A cut above: Scottish tech firm plans grass-cutting revolution with satellite guided robot mower

Scottish technology startup Kingdom Technologies is targeting a revolution in commercial grass-cutting with a new generation of innovative satellite-guided robot mowers. Jon Excell reports.

Kingdom's robot uses a suite of smart technologies to enable it to accurately, efficiently and safely cut large areas of grass with minimal human input.
Kingdom's robot uses a suite of smart technologies to enable it to accurately, efficiently and safely cut large areas of grass with minimal human input.

From the battlefield and the surgery, to the factory floor and the skies above our heads, few areas are off-limits to the increasingly advanced robotic systems that are transforming our world and reshaping our place in it. 

But on the West of Scotland Science park - a quiet, leafy campus just outside Glasgow - an altogether more bucolic version of the robot revolution is underway.

This is the home of engineering startup Kingdom Technologies, developer of an advanced new robot lawnmower that, it’s claimed, could help transform the highly lucrative and rapidly growing global lawn care market.

Founded in 2018, Kingdom has spent the past five years prototyping, developing and refining a system said to be more advanced than anything else on the market. Following a series of successful trials, the company is now poised to embark on a new push for investment that could see its technology deployed around the world on golf courses, playing fields, university campuses, and - in fact - anywhere with lots of grass that needs cutting.

At first glance, Kingdom’s technology doesn’t look that different to the kind of systems that you might find randomly trundling around a well-manicured suburban garden: a little chunkier and more rugged looking perhaps, but roughly the same shape and dimensions. Scratch beneath the surface however and it’s a very different beast:  bristling with a suite of smart technologies and onboard systems that enable it to accurately, efficiently and safely cut large areas of grass with minimal human input.

Kingdom CEO Joan Kangro explained that the rigorous demands of the commercial settings for which it’s designed, mean that the robot has to operate in a very different manner to existing systems, which have mainly been developed for the domestic market. “Current robotic lawnmowers aren’t suitable for commercial applications,” he said, “they don’t really know where they are and where they’ve been so they’re very inefficient. They might go over the same patch of grass 20 times a day, and they’re not able to cut very big areas operating like that.”

Kingdom’s system, however, operates in a more human way: mowing in an organised, pre-planned and more efficient manner. This means that whilst the mower travels at similar speeds to existing systems (around 0.5m/ s) it’s able to cover around ten times more ground. Indeed, over the course of a day,  it’s claimed a single mower could cover an area roughly equivalent to a large football field.

What’s more, whilst existing off-the shelf mowers require the installation of a boundary cable (a perimeter cable that marks the edge of the robot’s domain) Kingdom’s robot is able to operate off the leash, using an advanced satellite navigation system and a host of safety features to carefully control its movement and dispense with the need for a physical barrier.  

According to Kingdom’s head of mechanical engineering Tony Day, these capabilities demand a far greater level of technological sophistication than is found in existing systems.  “Changing this methodology opens up a whole new area,” he said.  “You can’t use your old technology anymore. In order to plan a route and go round and cut and say ‘I’ve definitely cut this’ you need to put in a whole different level of technology. If you open up one of our robots and compare it to one of these traditional ones. theirs is pretty empty. There’s not a lot in there (just a few sensors, some drive motors and a cutting assembly) whereas ours is packed with stuff!”

When it senses the battery is beginning to run low the robot autonomously docks itself in the charging station

Amongst all this “stuff” is a centimetre accurate positioning system based on dGNSS technology and Odometry; a special algorithm that’s used to plan optimum cutting paths; and a combination of LIDAR and vision systems that the mower uses to detect and avoid obstacles (existing systems detect obstacles by bumping into them which would be impractical from a safety point of view for larger applications). Interestingly, these safety sensors are also used to further improve the robot’s efficiency by adjusting its speed depending on the thickness of the grass. “It perceives areas where there is more and less dense grass,” said Day. “If it’s less dense grass, the mower can go faster and ensure the cutting quality but if it’s more dense grass the robot slows down”.
This is all underpinned by a Kingdom Technologies developed web platform that’s used to plot and plan cutting operations using satellite imagery. 

The final key element is the charging station. During operation, the robot follows the cutting instructions defined by the customer and, when it senses the battery is beginning to run out of charge - it autonomously navigates to the station, where it automatically docks and charges itself. 

Like all elements of the technology, this charging station has been designed to withstand the rigours of daily commercial use, and a key priority for Kingdom throughout the development process has been identifying technologies and components that are as close to maintenance free as possible.

This has required close collaboration with a number of key suppliers, including -  perhaps most notably - plastic bearing specialist igus UK, which has supplied lubrication free bearings for a number of different areas. 

One of these applications is in the cutting height adjustment mechanism, a critical application requiring extremely tight tolerances. “The precision tolerances available in the igus bearings allowed us to design a cutting deck that has less than 1mm deviation in height across its width, giving a uniform, quality cut to our lawns,” said Day. 

igus parts are also used in the lift sensor mechanism, which is used to detect if the mower is lifted manually, triggering the mower to go into a safe mode. Here, piston rings made of igus’ iglidur material are used to give a dry running, maintenance-free and reliable action in a very small package space. Finally, igus linear bearings are used in the opening and closing mechanism on the charging station door, another element of the system that again has been carefully designed to withstand everything the weather can throw at it.

Igus sales engineer Rob Day (left) with Kingdom's head of mechanical engineering Tony Day (right)

Since its launch in 2018, Kingdom has attracted £3m in awards and grants, developed a series of ever more sophisticated prototypes and carried out three years of pilot operations. It now has 20 robots in the field and continues to finesse the design and tweak the technology based on feedback from these customers. The Plan is to have 140 robots deployed by the end of next year (2024) and to be generating £1m of revenue. This, hopes Kangro, will pave the way for increased private investment  in the technology. 

Rather than become a mass-manufacturer and seller of devices, the company’s ambition centres around a pay-per service model where customers pay a monthly fee to Kingdom. According to Kangro, this novel approach makes the service more affordable for the customer, as the fees will typically be less than having the lawn cut by a regular contractor. 

Ultimately, Kangro believes the system could take a significant chunk of the growing $32 bn commercial lawn cutting industry, an area in which robotic systems have so far had a relatively small  impact.

Whilst the current focus is firmly on getting this initial product offering right (for instance, the route-mapping web platform is still being refined) Kangro and the team are also considering a range of future opportunities including the development of new type of mower optimised to cut fairways on golf-courses. According to Kangro this would require a cylinder cutter rather than the blades used on the current version. 

Even further into the future, the team has a vision for the lawnmower equivalent of a ride sharing model – whereby urban users with an unruly lawn could simply log onto an app and summon up one of Kingdom’s robots.