Intelligent Speed Adaptation (ISA)

Introduction

1. The Minister for Transport asked the Motorists' Forum to consider the final report of a four year research project, carried out on DETR's behalf by Leeds University and the Motor Industry Research Association, into External Vehicle Speed Control (EVSC), otherwise known as Intelligent Speed Adaptation (ISA). The Forum was asked to consider the findings of the report, the issues it raises and the acceptability of ISA from the motorists' standpoint.

2. This task was delegated to the Forum's Rights and Responsibilities Working Group, chaired by Sir Christopher Foster, which met on 6 December 2000. The group comprised members from the Association of British Insurers, Environmental Transport Association, Gwent Consultancy, Institute of Advanced Motorists, PACTS, RAC Foundation, RAC Motoring Services, Retail Motor Industry Federation, Society of Motor Manufacturers and Traders and University College London. The AA had submitted comments prior to the meeting. Representatives from DETR also attended in an advisory capacity.

3. The group benefited from a helpful discussion paper and presentation from DETR. Some members of the group had also driven a vehicle fitted with ISA technology. The group did not examine the technical aspects of the project but instead concentrated their examinations on the acceptability of controlling vehicle speed in the way envisaged by ISA from the motorists' standpoint.

4. The Working Group's recommendations were subsequently submitted to the Forum Plenary on 22 January. The following report has been endorsed by Plenary members although there are objections from the Society of Motor Manufacturers & Traders and the RAC Foundation. These reservations are attached as appendices to the report.

Principle of ISA

5. Essentially, ISA is a means of restricting the maximum speed of a vehicle to the limit in force on any given road, utilising global positioning satellite technology. That technology could be used either to advise the driver of the speed limit in force and/or when they were exceeding it, and/or intervene to limit the maximum speed of the vehicle.

6. The principles behind the design of ISA were meant to ensure that:

i) the driver would retain overall control of the vehicle under all circumstances;

ii) the speed limit could be exceeded in particular circumstances; and,

iii) the ISA system should not be obtrusive within the vehicle.

Benefits Identified from Research

7. Research had indicated that a mandatory ISA scheme could lead to a reduction of 36% in road traffic (injury) accidents and 59% in fatal accidents. There would also be benefits in terms of lower fuel consumption (up to 8%) and more effective road traffic enforcement.

8. The research had also indicated increased journey times of 2.5%, equating to an additional 1.5 minutes per hour. However, journey times would be more predictable and the consensus is that congestion would not increase. Evidence from the M25 variable speed limit initiative had shown an improvement in traffic flows by controlling vehicle speed in this way.

Cost of System

9. The cost of a basic system is currently estimated at between £1,200 and £2,400 per vehicle. That cost is expected to decrease to between £250 and £400 by 2010. Nevertheless, Plenary members were concerned about the cost of the introduction of such a system.

Views of the Group

10. The Group strongly emphasised that although adherence to the maximum speed limit was important, there were circumstances when it was right to drive at an appropriate speed below the limit. It was poor driving, often below the speed limit, and not necessarily excessive front-line speed that killed. Merely driving below the speed limit would not necessarily make a driver safer. Drivers must retain responsibility for driving safely and also needed to guard against adopting bad habits which poor use of ISA might encourage. ISA should interact with safe and responsible driving.

11. The Group felt that the predicted casualty reductions were impressive. If they were accurate, it would be difficult to oppose ISA in principle. However, there was a long way to go and further options should also be considered. Any such system that was introduced must have total integrity. To that end, equipment reliability was an important factor.

12. Some additional concerns were raised. ISA might not cover all types of road and where it did operate, motorists would inevitably drive as fast as possible up to the maximum speed limit. Also, ISA did not appear to include motorcycles. ISA would only be practicable if all vehicles had the technology installed, which could be a serious problem at the beginning.

13. In response to these concerns, the Group noted that DETR intended to conduct a separate research project to assess driver behaviour and agreed that curbing inappropriate speed was of paramount importance. One of the features of the ISA technology was that temporary lower speeds could be brought into effect, such as outside schools, where there were roadworks and in adverse weather.

14. Among possible additional benefits, the Group felt that the introduction of ISA would force local authorities to compile accurate speed limit data on each road within their boundaries. This, in turn, would encourage authorities to review the appropriateness of currently imposed local speed limits and to introduce changes where necessary.

15. It emerged from discussion that the SMMT was currently opposed to any technical external control of a vehicle that removed a driver's ability to drive at the correct speed for the type of road and prevailing conditions, even with an override system in place. The industry supported the principle of additional driver support systems but did not believe at this stage that mandatory ISA was the way forward. The potential casualty savings identified in the research report were thought to be exaggerated. A voluntary system would, however, be more acceptable. Other options, incorporating some of the benefits of ISA, should be considered. In its current proposed mandatory form, it was felt that ISA would create danger on the road and not reduce it. The RAC Foundation also had reservations on account of practicalities, cost and interference with motorists' freedom.

16. The Group noted that DETR had currently no plans to implement ISA. We were also advised that should a decision be taken in the future to introduce the system, the first step would be to equip all new vehicles. DETR considered that ultimately, most benefit would be derived from a mandatory system - though to gauge public acceptability there might be a need, initially, for a voluntary scheme with an override facility. Whichever option was chosen, the driver should retain control of the vehicle and be able to reduce speed below the maximum speed limit.

17. There was concern that some in the media could present ISA in a negative light without fully considering the research findings. This might influence motorists' perception of the value of the scheme. Others expressed concern about promoting mandatory ISA at an early stage. The Group felt that the Government needed to market the benefits vary carefully and be able to offer convincing answers to these concerns, backed-up by sound research.

Summary of Views/Recommendations

18. The consensus view was that it was clear that there was a long way to go before the Group could come out in favour of ISA. Nevertheless, the cost-benefit ratio as presently calculated on the basis of the known facts is highly positive, although this might depend upon all roads being subject to control. It was hard to imagine any other measure offering equivalent safety gains. ISA therefore warranted further consideration.

19. The retention of driver responsibility was considered very important. The Group felt that the more responsibility was taken away from the driver, the greater there was a possibility that drivers would rely on that technology to drive safely without taking other relevant factors and potential hazards into consideration. Trials should focus on this area.

20. The question of whether a voluntary, mandatory and/or an override system were best should also be thoroughly researched, as should the effect of ISA on driver behaviour. Although the Group could not endorse ISA at this time, there was broad agreement - with the exception of the SMMT and the RAC Foundation (who both had reservations) - that members would be prepared to accept mandatory fitment of ISA in principle provided all potential problems could be overcome.

21. Concerns remained about:

i) the limited benefit of ISA at lower speeds;

ii) more work being necessary to see how ISA worked in different sorts of traffic;

iii) transitional arrangements - these would clearly need to be very carefully considered;

iv) asset management - this would be a matter of particular concern for local authorities; and,

v) the need for further cost/benefit analysis to be undertaken, particularly as the cost estimates are refined.

22. The Group sought clarification on whether these concerns were being addressed. DETR explained that information on the cost benefit of ISA had already been included in the final report and that they were about to go out to tender on a new project looking in more detail at the long term behavioural aspects of ISA. We were grateful for the offer by DETR to circulate the tender documents for comment.

23. Finally, the Group was pleased to note that DETR confirmed that they were co-ordinating the ISA research and trials with those being undertaken in Sweden and the Netherlands. We welcome the continuation of this.

Appendix: Intelligent Speed Adaptation: The RAC Foundation View

Following the presentation at the Motorists' Forum meeting on 6th December 2000, it was agreed that the RAC Foundation would set out more fully our concerns about the concept of external vehicle speed limiters [ESVL], or intelligent speed adaptation [ISA].

On the behalf of the RAC Foundation, I am glad of the opportunity to set out our views and will do so as succinctly as possible to avoid abusing the privilege and because the views will be discussed by the RAC Foundation for Motoring Public Policy Committee on 29th January 2001.

The RAC Foundation for Motoring has consistently supported the development and introduction of measures with the proven potential to reduce the risk of collision and injury to road users and will continue so to do.

At first glance, the concept of external speed limiters operated intelligently to adapt the speed of vehicles to speed limits and adverse weather conditions seems unexceptional. However the RAC Foundation has a number of concerns about the underlying principles and practical consequences of such a scheme.

Excess / Inappropriate Speed

External speed limiters operate on the basis of posted speed limits recognized by the GPS satellite operating system, be they permanent, or temporary. As such they embody the potential to reduce the significant number of collisions and casualties of which excess speed is a direct causal factor.

However speed limiters have no potential whatsoever to tackle the equally significant problem of inappropriate speed, that is speed which although not in excess of the speed limit, is too fast for the prevailing driver, road, traffic, weather or vehicle conditions and is therefore prima facie dangerous. The dangers of inappropriate speed are dearly demonstrated by statistical research, including Oliver Carsten's own study of accident causation in Leeds during the early 1990s.

However the concentration of ISA on the danger of excess speed, may well encourage a belief on the part of the average motorist that if excess speed is dangerous, any speed within the limit is safe.

Discretion

The exercise of discretion is a skill which must be learned and constantly practiced, or it will wither. The RAC Foundation believes that the less opportunity afforded to drivers to exercise discretion, the less they are likely to exercise discretion, even where it is allowed. We are concerned that drivers will come to rely upon the ISA system to control the speed of their vehicle, rather than hazard perception and sound judgement. We note from the supporting research a tendency for 'close following' or 'tailgating' on the part drivers using the ISA enabled vehicle. Which suggests that ISA may simply replace one potentially hazardous activity with other equally hazardous conduct.

"Convoys", "Platooning" and ''Tailgating"

At present the speed of different vehicles along inter-urban and rural roads varies considerably. Many vehicles exceed the speed limit, some by a small margin, others by a potentially dangerous level. Many do not exceed the speed limit at all. This speed differential produces two beneficial effects. Drivers tend to concentrate on vehicles around them to avoid conflict with faster or slower traffic and the speed differential creates gaps in the traffic flow, even on busy motorways such as the M25.

An external speed limiter would create a potentially hazardous situation whereby large groups of vehicles would travel together with no speed separation at the speed limit. The dangers of this phenomenon sometimes known as "platooning" are well known in the USA where the rigorously enforced national highway speed limit of 55 mph led to large groups of vehicles travelling together, often with inadequate distance between individual vehicles and contributed to major highway pileups.

ISA and non-ISA vehicles

The RAC believes that the potential safety benefits of ISA equipped vehicles will be at least partially offset by the potential dangers arising from the mixture of ISA and non-ISA enabled vehicles in what is already a potentially lethal cocktail of traffic.

The collision potential between new ISA enabled vehicles slowing for the ubiquitous temporary speed limits on our patched and mended inter-urban road system and their unlimited older counterparts is all too obvious. Any driver who has tried to slow for a temporary speed limit in front of heavy goods vehicle will recognise the dangers posed.

Potential Benefits

Nevertheless, the RAC Foundation recognises that external control of vehicle speed brings with it a number of potential benefits.

It will almost certainly lead to a reduction in the number and severity of collisions and casualties related to excess speed. However, the RAC Foundation believes that the very promising casualty reduction estimates accompanying the presentation rely upon the author's assumptions and a highly selective interpretation and extrapolation of causation data and casualty statistics and should be rigorously tested, before they are considered as a reasonable basis for objective assessment of the costs and benefits of the scheme.

Once a significant proportion of the vehicle parc is ISA enabled [assumed to be 60% by 2019] speed cameras and traffic calming measures will become unnecessary. Thereafter realistic speed limits could be set in the knowledge that they will not be exceeded and areas of conflict between otherwise law abiding motorists, local authorities and the Police will be removed.

Appendix: The Society of Motor Manufacturers and Traders Limited

Letter to Sir Christopher Foster of 16 January 2001

Motorists' Forum - Rights and Responsibilities Working Party - External Speed Control

Following the presentation by Neil Bowerman at the last meeting of the Working Party on the subject of External Vehicle Speed Control, you asked me to write to you outlining the motor industry's objectives to these proposals. I trust that you will recognise that the Industry has a track record of introducing innovative vehicle systems and features to improve the safety of vehicle occupants, and other road users, in response to both Government and consumer demand.

It is widely accepted that 95% of road accidents are caused by human error, despite all the innovations and safety improvements provided. The Industry view is that ultimately road safety is the responsibility of the road user, and particularly the vehicle driver.

There is a view currently being proposed by 'Road Safety Campaigners' that 'speed kills'. While not trying to change the law of physics, we believe that 'speed' per se is not the issue, but rather the choice of the appropriate speed for the conditions. Motorways and segregated high-speed traffic routes are generally much safer than other classes of road, both urban and non urban.

As part of the improved reliability of modern motor vehicles, the motor industry spends a large amount of resource to ensure that increasing electronically complex vehicles are immune from interference by outside electromagnetic (radio) interference. Imposing an external control on the vehicle goes directly against this legislatively required effort.

Having set that general background, we believe that the proposals being developed for DETR are wrong in a number of specific instances as follows:

1. Imposing an 'official' limit on the vehicle's speed outside the driver's control may in certain circumstances prove more dangerous than leaving the driver in total control. We believe there is a strong probability that many drivers would adopt an 'auto pilot' mindset and would not be alert, because they would be falsely confident that if any risky situation occurs, the vehicle would take over and manage the situation by slowing the vehicle. This has dangerous implications for all sections of road, not just the controlled ones.

2. The liability for any accident occurring while a vehicle was in a 'controlled' state could be argued to rest with the local authority who had taken control of the vehicle's speed away from the driver. Such accidents are totally foreseeable, for example if a driver was unable safely and quickly to overtake a cyclist, or was part way through a high speed overtaking maneuver when the speed of his vehicle was suddenly restricted.

3. If, when the restriction was lifted, the drivers foot was hard on the accelerator (quite likely as the driver waited for de-restriction to occur), and the vehicle was in a low gear (again quite likely as the vehicle may not run properly in a high gear at low speed), a dangerous situation would occur as the power suddenly became available, especially on a wet road.

4. There is no such thing as tamper-proof, black box technology. By using roadside transmitters set to zero, criminal elements could use the equipment to stop cars for theft or any other purpose. Separately we have no doubt 'disabling kits' would soon be marketed to overcome the technology.

5. As the recent case monitoring a High Court Settlement when a driver obeying the speed limit knocked down a child in a residential area demonstrated, driving at the approved local speed limit may not be appropriate. Factors affecting this include the local geography and circumstances, weather conditions, and even the time of day. Current local authority guidance and resources are not sufficient to regulate every circumstance, and the driver must retain the responsibility for deciding the speed. We are of the firm belief that application of such speed controls will lead to a reduced level of driver responsibility and attention.

6. The Industry recognises that speed, or more precisely the (rate of) change of speed, is one of the factors affecting the severity of injuries resulting from road accidents. Other factors include the headway (i.e. gap) between vehicles in a traffic stream, and it is for this reason the Industry is developing systems that will help motorists' drive more safely. These systems, which are selectable by the driver, and can be over-ridden by the driver, include such systems as Automotive Cruise Control, lame keeping support, and collision warning systems. We believe that the application of such systems will provide a much safer environment in a much wider range of circumstances.

7. If External Vehicle Speed Control is proposed as a form of speed enforcement, then recent infrastructure development are really proving it unnecessary. Strategic location of speed cameras is already providing an effective deterrent, as can be seen for example on the A45 around Coventry, the Al north of Newcastle and on the M25 variable speed limit section.

8. There is evidence to suggest that the introduction of speed limiters on Heavy Goods Vehicles has lead to an increase in accidents, due to attention loss by HGV drivers.

Members of the Working Party may have gained the impression that with External Vehicle Speed Control, all equipped vehicles will be limited to the same speed. You should be aware that the current legislation governing speedometers contains a tolerance allowance to allow for - (a) mechanical tolerances through the direction, and (b) the effect of wear on vehicle tyres. Two identical vehicles, travelling at an indicated 60 mph may in fact have a speed difference of 8 mph because of this. There are no proposals to contain this, and indeed nor would it be practical to do so.

The MIRA Leeds University study has produced some impressive claims for reductions in fatalities. We remain sceptical as to the validity of these claims, and note the highly publicised 59% reduction is dependent on the availability of a dynamic, mandatory system.

Finally, we note that WP29, the Global Forum for International Vehicle Regulations with UN ECE has been having informal discussions on a French proposal to introduce requirements for speed limiter devices. As part of these discussions, proposals from the UK to enable external vehicle speed control without driver acceptance action have been rejected.

Members of the Working Group should remember that the UK would have to notify the European Commission of any proposal to unilaterally mandate the use of speed limiter devices, and that any legislation is likely to be required on a European rather than National basis.

EUR ING. R A WATSON
Head of Technical Department