Active Safety Functions Research Articles

Situation Assessment of an Autonomous Emergency Brake for Arbitrary Vehicle-to-Vehicle Collision Scenarios

The autonomous emergency brake (AEB) is an active safety function for vehicles which aims to reduce the severity of a collision. An AEB performs a full brake when an accident becomes unavoidable. Even if this system cannot, in general, avoid the accident, it reduces the energy of the crash impact and is therefore referred to as a collision mitigation system. A new approach for the calculation of the trigger time of an emergency brake will be presented. The algorithm simultaneously considers all physically possible trajectories of the object and host vehicle. It can be applied to all different scenarios including rear-end collisions, collisions at intersections, and collisions with oncoming vehicles. Thus, 63% of possible accidents are addressed. The approach accounts for the object and host vehicles' dimensions. Unlike previous work, the orientation of the vehicles is incorporated into the collision estimation.

Trends in Crash Detection and Occupant Restraint Technology

In the past two decades, occupant restraint systems for automobiles have made considerable progress globally. There has been a tremendous increase in the complexity and sophistication of functional requirements. Particularly significant in the overall evolution of restraint systems is the growth in electronics content, which is concurrent with similar phenomena in the automotive world, as well as in many other technology-related fields. In conjunction with this trend, the shift to digital components and subsystems expanded, while the design of restraint systems has become more diversified with enhanced adaptability and flexibility. In addition to the airbags that are standardized for passenger vehicles, there has been a whole spectrum of emerging safety features that provide additional safety improvements. For example, rollover and occupant sensing are being added onto an integrated occupant protection system. Global positioning systems are coupled with crash sensors into emergency notification services. Increasingly, vehicles are now being equipped with active safety systems. The availability of both passive restraints and active safety functions will allow an additional layer of synergistic integration across safety systems. Research and developments in vehicular safety can be expected to remain active in the foreseeable future. This paper describes the system-level design trends that have occurred in the past and offers a perspective of future design transition in automotive restraint systems

COOPERATIVE COGNITIVE AUTOMOBILES AND DIVERSITY IN COGNITION

This contribution outlines a joint project between Universität Karlsruhe (TH) and Technische Universität München on cooperative cognitive vehicles. Emphasis is placed upon reliability assessment of environment information as achieved by automotive video, radar, or lidar sensors, as this is a crucial issue for the realization of preventive and active safety functions. This contribution approaches reliability within the cognition chain from the viewpoint of diversity. Vehicle environment perception and behavior generation allow exploitation of diversity at various levels that are outlined in the paper: Cooperative exploitation of diverse features as well as of information from diverse sensors are prominent examples that have been elaborated in literature. A further source of diversity that has attracted little work so far is the cooperative exploitation of information between diverse levels of the perception chain. Finally, cooperative evaluation of the diverse environment information acquired by multiple vehicles in mixed traffic is proposed. Through implementation of diversity on multiple levels, environment perception and behavior generation may be conducted at a level of reliability that allows realization of safety functions.