Adaptive Brake by Wire from Human Factors to Adaptive Implementation

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Adaptive Brake by Wire from Human Factors to Adaptive Implementation UNIVERSITY OF TRENTO Doctoral School in Engineering Of Civil And Mechanical Structural Systems Adaptive Brake By Wire From Human Factors to Adaptive Implementation Thesis Tutor Doctoral Candidate Prof. Mauro Da Lio Andrea Spadoni Mechanical and Mechatronic Systems December 2013 - XXV Cycle 1 Adaptive Brake By Wire From Human Factors to Adaptive Implementation 2 Adaptive Brake By Wire From Human Factors to Adaptive Implementation Table of contents TABLE OF CONTENTS .............................................................................................................. 3 LIST OF FIGURES .................................................................................................................... 6 LIST OF TABLES ...................................................................................................................... 8 GENERAL OVERVIEW .............................................................................................................. 9 INTRODUCTION ................................................................................................................... 12 1. BRAKING PROCESS FROM THE HUMAN FACTORS POINT OF VIEW .................................... 15 1.1. THE BRAKING PROCESS AND THE USER -RELATED ASPECTS ......................................................................... 15 1.2. BRAKE ACTUATOR AS USER INTERFACE ................................................................................................. 16 1.3. BRAKE FORCE ACTUATION : GENERAL MOVEMENT -FORCE DESCRIPTION ....................................................... 17 2. BRAKE PEDAL FEELING AND IMPACT FACTORS ................................................................ 21 2.1. INTRODUCTION ON BRAKE FEELING ..................................................................................................... 21 2.2. IMPACT FACTORS ON BRAKE FEELING ................................................................................................... 21 2.3. RESEARCH PERFORMED BY RENAULT ABOUT FACTORS IMPACTING ON BRAKE FEELING .................................... 24 3. PEDAL FEELING DESIGN ................................................................................................. 27 3.1. HIGH -LEVEL REQUIREMENTS ............................................................................................................. 27 3.2. GENERAL ASPECTS .......................................................................................................................... 29 3.3. DESIGNING EXAMPLE ....................................................................................................................... 30 3.4. SITUATION ADAPTED PROPERTIES - USE CASES AND USERS ' EXPECTATIONS .................................................. 34 3.5. SITUATION RECOGNITION CRITERIA ..................................................................................................... 37 3.5.1. Adaptation braking speed reduction while driving or to stop .............................................. 37 3.5.2. Target and parking braking................................................................................................ 38 3.5.3. Emergency braking ............................................................................................................ 38 3.5.4. Constant speed braking (e.g. downhill) .............................................................................. 38 3.5.5. Repeated hard braking - Similar to emergency braking (e.g. race scenario) ........................ 38 3.5.6. Fading effect - Holding the vehicle and hard repeated braking actions ............................... 38 3.5.7. Stopping in vehicle manoeuvre........................................................................................... 39 3.5.8. Holding the stopped vehicle for restarting on plane road ................................................... 39 3.5.9. Holding the vehicle and adapt its position on a slope ......................................................... 39 3.5.10. Holding the vehicle stopped for restarting on a slope ......................................................... 39 3.5.11. Stop the vehicle and key off - Parking service brake............................................................ 39 3.5.12. On highway, not perform speed reduction but foot touch the brake pedal ......................... 39 3.5.13. Full loaded vehicle.............................................................................................................. 40 3.6. SCENARIO – USE CASES DESCRIPTION ................................................................................................. 40 4. PEDAL FEELING CURVES ................................................................................................ 43 4.1. ADAPT CURVE ............................................................................................................................... 44 4.2. LOW /P ARKING CURVE ..................................................................................................................... 45 4.3. EMERGENCY CURVE ........................................................................................................................ 46 4.4. CONSTANT CURVE .......................................................................................................................... 47 5. LOGICAL ARCHITECTURE AND IMPLEMENTATION ........................................................... 49 5.1. LOGICAL ARCHITECTURE FLOW .......................................................................................................... 49 3 Adaptive Brake By Wire From Human Factors to Adaptive Implementation 5.2. MATLAB /S TATE FLOW DIAGRAM ....................................................................................................... 50 5.2.1. Macro State ....................................................................................................................... 50 5.2.2. Observer Module ............................................................................................................... 52 5.2.3. States enter conditions within “Observer” module ............................................................. 52 5.2.4. State Action/Output........................................................................................................... 54 5.2.5. AccCalc Module ................................................................................................................. 54 5.2.6. “PedalControl” Module ...................................................................................................... 55 5.3. MODEL SIMULATION & DEPLOY ........................................................................................................ 57 5.3.1. Model Simulation............................................................................................................... 57 5.3.2. DSPACE MicroAutoBox HW ................................................................................................ 57 5.3.3. Model Deploy on DSPACE ................................................................................................... 58 6. MODEL VALIDATION THROUGH EXPERIMENTAL VEHICLE DATA ....................................... 61 6.1. VEHICLE INTEGRATION ..................................................................................................................... 61 6.2. TRIALS DATA ................................................................................................................................. 63 6.2.1. Adaptation braking ............................................................................................................ 63 6.2.2. Running ............................................................................................................................. 63 6.2.3. Braking action at low speed - Park/Stop ............................................................................. 64 6.2.4. Emergency braking ............................................................................................................ 65 6.2.5. Constant speed braking ..................................................................................................... 65 6.2.6. Repeated hard braking ...................................................................................................... 66 6.2.7. Keep the stopped vehicle on plain road before restart ........................................................ 66 6.2.8. Keep the vehicle and adapt its position on a slope .............................................................. 66 6.2.9. Stop the vehicle, key off and parking brake activation ........................................................ 67 6.2.10. Mixed Scenario .................................................................................................................. 67 6.3. BENCH PREPARATION ...................................................................................................................... 68 6.4. VALIDATION RESULTS ON “O BSERVER ” MODULE ................................................................................... 68 6.4.1. Repetition of all the tests ................................................................................................... 70 6.5. VALIDATION RESULTS “A CC CALC ” AND “P EDAL CONTROL ” MODULE .......................................................... 70 7. TESTS ON CLOSED-LOOP MOTOR CONTROLLER ............................................................... 71 7.1. EC MOTOR ..................................................................................................................................
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