Collision avoidance

About: Collision avoidance is a research topic. Over the lifetime, 8014 publications have been published within this topic receiving 111414 citations.

Design and evaluation of a reactive and deliberative collision avoidance and escape architecture for autonomous robots

Abstract: We present the design and evaluation of an architecture for collision avoidance and escape of mobile autonomous robots operating in unstructured environments. The approach mixes both reactive and deliberative components. This provides the vehicle's behavior designers with an explicit means to design-in avoidance strategies that match system requirements in concepts of operations and for robot certification. The now traditional three layer architecture is extended to include a fourth Scenario layer, where scripts describing specific responses are selected and parameterized on the fly. A local map is maintained using available sensor data, and adjacent objects are combined as they are observed. This has been observed to create safer trajectories. Objects have persistence and fade if not re-observed over time. In common with behavior based approaches, a reactive layer is maintained containing pre-defined knee jerk responses for extreme situations. The reactive layer can inhibit outputs from above. Path planning of updated goal point outputs from the Scenario layer is performed using a fast marching method made more efficient through lifelong planning techniques. The architecture is applied to applications with Autonomous Underwater Vehicles. Both simulated and open water tests are carried out to establish the performance and usefulness of the approach.

Method and system for intelligent collision detection and warning

Abstract: A method and system for collision avoidance, carried by each aircraft, includes a miniature MEMS (MicroElectroMechanical Systems) IMU (Inertial Measurement Unit), a miniature GPS (Global Positioning System) receiver, a display, a data link receiver/transmitter, and a central processing system. Each aircraft carries a GPS receiver coupled with a self-contained miniature IMU for uninterrupted position determination. This position information is shared with other aircraft over an RF (Radio Frequency) data link. An intelligent display shows the relative positions of the aircraft in the immediate vicinity of the host aircraft and issues voice and flashing warnings if a collision hazard exists. This system provides situational awareness to the pilot and enhances the safety of flight.

Autonomous Vehicles Meet the Physical World: RSS, Variability, Uncertainty, and Proving Safety

Abstract: The Responsibility-Sensitive Safety (RSS) model offers provable safety for vehicle behaviors such as minimum safe following distance. However, handling worst-case variability and uncertainty may significantly lower vehicle permissiveness, and in some situations safety cannot be guaranteed. Digging deeper into Newtonian mechanics, we identify complications that result from considering vehicle status, road geometry and environmental parameters. An especially challenging situation occurs if these parameters change during the course of a collision avoidance maneuver such as hard braking. As part of our analysis, we expand the original RSS following distance equation to account for edge cases involving potential collisions mid-way through a braking process.

Optimal Cooperative Collision Avoidance Strategy for Coplanar Encounter: Merz's Solution Revisited

Abstract: Analytic solutions for optimal collision avoidance strategies are of great importance when setting and validating air traffic rules and as a benchmark when validating automated proximity management and collision avoidance systems. Such a solution for optimal air collision avoidance strategies for a coplanar cooperative encounter between two identical aircraft (or ships) was first presented by Merz (Proc. Joint Automatic Control Conf., Pap. 15-3:449---454, 1973; Navigation 20(2):144---152, 1973). Unfortunately, Merz provided only a very brief indicative justification for his solution. This paper presents a rigorous analysis of the problem. New results include a characterization of a complete set of extremals, justification for optimal strategies and an analysis of the properties of the regions of different optimal strategies. A simple, practical and sufficiently accurate closed form approximation for dispersal curves that partition the plane of initial positions into the regions of different optimal strategies is also presented.