Category : Uncategorized

Pedestrian Collision Animation

Hugh Borbidge, BSME, Director of Engineering Animations

This animation demonstrates a pedestrian v. vehicle collision that occurred when the vehicle continued driving through a red light. An engineering analysis was conducted by DJS Collision Reconstruction and Biomechanical Engineers. An accurate, to scale 3D engineering animation was created as a demonstrative for trial. The result shows a pedestrian vault, which is a movement similar to that of a football being punted. This movement involves many factors, including vehicle speed, angle of impact, ground coefficient of friction, vehicle point of rest (if they stop), and the pedestrian point of rest. These factors can be used to calculate the vehicle speed at the time of impact.



Hugh Borbidge, BSME, Director of Engineering Animations with DJS Associates, Inc., can be reached via email at or via phone at 215-659-2010.

October is National Pedestrian Safety Month


Robert T. Lynch, P.E., Principal Collision Reconstruction Engineer

Three out of every four pedestrian fatalities occur at night. This fall, as the days get shorter and the nights get longer, the risks for pedestrians increase. This year, NHTSA has launched the first National Pedestrian Safety Month with the goal of increasing awareness about pedestrian safety, reminding both drivers and pedestrians that staying safe is a shared responsibility.

continue reading

Don’t Look Behind Door #1

Lt. Col. Bryan J. Smith, P.E., Construction Site Safety / Slip, Trip and Fall

Case Description/Summary: An older gentleman took his wheelchair-bound wife to see her doctor. Upon arrival, the gentleman found that the front entranceway to the doctor’s office was not wheelchair accessible. He left his wife outside and inquired within to find the handicapped accessible entryway. The gentleman was told to take his wife around to the rear of the building, where the accessible entrance was located. After proceeding to the rear of the building, the gentleman found an entrance in the middle of the building. The entrance did not have a wheelchair ramp to the door, though it was only a little lift needed to get the wheelchair over the 1.25-inch-tall threshold. The door swing was into the building. The gentleman pushed it open with his back as he backed his wife into the entrance and over the threshold. As soon as he cleared the doorway, the gentleman began falling down the basement stairs, located directly behind the door. Unfortunately, his wife and her wheelchair also came down the stairs, landing on top of him. The wife died just a few days later from injuries received during this incident, while he sustained serious physical injuries, as well as emotional trauma.

continue reading

Which Impact Caused Plaintiff’s Injuries?

Robert J. Nobilini, Ph.D., Biomechanical Engineer

Case Synopsis: Plaintiff was the operator of a vehicle that was initially impacted on the front driver’s side corner by a vehicle prior to being struck in the rear by a second vehicle. Plaintiff incurred a left shoulder supraspinatus tendon tear during the subject incident. It was requested that the dynamics of the two impacts be examined to determine which impact caused the plaintiff’s left shoulder injury.

continue reading

Rideshare Barriers – Added Safety or Additional Hazard?

John R. Yannaccone, P.E., Senior Mechanical Engineer

2020 has been a year full of changes. Virtual learning, Zoom meetings, and wearing masks are now daily rituals experienced in our world. In the transportation industry, even more changes are being made in the name of social distancing; however, some changes might negatively affect the safety of ride-share passengers. In an effort to separate the driver’s space from the passenger’s space in cars, some drivers have added aftermarket barriers, while others have resorted to homemade walls between the front and rear seats of their vehicles. While these barriers are being added to keep people healthy, how might they affect the safety of the occupants should there be a crash?

continue reading

Lemon Law

R. Scott King, BSME, CFEI, Principal Automotive/Mechanical Engineer

At both the state and federal levels, consumer protection laws generally provide opportunities for relief to vehicle owners adversely impacted by manufacturing defects or “non-conformities” that cannot be resolved within a predetermined time, vehicle mileage or number of repair attempts. Like many litigated cases, matters arising within the so-called “lemon law” framework can be aided by expert analysis, reporting, and testimony; however, an expert can also be used in an advisory role to objectively evaluate a case’s strengths and weaknesses, and equip the retaining party with information to facilitate an efficient resolution. So it was in a recent case.

continue reading
1 2 3 17