Beispielhaft am Begleiteten Fahren wurde eine Methode zur standardisierten Erfassung der Fahrsicherheit im Realverkehr entwickelt. Hierfür wurde eine Fahrstrecke mit einer Fahrdauer von etwa 90 Minuten festgelegt, die eine repräsentative Auswahl von Verkehrsszenarien enthielt, mit denen Fahrer üblicherweise beim Fahren konfrontiert werden. Diese Strecke umfasste Innerortsbereiche sowie Landstraßen- und Autobahnabschnitte. Auf dieser Strecke wurden Referenzdaten von 40 Fahrern erhoben. 26 dieser Fahrer waren zwischen 18 und 22 Jahren alt, davon hatten 17 am Begleiteten Fahren teilgenommen. Das Alter der übrigen 14 Fahrer, die allesamt nicht am Begleiteten Fahren teilgenommen hatten, lag zwischen 23 und 50 Jahren. Während der Fahrten wurden elf Variablen elektronisch im Fahrzeug erfasst (u. a. Fahrgeschwindigkeit, Abstand zum vorausfahrenden Fahrzeug). Diese elektronisch erfassten Daten wurden nach dem System I-TSA (INVENT " Traffic Safety Assessment; Glaser, Waschulewski & Schmid, 2005) ausgewertet und um Papier-und-Bleistift-Tests sowie um Beurteilungen durch den Untersuchungsleiter ergänzt. Insgesamt ergaben sich 18 Skalen. Diese zeigten hohe Reliabilitäten. Die Skalen ermöglichen eine profilartige Darstellung der Fahrsicherheit einzelner Fahrer und von Fahrergruppen, jeweils relativ zu einer Referenzgruppe. In einer Ex-Post-facto-Analyse der gegebenen Stichprobe konnte anhand dieser Skalen zwischen Fahrern, die am Begleiteten Fahren teilgenommen hatten und denen, die dies nicht getan hatten, unterschieden werden. Damit steht ein umfassendes, auf einer psychometrischen Methodik basierendes Testsystem zur Verfügung, das auf einer standardisierten Fahrprobe im Straßenverkehr basiert. Dieses System kann, ohne aufwändige und substanzielle Änderungen, auch für andere verkehrsmedizinische und verkehrspsychologische Fragestellungen eingesetzt werden.
In modern cars, driving and operating data are automatically acquired and transmitted to effectors and processors by bus systems (e.g. CAN " Controller Area Network). By reading out these data and saving them on an on-board storage device, the car becomes an experimental vehicle for test runs. Measures of driving safety can then be derived from these data. The project at hand aimed at standardizing the use of such an experimental vehicle to assess the driving safety of participants of the program "Accompanied Driving". The project consisted of three parts: (1) selection and documention of an appropriate course on public roads, (2) collection of reference data for 40 subjects, and (3) construction of a psychometric driving-safety test. In Part 1, a 78 km course was selected. It covered all three major road types: 15 km (28 min) on urban road, 24 km (25 min) on rural road and 39 km (23 min) on highways. Furthermore, the course was selected to cover a predefined set of driving tasks (e.g left turn on rural roads). The detailed documentation of the course comprised speed limits and road type. In Part 2, experimental runs of 40 subjects provided a reference data set. The sample consisted of two subsamples: 26 younger subjects (aged between 18 and 22 years), 17 of which with and 9 without former "Accompanied Driving" , 14 older subjects (aged between 23 and 50 years), all without experience in "Accompanied Driving". In Part 3, a psychometric test for traffic safety was developed. Eleven variables (e.g., "violation of speed limit", "heading time") were recorded electronically. Simple statistical calculations of these variables do not suffice as psychometric measures of driving safety. In earlier projects, the authors have developed the system I-TSA (INVENT " Traffic Safety Assessment , W. R. Glaser, Waschulewski, and Schmid, 2005). It was taken up, improved and designed more user centered. Through factor analysis, eight scales were found as components of driving safety. They were normalized and standardized by frequency transformation at a mean of 100 and a standard deviation of 10. The scales were '1 speed', '2 acceleration', '3 heading time', '4 lane keeping', '5 turn indicator', '6 steering-wheel movements' (steering entropy), '7 mental effort' (RSME = Rating Scale of Mental Effort, German version by EILERS, NACHREINER, and HÄNECKE, 1986), and '8 electronically recorded driving errors'. The electronic measures were complemented by paper-pencil tests for the subjects and the experimenter to compare conventional safety and electronic data. The subjects completed a questionnaire for driving experience which contained 47 items, among them all 20 items of the technology/risk questionnaire by BR. FÄRBER and BE. FÄRBER (2003). By factor analysis, five scales were extracted: 'timidity, fear of overload or excessive demand', 'joy of driving', 'enthusiasm for technology', 'self-confidence as driver', and 'observing of norms and rules'. After each driving test, the experimenter completed a form with three rating scales for driver- behavior: First, he rated the impairment of driving by 33 items of an error list. These ratings were condensed to a single mean. Second, he rated driving safety of 9 more general driving habits (e.g. choice of speed or surpassing). A factor analysis of the 9 general habits provided the two factors "errors" and "lapses" according to the DBQ (Driver Behaviour Questionnaire , REASON, MANSTEAD, STRADLING, BAXTER, and CAMPBELL, 1990). Third, he characterized the driving style by a semantic differential with 11 adjective pairs (e.g. considerate " inconsiderate or aggressive " defensive). By factor analysis, the semantic differential yielded two scales, 'stress' and 'adjustment'. Thus, there were 8 I-TSA, 5 subject- driving-experience, and 5 experimenter scales. Together, these 18 scales form a standardized test of driving safety, which provides a profile for each subject. Most of these scales are highly reliable with Cronbach- α > 0.8. The factor analysis of the 18 scales explains 75.8 % of the total variance by two strong and four moderate factors. Thus, the test measures a construct of driving safety with 6 dimensions. Factor 1 comprises all driving errors as measured or rated. Factor 2 represents the driving-experience variables and mental effort. Factor 3 contains the electronically recorded variables of driving dynamics I-TSA 1 to I-TSA 3. The residual 4 variables load on the additional 3 minor factors. There was no experimental design for differences of groups. However, a statistical analysis as an ex-post-facto experiment was possible. Although it showed no difference between the subgroups for sex and age, a logistic regression correctly assigned the subjects to the groups with and without Accompanied Driving. A multivariate F-test yielded single sided significance between these groups.
Ein Verfahren zur Messung der Fahrsicherheit im Realverkehr entwickelt am Begleiteten Fahren.
A method to assess the safety in actual driving developed on accompanied driving
2013-09-09
Book
Electronic Resource
German
DDC: | 620 |
SERVICE - Fahrsicherheit - Aktion Besser Fahren
Online Contents | 1999
ELBA - Federal Highway Research Institute (BASt) | 2012
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