IN a project funded by Agri-tech Cornwall and a £ 12,967 innovation grant from the Cornwall Development Company , Robotriks has created an autonomous platform which can be built at low cost and , within a few hours , is ready to get to work .

“ The aim is to create a system which is affordable and reliable ,” says Jake Shaw-Sutton , director at Robotriks . The Robotriks Traction Unit ( RTU ) costs just £ 7,000 - almost a tenth of the cost of most others on the market .

One of the main challenges the RTU addresses is lack of manual labour on farms . “ It ’ s not about taking away jobs , it ’ s about filling jobs where there currently are no people available to do them ,” says Mr Shaw-Sutton , who is also a senior robotics technician at the University of Plymouth . “ For a while there have

been fewer people willing to go out into the fields and harvest fruit and vegetables ; this is an autonomous solution to that .”

And there are cost savings too . “ Even with the current cost of the unit , which we ’ re always trying to improve , it still works out cheaper than having someone employed on minimum wage - it can work for more hours , not needing lunch breaks or to sleep at night .”

Mr Shaw-Sutton and his co-founder Khaian Marsh both grew up on farms , so the RTU has been put through its paces in real life situations , including testing for soil compaction . “ There ’ s a small module with sensors which bolts onto the side of the RTU ; when it is pushed into the soil it can measure the force needed as well as moisture , and because it is on the RTU the data is processed there and then ,” says Mr Shaw-Sutton .

The unit comprises a large drive wheel , suspension and a computer system , held together by galvanised pipe – on which farmers can attach pretty much any implement . This includes conventional items such as a tow hitch , wheelbarrow

or grass cutter , but also more high-tech and new devices including soil probes , robotic harvesting arms or depth cameras for 3D crop rendering .

The component parts are all mass produced rather than specialist , which brings the costs down – for example the wheel ’ s brushless hub motor is from an electric bike . “ The unit is fully adjustable to any height and width ; some farms may have narrow paths , for example in fruit and vegetables , or it might need to go wider to get over tall crops ,” he explains .

The RTU works either by remote control or autonomously . “ We ’ re trying to make it as simple as possible . We currently have three options ; the first uses a remote control to drive the unit to a location ,

mark it as a point , drive to the next position and mark another point – then it will keep driving between those points .

“ The second uses an online map , which appears on a display with the current location . The operator can click where they want to send the unit and it will go there .”

The third , which is still under development , features full autonomous control . “ It is managed by drones . The positioning system on board the RTU is known as Real Time Kinematic ( RTK ) and allows for centimetre level precision from satellites . It is also the same system used by DJI Drones - the camera on board then gives a bird ’ s eye view , and their coordinate frames can be easily matched ,” explains Mr Shaw-Sutton .

“ The drone ’ s vision works on multispectral colour which features visible and infrared light , for example it may see the field as green and a patch of weeds as yellow – it can then send a coordinate to the RTU and instruct it over to spray off the patch of weeds .”

In terms of safety , there are emergency stop buttons on the unit and a remote kill switch . “ In autonomous mode that ’ s where all the sensors and cameras come into play , if it gets too close to anything it will stop .”

All data is processed locally , on board the RTU . “ That was a decision we made after speaking with farmers ; they wanted to know that only they had access to their data and it wasn ’ t going off to the cloud .”

The unit can carry several hundred kilos and is limited to run at up to 10mph , matching walking or running pace . It has the ability to tow or mount just about any equipment needed – making it extremely versatile and cost effective . “ It can be used for a range of things from crop monitoring to harvesting crops like cauliflowers ,” he adds .

It is powered by batteries , which last for 24 hours . “ Currently you just plug in to charge it , but we are considering having a docking station , because all of the power can be harvested from a single solar panel .”

Although the RTU is still in the testing phase , it is being offered commercially to researchers and they hope it will have enough functionality to offer to a wider market over the next year .