Expert Witness Blog
In What is an Automobile “Black Box?,” Dr. Alexander Zhukov, M. Eng., Ph.D., and accident reconstruction expert witness writes:
Starting early-to-mid 90s recordable air bag modules (so called “black boxes”) have been installed in select GM vehicles. SDM, Sensing and Diagnostic Module, is the name given to air bag modules used in General Motors vehicles. Since 1998, recordable air bag modules have been installed in select Ford vehicles. RCM, Restraint Control Module, is the name given to air bag modules used in Ford vehicles.
A. Zhukov, Ph.D. & Associates is offering retrieval of data stored in the “black box” using Vetronix Crash Data Retrieval Tool (CDR Tool). The CDR Tool is capable of harvesting information from vehicle’s SDM and RCM. The device records data on a laptop PC which could later be transferred to any other device, if needed. Recorded data depends on vehicle make, model and year. The following data is typical of what is found on a newer GM vehicle:
Vehicle speed ( 5 seconds before impact )
Engine speed ( 5 seconds before impact )
Brake status ( 5 seconds before impact )
Throttle position ( 5 seconds before impact )
State of driver’s seat belt switch (On/Off)
Passenger’s air bag enabled or disabled state (On/Off)
SIR Warning Lamp status (On/Off)
Time from vehicle impact to air bag deployment
Ignition cycle count at event time
Ignition cycle count at investigation
Maximum delta-V for non-deployment event
delta-V vs. time for frontal air bag deployment event
Time from vehicle impact to time of maximum delta-V