Safety margins and users preferences for innovative ADAS
F. Biral, M. Da Lio, E. Bertolazzi
University of Trento
Intelligent Vehicles Symposium (IV’05), Las Vegas, Nevada, USA
6 - 8 June 2005
SAPENCE was present at this major international event with a paper outlining a methodology for combining user’s preferred driving style and safety margins into an ADAS’s module for optimal reference maneuver computation. In this paper it is shown that each user’s personal driving style can be characterized through a small set of parameters from the analysis of car longitudinal and lateral accelerations that can be easily used in Optimal Control formulation.
User acceptance is of fundamental importance to achieve rapid market penetration and widespread use of an ADAS system. A system cannot be regarded appropriate if it is not accepted by drivers or is not either cost-effective or technologically practical, even if it is expected to achieve outstanding effect in reducing accidents.
Technical integration, low costs and driver acceptance are among the basic requirements of the SASPENCE sub-project, which started with the aim of developing driver assistance systems that help drivers to avoid accidents, by appropriately sensing the surrounding scenario, monitoring driving situation and driver status and by assessing related maneuver risk. Speed and Safe Distance concepts are the focus of SASPENCE sub-project, which aims at providing seamless assistance in the longitudinal control of a vehicle by suggesting the proper velocity for the given condition in order to aid the driver in avoiding dangerous situations related to excessive speed or too small headway.
The system performances and reliability will be based, among other technologies, on reference optimal maneuver plans (which considers both obstacles and curves ahead) and related comparison with real driver’s behavior.
The module that compute these plans (the Reference Maneuver Module), is part of the decision planning chain, which links scenario interpretation to warning intervention strategies and has to best assess the imminent danger (i.e. excessive speed referred as Safe-Speed functionality and/or possible collisions referred as Safe-Distance functionality), rate the risk level and provide indication of safe distance and speed (according to all possible threats identified in the scenario).
Despite the fact that safety is a requirement that always has higher priority over user acceptance, it is of paramount importance that the module works out reference maneuvers compatible with the users’ driving style. The penalty function is the mean to implement the safe maneuver concept that has to comply with three top-level requirements:
- safety margins;
- user acceptance and mobility.
In the paper presented at the 2005 Intelligent Vehicles Symposium a new penalty function formulation was proposed, in order to include both safety criteria and preferred driving style. Further, it was shown that each user’s personal driving style could be characterized through a small set of parameters from the analysis of car longitudinal and lateral accelerations, and that these parameters can be easily used in Optimal Control formulation.
For more information, please contact SASPENCE subproject leader at [email protected] or check the SASPENCE website.