Last reviewed 13 February 2018

The Department for Transport has recently consulted on some proposed changes to the Construction and Use (C&U) Regulations and the Highway Code with a view to amending both so that some existing technology may be used without risk of contravening the current law and guidance. This is a further step towards making fully autonomous vehicles legally permissible. Richard Smith explains why these changes are necessary and the technology involved, with a look ahead to the future for automation.

The story so far

Since 2015, the Government has been preparing the way for the eventual deployment of fully autonomous vehicles with a graduated programme of consultation and legislation. In the initial stage, it was determined that testing of advanced vehicle technology (AVT) on the roads in the UK was already possible and so the second stage focused on tackling the regulatory issues preventing available or near-available AVT and advanced driver assistance systems (ADAS) from being used legally. Now the third stage, in a consultation which has just finished, is proposing the detail of the necessary amendments to the C&U Regulations and the Highway Code so that these features can be used legally.

Available technology

A good deal of what might be called “precursor technology” is already available and being used as separate applications. This technology is called Level 1 and 2 automation, where the driver is still required to keep eyes on the road at all times and hands on the wheel except in specific cases.

Park assist

Park assist can manoeuvre a vehicle into a parallel or perpendicular parking space that is of an appropriate size. Sensors measure potential parking spaces as the vehicle is driven past and when it detects a suitable one it alerts the driver. When the driver acknowledges the alert, the system takes over control of the steering and guides the vehicle into the space with the driver still having control of the speed.

Lane departure warning

This system “sees” the white lines in the centre of the road and between lanes with forward-facing cameras and provides a visual, audible or vibration warning when the line is about to be crossed unless the appropriate indicator is in use.

Lane keep assist

This goes one step further than lane departure warning by not only alerting the driver to the problem but steering the vehicle back into the lane unless the driver overrides it.

Emergency autonomous braking

Again using cameras, the system detects a potential collision with a vehicle in front and provides a warning to the driver to brake. If the warning is not heeded, the brakes will be applied automatically.

Adaptive cruise control

Cruise control is a very long-standing technology for maintaining a constant speed without the driver pressing the accelerator. The adaptive aspect means that when the controlled vehicle comes up behind a slower one, the speed is automatically reduced without driver intervention and the vehicle maintains a set distance behind the one in front, automatically accelerating and braking as its speed changes.

Near to market technology

Two further applications of Level 2 automation are defined as “near to market” and these are the subject of the consultation because their use is either illegal or contrary to the advice in the Highway Code at the moment.

One of these, remote control parking, is in fact already available on some cars and has been demonstrated in television advertisements for Mercedes cars. Using this technology, the vehicle can be parked in a bay and extracted from the bay without the driver on board but operating the system from outside the car using a smartphone application. This allows a vehicle to be parked much closer to the next one since the doors do not need to be opened after it is parked.

The second technology, motorway assist, combines existing systems of adaptive cruise control, autonomous emergency braking and lane keep assist to give autonomous control over both lateral and longitudinal position in a specific case (motorway).

Changes to the C&U Regulations

Regulation 110 of the C&U Regulations currently prohibits the use of a device which performs an interactive communication function while driving. This is the regulation that makes using a hand-held mobile phone illegal but could also be interpreted to include using a remote control device for parking. To remove any uncertainty, it is therefore proposed to include a further specific exemption to the three already in the regulation and this will permit the use of a hand-held device in order to carry out remote control parking. It will be a requirement that the command is activated not more than six metres from the vehicle and that continuous activation is needed (ie a “dead-man’s switch”).

Three other regulations are relevant to remote control parking and motorway assist.

  1. Regulation 104 requires “that a driver must always be in a position to have full control of the vehicle and full view of the road and traffic ahead”.

  2. Regulation 107 requires “that a driver must switch off the engine when not attending a vehicle”.

  3. Regulation 109 states: “the driver must not be in a position to see (directly or by reflection) a television set or similar screen showing moving images, in order to prevent driver distraction”.

All of these have been the subject of an earlier consultation during which it was concluded that Regulation 109 should not be amended and while there is a good case for amending Regulations 104 and 107, that is not proposed at this stage.

Changes to the Highway Code

The Highway Code is not legally enforceable in itself but the advice contained in it is based on various pieces of legislation and some of the rules are legal requirements. It does also have the status of an Approved Code of Practice and as such, failure to comply with the advice might be taken as evidence of, for example, careless driving.

  • Rule 149 reiterates the C&U Regulation 110 on using mobile phones.

  • Rule 150 deals with driver distraction from in-vehicle systems.

  • Rule 160 states that drivers should keep both hands on the wheel where possible.

  • Rule 239 concerns parking and the driver’s behaviour when doing so.

Amendments to all these rules are proposed giving specific guidance for using ADAS and emphasising that even when doing so the driver is still responsible, must use the systems only in accordance with the manufacturer’s instructions and continue to exercise full control of the vehicle.

Towards full autonomy

These proposals establish very limited, partially automated operation of single vehicles. The next stage (not included in this consultation) involves permitting vehicles to be linked together under certain circumstances, that is the “platooning” of vehicles on a motorway with the driver of the lead vehicle effectively controlling the whole convoy, although the drivers in the following vehicles must remain alert with hands available and eyes on the road at all times. Successful platooning was first demonstrated on the VW test track many years ago and in 2016, the Netherlands Government issued a challenge that saw vehicles from six truck manufacturers (DAF, Daimler, Iveco, MAN, Scania and Volvo) travelling in platoons on public roads across Europe.

The next stage of automation (Level 3) is where the vehicle is conditionally automated, that is the driver may be able to take hands off the controls and eyes off the road temporarily while being ready to resume control in response to a system demand. At Levels 4 (highly automated) and 5 (fully automated), the vehicle is completely capable of operation on its own and the driver does not need to remain ready to take over if the system demands. The difference between these stages is that at Level 4, the driver could take over when the system is not in use, while at Level 5 that will not be possible since no driver controls are fitted.

These highest levels of automation will require a step change in technology. The cameras currently in use currently require a strong contrast between road features and the background and may easily be obscured by dirt. Lane assist systems will not work if there are no lateral road markings, or if the markings are worn or obscured by leaves, dirt, snow or standing water. Automated braking systems may be defeated when the sun shines on the lens or there is poor contrast between an obstacle and the sky. A driver in the USA was killed when his car, running in a partially automated mode, drove under a white painted trailer that was turning across the road because the camera could not discern the side of the trailer from the light background.

Full automation will require additional light detection and ranging (LiDAR) sensors that use lasers, in addition to simple vision cameras, much more accurate mapping of roads and considerable development of software, including the ability for vehicles to talk to each other, before it can be deployed outside test conditions. All of this technology will be expensive and a long beta testing period will be required to iron out all the foreseen complications, never mind the “unknown unknowns” that will inevitably crop up. Deployment is unlikely to come much before the cut-off date for the sale of petrol and diesel vehicles.