21 January 2000

High-tech hoe takes off

Organisers of Denmarks Agromek event consider it to be

the largest exhibition of agricultural machinery in northern

Europe. With over 1200 companies occupying 15 exhibition

halls and more than 80,000 visitors, it is a claim which

clearly has some substance. Andy Collings reports

THE need to reduce reliance on pesticide use in Denmark has also encouraged the development of a computer-controlled steering system for interrow hoeing of sugar beet and a range of vegetable crops.

Making its European debut was a system built by Eco-Dan which uses a combination of cameras and microchip technology to allow weeding tines to run within 5cm of plants at speeds of up to 10kph.

There are two modes to the system, one for use before the crop has emerged and the other when the crop has 4-5 leaves. For pre-emergence operation, a hollow groove 10cm wide, 7cm deep needs to be formed in the centre of the rows when the crop is drilled.

In this mode, a light is shone on the hollow and the computer, via the camera, transfers images to a reference line. The computer then checks the position of the implement in relation to this reference line and then instructs the hydraulic steering system to make corrections if the two reference lines do not match.

When the crop has emerged, two cameras are used – one on each row – which provide the information for the computer to perform any required corrections.

Eco-Dan has developed its own hydraulically steered headstock which allows the hoeing unit to be moved 15cm in each direction – speed of movement can also be controlled.

The system has also been adopted by implement manufacturer Thyrogod which has fitted it to its 12-row inter-row weeder, albeit with a totally different steerage system.

Computer controlled steering for inter-row hoeing operations could result in reduced dependence on pesticide use for crops such as sugar beet.