Different Driver Attention States

Transkript

1 Effectiveness of Forward Collision s for Different Driver Attention States Neli Ovcharova 1, Dr. Michael Fausten 1, Prof. Frank Gauterin 2 1 ) 2 ) Alcalá de Henares, June 6,

2 Introduction ti n = 310,806 Rear-end end crashes: second largest accidents with casualties 2% 15% 20% 15% 7% 4% collision type One main reason for rear-end end collisions is driver inattentiveness 9% 28% 70 collision with... parked vehicle vehicle moving ahead or waiting vehicle moving laterally in same direction oncoming vehicle vehicle which turns into or crosses a road pedestrian fixed Object or vehicle leaving carriageway Accident of another kind (unknown, not fixed object, animal ) Sources: StBA, GIDAS, Year 2009 [%] Inattentive driver Distracted driver Source: LeBlanc et al Poor visibility Aggressive driver Tailgate Cut-in 2

3 Collision i Systems Aim of collision warning systems: help the driver to prevent or mitigate collisions Challenge: to convey the same urgency and to obtain a high effectiveness for attentive and inattentive driver state at the same time. Approach: Adaptive Collision System Target: Benefit and acceptance increase of common collision i warning systems. Data Attentiveness Criticality Driver state System 1 for attentive drivers 2 for inattentive drivers dependent on Assumption for driver reaction time 3

4 Proceedings for HMI Evaluation Requirements A warning should attract the driver s attention to the dangerous situation generate a collision mitigating driver reaction possess a minimum of intensity, multimodality and appropriate warning point in time be compatible to the critical event be not too complex and be consistent with other indication signals be acceptable by the driver Procedure The investigation of the driver behavior with selected HMIs was carried out in two stages in a fixed based simulator. Stage 1 Acoustical Stage 2 Visual 4

5 Methodology 58 participants p (32 first stage, 26 second stage) completed two drives First drive: inattentive driver state Second drive: attentive driver state Secondary task: Navigation Instruction Design of the most frequent rear-end crash scenario (Wiacek et.al. (1999)) Subject Vehicle Leading Vehicle (Braking) d_x = 40 m 5

6 Stage 1: Acoustical Stage 1 Stage 2 Acoustical Visual Target of Stage 1: Determination of an acoustical HMI, which provokes short reaction times for attentive and inattentive driver state. Selected acoustical Signals for the evaluation: Earcon: Alarm 1, Alarm 2 Auditory Icon: tire screeching Hybricon: Combination of earcon and auditory icon (tire screeching) Speech Message: Bremsen, which means to brake in german 6

7 [ms] Rea action Time 7 IEEE IV'12 INTELLIGENT VEHICLES SYMPOSIUM Results: Inattentive ti driver state t Inattentive Stage 1 Stage 2 Acoustical Visual Indicative reduction of reaction 29 times by the Speech Message (p 35 = > 0.05). 05) An analysis was performed with 41 P75 the best two tones (Speech P50 Message & Alarm2) and the P25 control group revealed an indicative reaction time reduction 47 (p = > 0.05) An acoustical warning with a clear 39 message such as the speech Alarm1 Alarm2 Auditory Hybricon Speech Control message is necessary to guide Icon Message group (N = 5) (N = 5) (N = 5) (N = 5) (N = 5) (N = 7)* the drivers attentiveness to the *) no acoustical ca signal, statical warning triangle imminent danger

8 Results: Attentive ti driver state t Attentive Stage 1 Stage 2 Acoustical Visual Rea action Time [ms] Alarm1 (N = 5) Alarm2 (N = 5) Auditory Icon (N = 5) Hybricon (N = 5) Speech Message (N = 3) Control group (N = 7)* Experiment set-up affect the reaction of the drivers in the second drive No significant reduction of the reaction times in attentive driver state was observed. *) no acoustical ca signal, statical warning triangle 8

9 Stage 2: Visual Stage 1 Stage 2 Acoustical Visual Target of Stage 2: Determination of a visual HMI, which provokes short reaction times for attentive and inattentive driver state. Visual warning display in HUD. Selected visual signals for the evaluation: triangle Brake bar Brake light Collision notification 9

10 Results: Inattentive ti driver state t Inattentive Stage 1 Stage 2 Acoustical Visual Re eaction Tim me [ms] Brake bar Brake light Collision Control triangle notification group (N = 5) (N = 5) (N = 5) (N = 5) (N = 6)* No additional reaction time reduction in an inattentive driver state could be demonstrated for the examined visual warnings (p >> 0.05) The acoustical warning is the main component of a multimodal HMI for inattentive driver. An intuitive and simple visual warning could serve to affirm the audible warning. *) speech message, no visual warning 10

11 Results: Attentive ti driver state t Attentive Stage 1 Stage 2 Acoustical Visual [ms]1400 Tim1200 Re eaction me Brake bar Brake light Collision Control triangle notification group (N = 5) (N = 5) (N = 4) (N = 5) (N = 5) * 2 Significant reaction time reduction by the brake bar compared to the collision i notification (p = < 0.05). A comparison between brake bar and control group revealed statistical significance (p = < 0.05). A simple, intuitive visual signals with a clear message can reduce the reaction time of attentive di drivers. *) no acoustical ca warning, no visual warning 11

12 Summary An acoustical warning with clear message reduces the reaction time of inattentive drivers indicatively. A simple, intuitive visual warning compatible with the critical event and with a clear message reduces the response times of attentive drivers significantly. An adaptation of the warning intensity and modalities to the driver s attention can be useful to increase the benefit and the customer acceptance of collision warning systems. 12

13 THANK YOU FOR YOUR ATTENTION 13