Prof Rod Kimber, director of science and engineering at the Transport Research Laboratory, is the man who oversees the transport technology that helps keep the UK on the road. Here, he talks to Niall Firth.
With its acres and chrome and its minimalist whitewashed walls, the Bracknell HQ of the Transport
Research Laboratory (TRL) looks more like a suitable venue for a slick media outfit than a venerable engineering institution. However, since its creation over 70 years ago, the ever-modern TRL has been at the cutting edge of transport- related technology.
Today, TRL is responsible for some 600–700 projects a year, developing technology for everything from road pricing systems to vehicle impact testing. The diverse nature of TRL’s research is reflected in the variety of its 550 employees, whose expertise ranges from engineering to psychology.
Prof Rod Kimber, TRL’s director of science and engineering, is the man charged with overseeing this extensive portfolio. Kimber is an influential voice in the UK transport industry who, in addition to his duties at TRL, is also technical director of the AA Foundation for Road Safety Research and a visiting professor at Imperial College.
He explained that much of the laboratory’s current research is focused on technology for reducing the environmental impact of traffic and cutting noise pollution. TRL has been particularly heavily involved in the development of low-noise road surfaces. The Highways Agency has targeted 2010 as the date by which 90 per cent of the country’s roads will have low-noise surfaces.
One of TRL’s recent successes in this area is TRITON, a system currently being used by the HA to monitor the noise produced by motorway surfaces. The technology consists of a wheel attached to the bottom of a seven-tonne lorry. This wheel is contained within an anechoic chamber and can be raised or lowered by the driver.
Extremely sensitive, rugged microphones are used to monitor the sound from the road’s surface. These microphones also function as differential sensors which monitor the variations in sound compared with each other while using sophisticated noise-reduction electronics to filter out the noise from other vehicles on the road.
Using TRITON, a ‘sound footprint’ of every metre of road on the trunk road system can be produced, and areas where work needs to be done to reduce noise pollution pinpointed. Kimber said: ‘Around 90 per cent of people hear traffic noise and something like two thirds are bothered by it, so finding ways of reducing noise from traffic is an important research area for us.’
TRL’s research has also helped debunk a number of traffic-related myths over the years. One of the most important of these was a breakthrough in the understanding of road surface degradation. ‘Traditionally, people assumed roads cracked from the bottom up and that by the time the cracks reach the top, the road needed completely replacing,’ said Kimber.
‘We researched this in great detail and discovered that cracks start at the top and propagate downward.’
This was a significant breakthrough that had huge implications for road manufacture and maintenance. If a road surface could be accurately and regularly monitored, a motorway could be made to last almost indefinitely. A layer could be added to the surface or, if it was particularly bad, the surface could be planed down to stop further cracking. The ‘long-life road’ was born.
TRL also developed The Highways Agency Road Research System (HARRIS), a laser scanning device, also attached to the bottom of a truck and used to monitor the road surface. The system scans the road surface 64,000 times a second and provides a highly accurate 3D map of the road’s surface and texture.
Another key area for TRL is road safety, and the organisation co-operates with the major car manufacturers in testing advanced car safety devices.
According to Kimber, there has been a massive increase in occupant car safety systems following the introduction of NCAP testing in 1995. However, protecting pedestrians in collisions is still low on average car manufacturers’ list of priorities.
‘Occupant safety is a big issue these days, with the car-buying public being influenced by the results of testing and the star ratings manufacturers receive,‘ he said. ‘Unfortunately, the results of pedestrian collision testing don’t seem to have as much of an influence on car-buyers so the manufacturers don’t worry so much about the subject.’
Kimber’s team works at the forefront of research into intelligent safety systems for cars, some of which are already finding their way into top-of-the-range models. Recently, it has worked on an intelligent system in which the vehicle detects an imminent collision and fires the airbags fractionally early.
‘Obviously, these systems have to be extremely accurate as we don’t want the car thinking there’s about to be an accident when there isn’t,’ said Kimber.
His team has also developed and evaluated a seatbelt fitted with a small pyrotechnic device in the tensioner. This deploys in the early moments of an impact, when deceleration passes a certain threshold. The pyrotechnic device fires a charge that wrenches the seatbelt back hard, pinning the occupant into his or her seat.
But clearly it is preferable to avoid a crash altogether and much of TRL’s work in car safety is manufacturer-led primary safety technology, ranging from advanced ABS braking systems to an electronic stability control system. These systems, which Kimber terms ‘semi-intelligent’, sense when a wheel is about to slip and activate the brakes separately
in the appropriate wheel while adjusting engine power to minimise loss of control.
Another system Kimber believes will be on the market soon is steering intervention technology, where the car takes over the steering if it senses the driver is losing control.
Looking further ahead, he envisages cars that send a distress signal to one another moments before a crash. This will detail the vehicle’s mass, speed and structure, allowing both cars to make minor adjustments to minimise the effects of the impending crash.
Though TRL’s work focuses on transport technologies, and roads in particular, it also covers other applications.
For instance, its Soundprint system has been used for acoustic monitoring in bridges.
Multi-strand cable tensioners in bridges are embedded in reinforced concrete and are inaccessible without hacking the bridge open, causing transport chaos for weeks while they are fixed. The cables are made of a large number of filaments which are wound together and break over a period of time.
An embedded Soundprint sensor listens out for the tell-tale sound of a filament’s final moments. ‘When a cable parts it gives off a signature ‘ping’ sound,’ said Kimber. ‘If you can hear the pings, you can say: “Yes, in 2004/05, six strands pinged all together in a certain bridge”, and you can accurately model the state of that bridge and judge when it needs mending.’
The Soundprint sensor uses sophisticated software to pick out the faintest ping from the background noises of a busy bridge. It cancels out all other noises and gives an accurate model of the bridge’s structure.
This can be used in combination with another TRL development which fits probes into a bridge to detect corrosion in steel.
TRL’s most recent technology is a 3D laser scanner used in the forensic reconstruction of traffic accidents. This can be deployedwithin 10 minutes of an accident and scan the scene in detail, providing a 3Ddatabase including skidmarks, sightlines and distribution of debris.Details are then fed into a computer simulation package which provides a reconstruction of the incident that can be viewed from any angle.
TRL is also working on developing technologies for road pricing on motorways, but Kimber was understandably coy about going into details at such an early stage.
He did, however, reveal his team is looking into ways to spot vehicles attempting to outwit pricing systems by shadowing other vehicles or switching lanes directly below detectors.
‘It’s early days yet,’ he said, ‘but there’s going to be a lot of very interesting technology coming out of the road pricing issue.’