Self-driving cars UK: how autonomous vehicle tech works and when we might see self-driving cars on the road

Department for Transport wants autonomous vehicles in UK roads within three years but how does the technology work and how soon will we see it on sale?

The Government has revealed ambitious new plans for the roll out of self-driving cars on the UK’s roads.

It intends to invest £100 million into research around autonomous vehicles to help pave the way for them to be introduced by 2025.

The latest annoucement from the Department for Transport claims that by 2025 legislation will allow fully driverless commercial vehicles to operate and by 2023 cars, vans and coaches equipped with what it calls “self-driving” abilities could be on sale in the UK.

It follows a previous annoucement that the the Highway Code would be updated in 2022 to include guidance on the use of “self-driving” cars, including when and where drivers will be able to delegate control of a vehicle to autonomous technology as well as who will be responsible if a self-driving vehicle is involved in a crash.

We’re still a long way from cars that don’t require a steering wheel
We’re still a long way from cars that don’t require a steering wheel
We’re still a long way from cars that don’t require a steering wheel

What are self-driving cars?

The Department for Transport (DfT) says the research funding and Highway Code guidance, along with legal changes made last year to recognise certain systems as “self-driving”, will put Britain at the forefront of autonomous driving adoption.

It also says it will allow some vehicles with self-driving features to operate on motorways in the next year.

But what does the DfT actually mean by self-driving cars?

The phrase conjures up images of futuristic pods with no steering wheel and passengers free to read, chat or watch TV while the car does the complicated business of getting from A to B. The reality, certainly for the foreseeable future, is a lot more boring and involves a lot more human input.

Discussions of self-driving or autonomous cars generally use a set of definitions created by the  Society of Automotive Engineers. These range from Level 0, which includes existing systems such as automatic emergency braking, to Level 5, where the “driver” is not responsible for controlling the car and won’t be asked to take over in any circumstances or conditions.

When the DfT talks about “self-driving” cars being on our roads by 2023 it is referring to vehicles equipped with Automated Lane Keeping Systems (ALKS), which fall under the SAE definition of Level 3 “traffic jam chauffeur”.

These use a combination of cameras and sensors - radar, lidar or ultrasonic - to monitor traffic conditions around the vehicle and match its behaviour to the conditions. They work in the same way as existing highway assist systems, controlling speed and steering to maintain a safe gap and lane position.

(Image: Society of Automotive Engineers)
(Image: Society of Automotive Engineers)
(Image: Society of Automotive Engineers)

The difference is that while current systems are recognised as “assistive” and require the driver to keep their hands on the steering wheel and be ready to resume control instantly, ALKS systems allow the operator to wholly delegate the driving task to the vehicle.

This means the driver can take their hands off the wheel and focus on non-driving tasks, including viewing non-driving related content on an infotainment screen. it also means that if the car is in a crash while the system is in operation, the driver will not be viewed as responsible and insurers or manufacturers will have to accept liability.

However, ALKS are still significantly limited. For a start, the Government proposes that they will only be able to be used on motorways and only up to 37mph.

Drivers will also still have to be able to take back control in a “timely manner” - previously quoted as 10 seconds - when prompted to do so, such as when approaching a motorway exit or if a sensor experiences a problem.

When will we see self-driving cars on Britain’s roads?

There is no simple answer to this.

When it changed the law last year, the Government claimed it would open the door for ALKS-equipped cars to be on our roads by late 2021. That didn’t happen.

Following the Highway Code announcement in April 2022, the DfT once again claimed “Britain’s first vehicles approved for self-driving could be ready for use later this year”. In its latest funding announcement in August 2022 it said ALKS-equipped cars could be on sale in the UK “within the year”.

However, there are currently no cars on sale in the UK that meet the widely accepted standards for Level 3 autonomy and very few anywhere in the world that qualify for such recognition.

Mercedes recently secured approval in Germany for the use of Level 3 systems in its new S-Class but only on certain pre-mapped sections of autobahn.

Rival BMW says it is working to have Level 3 autonomy available from launch in its new 7 Series, due out in late 2022.

Honda also achieved approval for Level 3 ALKS for the Legend EX in 2021. However, the approval is only valid in Japan and the car is not sold in Europe.

So outside the possibility of a handful of £100,000 luxury saloons, it’s unlikely we’ll see any “self-driving” cars on our roads in 2022 or 2023.

Nonetheless, the Government says it plans to have a full regulatory framework in place for the widespread deployment of ALKS technology by 2025. Furthermore, it says that by 2025 other vehicles, such as those used for public transport or delivery will not need anyone on board with a driving licence because “they would be able to drive themselves for the whole journey”.