Robots are beginning to offer farms the chance to automate time-consuming or labour-intensive jobs that employers are struggling to fill with manpower alone.

The technology can gather information, identify problems and harvest crops using an array of cameras and sensors to keep things on track.

We look at some of the latest robotic technology aimed at helping arable farmers to revolutionise their weed control.

See also: Is precision farming worth it? We ask two arable farmers

Deepfield Robotics Bonirob weeder

Public-funded research in Germany has gone commercial with the BoniRob, which was first seen as a small-scale prototype in the colours of one of the project partners, Amazone.

The Bosch Deepfield Robotics Bonirob weeder

However, the concept is being developed by new Bosch business, Deepfield Robotics, as a four-wheel drive, four-wheel steer vehicle with adjustable track width and optical or GPS guidance.

Deepfield researchers are trialling unassisted mechanical weed control, too – not by conventional hoeing or squirting a herbicide but by distinguishing between crop plants and weeds according to the shape of their leaves. Weeds are then rammed into the ground using an extending rod.

Mechanical weeders from Garford and Paulsen Engineering

Mechanical weeders that take a more refined approach are already available commercially, including the Robocrop InRow from Garford Farm Machinery and the Robovator from Paulsen Engineering in Denmark.

Both are designed to take out weeds between plants within a row, so are used mainly for sugar beet, salad and vegetable crops.

The Garford Robocrop In Row eRotor

The mechanisms use optical sensors to locate the plants, before pulling out the weeds while leaving the crop intact. The same technology is used on mechanical thinning devices and spot sprayers used for weed control and to deliver a fertiliser spray to individual plants.

Garford’s Robocrop InRow uses video imaging technology and has rotating hoes that take out weeds both within and between the rows.

The new eRotor version uses fast-response high-torque electric drives that accelerate each hoe in milliseconds from zero to full speed and back again to adjust for differences in plant spacing.

Garford says the increase in speed and precision this brings, together with an 80% reduction in power, results in up to 98% of the field surface being hoed at a rate of six plants per second with 1cm accuracy.

Neither of these weeders is fully robotic in the sense that they are still mounted on a conventional tractor. However, a small Robovator is used by vegetable breeder Rijk Zwaan on a semi-autonomous tracked vehicle for weed control in trial plots.

Carré Antis automated crop vehicle

Fully autonomous crop vehicles are currently in the development phase, including the Anatis four-wheel drive, four-wheel steer platform built by French tillage equipment manufacturer Carré and robotics firm Naio Technologies.

Carré Antis automated crop vehicle

Naio already manufactures the Oz self-guiding vehicle for inter-row cultivation and hoeing. However, the Anatis is larger and also provides decision-making support by processing crop images.

It records the presence of weeds, density and progress of the crop, luminosity, hygrometry and the temperature of the soil and the air.

Ladybird is another crop scouting vehicle being trialled by the Australian Centre for Field Robotics; it got its name because of the array of curved solar panels that enclose the techie bits.