Farm robot Thorvald can help improve crop yields

2016 was a crisis year for Norwegian strawberry producers as major parts of the crop were lost due to fungal infections.

In time, Thorvald the agricultural robot may become instrumental in the prevention of fungal infection without the need for pesticides.  Thorvald can monitor the strawberry fields, constantly watch for attacks from fungi and mites, treat the plants without recourse to pesticides and even help with harvesting.

International publicity

In fact, the many ways in which Thorvald can assist farmers have recently generated substantial international media coverage as British media have speculated that Thorvald, in the long term, may be able to plug a post-Brexit labour crisis.

«Meet Thorvald, a member of a new generation of farm robots being readied to plug a labour shortage on Britain’s farms that may soon be exacerbated by Brexit,» the Financial Times writes (behind paywall).  

The latest crop of robots heads for the fields, The Times reports (behind paywall). Mass produced Thorvald farm robots could replace human workers, The Daily Mail claims.

Pesticide-free treatment of fungal and mite infestations

"With Thorvald the farmer has a special agent out in the field the whole time, monitoring the plants and taking photos, which significantly reduces the risk of mildew and other kinds of damage," says Professor Pål Johan From, the robotics professor who developed Thorvald and is head of the robotics group at Norwegian University of Life Sciences (NMBU).

Trials have shown how the agricultural robot can be used to direct an extremely low intensity ultra-violet light onto strawberries to zap mildew as it travels along rows, and the scientists are currently testing methods to perfect this procedure in order to combat fungal infections without the use of pesticides.

Ultra-violet, or UV, light is electromagnetic radiation with wavelengths between the visible spectrum (400 nanometres) and x-rays (4–20 nanometres). UV light is subdivided into three groups depending on the wavelength. In Thorvald's treatment of strawberry plants UV-B light is used (280–315 nm).

Energy from UV light can destroy microorganisms such as mould by breaking down chemical bonding in the DNA so that the cells die. This technique is frequently used to get rid of fungal growth in homes after flooding, or to rescue books or museum artefacts which have been attacked by mould.

Ongoing tests

Thorvald is, strictly speaking, only a prototype of an agricultural robot.

Although different versions of Thorvald are already rolling around in British and Norwegian fields, helping out with everything from strawberry production to the development of new plant species, it is only as part of various research projects.

"If you offer an agricultural robot that can manage, for example, weed removal, it must have close to 100 per cent uptime in order for it to be a success. If Thorvald was to be marketed today, the investment itself would be justified even with 50 per cent uptime as using UV-B light to treat fungus and mould attacks on strawberry plants is something that cannot be solved using conventional methods currently available," explains From.

In order to guard a field against attacks from fungi and mould, Thorvald can be fitted with hyper spectral cameras which photograph the plants whilst Thorvald travels across the fields. These can take photos showing both visible and invisible light, and can register the light intensity within several hundred wavelength parameters.

From tractor to robot 

Thorvald is, in many respects, really only a type of tool carrier; a robotic platform that can be connected to various tools - much like a tractor.

To start with the scientists developed tools that enabled Thorvald to help with sowing, fertilising and removing weeds, but during development they have added tools that allow Thorvald to help with harvesting, as well as guarding the fields against fungal, mould and plant diseases, and radiating plants with UV-B light. Thorvald will also be able to estimate the crop yield to help farmers better plan how much help they will need to engage in harvesting.

The photos that Thorvald takes out in the fields can be analysed using advanced image analysis tools with specifically-programmed algorithms to calculate the size of a crop or look for mildew, for example. Students involved with the robot group at NMBU are working on the constant development of new algorithms which will widen Thorvald's repertoire, or toolbox, if you prefer.

More environmentally-friendly and efficient agriculture using robots

Thorvald is, moreover, a small, lightweight robot. This makes it easier to navigate in difficult conditions with a lot of water; something which is becoming an increasingly greater challenge in Norway going forward.

"In Norway we get a lot of precipitation at the most inopportune times, and Thorvald is better equipped to tackle this than larger machines such as tractors," says From.

The size and weight of the agricultural robot means that you also avoid the soil compaction that a tractor causes; something that can cause up to a 20 per cent reduction in crop yield today. Robots such as Thorvald are basically better than traditional agricultural machines such as tractors in every way, according to From.

"The robot doesn't cause pollution, as opposed to the tractor it is replacing. It doesn't destroy the earth in the same way as larger, heavier machines like tractors. It facilitates the production of more food and it creates better growing conditions for plants," he says.

"I see an enormous potential in robotising agriculture. To begin with we want to have a more sustainable agriculture with reduced emissions and earth compaction. We also want much more accurate systems that enable us to produce more food on the same area of land than what is currently the case. Intelligent systems will also contribute to reduced use of pesticides, and in many cases we will see that we can eliminate the use of pesticides completely by adopting more intelligent methods. This results in a win-win situation for both food producer and the consumer," he concludes.

Mass production next

With full-scale testing through the entire growing season this year the scientists shall ensure that the technology is sufficiently robust and dependable to be made commercially viable, and the robot will be put into mass production.

This will take place through the project "Agriculture 4.0: Intelligent and self-propelled robots for cost-efficient fruit and vegetable production", financed through the Research Council of Norway's "FORNY"-programme.

Thorvald is being systematically tested in both Norwegian and British strawberry fields, more specifically in Lincolnshire and Sylling.

See the Norwegian version of this article here.

Published 28. April 2017 - 13:21 - Updated 8. September 2020 - 14:59