ABSTRACT Designing, Constructing, and Testing a Second-Generation Prototype Mechanical Hippotherapy Horse Heather Denae Benoit, M.S.B.M.E. Mentor: Brian A. Garner, Ph.D. The use of horses as a means of therapy has been documented for some time. To determine why this type of therapy works and to provide a means of expanding its accessibility, a mechanical horse has been developed. Data collected on the movement of live horses during a previous study was used as a target motion in the development of a prototype mechanical horse. This mechanism was designed to be capable of reproducing that motion. For this prototype, the base remains stationary and a suspended saddle seat moves in a pattern replicating that of a live horse. The saddle is suspended by eight cables which are displaced by eight distinct cams. The cam set can be exchanged for various cam sets which correspond to different prescribed movements. Testing revealed good agreement between the motion of the prototype and the target, but improvements can be made in the measure of z-translation. Designing, Constructing, and Testing a Second-Generation Prototype Mechanical Hippotherapy Horse by Heather Denae Benoit, B.S.E. A Thesis Approved by the Department of Mechanical Engineering ___________________________________ William Jordan, PhD., Chairperson Submitted to the Graduate Faculty of Baylor University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Biomedical Engineering Approved b y the Thesis Committee ___________________________________ Brian A. Garner, PhD., Chairperson ___________________________________ Carolyn T. Skurla, PhD. ___________________________________ Beth A. Lanning, PhD. Accepted by the Graduate School August 2011 ___________________________________ J. Larry Lyon, P h.D., Dean Page bearing signatures is kept on file in the Graduate School. Copyright © 2011 by Heather Denae Benoit All rights reserved TABLE OF CONTENTS LIST OF FIGURES ...................................................................................................... vii LIST OF TABLES ....................................................................................................... xii LIST OF ABBREVIATIONS ...................................................................................... xiii PREFACE ....................................................................................................................xiv ACKNOWLEDGMENTS ............................................................................................. xv DEDICATION ........................................................................................................... xvii EPIGRAPH ............................................................................................................... xviii CHAPTER ONE..............................................................................................................1 Introduction .................................................................................................................1 History of Horse and Man ........................................................................................1 Purpose ....................................................................................................................2 Thesis Overview .......................................................................................................3 CHAPTER TWO .............................................................................................................5 Background ..................................................................................................................5 The Medicinal Use of Horses....................................................................................5 Indications and Contraindications .............................................................................7 Comparison with Alternative Therapies ....................................................................8 Hippotherapy Staff ................................................................................................. 11 Professional Licensing and Certification ................................................................. 12 Horse Selection and Training .................................................................................. 12 Hippotherapy Facilities ........................................................................................... 13 iii Hippotherapy Sessions and Administration ............................................................. 13 The Mechanics of Hippotherapy ............................................................................. 16 Physical Benefits .................................................................................................... 18 Cognitive Benefits .................................................................................................. 20 Emotional Benefits ................................................................................................ 20 Social Benefits ....................................................................................................... 21 Limitations of Hippotherapy ................................................................................... 21 Advantages of a Mechanical Horse ......................................................................... 23 CHAPTER THREE ....................................................................................................... 25 Mechanical Horses ..................................................................................................... 25 Prior Efforts in Mechanical Horse Design ............................................................... 25 Various Uses of Mechanical Horses........................................................................ 27 Robotic Horses for Research, Exercise, and Therapy .............................................. 33 Modern Mechanical Horses .................................................................................... 36 Literature Review: Studies Conducted with Mechanical Horses .............................. 38 Conclusion ............................................................................................................. 42 CHAPTER FOUR ......................................................................................................... 44 Mechanical Horse Prototype #1: Mr. Ed ..................................................................... 44 Equine Motion Data Collection .............................................................................. 45 Design and Construction ......................................................................................... 46 Results and Limitations of Mr. Ed .......................................................................... 50 Second-Generation Development ........................................................................... 53 CHAPTER FIVE ........................................................................................................... 55 Methods and Prototype Design ................................................................................... 55 iv Design #1 ............................................................................................................... 55 Design #2 ............................................................................................................... 65 Final Design: The Wild Bill Prototype .................................................................... 68 CHAPTER SIX ............................................................................................................. 83 Results ....................................................................................................................... 83 Graph Set 1: Effect of Stabilization ........................................................................ 86 Graph Set 2: Effect of Speed................................................................................... 89 Graph Set 3: Effect of Load .................................................................................... 92 Graph Set 4: Prototype #2, Target Motion, and the Panasonic Joba ......................... 95 CHAPTER SEVEN ..................................................................................................... 111 Discussion................................................................................................................ 111 Significance .......................................................................................................... 111 Analysis ............................................................................................................... 112 Limitations and Errors .......................................................................................... 116 CHAPTER EIGHT ...................................................................................................... 118 Conclusion ............................................................................................................... 118 Future Work ......................................................................................................... 118 APPENDIX A ............................................................................................................. 122 Construction Drawings for Prototype #2 .................................................................. 122 Base Subsystem 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