DOT HS 811 448 March 2011 A Study of Motorcycle Rider Braking Control Behavior This publication is distributed by the U.S. Department of Transportation, National Highway TrafficSafetyAdministration,intheinterestofinformationexchange.Theopinions,findingsand conclusions expressed in this publication are those of the author(s) and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its content or use thereof. If trade or manufacturers’ names or products are mentioned, it is because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers. Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES March 2011 COVERED Final Report, September 2008 – September 2009 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS A Study of Motorcycle Rider Braking Control Behavior DTNH-05-D-01002, Task Order 0016 6. AUTHOR(S) Subcontract No. 8172-S-05 J.F. Lenkeit, B.K. Hagoski, A.I. Bakker Task Order #1 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Dynamic Research, Inc REPORT NUMBER 355 Van Ness Ave #200 DRI-TR-09-12-4 Torrance, CA 90501 9. SPONSORING/MONITORING AGENCY NAME(S) AND 10. SPONSORING/MONITORING ADDRESS(ES) AGENCY REPORT NUMBER U.S. Department of Transportation National Highway Traffic Administration 1200 New Jersey Avenue, SE Washington, DC 20590 11. SUPPLEMENTARY NOTES This project was managed by Dr. Paul Rau of the National Highway Traffic Safety Administration. 12a. DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE This document is available to the public through the National Technical Information Service www.ntis.gov 13. ABSTRACT (Maximum 200 words) This document reports a study wherein a motorcycle riding simulator was used to study how non-expert motorcycle riders use conventional brakes in emergency braking situations. Sport-touring and Cruiser motorcycle configurations were used. Sixty eight rider-subjects, divided into those who typically ride Cruisers, and those who primarily ride Sport motorcycles, were exposed to traffic situations requiring a range of braking from normal slowing to emergency braking. Braking behavior data were obtained from recordings of rider control inputs, motorcycle response, and interactions with other vehicles. Rider characteristic data were obtained from questionnaires. Data from these sources were analyzed to investigate possible relationships between rider characteristics, braking behavior and event outcome. Emergency braking behavior was analyzed based on two scenarios involving an opposing vehicle moving rapidly into the rider-subject’s lane, requiring rider-subjects to brake in order to avoid collision. There were no cases where the rider-subject used only the rear brake, though some riders used only the front brake. Analyses of event outcome indicated that a rider’s initial braking, with respect to both timing and magnitude, is important in determining the event outcome. Linear and logistic regression analyses produced generally poor correlation between individual rider factors and braking behavior or event outcome. 14. SUBJECT TERMS 15. NUMBER OF Motorcycle, rider behavior, simulator, braking, brakes PAGES 222 16. PRICE CODE 17. SECURITY 18. SECURITY 19. SECURITY 20. LIMITATION CLASSIFICATION OF REPORT CLASSIFICATION OF CLASSIFICATION OF ABSTRACT Unclassified THIS PAGE OF ABSTRACT Unclassified NSN 7540-01-280-5500 Standard Form 298 (rev. 2-89) Prescribed by ANSI Std. 239-18, 298-102 i TABLE OF CONTENTS Page Executive Summary ............................................................................................ 1 I. INTRODUCTION ....................................................................................... 5 A. Background .................................................................................... 5 B. Project Objectives ........................................................................... 7 II. TECHNICAL APPROACH ......................................................................... 8 A. Experimental Design ...................................................................... 9 B. Riding Simulator Setup ................................................................... 9 1. Simulator Overview .............................................................. 9 2. Motorcycle Cab ...................................................................11 3. Vehicle Dynamics Model ....................................................14 4. Data Acquisition ..................................................................17 5. Aural cues ...........................................................................18 6. Graphical Roadways ...........................................................18 7. Riding Scenarios and Tasks ...............................................22 8. Video Recording .................................................................23 C. Rider Participant Selection and Protocols ......................................24 1. Recruiting and Screening ...................................................24 2. Participant Protocols ...........................................................25 D. Experimental Protocols ..................................................................26 1. Safety Precautions ..............................................................26 2. Run Procedures and Schedule ...........................................26 ii TABLE OF CONTENTS (CONTD) Page E. Data Analysis ................................................................................28 1. Experimental Measures ......................................................28 2. Principal Components Analysis ..........................................32 3. Logistic Regression ............................................................33 F. Simulator Validation .......................................................................36 III. RESULTS .................................................................................................38 A. Front/Rear Braking Use and Relationship to Rider Factors ...........39 1. Front/Rear Brake Use .........................................................39 2. Relationship of Front/Rear Brake Usage to Participant Factors ..............................................................44 B. Braking Behavior Related to Braking Event Outcomes .................46 1. Probability of Collision ........................................................47 2. Probability of Capsize .........................................................51 C. Rider Factors Related to Braking Behavior and Event Outcome ..............................................................................54 1. Single Variable Regression and Comparisons ....................54 2. Relationship Between Individual Rider Factors and Scenario Outcome ..............................................................62 3. Relationship Between Rider Factors and Braking Behavior Variables.................................................65 iii TABLE OF CONTENTS (CONTD) Page IV. DISCUSSION AND CONCLUSIONS .......................................................68 A. Data Treatment and Interpretation ................................................68 B. Front and Rear Brake Usage .........................................................68 C. Braking Event Outcomes Related to Braking Control Behavior ............................................................................69 D. Rider Factors .................................................................................72 E. Improvements For Future Studies .................................................73 F. Riding Simulator as a Research Tool ............................................74 G. Possible Follow-On Studies ...........................................................75 REFERENCES ...................................................................................................77 APPENDIX A Description of Scenarios ........................................................ A-1 APPENDIX B Participant Documents ........................................................... B-1 APPENDIX C Run Procedure Documents, Participant Instructions, and Questionnaires for Use in the Motorcycle Braking Study ......................................................................... C-1 APPENDIX D Rider Factors.......................................................................... D-1 APPENDIX E Logistic Regression Results ................................................... E-1 APPENDIX F Computed Variables ................................................................F-1 iv LIST OF FIGURES Page 1. Cruiser and Sport-Touring Motorcycle Cabs ............................................13 2. Forward Mounted Footrest and Rear Brake Pedal ..................................14 3. Roadway Geometry .................................................................................19 4. Example Suburban Intersections .............................................................20 5. Examples of Rural Intersections...............................................................21 6. Simulator Cab and Video Outputs ............................................................23 7. Example Results for Logistic Regression .................................................34 8. Distribution of Front/Rear Braking