13/04/2026
https://www.facebook.com/share/p/18WTpQBGn8/
Richard Ruth is one of the OGs of EDR analysis. He's written lots of papers on them, and looked at more of their data than perhaps anyone I know. When he says something about EDRs, I try to listen. He offered two comments on my post a while back about the term "Maximum SDM Recorded Velocity Change (mph)" which may appear on some older reports. I'm reposting them here, as many folks don't follow the comment section, and the information is worth noting. EDR reports may look like plain language, but there's often more to it under the surface. Thanks for the pointers, Rick! Peace. -W
1. Side airbags started in 1999-ish but the side satellite sensors in the B and C pillars were running at 4K, the data could not be streamed at that rate to the central control modules, the decision to deploy had to made at the satellites and all the ACM knew was if it was told to deploy. There was no lateral sensor in the ACM because it was not used in the decision process in those days.
2. When GM Gen 2 (99-04ish) said "Max Delta V" yes it did mean "Max Longitudinal Delta V" and that was because ONLY longitudinal Delta V was recorded, there was no lateral Delta V recorded. But 𝗚𝗠 𝗚𝗲𝗻 𝟯 (𝟮𝟬𝟬𝟱-𝟮𝟬𝟬𝟵𝗶𝘀𝗵) is the EXCEPTION - the System Status still had "Max Delta V" with no identification, but it had both X and Y Delta V sensors and the Data Limitations defined Max Delta V as "the square root of x-squared plus y-squared", meaning the total Delta V. After that the labels were clear in the System Status.
