RESEARCH conducted by PhD student Steven Rees and Dr Cheryl McCarthy of the National Centre for Engineering in Agriculture (NCEA) based at the University of Southern Queensland, has developed an improved imaging system that is a major step forward towards automated species specific weed spraying.
"Our research demonstrates that discrimination of weed species in real-world on-farm conditions is achievable using combined colour and depth image analysis," Dr McCarthy said.
"The proof-of-concept technology demonstrates discrimination of weed species by using cameras to detect broadleaf and grasses, and even has the potential for individual broadleaf or grass species to be identified automatically.
"It is an important breakthrough because alternative weed control strategies are required as the cotton and grains industries face growing herbicide resistance in minimum and no-till farming systems."
Weeds cost Australian agriculture more than $4 billion dollars each year, including control costs and lost production.
Dr McCarthy said more research was needed to further advance the technology so that it could be integrated with a weed classifier system linked to the spray trigger.
If the technology was realised, she said the reduction in herbicide usage, coupled with precise knowledge of the species of weeds present, would enable a much larger range of herbicides to be viable, therefore reducing the risk of herbicide resistance developing.
Dr McCarthy said the challenge was to develop a precision sensing system with the "capability to extract whole leaves for classification from a scene containing many weeds".
The team tested two camera systems - a combined colour and depth camera and a high resolution colour camera - for their ability to capture effective images of weeds for analysis in real-time.
The results encouraged the researchers to develop a new image analysis technique that can discriminate between grass and broadleaf species, and between different broadleaf species.
The NCEA is now testing its research through grants from the Sugar Research and Development Corporation, Horticulture Australia Limited, and Botanical Resources Australia, which it hopes will develop the technology from the proof-of-concept stage towards commercialisation.
Update your news preferences and get the latest news delivered to your inbox.