Development of sensor guided precision sprayers

Sensor guided precision sprayers were developed to automate the spray process with a focus on emission reduction and identical or increased efficacy, with the precision agriculture concept in mind. Within the project “Innovations2” sensor guided precision sprayers were introduced to leek, strawberry, and pear production systems. This paper focusses on the combination of sensor signals and spray technique. The development of decision algorithms from sensor data and the translation to applied spray volumes is explained. Validation of the spray distribution was made with spray deposition trials in the case study of the strawberry sprayer. The sensor guided sprayer applied on average 11% less spray volume per hectare than conventional boom spraying, with an increased spray deposition on strawberry leaves of 56% on average. The decision algorithm that was used to convert crop canopy density to applied spray volume rate is still under development and has to be improved to balance between lowering the dose and keeping acceptable efficacy. Though, to realise accurate decision algorithms, thorough dose effect studies are required in addition to spray deposition measurements that validate the technical spray results.