Letter From Europe: Robots, electric drive power and mechanical weed control start to come into favour

Thursday, January 31, 2008

One of Europe's top agricultural engineering researchers predicts a farming future with soil protection laws, robots that recognize and eliminate weeds and electric drive instead of pto power for farm machinery.

by NORMAN DUNN

Prof. Karlheinz Köller, a precision farming expert from Stuttgart's Hohenheim University, is convinced that the most important challenge facing farmers is the protection of soil and water, while still producing as much food as possible.

"In fact," he told an international gathering of farmers this November in Germany, "water is actually disappearing faster than our mineral oil reserves at the moment. We are also losing farming land at alarming rates in some countries."

This is why Köller expects more laws for farmland protection. And for optimum utilization of this dwindling resource, he sees increasing attention given to avoiding compaction damage and soil erosion losses. Over in Scotland, the government has beaten the rest of Europe by already announcing possible penalties for farmers who leave fields in a condition where they are liable to windblow and runoff.

Part of the answer to such problems, says the professor, is more use of cover crops and conservation cultivations.

But the resultant higher levels of organic matter in the top layers of the field surface represent sizeable obstacles to optimum drilling. This is why he sees an immediate requirement for a new generation of "intelligent" tillage-drilling combinations. These, he hopes, will be designed continually to analyze slope gradient, straw cover, type of soil, soil moisture on and below the surface and then automatically make the necessary on-the-go adjustmentsto cultivations and the sowing depth.

Modern high-capacity field operations also represent a sizable threat to soil stability and health and here extra weight on certain soils has to be curbed with strict regulations on permitted "footprints" of farm machinery.

"There's a strong argument for some sort of 'ground protection law' governing this sort of compaction risk, but also controlling fertilizer and pesticides applied," Köller told his international audience.

One strategy for reducing field traffic weight throughout the growing season uses comparatively lightweight unmanned robot vehicles for jobs such as spot spraying, soil sampling or weed control. Agricultural universities in Germany and the Netherlands have already taken up the challenge and established small departments - in some cases, sponsored by well-known farm equipment makers - dedicated to developing these types of agricultural robots.

Some are already taking part in international competitions to find the best performers, using ultra-sonic, infrared and also camera-controlled steering and plant identification systems as well as GPS navigation where required. For example, weeds can be "recognized" in a standing crop and, in the future, hit with a spot spray or grubbed out where there's room between the rows.

From the environmental protection side, more accurate selective spraying by such robots means that fewer chemicals are applied, which in turn also reduces costs for the grower. And considering the substantial reduction in labour costs involved - some of the researchers involved in robot development reckon that one skilled operator could control a fleet of small field vehicles - mechanical weed control could also become more popular, and cheaper, than it's been for a long time.

Some robots have already made it into the commercial market, including the "Hortibot," funded by the Danish government and now produced by a conglomerate of companies in that country. This compact machine has a computer brain capable of identifying around 25 different plants, including grasses, crop plants and weeds, and then frazzling the unwanted plants with a laser beam.

Köller's crystal ball for farming's future also reveals a promising future for electric drive instead of pto power for farm machinery.

"Look at railway trains and machinery on-board ship. There are many similar industrial applications that have changed to electric power many years ago. It could be ideal for farming too," he suggests. "Electric drive is insensitive to heat, cold or dirt and offers a longer working life between services compared with internal combustion power. There's little wear involved because there are no contact parts in the motors apart from bearings. The concept can survive high overloading and the drive is much quieter than the alternatives."

He sees the power coming from systems like the present John Deere E-Premium Series tractors with their additional crankshaft-driven generator, which not only powers on-board equipment such as pumps, fans and air conditioning but also supplies 400-volt power to mounted or trailed implements.

German fertilizer spreader manufacturer Rauch already has a machine on the market to take full advantage of this new development - a spreader with two broadcaster discs driven by electric motors instead of pto power. The result: quieter running and precisely controllable disc speeds for more accurate spreading patterns. And, on top of these advantages, trials indicate that power from this separate generator on the tractor also saves diesel fuel. BF

Norman Dunn writes about European agriculture from Germany.