The only gold medal awarded at the 2021 DLG Innovation Awards went to a relatively obscure German company by the name of Nexat for its reiteration of portal agriculture.
This company was formed in 2013 for the sole purpose of developing what it describes as an ‘all-in-one system tractor’, which is a state-of-the-art version of the gantry tractor concept that has been around since the mid-19th century. .
Pioneer in Kensington
A man named Alexander Halkett built what we would now call a bed system in Kensington before it became part of the larger metropolitan area.
Indeed, it was a very large-gauge railway with the steam engine located on one side of the machine while collection or supply boxes were mounted on the other, both connected by a frame or gantry.
Running on rails, it was named by its inventor “Guideway Agriculture” and appears to have been used successfully in an area where vegetables are said to have come at a high price.
Its fate is uncertain, but the rapid growth of rail transport has likely brought products from further afield, while the city’s expansion saw the borough develop rapidly with a corresponding increase in land values.
Gone but not totally forgotten
It seems that the idea didn’t do much until the 1970s, when David Dowler, a farmer from Chipping Norton, Oxfordshire, began to develop his own machine based on a Hesston rake.
David’s main concern was the damage caused by soil compaction in tillage, a concern shared by the Silsoe Research Institute who ultimately acquired a machine of his design with which he carried out his own research.
The advantages of gantry systems quickly became evident with both a marked increase in soil condition and great savings in pesticide use.
Maintaining traffic in well-defined areas of the field, now referred to as Controlled Traffic Agriculture (CTF), paid dividends across the board, as the range of tasks the gantry was able to perform widened as it grew. the condition of the soil was improving.
In 1996, a report published in New Scientist indicated that developers of the Dowler “gantry” tractor claim it could increase crop yields by up to 25%, cut farmers’ fuel consumption in half, cut fuel bills. fertilizer and reduce herbicide applications by up to 70%. % “.
Silsoe highlighted the benefits of portal agriculture
Much of the development work undertaken at the Silsoe research station, which incidentally now sits under a subdivision, was carried out by Tim Chamen who is still a strong supporter of the concept.
Speak exclusively to AgrilandTim noted that the main advantage of gantry systems is that they limit soil compaction to a dedicated area of ​​the field, both throughout the growing season and over time.
With the Dowler machines this area made up about 10% of the land, but with the much larger Nexat unit, spanning 14m, it is reduced to just 5%. Conventional systems can drive 80% or more of the field.
One of the reasons why gantry cranes require less land is that for two adjacent passes only three, rather than four, tracks are needed because one end will use the same track going up as it is going up.
A different approach to fieldwork
He also notes that for optimal effect, these wheel tracks should become semi-permanent, with the same lines used every year.
Eventually a hardened “base†of the soil builds up which remains uncultivated but better able to support the weight of the machine during wetter periods.
Another observation he conveys is that the great advantage of the Nexat machine is that rather than tools hanging from the gantry, the machine docks with them from the side.
The “U†shaped construction of the machine allows attachment to work modules from their sides rather than from above. This speeds up the process and allows better automation.
Unfortunately, neither the Dowler machine nor the work done on the gantry systems at Silsoe has achieved commercial success, although the emphasis on the importance of avoiding soil damage and the development of CTF may be to be the greater legacy of the two.
Various other attempts have been made around the world, including Japan, Russia, and California, but no widely accepted or mass-produced machine is currently on the market.
Join Nexat
This situation may well be set to change with the Nexat gantry system (a short form of Next Agricultural Technology) announced in December of last year.
The company behind the machine is Kalverkamp Maschinenbau GmbH from Germany, an engineering consultancy firm specializing in helping businesses to design and manufacture machines, primarily in the agricultural sector.
In 2013, she formed Nexat to develop the gantry in partnership with several other companies and organizations who brought their specific skills and knowledge to the project.
Ready for stand-alone operation
Past attempts to commercialize portal agriculture seem to have collapsed on rock with competition from conventional manufacturers taking into account the damage caused by soil compaction and tailoring their products to minimize it.
This, together with the ever increasing width of tram tracks, has eroded the obvious advantages offered by portal agriculture. However, a definite advantage that it offers is its adaptability to autonomous agriculture.
Designed from the start to operate autonomously, the Nexat machine will be able to take advantage of the latest developments in digital agriculture as well as all the new features that will arise.
It is claimed that the system will take care of every stage of the work, from cultivation to sowing, plant protection and harvesting; everything will be possible without the need for an operator.
Each field operation will have a dedicated unit that adapts to the gantry. This includes a cereal harvesting unit with a 5.8m long axial flow separator.
It looks like moving the combine could turn into another scalp it carries.
The modular approach means that every tool, in effect, becomes self-propelled, further eroding the old coupling of a traction unit with a work tool, be it an ox or a tractor. .
Road transport, often cited as a major stumbling block for autonomous tractors, is achieved by retaining a driver’s position so that it can be driven manually between fields.
Power is currently supplied by two 550 hp diesel engines with electric track drive. Hydrogen fuel cell technology is expected to be used in the future.
A partnership at the service of innovation
One of the problems encountered in the early attempts to market these machines was the lack of support and investment from other companies.
Nexat circumvented this obstacle by bringing together several companies during the early stages of development.
The main partner is Vaderstad who have produced a modular series of tools and drills that easily attach to the gantry and are specially designed for use with it.
The company notes that it has “played an important role in the development and adaptation of the respective module solutions and will offer our machines as modules in the new crop production system.”
Other partners include Herbert Dammann GmbH, specialist in fluid applications, Geringhoff GmbH, which is involved in harvesting equipment and the two German universities of Osnabruck and Bremen.
