By Dr Matt Felicetti, Lecturer, Department of Engineering, La Trobe University
Grapes are the largest fruit industry in Australia, with thousands of growers nationwide. Winter pruning is one of dried grape production's biggest time and labour-consuming activities.
The typical approach is to manually prune, which involves finding labourers, training them, and then pruning by hand. These activities financially impact growers and limit the scale of production, and concern is rising about the availability of labourers to do this job given the increasing labour shortages within the Australian agriculture sector.
Whilst there are automated solutions for pruning in agriculture, currently, there is no commercial automated solution for grapevines due to the complexity of the vine.
Collaborating across sectors
Dried Fruits Australia, an industry body representing growers of dried grapes, has been at the forefront of trying to find solutions to reduce the cost of pruning. Partnering with the Malle Regional Innovation Centre, an investigation into the feasibility of a mechanical pruning system with La Trobe University’s Robotics, Automation, Mechatronics, Prototyping, and Sensing (RAMPS) team commenced in 2019.
From here, funding was raised by Dried Fruits Australia in conjunction with Trigg Industries and AusIndustry Innovation Connections, for researchers Associate Professor Robert Ross and Dr Matt Felicetti, as part of the RAMPS team, to develop a prototype solution for cordon-based vine systems.
The aim was to create a semi-automated solution mounted to a tractor, where an operator would drive a tractor down a row, and a four-blade cutting head would extend and retract based on the best point to cut.
Several ideas were brought forward for trial. The initial prototypes focused on sensors and camera vision, and the electric powering of a rotary cutter mounted on a tractor.
After initial testing in the field with Dried Fruits Australia Consultant Field Officer, Stuart Putland, it was clear significant improvements were needed. Observations were made, and discussions with growers were collected on where the prototype could be improved. This demonstrated the importance of iterative testing, conversations with local growers, and how their feedback is crucial in the development process.
Testing and development
Significant developments were made after the initial rounds of testing. The third prototype brought many new innovative ideas, utilising a 3D LIDAR sensor and machine vision with a novel 3-dimensional light detection and ranging sensor to improve determining the cutting position, a four-bar mechanism using an electric actuator for moving the cutting head, the use of hydraulic powering of the cutting head, and many other useful additions.
Unfortunately, testing and development were slowed due to COVID-19 and related lockdowns. Once testing resumed in 2022, the solution showed promise of being able to prune reliably and accurately at a set speed, with many growers becoming keen to get involved after seeing the prototype in action.
New ideas were brought about, including GPS speed estimation to compensate for the tractor speed changes, a user interface to allow the operator to make changes to settings and automated retraction of the cutting head to prevent cutting of posts.
The project concluded with testing by dried grape grower Stephen Bennett. The system demonstrated that it could run at around 1.4km/h, which is around 10 times faster than manual pruning.
Stephen has continued testing and receiving support from La Trobe University researchers, pruning his entire field using the system.
Next steps
Dr Ross Robert and Dr Felicetti, in collaboration with Dried Fruits Australia, plan to publish their engineering design, research, and results for this project. This publication aims to spur further research and development, highlighting the significant improvements that can be achieved.
RAMPS and Dried Fruits Australia continue their collaboration, showcasing the pruner at various events, including the recent Lower Murray Water Growers' Conference and Mildura Field Day. The pruner has garnered considerable interest from growers, prompting exploration of various options to transition from the prototype stage to widespread availability.
This promising development could potentially revolutionise the grape industry, significantly reducing the cost and time of pruning and increasing the scale of production.
From mechanical whispers to bountiful harvests, Dried Fruits Australia and RAMPS’ innovation promises a fruitful transformation for the grape industry.
La Trobe Industry Communications and Media Enquiries: industry.engagement@latrobe.edu.au
