Modelling Car Drivers’ Start of Braking When the Forward Vehicle is Stationary or Moving with Constant Velocity
Typ
Examensarbete för masterexamen
Master Thesis
Master Thesis
Program
Publicerad
2012
Författare
Ergitürk Hande, Ayca
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
This thesis work conducts a study on modelling car drivers’ start of brake when forward vehicle is stationary or when it is moving with constant velocity. The euroFOT data collected by Volvo Car Corporation in the Gothenburg area of Sweden has been the main data source for modelling purposes. The data segments used consist of braking events where the host vehicle is approaching the forward vehicle. The selection of data segments was further limited by addition of the constraint the forward vehicle has constant velocity or is stationary. A thorough literature investigation recommended several approaches to predict driver’s brake initiation in terms of distance as well as other perceptual or physical factors that are decisive on driver’s braking behaviour. With the help of previous knowhow, distance to target vehicle at drivers’ brake initiation and inverse time to collision (TTC) approaches have been selected for modelling. Vehicle dynamics related factors such as velocity, acceleration, yaw rate etc. and other factors presented in literature such as reaction time, visual angle, TTC, preferred time headway, preferred distance to vehicle ahead have been subjected to a correlation analysis to identify the significant parameters related to drivers’ braking distance and inverse TTC preference. Single and multiple linear regression analysis have been applied to the combination of selected parameters to establish an equation, which gives the minimum prediction error. Both normal and lognormal values of measured braking distance were used in regression analysis. The results suggested that, for brake events where target vehicle is stationary, the braking distance is best predicted with normal braking distance based modelling. On the contrary, modelling based on lognormal braking distance offered better estimation results for constant target vehicle velocity events. The best population fit and smallest prediction error is resulted with lognormal braking distance based modelling for constant target vehicle velocity condition. Interestingly, the inverse TTC approach provided promising results for the constant target vehicle velocity condition whereas the case for stationary target vehicle, inverse TTC did not lead to strong results. Finally, the study is concluded with various recommendations for possible future investigations.
Beskrivning
Ämne/nyckelord
Maskinteknik , Hållbar utveckling , Annan maskinteknik , Farkostteknik , Transport , Mechanical Engineering , Sustainable Development , Other Mechanical Engineering , Vehicle Engineering , Transport