Two years ago, a group of engineers who had spent their careers on self-driving cars and trucks started Bedrock Robotics with a narrower goal: make an excavator dig by itself. Today, its autonomous excavators are doing paid work on real construction sites in the US, alongside human crews. Chief executive Boris Sofman, who previously led Waymo's self-driving truck programme, says the company has "proven that fully autonomous excavators can perform real work of value alongside the crews and workflows already in place on job sites".

This week investors put another $ 600 million, about R9.9 billion, behind that idea.

The founding team came almost entirely from autonomous driving. Sofman co-founded and ran Anki, the robotics company behind the Cozmo toy robot, before leading Waymo's trucking work. Chief technology officer Kevin Peterson and engineering vice president Ajay Gummalla are also Waymo veterans, and fellow co-founder Tom Eliaz came from software companies Segment and Twilio. Instead of building new machines, Bedrock makes a self-driving kit that can be fitted onto excavators and other worksite vehicles contractors already own.

In August, two years after it was founded, it moved beyond testing and pilots. Its excavators now work commercially at a water treatment facility in Nevada, on an earthworks site run by Champion Site Prep in Texas, and on a 1.2-million-cubic-yard project with Zachry Construction. Arizona contractor Haydon plans to use Bedrock-equipped machines on factories, water works, data centres and hospitals. The reason it chose excavators is a labour problem.

Bedrock says it takes five years or more to master operating one, and a US construction trade body estimates more than 40% of construction workers will retire within five years. The latest round values the company at $ 4.1 billion, about R67 billion, and takes its total funding to nearly $ 1 billion.

TechCrunch's Kirsten Korosec reported the funding and the move to commercial work, describing it as a speedy rise for a two-year-old company. TechCrunch's 2025 coverage of Bedrock's launch set out the founders' self-driving backgrounds. Modern Mining reported years ago that Kumba Iron Ore was the first iron ore miner in Africa to switch to autonomous drilling, controlled from a command centre at its Northern Cape mines.

The clever part is not the technology alone; it is where they pointed it. Self-driving cars have to cope with pedestrians, taxis and anything else a public road throws at them. A construction site is fenced, slower and highly repetitive, which makes it a much easier place to put years of self-driving know-how to work. And by selling a kit that fits on machines contractors already own, Bedrock avoided the cost of building excavators from scratch.

South Africa has a head start on parts of this. Kumba Iron Ore runs autonomous drill rigs at its Kolomela and Sishen mines, controlled from an office by former drill operators, and Midrand's Rosond has been building drill rigs it hopes to make fully autonomous. We have deep expertise in heavy machinery, plenty of it running on mines and building sites, and companies like HisWay Labs are already exporting tough industrial technology built here.

The local pitch would be different, though. In a country with high unemployment, a labour shortage is a weaker argument than it is in the US. The stronger case here is safety and productivity: moving operators off dangerous machines and into control rooms, the way Kumba did.

A South African team that built retrofit kits and remote control centres for that market would not need to wait for Bedrock to arrive.

You might also like our piece on electric trucks testing SA routes, the Jetson ONE flying machine, and BioInformatiCo's Leova.

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