Berry robots ‘within a few years’
One of the major concerns Scottish raspberry growers currently have is a shortage of pickers – an issue that will be aggravated with restrictions on migrant labour coming into play this season.
But this week, Dr Michael Stoelen from the University of Plymouth claimed that raspberry growers’ concerned about labour availability could be using commercial robot harvesters on farm within five to ten years.
Speaking at an Agricultural and Horticultural Development Board event, Dr Stoelen revealed his team had built a prototype robotic arm which can pick a raspberry without damaging it in 12 seconds; a speed which they believe once the robot is commercialised can be halved.
Stoelen stressed that human pickers would still be required as the robots would just be able to pick the more accessible fruit with human pickers there to pick the fruit left behind by the machine.
“The challenge with designing robots such as these is not just in the delicate nature of the raspberry, but also ensuring they can cope with having people around them, as well as other complicating factors such as poles, sunlight and complex foliage.”
In building the prototype robot, Dr Stoelen’s team focused on human biology developing an arm which mimics a human’s ability to shift between being robust and delicate when needs be. “We looked at human muscles, such as
the biceps and triceps, and the way humans can flex and stiffen those muscles depending on the situation. We’ve also been using ‘deep learning’ to build a large database of raspberries which will make it easier for the robot to classify and grade them.”
Raspberry harvesters have been available for almost 40 years but up until now they have all operated on the basis of shaking the fruit from the bushes. The fruit collected in this way heads for the jam/yoghurt market as it is often bruised and bleeding and is not suitable for fresh market sales.