1. TRANED2010TRBPPTjgs0501101 MOBILITY SCOOTERS AND USER CHARACTERISTICS AT CROSSINGS AND INTERSECTIONS John G. Schoon University of Southampton, Transportation Research Group

2. TRANED2010TRBPPTjgs0501102 Objective: Improved geometric design of road crossings for mobility scooter users. Current problems: Users’ risk of collision with motor vehicles not stopping due to inadequacies in: Driver performance Approaching vehicle(s’) deficiencies Infrastructure Operational procedures Problem consequences – reduced mobility of disabled people

3. TRANED2010TRBPPTjgs0501103 Aproach to Improved Geometric Design – Configure crossings to accommodate users Scooter users’sight lines – to enables scooter user who is aware of his or her abilities, to cross the carriageway to a point where no risk of collision with an approaching vehicle occurs. Considerations: distance to approaching vehicles, clearance from obstructions; user’s vision angle; and, user’s scanning time. Crossing movement timing – User based: observation-reaction time; and, Scooter based: acceleration, crossing velocity, deceleration, safety margin

4. TRANED2010TRBPPTjgs0501104 USER’S SCANNING ANGLES Required corner scanning angle B A Range of actual scanning angles

5. TRANED2010TRBPPTjgs0501105 EFFECT OF MIRRORS ON SIGHT LINES

6. TRANED2010TRBPPTjgs0501106 EFFECTS OF CROSSING LOCATION ON USER SIGHT LINES

7. TRANED2010TRBPPTjgs0501107 CROSSING TIME COMPONENTS Safety margin time Vulnerability time during crossing Observation- reaction time Observation- reaction time

8. TRANED2010TRBPPTjgs0501108 TIME-DISTANCE DIAGRAM OF CROSSING MOVEMENT Time Observation- reaction time Front of scooter Rear of scooter Safety margin time Total time required by mobility scooter for safe crossing Length of scooter Length of scooter time Distance

9. TRANED2010TRBPPTjgs0501109 GEOMETRIC DESIGN REQIREMENTS FOR MOBILITY SCOOTERS AT CROSSINGS Analysis of sight lines User scanning angles Location of crossing relative to sight lines to approaching vehicles Assumption that scooter users cannot take evasive action Consideration of scooter and user characteristics: Observation-reaction time length of scooter Safety margin Turning radius of scooters adjacent to crossing Scooter crossing speed relative to approaching vehicle speed Footway width and slope characteristics