Research Activities: 2012

Functionally Graded Biomimetic Energy Absorption Concept Development for Transportation Systems
 
Status Complete                   View Final Report: PDF
 
Sequential Number R354
 
Identification Number 00042768
   
Matching Research Agency

Missouri University of Science and Technology
 
Principal Investigator

Victor Birman
Professor of Mechanical Engineering and Director
Missouri University of Science and Technology
Engineering Education Center, 12837 Flashing Meadows Dr., Suite 210
St. Louis, Missouri 63131
314-835-9818
vbirman@mst.edu
 
Student Involvement

N/A at this phase
 
Project Objective Develop and demonstrate the validity of the concept of shock absorbers for transportation systems utilizing a functionally graded sandwich cylinder with a high-energy absorption capacity in the low-stiffness foam layers, while maintaining the required overall stiffness and strength.
 
Project Abstract We can learn many lessons from a study of biological systems that are
applicable to engineering applications. In the proposed research we apply the observations from the study of tendon-to-bone insertion site conducted by PI with his colleagues at the School of Medicine at Washington University to a development of a robust and resilient functionally graded cylindrical sandwich shock absorber. The concept utilizes concentric foam shells of variable mass density constrained within a stiffer outer shell that reduces radial deformations of the assembly under axial shock. As was demonstrated for both biological tissues (e.g., the
tendon-to-bone insertion site) and for engineering materials (metals, ceramics, composites), a lower stiffness material possesses a higher resilience and toughness. In the considered concept, we maximize the energy dissipation of the assembly by grading the foam shells utilizing variable mass density (and accordingly, variable stiffness and strength) of foam. The energy absorption is maximized, while maintaining the prescribed deformation as well as the necessary strength of the system.
 

Relationship to other Research/Projects

This pioneering research is not related to current NUTC projects, though it utilizes the concepts learned in the course of the biomedical research
of PI (see the reference to the book published in 2013 below) and the findings from the ongoing research on polyurethane foam sandwich structures supported by NUTC (Volz, Chandrashekhara, Birman).
   

Transportation-Related Keywords

 Shock absorption, dynamics, automobiles, marine craft, railroad cars, bridge structures.
   

Technology Transfer Activities

Final report will be presented to NUTC at the end of the effort. Additionally, one research paper and two conference presentations will present the developed methodology to engineering community.
   

Project Deliverables

 The support by NUTC will be used to develop the concept and design methodology that will be presented at two professional meetings (International Mechanical Engineering Congress and Exposition 2014 and symposium “Current Trends in Damage and Fracture Mechanics” at the
20th International Symposium on Plasticity (invited paper) and published in an archival journal. These results will be immediately available to the engineering community since the IMECE Plasticity conferences are the most attended mechanical engineering meetings in North America, while the paper will be published in a high-impact, well-read journal. The results of
the study will be also presented in the final report to NUTC.
   

Anticipated Benefits

A comprehensive and validated concept with necessary design equations
suitable for an implementation in automotive, marine and railroad industries and in bridges in situations where the structure may experience impacts and shocks due to a collision, waves, landing or operational situations.

Milestones
Project Start Date: 05/01/2013
Project End Date:

12/31/2013