EML 4905 Senior Design Project A B.S. THESIS PREPARED IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE DEGREE OF BACHELOR OF SCIENCE IN MECHANICAL ENGINEERING FSAE 2015 Chassis and Suspension Final Report Alejandro Diaz Osvaldo Fernandez Ricardo Gonzalez Christian Ramos Advisor: Professor Andres Tremante November 24, 2014 This B.S. thesis is written in partial fulfillment of the requirements in EML 4905. The contents represent the opinion of the authors and not the Department of Mechanical and Materials Engineering. P a g e | i Ethics Statement and Signatures The work submitted in this B.S. thesis is solely prepared by a team consisting of Alejandro Diaz, Osvaldo Fernandez, Ricardo Gonzalez, and Christian Ramos and it is original. Excerpts from others’ work have been clearly identified, their work acknowledged within the text and listed in the list of references. All of the engineering drawings, computer programs, formulations, design work, prototype development and testing reported in this document are also original and prepared by the same team of students. Alejandro Diaz Osvaldo Fernandez Ricardo Gonzalez Christian Ramos Team Leader Team Member Team Member Team Member Dr. Andres Tremante Faculty Advisor P a g e | ii Table of Contents List of Figures ................................................................................................................................ iv List of Tables ................................................................................................................................ vii Abstract ........................................................................................................................................ viii 1. Introduction ................................................................................................................................. 1 1.1 Problem Statement ................................................................................................................ 1 1.2 Motivation ............................................................................................................................. 1 1.3 Literature Survey .................................................................................................................. 3 1.3.1 Vehicle Handling Characteristics................................................................................... 4 1.3.2 Suspension Rates and Damping ..................................................................................... 6 1.3.3 Suspension Geometry .................................................................................................... 9 1.3.4 Chassis Design ............................................................................................................. 11 1.4 Addressing Global Design .................................................................................................. 12 1.5 Constraints and Other Considerations ................................................................................ 13 2. Conceptual Design (Design Alternatives) ................................................................................ 15 2.1 Material Selection ............................................................................................................... 15 2.1.1 Suspension ................................................................................................................... 15 2.1.2 Chassis ......................................................................................................................... 16 2.2 Design Process .................................................................................................................... 16 2.3 Prototype 1 .......................................................................................................................... 20 2.3.1 Chassis ......................................................................................................................... 21 3. Proposed Design ....................................................................................................................... 41 3.1 Chassis ................................................................................................................................ 41 3.1.1 Ergonomic Integration ................................................................................................. 41 3.1.2 Frame Improvements ................................................................................................... 45 3.2 Suspension .......................................................................................................................... 49 3.2.1 Upright and Wheel Hub ............................................................................................... 49 3.2.2 Suspension Geometry .................................................................................................. 54 3.3 Standards Used in the Project ............................................................................................. 59 3.3.1 System Level Standards ............................................................................................... 59 3.3.2 Component Level Standards ........................................................................................ 59 4. Project Timeline & Responsibilities ......................................................................................... 60 4.1 Gantt Chart .......................................................................................................................... 60 4.2 Task Distribution ................................................................................................................ 61 5. Engineering Design and Analysis ............................................................................................. 61 5.1 Evaluation of Raw Tire Data .............................................................................................. 61 5.2 Elementary Vehicle Analysis .............................................................................................. 71 5.3 Suspension Roll and Ride Rates ......................................................................................... 75 5.4 Suspension Geometry ......................................................................................................... 80 5.4.1 Suspension Geometry Camber analysis W/O Body Roll for prototype 1.................... 80 5.4.2 Suspension Geometry Camber analysis W/O Body Roll for prototype 2.................... 83 5.5 Chassis Stiffness ................................................................................................................. 88 5.6 FEA Analysis ...................................................................................................................... 90 5.5.1 Chassis ......................................................................................................................... 90 5.5.2 Suspension ................................................................................................................... 94 P a g e | iii 5.6. Cost Analysis ................................................................................................................... 100 5.6.1 Prototype 1 ................................................................................................................. 101 5.6.2 Prototype 2 ................................................................................................................. 103 6. Prototype 2 Manufacturing ..................................................................................................... 105 6.1 Frame and Suspension Manufacturing.............................................................................. 105 6.2 Upright and Hub Manufacturing ....................................................................................... 112 7. Testing and Evaluation ........................................................................................................... 116 7.1 Testing............................................................................................................................... 116 7.2 Evaluation ......................................................................................................................... 118 8. Design Considerations ............................................................................................................ 119 8.1 Maintenance ...................................................................................................................... 119 8.2 Environmental Impact ....................................................................................................... 119 8.3 Risk Assessment ............................................................................................................... 119 9. Conclusion .............................................................................................................................. 121 10. References ............................................................................................................................. 122 11. Appendix ............................................................................................................................... 123 Appendix A: 2015 FSAE Rules .............................................................................................. 123 Appendix B: Sample .TIR File for Tire Analysis ................................................................... 141 Appendix C: Formulas