banner ad
Experts Logo

articles

Pedestrians' Injuries & Effect of Automobile's Front-End Design

By: Dr. Mukul Verma
Tel: (248) 892-0020
Email Dr. Verma

View Profile on Experts.com.

Every year, there are approximately 6000 fatalities (6227 in the year 2018) and many more serious injuries to pedestrians and bicyclists from vehicles in the USA. More recent data1 show that these numbers have increased by 45% since 2009. These trends have varied over the years but injuries and fatalities to pedestrians and cyclists from automobiles remain a serious issue.

Pedestrian Accident

In order to address this and to reduce these injuries and fatalities, it is necessary to (1) reduce the probability of such accidents, and (2) reduce the severity of the impacts when these accidents happen. The first step requires that appropriate traffic rules and infrastructures be implemented to increase the separation between vehicular traffic and other road users. The second step is to investigate designing vehicles' front ends to reduce the severity of impacts when they happen. This is discussed here.

The Law

Currently, there is no law in the USA governing the structural design of road vehicles for reducing pedestrians' injuries. In the early 80s, an Advanced Notice of Proposed Rulemaking (ANPRM) was issued by the National Highway Traffic Safety Administration (NHTSA) but was cancelled. However, several other countries (Japan, European countries, etc.) have had such laws in place (as described in www.unece.org/trans/main/ wp29/wp29wgs/wp29gen/ wp29registry/gtr9.html) which mandate that certain tests be conducted and that vehicles meet specified performance criteria in these tests.

These tests represent (a) head form of an adult and of a child, striking designated parts of the vehicle's upper front; and (b) adult leg forms impacting lower front surfaces. In order to comply with these requirements, the vehicle manufacturers have to implement designs which: (a) control the structural stiffness of the components in the impact zones (hoods, fenders, headlights, etc.); and/or (b) provide adequate 'crush space' underneath the surfaces struck by the impactors. It is also possible that, instead of providing crush space, the manufacturers may meet the law by installing 'active systems' to 'pop up' the hood by a certain amount when impact on the hood is detected, thus creating a crush space when needed. The other available option is to install 'hood airbags', also deployed when an impact is detected by onboard sensors, thus reducing impact-induced forces on the pedestrian's head.

Figure 1

Accident Statistics: Pedestrian Fatalities and Incapacitating Injuries

Distribution with Age:

According to a study published3 some years ago, the distribution of the number of vehicle crashes with cyclists and pedestrians shows a 'bimodal' trend - (1) sharper peak for children and young adults, and (2) distributed peaks for older adult population.

Chart 2

A similar analysis of the number of fatalities and incapacitating injuries among pedestrians showed similar trends. This implies that, when studying countermeasures for injury reduction, both these population groups must be taken into account.

Chart 1

Research on the Effects of Vehicle Design on Pedestrian Injuries

It is known that the front-end (and other) structural components of an automobile are designed to meet multiple requirements for protecting its occupants in various crashes and adding the requirements for pedestrians' protection may appear to be a conflict. However, the crash energies in pedestrian and cyclist impacts are much lower than those involved in protecting the vehicle's occupants in accidents. Thus, it may be possible to decouple the 'structure design domain' for these two categories. Generally, the parts likely to affect a pedestrian's impact severity are the outer surfaces (such as the hood, fenders, pillars, frame around the windshield etc.) and components (such as antenna, headlights, etc).

. . .Continue to read rest of article (PDF).


Dr. Mukul Verma, is a well-known expert in Automobile Safety and Crashworthiness, Vehicle Structures, Product Design, and Statistical Analyses of Traffic Trends and Regulations. He has worked in many engineering and management positions at a major automobile manufacturer including assignments in R&D, vehicle design, analysis and testing and engineering program management.

©Copyright - All Rights Reserved

DO NOT REPRODUCE WITHOUT WRITTEN PERMISSION BY AUTHOR.

Related articles

neinstein-photo.jpg

2/22/2018· Automotive - Vehicular

Safety Compromises, Part 4: Speeding

By: Ned Einstein

Speeding would seem like the most obvious safety compromise. Speeding would seem like the most natural remedy to a schedule too tight, and the most obvious way to pick up more passengers, increase system capacity and maximize revenue: Just drive faster.

neinstein-photo.jpg

7/14/2017· Automotive - Vehicular

Autonomous and Inevitable, Part 6: The Transition to Complete Autonomy

By: Ned Einstein

When an asteroid strikes a planet, things tend to change quickly. Most other changes occur gradually, even while a small handful are occasionally more significant. These latter changes are sometimes referred to as "paradigm shifts," largely because they affect so many things around them, and cause such dramatic changes in the things they affect directly.

neinstein-photo.jpg

11/3/2004· Automotive - Vehicular

Defensive Non-Driving

By: Ned Einstein

Since driving a 20- or 25-ton motorcoach is touted as so being difficult, it is only fair to ask why so much carnage, and so many law suits, occur apart from collisions. In particular, the number of incidents occurring at or near stops seems largely disproportionate to the perceived simplicity of handling things when the bus or coach is stationary

;
Experts.com-No broker Movie Ad
Unicourt Logo Button

Follow us

linkedin logo youtube logo rss feed logo