McHenry Forum - Crash Reconstruction & Simulation

On December 19, 2023, a final rule adopting the 11th Edition of the Manual on Uniform Traffic Control Devices for Streets and Highways—the MUTCD—was published in the Federal Register. The new MUTCD includes a number of updates to improve safety for pedestrians, bicyclists, and all road users. States...

I just realized i had promised to post up traditional closing speed calculation: Closing Speed Calculation Velocity Closing = A*Velocity1 - B*Velocity2 where Zeta = ATAN2(YCP2-YCP1,XCP2-XCP1) = space fixed angle between the Veh1 & Veh2 XCP1,XCP2 = Veh1 & Veh2 Space Fixed X coordinates YCP1,Y...

Drives me crazy when they talk of safety 'Recalls' of Telsa. Tesla issues massive recall of more than 2 million vehicles over autopilot safety concerns Tesla’s largest recall won’t fix Autopilot safety issues, experts say It even has topped the lists of many: The Biggest Car Recalls in History, Upda...

Question on another forum brought up this article SAE 2020-01-0880 , Quantifying Engine Braking for Various Common Street Motorcycles by Jansen, LeBlanc, Wilhelm, Shaw, et al. _________ ABSTRACT Motorcycle engine braking was measured in each forward gear for a cross-section of typical street motorcy...

Added some comments, links, etc to several of the posts
NOTE: since this is the 11th post, use the icon in lower right of the screen to go to other postings on this topic

Moved a link to the DRAFT copy of the article to the first post for folks who don't register...

Figure, comments and references added to prior posting from SAE 2016-01-1497 paper.

Another response was posted to the other forum i will summarize here and provide my answer: Q: Just to throw in an example the vehicle had speeds reported every 0.1 seconds. The collision was on wet roads, so realistically we are probably looking at values of mu no higher than 0.8 g. The last few re...

Look forward to evaluating that, if possible. First question: where did the speedometer data come from? a video? was this a full scale test? and/or why no EDR data? and how did you synch the speedometer with the ADR data? Second question/observation: location, location, location! In the picture it a...

When you mention ADR (Accident Data Recorder), i'm not sure what you mean? Do you mean the accelerations of the crash from airbag module data and then integrating to get the impact speed change and then when combined with the other vehicle (unless into a wall) get the impact velocity? Could you prov...