Developing an automatic guidance system for tractors in fruit farming.

摘要

In orchards, cultivation measures such as mulching and plant protection require 20 to 30 machine-related operations per season. Automatic guidance systems are of key importance in terms of making life easier for the driver and providing further options for both partial and complete automation of operations. To date no suitable systems have been available for tractors used in fruit farming. The aim of the ART project was to develop an easily retrofittable steering system from commercially available components. The system was meant to be quickly transferable from one tractor to another, as well as having a high level of functional safety and a good price-performance ratio. A control system based on a software controller was created as a development platform. Laser and ultrasound sensors scan the plants and use them as a guidance line. The steering consists of a friction-wheel drive on the steering wheel; the steering angle is determined with an ultrasound sensor. A satisfactory steering accuracy of +/-10 cm was measured in field trials. The system concept meets present day requirements of an automatic guidance system, and constitutes a building block for further automation. Together with driverless transport systems technology, it provides new opportunities for structuring tractor-based tasks in orchards.