Page 1 of 1

What is RICSAC?

Posted: Sun Jun 21, 2009 9:49 pm
by MSI
Research performed in the 1970's to “locate, review, decipher and place in useable form available experimental data on the structural crush properties of automobiles, and on the spinout trajectories produced by measured collision conditions” [1] revealed significant limitations in the available documentation of vehicle crush information and trajectory spinout information. As a result, an initial test matrix of 12 full-scale crash tests was performed in 1978 which became known as the Research Input for Computer Simulation of Automobile Collisions (RICSAC) crash tests [2].
  • For each of the RICSAC tests, a minimum of 13 accelerometers were mounted on-board each vehicle to record acceleration components at six to seven stations. At three locations triaxial (XYZ) packages were installed ("hard mounted") to provide coverage between the front and rear of the vehicle. The front steer angles were measured on each vehicle by a linear stroke potentiometer attached to the vehicle steering linkage. The time history of the change in vehicle yaw, pitch and roll angles and yaw rate were recorded by two-degree-of-freedom, free gyroscopes and a rate gyro.

    For vehicle trajectory measurement, high-speed motion picture cameras were located overhead with supporting cameras at eye level height. Also, vehicle trajectory marker systems were designed and fabricated by Calspan to spray high pressure colored water trails (using very small amounts of liquid to avoid any effects of the water on the roadway coefficient) from several locations on each of the vehicles.

    Plots of the full-scale test acceleration time-histories were generated by a computer program which also integrated the acceleration time histories (using a combination of Simpson's and Newton's 3/8 methods) in order to obtain velocity time history along each of the vehicle's three axes. For most of the reported results, the ?V values reported for the vehicle CG were based on data collected by a Firewall mounted triaxial (XYZ) accelerometer.
    The time of approximate separation reported in [3] was based on observation of the time histories of the acceleration. The time of separation was defined as "the point at which both of the involved vehicles' accelerations re-approached 0 g's". The authors of [3] noted that "the separation point was not always obvious in collisions in which the two vehicles spun out together".

    The components of the vehicle's change in velocity (DeltaV) were computed in [3] "by subtracting the initial velocity at impact from the velocity at the time of separation" . The procedure was done for the X and Y velocity components separately.

    The authors of [3] acknowledged that the "value for the separation velocity was contaminated by the effects of rotation of the vehicles between impact and separation". The problem was attributed to the post processing integration software used for the tests which was primarily set up to integrate acceleration data for frontal collisions with barriers and therefore did not account for the rotation of the vehicle (the data reduction software assumed a constant direction cosine matrix). Errors which may occur in data collected from an accelerometer not at the center of gravity include the effects of rotation which are dependent on the magnitude of the offset of the accelerometer from the CG and the magnitudes of the vehicle's angular velocity and acceleration.

    A summary of the RICSAC tests was created in 1980 by Smith & Noga in Examples of Staged Collisions in Accident Reconstruction [4]

    In our 1997 SAE paper RICSAC-97 - A Reevaluation of the Reference Set of Full Scale Crash Tests [5] we presented a detailed review and decipherment in usable form of the original 12 crash tests that were performed within the RICSAC program. A new method of analyzing accelerometer data from arbitrary sensor positions, on the basis of discrete measures of the vehicle responses rather than complete time-histories, is defined. A discussion of previous research which included reference to the RICSAC test results as a measure of the validity of reconstruction computer programs is included.
  • 1) "Research Input for Computer Simulation of Automobile Collisions", McHenry, R.R., Lynch, J.P., Segal, D.J., Calspan Report ZQ-6057-V-1, Contract DOT-HS-7-01511, Jun 1977
    2) "Research Input for Computer Simulation of Automobile Colliisions - Staged Collisions, Vol II & Vol III", Shoemaker, N.E., Calspan Report ZQ-6057-V-4 & V-5, Contract DOT-HS-7-01511, December 1978
    3) "Research Input for Computer Simulation of Automobile Collisions - Volume IV - Staged Collision Reconstructions", Jones, I.S., Baum, A.S., Calspan Report ZQ-6057-V-6, Contract DOT-HS-7-01511, December 1978
    4) "Examples of Staged Collisions in Accident Reconstruction", Smith & Noga
    5) RICSAC-97 - A Reevaluation of the Reference Set of Full Scale Crash Tests, McHenry & McHenry, SAE paper 970961

Re: What is RICSAC?

Posted: Mon Aug 31, 2009 4:05 pm
by brian
Additional reports related to full scale tests perfromed under the RICSAC:
3 Additional Tests (RICSAC 13-15) performed at Texas transportation Institute:
  • Improvement of Accident Simulation Model
    James, Hayes, Ross & Whittington
    Contracts DOT-HS-5-01262 & DOT-HS-7-01656
Additional tests by Dynamic Sceince:
  • Countermeasures for Side Impact - Shaw, Knight, Rodack
    Contract DOT-HS-9-02177
    PB85 170017/AS - Final Report
    PB85 170025/AS - Vol II Appendices A-D
    PB85 176295/AS - Vol III, Appendices E-I

Re: What is RICSAC?

Posted: Mon Dec 12, 2011 5:21 pm
by brian
Dec 12, 2011: Q: Are you going to scan the RICSAC reports? In particular can i get a better scan of the photos for RICSAC tests 3,4 & 5? Some of the page numbers are difficult to read but it looks like pages 9-10 thru 9-16, 10-11 thru 10-16 and 11-11 thru 11-17?

A: Yes soon we hope to scan the entire reports and post them up. In the meantime, below are links to the photos of the RICSAC Tests 1-5(note each file ~1meg).

Re: What is RICSAC?

Posted: Tue Jun 12, 2012 9:51 am
by MSI
June 2012: Per a request below is a table of the RICSAC tests (from the above referenced Smith & Noga paper (with a cross reference for test numbers between Calspan and S&N (Smith & Noga)
ricsac tests1.jpg
ricsac tests1.jpg (50.72 KiB) Viewed 6350 times
ricsac tests2.jpg
ricsac tests2.jpg (42.86 KiB) Viewed 6350 times

Re: What is RICSAC?

Posted: Thu Apr 25, 2019 5:25 pm
by MSI
Q: What were the speeds of the RICSAC Tests?

A: The speeds are included in the preceding charts however they are in KPH (and for reference conversion factor is
    • 1kph = 0.621371 MPH
RICSAC Speeds.jpg
RICSAC Speeds.jpg (45.65 KiB) Viewed 214 times