Analysing collisions with vulnerable road users - Expert Witness & Investigations Services

We have developed specialist technology to assess and recreate collisions between vehicles and vulnerable road users (VRU) that has proven highly effective in the context of a court action.

When reviewing road traffic accidents (RTAs) it is critical to determine what a driver was able to see in relation to a VRU, especially when considering the VRU’s location and limitations of vision available to drivers of large goods vehicles (LGVs).

LGVs make up only 4% of road miles in London and yet figures from Transport for London (TfL) state they are involved in an exceptionally high number of incidents with VRUs, making up 23% of pedestrian and 50% of cyclist deaths in 2016 alone. This can be in part related to the restrictions to vision available to drivers of LGVs.

TRL’s team of independent experts utilise the latest methods to establish whether a driver involved in an incident had the opportunity to see the injured party and whether a collision was avoidable. This is particularly valuable in removing ambiguity from accounts of vision when presenting cases to the court.

Performing complete reconstructions of an incident along with 3D modelling and laser scanning vehicles and individual scenes, experts within the TRL Investigations team can assist in cases involving LGVs, buses, coaches, plant vehicles and cars to present the facts to a court in an understandable way.

Establishing how a collision occurred can be done in several ways. Traditional techniques involve the assessment of witness accounts, CCTV and physical evidence such as scuffs or damage to a road surface. Modern digital technologies including tachograph data also provide detailed information to investigators.

The increase in vehicles fitted with dash-cams can now also play a critical role in establishing a vehicle’s movement, where a VRU approached from and where they were struck. However, this footage can sometimes be subjective and give a misleading view as to what a driver was able to see during the incident.

Research completed at TRL has shown that minute variances in eye position can make a huge difference to the level of ground visibility drivers have available to them, particularly in large vehicles and LGVs.

Technology developed at TRL (the visibility assessment tool or ‘eyeball’) allows experts to recreate a driver’s eye position, removing prejudice from an assessment.

The TRL ‘eyeball’ consists of an adjustable arm, with a pivot point replicating neck movement, and an eyeball mount which mimics eye rotation by employing a laser pen embedded into the device to reproduce direct line of sight.

This assessment tool traces a driver’s direct and indirect vision and any objects that may cause obstruction, such as the steering wheel, dashboard, the vehicle’s frame or any windscreen or dashboard-mounted devices, allowing the areas of available vision to be marked out at ground level.

Using a 3D laser scanner, the vehicle, ground markers and eyeball position are all recorded, and a 3D model is created. Modelling driver vision and information from incident camera footage or other physical evidence enables highly accurate reconstruction of the position of a vehicle and a VRU in relation to each other. Combining this advanced assessment with physical evidence allows experts to determine exactly what was available to be seen prior to a collision, although it is important for this to be combined with a detailed reconstruction.

This process is invaluable when assisting the court in determining whether a party could or should have been seen prior to impact.

“Just because something is available to be seen, does not mean it will be if the driver is not looking in that direction at the critical time. TRL’s modelling process has proven to be highly effective in demonstrating the limitations to vision available to drivers in the context of a court action.”

TRL’s process can present information as a detailed series of images, within an expert report, or as a moving reconstruction using 3D modelling of a scene.

Experts within the TRL Investigations Team have a high level of technical competence and experience in this area. These analyses and modelling techniques, developed at TRL, have been accepted by the courts, and have proven to be highly valuable where court personnel have no first-hand knowledge or experience of the limitations of driver visibility.