UMTRI-2001-10 DEVELOPMENT AND REFINEMENT OF ABDOMINAL-RESPONSE CORRIDORS FINAL REPORT Project D2a Development of a Reusable, Rate-Sensitive Abdomen Warren N. Hardy Lawrence W. Schneider University of Michigan Transportation Research Institute Biosciences Division 2901 Baxter Road Ann Arbor, MI 48109-2150 Submitted to General Motors Corporation Warren, Michigan July 2001 Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. 4. Title and Subtitle 5. Report Date DEVELOPMENT AND REFINEMENT OF ABDOMINAL - July 2001 RESPONSE CORRIDORS, Project D2a - Development of a 6. Performing Organization Code 1 Reusable, Rate-Sensitive Abdomen 7. Author(s) 8. Performing Organization Report No. Warren N. Hardy and Lawrence W. Schneider UMTRI-2001-10 9. Performing Organization Name and Address 10. Work Unit no. (TRAIS) University of Michigan Transportation Research Institute 11. Contract or Grant No. 2901 Baxter Road Ann Arbor, Michigan 48109-2150 U.S.A. 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered General Motors Corporation Final Report 30500 Mound Rd. 14. Sponsoring Agency Code Warren, MI 48090-9055 15. Supplementary Notes 1The work covered by this report was financed by General Motors (GM) pursuant to an agreement with the U.S. Department of Transportation. 16. Abstract This study was conducted in support of the development of a new, reusable, biofidelic abdomen for the Hybrid III ATD in Project D2b. The goals were to resolve discrepancies and fill in some of the gaps with regard to the biomechanical response of the human abdomen to dynamic loading in the automotive environment. Three types of impact tests were conducted. Following a review and reanalysis of the data in the literature on abdominal impact response, rigid-bar tests were performed into the mid and upper abdomen of unembalmed instrumented human cadavers using different impactor speeds. Most tests were conducted using a free-back condition, but several tests were conducted using a fixed- back condition to examine the effects of body mass and spinal flexion on the response. Force-deflection corridors were developed and compared to those previously established by other researchers. The second type of test involved dynamic belt loading of the unembalmed cadaver abdomen at the lower and midabdomen regions. The results were used to establish new abdominal force-deflection corridors for belt loading. The third type of test conducted involved static deployment of passenger frontal-impact airbags into the closely positioned abdomen. Three airbag tests were conducted using three unembalmed cadavers. The deflection-time histories were used to guide the development of a repeatable high-speed surrogate airbag loading device that uses a low-mass cylinder to simulate close-proximity passenger airbag loading of the abdomen. This device was used to conduct out-of-position, airbag-loading tests into the cadaver abdomen and to develop force-deflection corridors for this type of abdomen loading. 17. Key Words 18. Distribution Statement Abdominal response, ATD, Crash dummy, Impact response, Unlimited Response corridors, Belt loading, Airbag loading 19. Security Classification (of this report) 20. Security Classi. (of this page) 21. No. of Pages 22. Price None None 88 iii iv ACKNOWLEDGMENTS This research was sponsored by the General Motors Corporation (GM) pursuant to an agreement between GM and the U.S. Department of Transportation. The authors are thankful for the opportunity and support provided for this project. This work was conducted by the University of Michigan Transportation Research Institute, Biosciences Division, and was carried out in accordance with the practices outlined by the Anatomical Donations Program of the University of Michigan Medical School. Necropsy assistance and pathology analysis were provided by Dr. Kanu Virani, consulting forensic pathologist. Thanks are also extended to members of the Biosciences Division: Brian Eby and James Whitley for fixture fabrication assistance, Thomas Jeffreys for specimen preparation assistance, Stewart Simonett for instrumentation assistance, Anthony King for data processing assistance, and to Leda Ricci for assistance in coordinating project activities. v vi CONTENTS ACKNOWLEDGMENTS ............................................................................................ v CONTENTS .................................................................................................................. vii LIST OF TABLES ........................................................................................................ ix LIST OF FIGURES ...................................................................................................... xi 1.0 INTRODUCTION AND OBJECTIVES............................................................. 1 1.1 BACKGROUND ................................................................................................... 1 1.1.1 Rigid-Bar Loading......................................................................................... 1 1.1.2 Belt Loading .................................................................................................. 4 1.2 OBJECTIVES ........................................................................................................ 5 2.0 METHODS ............................................................................................................ 7 2.1 RIGID-BAR TESTS.............................................................................................. 7 2.1.1 Free-Back Loading....................................................................................... 7 2.1.2 Fixed-Back Loading..................................................................................... 11 2.2 SEATBELT TESTS............................................................................................... 11 2.3 AIRBAG TESTS.................................................................................................... 13 2.3.1 Passenger Airbag Loading ........................................................................... 13 2.3.2 Surrogate Airbag Loading............................................................................ 16 2.4 TEST CONTROL.................................................................................................. 17 2.4.1 Facilities and Fixtures .................................................................................. 17 2.4.2 Signal Conditioning and Data Acquisition................................................... 17 2.4.3 Event Sequencing......................................................................................... 19 2.5 DATA PROCESSING........................................................................................... 19 2.5.1 Film Analysis ............................................................................................... 19 2.5.2 Data Analysis ............................................................................................... 19 3.0 RESULTS............................................................................................................... 23 3.1 FREE-BACK RIGID-BAR TESTS...................................................................... 23 3.1.1 Load and Penetration Measurement............................................................. 23 3.1.2 Load and Penetration Data ........................................................................... 24 3.1.3 Load-Penetration Responses ........................................................................ 24 3.1.4 Comparison to Cavanaugh Data................................................................... 27 3.1.5 Development of New Response Corridors................................................... 27 3.1.6 Injury-Related Findings................................................................................ 30 3.2 FIXED-BACK RIGID-BAR TESTS.................................................................... 30 3.2.1 Load and Penetration Data ........................................................................... 30 3.2.2 Load-Penetration Responses ........................................................................ 32 3.2.3 Comparison to Stalnaker Data...................................................................... 34 3.2.4 Low-Speed (3-m/s) Response ...................................................................... 34 3.2.5 Injury-Related Findings................................................................................ 34 vii 3.3 SEATBELT TESTS............................................................................................... 35 3.3.1 Load and Penetration Measurement............................................................. 35 3.3.2 Load, Penetration, and Penetration Speed Data ........................................... 37 3.3.3 Load-Penetration Responses ........................................................................ 37 3.3.4 Development of New Response Corridor .................................................... 41 3.3.5 Comparison to Miller and Cavanaugh Data................................................. 41 3.3.6 Injury-Related Findings................................................................................ 44 3.4 AIRBAG TESTS ................................................................................................... 44 3.4.1 Surrogate Airbag Load Measurement .......................................................... 44 3.4.2 Surrogate Airbag Repeatability...................................................................