Perception – Reaction – Braking

Hugh Borbidge, BSME, Director of Engineering Animations



We, as vehicle operators, avoid collisions every day. We stop for red lights, brake when a car cuts us off, and slow down if there are children playing close to the roadway. In these avoidance situations, there are three components: Perception, reaction and braking.
Perception is when we first notice a hazard or the need to react to something. Reaction is the time taken to respond to what was perceived. A typical daytime perception/reaction time for a vehicle operator is about 1.5 seconds, meaning that, when you notice a hazard you keep traveling at the same speed for 1.5 seconds before you start applying the brakes. Braking is the minimum time it takes to bring the vehicle to a stop. Every bit of time in this series of events equates to a certain distance traveled. For example: Continue reading “Perception – Reaction – Braking”

Applying Photography, Video, 3D and other Expertise to Forensic Analysis

3D Camera Matching in Engineering Animations

Laurence R. Penn, 3D Animations/Technical Assistant ::::
At DJS Associates, we are often called upon to analyze surveillance videos to make a region of interest easier to identify or to re-create the recorded scenario entirely. What may seem like a simple task actually relies on thorough review and consideration of many factors within the footage. Often these factors are subtle and only an experienced technician can identify the clues provided in the images.
With 3D camera matching, evidence and surveillance imagery can be digitally processed and spatially analyzed to reconstruct a scene. Continue reading “Applying Photography, Video, 3D and other Expertise to Forensic Analysis”

DJS Engineering Animations

Engineering Animation

Laurence R. Penn, 3D Modeler and Animations Expert ::::
When it comes to creating compelling, scientifically-based Computer-Generated Images (CGI), V-Ray from ChaosGroup is now the render engine of choice utilized by DJS Associates’ 3D Engineering Animation Department. V-Ray is a physics based texturing and rendering platform used by many top studios around the world. In fact, V-Ray received an award at the 2017 Academy Awards from the Academy’s Scientific and Technical Awards Committee for its role in bringing realistic CGI to the big screen. Continue reading “DJS Engineering Animations”

Recreating Vehicle Movements: Update from our Engineering Animation Department

1 Engineering Animation Vehicle Path

Hugh Borbidge, BSME, Director of Engineering Animations ::::
There are many ways to re-create vehicle movement in a 3D computer environment. Some methods are better than others. We will talk about 3 different methods; simple, rigged, and physics based.
Engineering Animation Vehicle PathThe simple method is the easiest and fastest method as the name implies. The vehicle is treated as one object. The chassis and wheels do not move independent of each other. They all move as a unit. In the image above, the red lines represent the tire paths. You can see that the front and rear tires follow the same path even as the vehicle makes a turn. This is not scientifically accurate but can sometimes be useful for a “down and dirty” review for things like basic spatial relationships. Continue reading “Recreating Vehicle Movements: Update from our Engineering Animation Department”

The “Art” of Engineering Animations

3D Animation

Hugh Borbidge, Computer Animation Engineer ::::
Item 101- Accurately Moving a Vehicle on the Computer Screen
3D engineers that do forensic work often times feel a little jealous when we watch a Pixar movie. In Pixar movies vehicles tend to move in such an artistic way. They are seen bopping to music, bending around corners, and even talking. Many times the creative teams behind these movies ignore the laws of physics. But that’s ok, they don’t have to. Accurate engineering animations, on the other hand, do have to abide by the laws of physics. Engineering animations can be (and typically are) highly scrutinized and the slightest inaccuracy can render them such that they are not accepted by the courts. Continue reading “The “Art” of Engineering Animations”