Active measures to stop VRU accidents

Protecting Vulnerable Road Users with PreView side object detection technology

Given the catastrophic results of an incident involving a large vehicle versus a Vulnerable Road User such as a bicyclist, pedestrian, or motorcyclist, collisions and the difficulties of protecting these VRUs, the simplest solution would be to prohibit these forms of transportation from traveling on the streets and roads designed for vehicles. This solution, while it may seem like a practical answer, is in fact impractical, socially unacceptable, and counterproductive to the overall advancement of society

We Know Where Most Accidents Happen

Across the European Union, collisions with VRUs account for almost 50 percent of European vehicle-related injuries and fatalities. Of those, 28 percent are the result of incidents involving medium or large trucks. The numbers remain stubbornly constant de - spite significant efforts by truck manufacturers and after-market suppliers to improve vehicle design, safety devices and systems. One reason the numbers aren’t improving is that the work to improve truck safety is being offset by counter - vailing environmental efforts to reduce vehicle traffic and the problems it causes. The net result is more pedestrians, bicyclists, and motorcyclists sharing increasingly limited space with vehicles on roadways. Data gathered from collisions involving VRUs and large trucks points overwhelmingly to the passenger side of these vehicles — the largest blind spot and the most common impact point for VRU-involved collisions — have a substantial need for what is known as abbiegeassistenten (side turn assist) in Germany

Passive Solutions Are of Limited Use

European truck makers have adopted various forms of abbiegeassistenten modifications. Some truck OEMs have lowered the truck operator’s position in the cab in hopes of giving them a better view of their surroundings and installed more windshield glass. Others have attached more mirrors and cameras to improve the operators’ view around these large vehicles. These solutions share one common limitation: They are all passive. To avoid collisions with VRUs or other vehicles, operators must continuously shift their gaze from windshield to mirror to camera monitor and back again. This constant swivel cre - ates a great deal of mental stress for the operator and reduces the chances that the operator will be looking at the right device at the right time to pre - vent a collision. Furthermore, mirrors can provide a distorted image that can also misrepresent the proximity of an object to the vehicle.

Then, there is the matter of the simple geometry of mirrors as a truck turns. When a truck is aligned with its trailer, the mirrors provide a static view along the sides of the truck. As soon as the truck begins to turn, however, the mirrors continue to show a view directly behind the cab. The view from these static mirrors and cameras shows less and less of the side of the trailer and more of the front. As the cab continues to turn ahead of the trailer body, the operator’s viewPreView Side Defender II becomes increasingly restricted until there is virtually no view along the side of the trailer. Which means in the middle of a turn—especially in a crowded urban area—the operator has virtually no idea what is happening along the length of the trailer. Such blind corners are a recipe for disaster but, short of developing mirrors that rotate to maintain a rear view, it remains unavoidable.

Guiding Operator Attention

Unlike mirrors and cameras, radar does not depend on direct line of sight. Mounted on the side of a heavy-duty vehicle, for example, PRECO’s PreView Side Defender^® II sensors emit radar waves in an approximate 150-degree, semi-rectangular pattern along the side of the trailer. When the radar waves make contact with an object such as a VRU in close proximity to the side of the vehicle, the waves bounce back to the sensor. The sensor filters out stationary objects and alerts the operator to those that are in motion – such as VRUs. Also unlike mirrors and cameras, this radar-based system is “active.” The operator does not need to split his or her attention between windshield, mirrors, and camera monitors to become aware of approaching VRUs. The Side Defender II, in effect, actively tells the operator when to pay attention. As part of the Side Defender^® II system, the PreView^® v2 in-cab display equips operators with more intuitive audible and visual alerts while offering installers more flexibility and time savings. For retrofit applications, the new display can provide a GPS based vehicle speed message, while OEMs and bodybuilders can connect the display directly to the vehicle CAN-bus for vehicle speed information.