this could be a big disadvantage, but is very friendly with the soil while this is not affected.

The robot can be operated remotely by an operator, and in case that is for the first time when the operator meet the robot, a short training is sufficient to operate the robot.

Lettuce Bot

With 98 percent accuracy the robot exterminate the weeds without affecting the lettuce.
Targeting as a terminator for weeds, Lettuce Bot is an advanced agricultural robot used to exterminate the weeds without affecting the lettuce. With 98 percent accuracy in selecting the weeds, Lettuce Bot has a complex vision algorithm that works in three steps to detect and then slice and inject a minimal quantity of herbicide in the soil that not affect the lettuce.

Three steps for detecting the weeds. Vision system has implemented three algorithms that work in three phases. First time is identified if the camera recognizes a plant, the second step is to determine if the plant is a lettuce or weed, and the third step is to determine the moment of execution.

This vision system could be updated to work for other plants by adding a database to compare the images captured with the plant. Engineers try to increase the production of the robot by increasing the speed up to 3 miles per hour while the accuracy remains at the same level.

Vitirover

Solar autonomous robot for cutting grass between grape vines.
Green, friendly with the nature, Vitirover is an autonomous robot designed to cut the grass and weeds between grape vines. Build by a French company the little robot uses a solar panel to produce energy to power the electric motor and electronic parts. Using a battery to store energy is not the best solution since the robot has to navigate on large areas.

As long as the sun is up the robot can work without pause and cut the grass and weeds at a speed of 500 meters in an hour.

For farmers are very important to use technology friendly with the grapevines. Vitirover uses sensors and GPS system that keeps the robot away from grape vines.

Wall-Ye

Pruning vines robot with soil condition sensor and complex vision system.
Another French company and another vineyard robot capable to pruning 600 vines in one day. Based on four wheels, Wall-Ye navigate on wine rows using six cameras and GPS system to know at every second the position in space.

Two arms are designed to prune vines and removing the unproductive young shoots. The same robot, but another sensor measures the soil conditions and the state of the grape vines.

In memory the robot stores the maps of the vineyard while the GPS system sets the position of the robot.

The six cameras used for vision and a complex algorithm are used to detect the grape vines and to prune the vines.

John Deere Spraying Robot Tractor

Autonomous tractor for several agricultural operations designed to work continuously day and night.
Take a series tractor, good one like John Deere brand and transforming into a robot is perhaps the simplest project to build an autonomous robot for several agricultural operations.

With capacity for day and night working, the robot tractor uses the complex vision system, GPS system, a ground speed radar and one unit for inertial measurement that keeps the robot on the right paths in the field or an orchard.

Two color cameras are the eyes of the robot programmed to detect any obstacle.

Designed to be used by a human driver, the tractor was changed with control systems for steering, braking and acceleration. All control systems working based on position system information and follow the path with speed range between 5 and up to 8 km/h.

Soil Sterilization Robot

Mitsubishi robot for injection into the soil substances against weeds, bacteria, fungi and viruses.
Mitsubishi Research Institute is on the map with a robot for soil sterilization designed to be used in limited areas. The robot injecting into the soil substances against weeds, bacteria, fungi and viruses without affecting the plants.

The robot uses the laser triangulation system to detect the position and works autonomous.

Armadillo

Robotic platform designed to work with high accuracy in agricultural applications.
With a name inspired by an armor shell animal called Armadillos, Armadillo is an agricultural robot build by engineers and researchers from the University of Southern Denmark and Aarhus University. The robot is designed to work with high accuracy between the row crops on any type of terrain and in any direction.

In this new version engineers replace wheels with tracks for a good stability on lands and an increased mobility. Electrical motors are powered by a battery with 55 Ah capacity.

Plans of the future version include ROS technology and an advanced autonomous system for navigation.