Science - June 9, 2005

Field robot runs amok

‘We still haven’t got our robot quite under control,’ says Barry van Dongen. The Agrotechnology student is one of the creators of Rowbo, one of the twelve field robots that will be competing next week against contestants from countries including Germany, Finland and Japan.

The international field robot event will be held on 16 and 17 June in Wageningen. The robots have to negotiate a maize field and count the number of plants without flattening them.

Tension levels are rising among the Wageningen robot makers as the unforeseen problems mount. Van Dongen: ‘During the test-drives our robot sometimes suddenly started going backwards really fast and then forwards. We have to find a solution quickly. We’re also not sure about the right tyres. The winner last year had caterpillar tracks, so we thought, that’s the answer. But our caterpillar tyres come loose sometimes. That would put us out of the competition, so now we’ve gone back to normal pneumatic tyres.’

The Rowbo uses ultrasonic sensors to negotiate the field and an infrared sensor to count the maize plants. ‘We still need to make a number of adjustments. There’s a lot of sticky tape involved, and we still have no idea what we are going to do for the freestyle session.’

The Plant Research International team behind the robot Sietse is more confident and is going for victory. Last year they finished second, behind the winner from A&F. Team leader Dr Frits van Evert: ‘We had hoped to be able to take revenge, but our A&F neighbours are not competing this year. Last year it was a real local derby. Who are we afraid of? We’ll have to wait and see. I’m expecting a much higher level compared with last year; the Germans could prove unexpectedly dangerous.’

The robot Sietse took part last year, but the creators have now mounted a pc on the robot which can process more images per second from the camera that the robot uses to see. Hopefully this will enable the robot to manoeuvre with more precision around the maize field. The robot has also been fitted with a gyroscope, an instrument that measures the rotation, to ensure that the robot turns exactly 180 degrees. ‘We’ve copied this from last year’s winner,’ says Van Evert. ‘For the freestyle we are going to get our robot to recognise the potato plants among the maize. This may even have practical application in fighting potato diseases.’ / HB

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