This article is part of our special report How is tech revolutionising the agricultural sector?.
As farmers are urged to reduce their use of plant protection products (PPPs), they are forced to take on manual weeding, a tedious task for which manpower is hard to find. But could so-called ‘robot weeders’ provide a solution to this problem? EURACTIV France reports.
Before weedkillers were introduced to the agricultural sector, weeding used to be a mammoth task, which was done by hand. However, as the reduction in the use of pesticides has become a political priority and organic farming is developing across the board, the issue of weed control is back on the table.
Besides being tedious, weeding is also very labour-intensive.
“About a third of a market gardener’s working time is spent on weeding. And it’s very difficult to find labour,” explained Maët Le Lan, who leads the South Brittany’s market gardening experimental station and has been working for several years on improving the working conditions of farmers.
This means that weeding tasks are mainly carried out by market gardeners, many of whom suffer from musculoskeletal disorders.
Improving working conditions
Based on this observation, the company Naïo Technologie has launched the development of a robot weeder.
“The basic idea was based on discussions we had with farmers who had great difficulty finding labour because of the drudgery of weeding” explained Gaëtan Séverac, robotics engineer and co-founder of Naïo Technologie.
Oz, the small electric robot which has been developed by Naïo Technologie over the past few years, can weave its way through the rows of vegetables thanks to its inbuilt GPS guidance system.
With the help of a camera and a laser, Oz locates its path between salads and tomato plants to avoid possible obstacles.
“The camera and the laser are used to differentiate between a weed and a salad and eliminate the right one” explained Gaëtan Séverac.
A hundred or so market gardeners have already equipped themselves, mainly in France, but also in other countries such as Belgium and the Netherlands.
“For more than 30 years, research projects have been carried out in the field of robotics and weeding or harvesting. But they were limited by cost and technology,” said the engineer.
Technological advances have now opened up a whole range of possibilities.
Yet, if the solution looks promising on paper, several obstacles stand in the way of Oz, as the technology is not yet fully developed.
“The robot makes mistakes when weeding. Sometimes if a weed is too high, it will go around it and damage the vegetable plants,” said Maët Le Lan, who has been experimenting with the robot for five years at the experimental station.
The idea is to test the robot’s different updates to be able to advise farmers in their investments, especially given the robot’s €25,000 cost. “We must be able to tell market gardeners whether it is worth investing or not” explained the manager.
Today, the robot’s performance varies according to the farm, the farmers’ appetite for technology, etc.
But besides the cost and improvements to be made to Oz, the robot’s programming is also made more complicated by the wide variety of crops, including cabbages, turnips, salads, carrots, parsnips, of which are spaced out differently. Such information needs to be programmed on Oz’s route.
“Today, half of our customers are organic farmers. But in the wine growing business, we only have winegrowers who would like to switch to zero weed control,” Gaëtan Séverac explained.
These days, we are more expensive than chemical weed killers, so farmers who choose to use chemical weed killers are in a real effort to reduce the use of chemicals”.
Robotics to the rescue of weed control
Besides Naïo Technologie creating the robot Oz and vine-weeding-robot Ted, other firms have also started to work on developing robotics to deal with weed management.
Touti Terre, an SME based in Haute-Savoie, has developed the Toutilo robot, which allows market gardeners to weed by hand, but in a far more ergonomic position.
The robot circulates between the rows of vegetables and the market gardener installed on top of it can thus avoid repeating the so-called “stand and kneel” positions.
As a result, the robot does not just reduce the working time devoted to weeding by about 20% but also makes the work less tiring.
Finally, other machines offer the use of ultra-precise weed killers.
This is the case of the Ecorobotix robot, which is more targeted at large cereal crops and allows a micro-dose of weed killer to be sprayed on the exact location of the weed.
[edited by Gerardo Fortuna and Zoran Radosavljevic]