University of Kentucky UKnowledge Theses and Dissertations--Mechanical Engineering Mechanical Engineering 2017 SIMULATION OF HORSE-FENCE CONTACT AND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING Gregorio Robles Vega University of Kentucky, [email protected] Digital Object Identifier: https://doi.org/10.13023/ETD.2017.386 Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Vega, Gregorio Robles, "SIMULATION OF HORSE-FENCE CONTACT AND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING" (2017). Theses and Dissertations--Mechanical Engineering. 98. https://uknowledge.uky.edu/me_etds/98 This Master's Thesis is brought to you for free and open access by the Mechanical Engineering at UKnowledge. It has been accepted for inclusion in Theses and Dissertations--Mechanical Engineering by an authorized administrator of UKnowledge. For more information, please contact [email protected]. STUDENT AGREEMENT: I represent that my thesis or dissertation and abstract are my original work. Proper attribution has been given to all outside sources. I understand that I am solely responsible for obtaining any needed copyright permissions. I have obtained needed written permission statement(s) from the owner(s) of each third-party copyrighted matter to be included in my work, allowing electronic distribution (if such use is not permitted by the fair use doctrine) which will be submitted to UKnowledge as Additional File. I hereby grant to The University of Kentucky and its agents the irrevocable, non-exclusive, and royalty-free license to archive and make accessible my work in whole or in part in all forms of media, now or hereafter known. I agree that the document mentioned above may be made available immediately for worldwide access unless an embargo applies. I retain all other ownership rights to the copyright of my work. I also retain the right to use in future works (such as articles or books) all or part of my work. I understand that I am free to register the copyright to my work. REVIEW, APPROVAL AND ACCEPTANCE The document mentioned above has been reviewed and accepted by the student’s advisor, on behalf of the advisory committee, and by the Director of Graduate Studies (DGS), on behalf of the program; we verify that this is the final, approved version of the student’s thesis including all changes required by the advisory committee. The undersigned agree to abide by the statements above. Gregorio Robles Vega, Student Dr. Suzanne Weaver Smith, Major Professor Dr. Haluk E. Karaca, Director of Graduate Studies SIMULATION OF HORSE-FENCE CONTACT AND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING THESIS A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering in the College of Engineering at the University of Kentucky By Gregorio Robles Vega Lexington, Kentucky Director: Dr. Suzanne Weaver Smith, Professor of Mechanical Engineering Lexington, Kentucky 2017 Copyright 2017 © Gregorio Robles Vega ABSTRACT OF THESIS SIMULATION OF HORSE-FENCE CONTACTAND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING Rotational falls, or somersault falls, have led to serious and fatal injuries during the cross-country phase of Eventing competitions. Research to improve the safety of the sport began in 2000 after five fatal injuries occurred in the 1999 Eventing season. These efforts led to safety devices such as air jackets, improved helmets, and frangible/ deformable fences. The focus of this thesis is to develop a more complete understanding of the horse-fence interaction as the approach motion transitions to a rotational fall. To achieve this, a large distribution of inertial properties was compiled through the development of a cylinder-based inertia approximation and a citizen science effort to gather equine geometrical measurements through a survey distributed by the United States Eventing Association (USEA). Furthermore, fundamental kinematic properties of the horse and rider were gathered from the literature. These distributions were used to conduct a Monte Carlo analysis to examine if the approach conditions of the horse and rider would result in a transition to a rotational fall upon horse-fence contact. Through the analysis the sensitivity of the main control parameters was explored to determine the dominant variables in the transition. KEYWORDS: Rotational Falls, Somersault Falls, Eventing, Equestrian, Cross-Country Eventing, Equine Inertia Gregorio Robles Vega June 30, 2017 SIMULATION OF HORSE-FENCE CONTACT AND INTERACTION AFFECTING ROTATIONAL FALLS IN THE SPORT OF EVENTING By Gregorio Robles Vega Suzanne Weaver Smith, Ph. D. Director of Thesis Haluk Karaca, Ph. D. Director of Graduate Studies June 30, 2017 Dedicated to my family and friends who are always there to encourage me as I strive to accomplish my dreams. ACKNOWLEDGMENTS Thanks to God I was given this great privilege to contribute to the efforts to make this sport safer for all the participants who are passionate about Eventing. I would like to thank my academic advisor, Dr. Suzanne Smith, for not only the opportunity to be part of this effort but also for her guidance throughout the process. Dr. Smith was also very supportive in helping me graduate in time to pursue my service in the Peace Corps. I would also like to thank Lange Ledbetter, Christina Heilman, and Shannon Wood for all their hard work on this project. Lange Ledbetter, and Christina Heilman conducted undergraduate research in this project and were a fantastic help in conducting the data analysis of the Goodyear and British Eventing Safety Fences. Shannon Wood was a huge help to this effort, not only for her knowledge of Eventing, but also her work with the USEA survey was fabulous. I am very excited she will be continuing her studies and coming to the University of Kentucky to work on this effort. I would also like to thank my parents, Agustin Robles Paz and Maria Vega, as well as my siblings, Cielo Rosas Robles and Agustin Robles Vega for all their support and motivation. I would also like to thank my close friends, Colton Roach, Sarah Edrington, and Alan Varughese, who endured several difficult classes with me. I would like to thank my friends, Caterine Meza, Matthew Jehnke, and Ezra McNichols, for all their motivation. I would also like to thank all my brothers and sisters in Christ who helped encourage me. I would like to thank Dr. Suzanne Weaver Smith, Dr. Martha Grady, Dr. John Baker and Dr. Mark Hanson for their willingness to be committee members. I would like to thank all my professors at the University of Kentucky for their great job in teaching my fellow classmates and I the tools that we needed for our careers. I would like to thank the professors at the University of Kentucky Paducah Campus, Dr. Vincent Capece, Dr. William Murphy, Dr. John Baker, and Dr. Charles Lu along with all my other professors for their encouragement. Last but not least, I would like to thank the United States Eventing Association (USEA) for providing the funding for this project and giving us the opportunity to help contribute to their sport. I would also like to thank the University of Kentucky Graduate School for allowing me to be a Teaching Assistant. iii TABLE OF CONTENTS ACKNOWLEDGMENTS………………………………………………………………..iii LIST OF TABLES………………………………………………………………………..vi LIST OF FIGURES……………………………………………………………………...vii Chapter 1: Introduction ....................................................................................................... 1 1.1 Goals and Objectives ................................................................................................ 2 1.2 Thesis Outline ........................................................................................................... 3 Chapter 2: Background and Literature Review .................................................................. 4 2.1 Introduction ............................................................................................................... 4 2.2 Timeline of Safety Efforts ........................................................................................ 5 2.3 Inertial Properties .................................................................................................... 16 2.4 Kinetic properties of horses while jumping ............................................................ 19 2.5 Summary of Available Data.................................................................................... 29 Chapter 3: Inertia Approximation ..................................................................................... 32 3.1 Introduction ............................................................................................................. 32 3.2 Standing Inertia Models .......................................................................................... 32 3.2.1 Dutch Warmblood (DWB) Standing Inertia Model ......................................... 33 3.2.2 Three Cylinder Model (TCM) of Standing Inertia .......................................... 39 3.2.3 Inertia Approximation for the Rider ................................................................ 52 3.3 United States Eventing Association (USEA) Survey ............................................. 55 3.4 Results from the USEA Survey .............................................................................. 58 Chapter 4: Phenomenological Study ................................................................................