An Israeli-American start-up has developed a retrofit kit that allows small tractors to work entirely autonomously, principally for spraying permanent crops such as vines and orchards.

Given Bluewhite’s focus is on sub-100hp machines with little in the way of electronics, much of the conversion involves attaching mechanical actuators that work the controls much like a human operative.

So, unlike sophisticated alternatives from the likes of US outfit Sabanto, which tap into the tractor’s canbus system to work the controls, Bluewhite uses linkages to physically push the brake pedals and pto lever, and a little motor to turn the steering wheel.

See also: UK made kit converts any tractor to RTK autosteer for £3k

© MAG/Oliver Mark

The brains for this are tucked inside a box in the right-hand footwell, with a simple on-off switch to disengage the driverless mode.

Handily, none of the extra gizmos interfere with the manual controls, so an operator can hop on and off without making any alterations.

© MAG/Oliver Mark

Safety systems

Obstacle detection is provided by a lidar sensor and camera, which sit atop a safety bumper on the front of the tractor.

These features mean it can operate safely, typically at speeds of 3-8kph, should the guidance signal drop off.

The system runs through Bluewhite’s Compass web interface, which owners can use to view live video feeds while the machine works.

The hardware and installation costs US$35,000 (£27,000), after which buyers must cough up US$30,000 (£23,000) for an annual subscription.

The company has a ruck of machines working down the west coast of the US, where their roles are not only saving labour but, more pertinently, keeping staff safe from potentially harmful plant-protection products.

© MAG/Oliver Mark