Pedestrian safety through vehicle design

These involve redesigning the bumper, hood (bonnet), windshield and pillar to be energy absorbing (softer) without compromising the structural integrity of the car.

Vehicle designers usually focus on understanding the car-pedestrian interaction, which is characterized by the following sequence of events: the vehicle bumper first contacts the lower limbs of the pedestrian, the leading edge of the hood hits the upper thigh or pelvis, and the head and upper torso are struck by the top surface of the hood and/or windshield.

[2] Most pedestrian deaths occur due to the traumatic brain injury resulting from the hard impact of the head against the stiff hood or windshield.

The hood of most vehicles is usually fabricated from sheet metal, which is a compliant energy absorbing structure which poses a comparatively small threat.

[4] Some models, like the Citroën C6 and Jaguar XK feature a novel pop-up bonnet design, which adds 6.5 cm (2.5", C6) extra clearance over the engine block if the bumper senses a hit.

Computer simulations and experiments with cadavers show that when cars have lower bumpers, the thigh and leg rotate together causing the knee to bend less and thus reducing the likelihood of ligament injuries.

[5] An early example can be found on trams in the form of a lifeguard which prevents pedestrians from being caught between the wheels of the leading bogie should they be hit.

One of a series of safety research vehicles produced by British Leyland in the 1970s including a pedestrian-friendly bonnet
Omniview technology gives the impression of looking down on the space around the car, and allows the driver to see people and objects in the immediate vicinity before moving off.
The sequence of events in a car-pedestrian crash
While the lower limb is the most commonly injured body region, most pedestrian fatalities are caused by head injuries. [3]
Land Rover Discovery Sport showing the pedestrian airbag (in gray) at the rear of the hood
A protective shield in front of a Helsinki tram, ca 1975. When a person hits the detector (yellow arrow), a shield (red arrow) launches to prevent the person from going under the wheels.