President’s Spotlight—Engineering & Applied Sciences


During the year, we have been presenting presidential spotlights from the Academy sections to highlight the latest significant research or improvements within its discipline. Examples include cutting-edge technology, standards, or methods that improve the practice. Alternatively, they may show a historical account/timeline of the discipline’s use of innovative technology or research. These are presented to inform all members of how each discipline is responding to the challenges of a modern forensic science world—our theme for the year. This featured submission is from the Engineering & Applied Sciences Section.


Sources: Mark I. Marpet, PhD, PE; Sarah V. Hainsworth, PhD; John Nixon, MBA; Laura L. Liptai, PhD

The Forensic Engineering Spectrum

The forensic engineer investigates building and infrastructure failures; violations of building codes and standards; product failures; vehicle, air, and rail accidents; explosions, floods, and environmental contamination; criminal acts, and the mechanics of human injuries by acts of  stabbing and other attacks.

The engineer’s  analysis is used in a court of law as part of a legal action and is often a factor in the re-design and improvement of products, buildings, and structures. For example, satellite imagery can be used for indicating soil settlements at a macroscopic level, which can be a major cause of structural failures. It was a factor contributing to the collapse of the 12-story condo tower that crumbled to the ground on June 24, 2021, in Surfside, Florida.

Collapse of 12-Story Condo in Surfside, Florida

 

In 1895, mechanical engineer and physicist Wilhelm Conrad Röntgen produced and detected X-rays or Röntgen rays. His use in 1896 of this electromagnetic radiation between gamma rays and the ultraviolet was the first forensic engineering use of X-rays and earned him the inaugural Nobel Prize in Physics in 1901.


Forensic Engineering in Action

The Engineering & Applied Sciences (E&AS) Section uses scientific principles and engineering to answer questions of technical importance to the legal community. For example, the question of how fast a car was traveling is important to determine whether a driver is responsible for or contributed to causing an accident. Forensic engineering work is directed at both civil and criminal law but with a preponderance in civil cases.

One area of forensic engineering is architectural and is the evaluation of buildings and sites required to accommodate the disabilities of persons with mobility, dexterity, vision, hearing and cognition impairments. It often regards compliance with the federal Americans with Disabilities Act (ADA). A member of our E&AS Section served for 31 years on the American National Standards Institute’s A117 Committee, whose design standards are the basis for those of the ADA. Since 1990, forensic architects have been instrumental in evaluating construction for accessibility and informing the court on compliance with the ADA. They have been major contributors to making America accessible to all its citizens for over 31 years. Forensic architects are also broadly and deeply involved in research such as that of human biomechanics and vehicular crashes.

Biomechanics Research

Vehicle Crash Research

Another aspect of forensic architectural research regards “slip resistance” of walkway surfaces. Existing standards say that a floor must be “slip resistant,” without specifying what that means. Members of our Engineering Section are using tribometry research to establish a scientific definition of slip resistance.

Portable Inclinable Articulated-Strut Tribometer


Forensic Engineering on the Cutting Edge

The most critical area of firearm safety is the trigger mechanism. Before the advent of advanced electronics, computers, and software, trigger performance was evaluated using laborious manual techniques.

Toward the end of the 20th century electro-mechanical test instruments were introduced; comprising a motorized arm and load cell system to record the force applied to a trigger over small travel increments. Software calculates the energy required to actuate the trigger mechanism (the area under the trigger force-travel plot).

This new instrumentation has enabled forensic specialists to examine firearms for performance, post manufacture modifications, and defects, often without the need for firearm disassembly, thereby avoiding spoliation issues.

Glock Pistol Ready to be Tested Using Electro-Mechanical Instrument

 

Instrument Output Examples

Note that while the single action Dan Wesson requires 1.5 times the peak force to discharge, the double action Beretta 92 requires 16 times more effort to discharge (illustrated by the red/black area versus the green/black area).

 

Engineering & Applied Sciences Creating Worldwide Outreach

Two members of our American Academy of Forensic Sciences (Academy), Dr. Laura Liptai of the Engineering & Applied Sciences Section and Secretary of the Academy and Mr. Barry Fisher of the Criminology Section and Past Academy President provided the development of an initial project for the International Affairs Committee (IAC) called the Global Collaboration of Forensic Scientists (GCFS). They also co-chaired the International Criminal Investigative Training Assistance Program presentation, “Advanced Topics in Digital Forensics” (November ’21).

In June, in Tashkent, Uzbekistan, Dr. Liptai and Mr. Fisher co-chaired a virtual session on “Forensic Science Yesterday and Today” for The United Nations Office of Drugs and Crime during Uzbekistan’s Celebration of the 70th Anniversary of its Ministry of Justice’s National Forensic Science Centre.