Science - June 29, 2006

‘Building a robot is great practice’

In the future robots swarming over the fields looking for disease and weeds might become a common sight. But there will have to be considerable technological improvements before this becomes reality. During the fourth Field Robot Event, held in Stuttgart in Germany, the experts had an opportunity to show off their advances. Sietse, the creation of five PRI employees, came fourth.

You might be forgiven for thinking that the shops in Japan are full of robots that can do everything. Nothing is further from the truth, however. Even the Japanese robots are not yet really intelligent. And in agriculture, where conditions cannot be controlled like in a car factory, this is a fundamental requirement. ‘The biological variability of plants places high demands on the intelligence of a robot,’ according to Professor Eldert van Henten, chair of Agrarian Farm Technology. ‘I have developed a robot for cucumber picking. The crux of the matter is not the mechanics, but the rapid and effective translation of signals from the sensors into the movement of the robot arm.’

After three times in Wageningen this year’s Field Robot Event took place in Germany for the first time. The competitors came from six countries, including Malaysia, Finland and Chile. According to Van Henten it’s important to take part in the annual competition, both for students and researchers. ‘Robots are the future. Building a field robot is great practice for getting to grips with the technology.’

For the event, which took place on 24 June, the robots had to draw a white line to a corner flag, manoeuvre through uneven rows of maize, count yellow golf balls that were meant to represent dandelions and find a hole in a field of grass. In addition there was a speed race. The best entry from Wageningen was Sietse, built by workers from Plant Research International, which reached fourth place. The Wageningen student team, Fieldmeister, was built on a previous design, and due to limited means just scraped eighth place.

The most important difference between the Wageningen entries and the German winner Maizerati was the steering system. ‘Theirs was based on a microcontroller, ours on a PC. That turned out to be less stable. On the other hand, the microcontroller is more difficult to programme. But it was a learning experience for us,’ added Van Henten. The way forward in the future might be to seek collaboration with technical universities or polytechnics. / YdH