In Search of Farm Robots: Ch3 Switzerland, France and England

This article originally appeared in “The Grower”

A desire to reduce soil compaction and avoid high and inefficient use of chemicals and energy inspired Steve Tanner and Aurelien Demaurex to found eco-Robotix in Switzerland.

Their solution is a light-weight fully solar-powered weeding robot, a 2 wheel drive machine with 2D camera vision and basic GPS. Two robotic arms position herbicide nozzles or a mechanical device for precision weed control.

Steve Tanner lab testing the exoRobotix vision and robotic weed control system

The ecoRobotix design philosophy is simplicity and value: avoiding batteries cuts weight, technology requirements and slashes capital costs. It is a step towards their vision of cheap autonomous machines swarming around the farm.

 Bought by small farms, Naio Technologies’ Oz440 is a small French robot designed to mechanically weed between rows. The robots are left weeding while the farmer spends time on other jobs or serving customers. Larger machines for vegetable cropping and viticulture are in development.

Prototypes V1, V2 and V3; precursors to the Naio Oz440 show the steps in a robot’s development

Naio co-founder Gaetan Severac notes Oz440 has no GPS, relying instead on cameras and LiDAR range finders to identify rows and navigate. These are small machines with a total price similar to a conventional agricultural RTK-GPS system, so alternatives are essential. 

Tech companies have responded and several “RTK-GPS” systems are now available under $US1000. Their accuracy and reliability is not known!

Thorvald an example of research collaboration: Norwegian University robot being automated at University of Lincoln show the common design of four wheel steer and four wheel drive

Broccoli is one of the world’s largest vegetable crops and is almost entirely manually harvested, which is costly. Leader Tom Duckett says robotic equipment being developed at the University of Lincoln in England is as good as human pickers at detecting broccoli heads of the right size, especially if the robot can pick through the night.  With identification in hand, development is now on mechanical cutting and collecting.

In 1996, Tillett and Hague Technologies demonstrated an autonomous roving machine selectively spraying individual cabbages.  Having done that, they determined that tractors were effective and concentrated on automating implements. They are experts in vision systems and integration with row and plant identification and machinery actuation, technology embedded in Garford row crop equipment. 

Parrish Farms has their own project adapting a Garford mechanical to strip spray between onion rows. Nick Parrish explained that Black Grass control was difficult, and as available graminicides strip wax off onions boom spraying prevents use of other products for up to two weeks.

Simon Blackmore is a global leader in farm robotics thinking at Harper Adams University. His effort to address robotic safety issues includes a seven level system:

  1. Route planning to avoid hazards and known obstacles
  2. Laser range finder to sense objects and define them as obstacles
  3. Wide area safety curtain sensing ground objects at 2m
  4. Dead man’s handle possibly via smartphone
  5. Collapsible bumper as a physical soft barrier that activates Stop
  6. Big Red Buttons anyone close can see and use to stop the machine
  7. Machines that are small, slow and light minimise inertia

“Hands free hectare” is Harper Adams University’s attempt to grow a commercial crop using open source software and commercially available equipment in an area no-one enters.

Harper Adams research to develop a robotic strawberry harvester is notable for the integration of genetics for varieties with long stalks, a growing system that has plants off the ground, and the robotic technologies to identify, locate and assess the ripeness of individual berries and pick them touching only the peduncle (stalk).

So what have I learned about farm robotics?

  • People believe our food production systems have to change
  • Farm labour is in short supply throughout the western world
  • Machines can’t get bigger as the soil can’t support that
  • Robotics has huge potential but when
  • Safety is a key issue but manageable
  • There is huge investment in research at universities, but also in industry
  • It’s about rethinking the whole system not replacing the driver
  • There are many technologies available, but probably not the mix you want for your application.

As Simon Pearson at the National Centre for Food Manufacturing says, “It’s a Frankenstein thing, this agrobotics. There are all sorts of great bits available but you have to seek them out and stitch them together yourself to make the creature you want.”

Dan’s travel was supported by a Trimble Foundation Study Grant