In recent years, electric vehicles (EVs) have been given increased attention due to rising costs of petrol-based fuels and higher emission awareness. EVs are a promising technology for reducing environmental effects of road transport, but they are not yet competitive with conventional vehicle technology. Uncertainties regarding costs, performance, range and infrastructure requirements such as electricity supply held back a wide spread on the vehicle market. However, it is expected that fully-electric car sales will constantly grow, especially for the purpose of short urban travelling. In general, electrification is going to play an important role in city planning as well as public and individual transport solutions. In order to pave the way for integrating EVs in modern transport systems, road safety issues must be taken into account. On the one hand, electric engines are quiet, which leads to a lower perceptibility for vulnerable road users, particularly at low speeds. On the other hand, EVs could show different vehicle dynamics due to a higher engine torque, different mass distribution and energy recuperation techniques. Since little research on safety of EVs has been conducted so far, some research questions still remain unanswered: What are the differences in driving dynamics between EVs and conventional cars? Do drivers change their behaviour in EVs? Which influence does the recuperation have on driving and braking behaviour? In this project, we explore the differences in vehicle dynamics and drivers´ behaviour between EVs and conventional cars. Our research aimed at revealing potential safety Endbericht E-FFEKT 6 von 95 risks due to a higher EV penetration, e.g. incidents or conflicts with other road users that primarily occur with EVs involved. To do this, we conducted a real-world driving study with 90 participants on a pre-defined route. Since the route took approximately one hour, only short-term behaviour could be observed. Each participant had to complete the route with an electric as well as a conventional car. Besides video recordings from a position similar to the drivers´ point of view, we collected 3D accelerometer and GPS data. Our analysis focussed on pre-defined regions of interest located on the test route, including curves, roundabouts, intersections as well as pedestrian and railway crossings. Additionally, findings were derived from questionnaires that were completed by each participant and included subjective information about safety perception and driving style, amongst other. Our results show that the effects of an electric engine on "non-extreme" vehicle dynamics are negligibly low compared to other factors such as transmission type. Surprisingly high decelerations were measured during the EV´s recuperation phases, which might lead to unexpected and risky driver reactions. It might also affect follow-up road users, since the braking lights are not always activated. In general, our participants felt safe and got used to the EV quickly. Long-term behaviour, such as driving style adaptations according to the state of battery charge will be determined in future research.
|Titel||E-FFEKT: Auswirkung von E-Kfz auf Fahrdynamik und Verkehrskonflikte|
|Publikationsstatus||Veröffentlicht - 2013|
- Ehemaliges Research Field - Mobility Systems