Driving without a driver: The five levels of autonomy
To ensure various levels of autonomy, autonomous driving has been grouped into five levels:
- Level 1: Common driver assistance systems such as automatic cruise control.
- Level 2: Semi-automated systems such as lane assistants, parking aids or emergency braking.
- Level 3: A high degree of automation, such as independent overtaking manoeuvres and other autonomous decisions, based on the current traffic situation. The intervention of a driver is only needed if prompted by the system.
- Level 4: All standard driving tasks are carried out completely autonomously. Drivers can intervene on request, but their presence is not necessary.
- Level 5: The vehicle handles even the most complex driving situations autonomously and drivers no longer have the possibility of intervening. These vehicles are also allowed to drive without passengers.
The current state of play: successful tests
The technology is becoming increasingly sophisticated: the latest tests of autonomous HGVs in the US have been promising. Drivers, who are still required on board while on public roads for legal reasons, no longer needed to intervene. The vehicles took full responsibility instead – including for their trailers, which weighed up to 36 tonnes. This means that level 4 of autonomous driving has been achieved.
When stage 5 can be implemented – and whether this is even desirable in practice – remains to be seen. As of 2023, autonomous driving without the physical presence of a driver is only permitted in defined and approved operating areas, one example being shuttle vehicles on company or trade fair grounds. In order to put fully autonomous HGVs on the road, the technology must be fully functional and 100% mature.
The US is more open to autonomous vehicles than the UK
Acceptance of this technology in the UK is still limited – at least as far as autonomous cars are concerned. Although attitudes are slowly changing, a 2023 poll carried out by the Institution of Mechanical Engineers indicated that 70% of British drivers would feel uncomfortable travelling in a fully autonomous vehicle with no human control. And just less than half of respondents said they would feel comfortable driving an autonomous vehicle, but only if it could also be operated like a conventional vehicle.
In the US, the willingness to approve autonomous HGVs is currently more widespread. The first autonomous trucks are expected to be on the road from 2025, but will likely still be controlled remotely in emergency situations. The UK has not yet set a target for when freight transport by road could take place without a driver. In addition, there’s a question mark over whether truly driverless truck traffic will be implemented at all in the foreseeable future, since drivers are not only responsible for driving the vehicle, but are also in charge of the freight.
Pros and cons of autonomous HGVs
The advantages of autonomous HGVs are obvious: on motorways, autonomous lorries can transport goods from point A to B in convoys more efficiently and without driver intervention. Even if a driver is still needed for the first and last miles, driving and rest breaks would become obsolete as they could rest on the motorway, significantly reducing travel time. Reliable systems also make fewer mistakes and drive more carefully than humans, so the number of accidents can also be expected to decrease.
Without a driver, staff costs would also be lower. The current staffing situation in the transport industry is extremely strained, and many logistics companies find it difficult to recruit drivers at all. In 2022, the Road Haulage Association reported a shortage of some 100,000 HGV drivers in the UK – Brexit and COVID-19 exacerbated a pre-existing retention issue. Autonomous HGVs could, at least in the medium term, compensate for the problem of driver shortages.
However, the whole endeavour has one major drawback: the technology required to ensure safe autonomous operation is highly complex. If the systems do not work as intended, serious accidents can occur when there is no supervising driver to intervene. Additionally, the high degree of network integration can also make them vulnerable to hacker attacks.