Australian robotic mango harvester nearing commercialisation

The automatic mango harvester is now nearing commercialisation. “This is a university project”, professor Walsh says. “We’ve got it to this point but at this stage we haven’t locked in a commercial partner. We are still looking for the right group. It’s launchable but somebody’s got to take it on.”

Modules of 4 arms

The harvester consists of a horizontal bed of arms, with modules of 4 arms. Each module has its own camera and control. The camera locates the fruit and allocates it to an arm, that picks the mango. “You can have as many modules as you wish. The whole question is an issue of speed”, Professor Walsh explains. “One arm is too slow.”

The auto-harvester has been turning heads within the mango industry for some time, but recently underwent substantial refinement and is ticking more boxes for industry and becoming more viable for commercialisation.

Great results in the field

CQUniversity Australia has been doing several trials with the harvester over the past years. Recently the installation of new mechanics, camera systems and grippers on the robot with MK 3 technology has resulted in great results in the field. “It’s been incremental over the years”, Professor Walsh points out. “The detection system has been improved, in terms of the accuracy of locating fruit. And new flexible grippers are doing a much better job of holding the fruit. They are less damaging for the fruit.”

We‘re continuing to make it faster and more robust

The mango-harvester has also changed from a total electrical system to a combination of an electrical system and a pneumatic system. “That’s working well”, says Professor Walsh. “But things keep improving … so we‘re continuing to make it faster and more robust.”

The prototype was out in the field recently undergoing further testing and refinement on Groves Farm, a tropical fruit farm near Yeppoon in Central Queensland, where the research team has been working with the last of the season’s crop. “Overall, we have experienced an improved harvesting success rate, particularly for bigger fruit”, Professor Walsh explains. “It is really exciting to see the technology achieving great results in the field.”

Each arm needs about 5 seconds to pick a mango and drop it. “But the speed is very dependent on the tree”, Professor Walsh explains. “And the density of fruit on the tree. You need a reasonable density of fruit to make it worthwhile doing. But we had some of the bigger mango growers from up North to have a look and they all see this as the future. They’ve mechanised the packhouses and now it’s time to mechanise the field.”

Mango industry reliant on backpackers

Getting human labour to do the job has been difficult lately in Australia. “Growers are very interested in our technology. The industry has been very reliant on backpackers”, Professor Walsh says. “With Covid this source of labour had dried up. There have been big problems in the last two years because there is no local labour for harvesting. The auto-harvester has the potential to solve some of the major labour force issues that currently limit the mango industry in Queensland.”

Australia has got a high labour cost and the harvester will eventually help to bring costs down, Professor Walsh expects. “But you still have people to drive the harvesting unit or people to look at what’s coming out of the conveyor and pick up any fruit with defects. And there still will be fruit left on the trees, so you will need people for that final pass in the field.”

_{Text continues underneath image}

Save costs and improve productivity

The end goal of the researchers is to help farmers save costs and improve productivity on farm and the quality of the picked fruit. Professor Walsh says the auto-harvester is a step toward mechanising the ‘back-breaking’ work of harvesting mangoes. “As it stands, every single mango is picked one by one by hand, in the middle of summer, with a really acidic sap which some people can be allergic to.”

Now it’s about speed – we need to just do it quicker

Professor Walsh explains the harvester is part of an integrated system which will ensure farmers know exactly how many mangos are on their trees, when they will be in perfect condition for the consumer, and when to employ the right number of people for picking and packing.

Up until now there has been some movement toward mechanising the picking process, but the new technology takes it further, incorporating a number of different technologies to help with the harvesting process. “The soft grippers are remarkably gentle on the fruit and forgiving – they will wrap around a branch and twist out of the way”, Professor Walsh emphasises. “Growers have been impressed with that function and now it’s about speed – we need to just do it quicker.”