Showing papers on "Collision avoidance published in 1980"

Interference detection and collision avoidance among three dimensional objects

Abstract: Two methods for detecting intersections among three dimensional objects are described. The first method involves detecting overlap among the projections of the objects on a given set of planes. The second method uses a three dimensional octree representation of the objects. Intersections are detected by traversing the trees for the obstacles and the moving objects. Application of the methods to collision avoidance is discussed.

Vehicle collision avoidance system

Abstract: An automatically guided vehicle (110) is disclosed which follows guide lines positioned in a predetermined guide path (102) on the floor. The guide path (102) includes coded markings and the vehicle comprises sensing circuitry (210) capable of sensing the markings and generating proximity signals indicative thereof. The coded markings can indicate approach of the vehicle into a "congestion" zone wherein other vehicles similarly situated can cause hazardous conditions therein. Radio frequency (RF) transmission circuitry (240) on the approaching vehicle (110) is responsive to the congestion zone indication signals to transmit and receive RF signals to and from other vehicles on the guide path (102). The approaching vehicle (110) performs various collision avoidance operations as determined by the received RF signals.

Information communication system with collision avoidance

Abstract: An information communication system having several transceivers connected to a communication medium. Each transceiver connected to a collision avoidance apparatus which determines if another transceiver is preparing to transmit on the communication medium by applying a unique predetermined D.C. voltage level to the communication medium.

Apparatus and method for collision avoidance

Abstract: A collision avoidance apparatus having a voltage source producing a predetermined voltage level. A switching network within the collision avoidance apparatus is capable of alternately applying the predetermined voltage level to the communication medium and of applying the voltage level of the communication medium to a logic network. The logic network indicates if the predetermined voltage level and the voltage level of the communication medium are approximately equal.

An Analysis of the Point of Possible Collision

Abstract: The shipping industry is faced with unilateral legislation proposed by the United States of America covering navigational equipment and, in the interests of harmonization, IMCO is compiling performance specifications and carriage requirements for navigational equipment including collision avoidance systems; the establishment of type approval procedures can be anticipated. The shipowner has reservations, in respect of the need for adequate training in the use of advanced systems and the risk of navigators placing reliance on such devices as collision avoidance systems when their constant availability cannot be guaranteed.

Active beacon collision avoidance system (bcas) functional overview

Abstract: : The Active Beacon Collision Avoidance System (BCAS) is a beacon-based airborne collision avoidance system that provides for cooperative threat resolution between BCAS and conflicting aircraft and coordination with the ground ATC control function through the DABS data link. All beacon-equipped aircraft in the vicinity of the BCAS are detected. ATCRBS-equipped aircraft are interrogated using a special Mode C interrogation, DABS aircraft are initially detected passively. Those aircraft that represent a possible threat are discretely interrogated to maintain a range/altitude track. This document provides a functional overview of BCAS including operational features, a description of the avionics package, and examples of surveillance data obtained with experimental BCAS equipment. The results show that reliable surveillance performance is achieved in low and medium density airspace. (Author)

A Multi-Threat Avoidance Maneuver Generator

Abstract: Collision avoidance systems have grown in importance with the increases in both traffic density and vessel size. The main requirements on the avoidance maneuvers are that they: (1) be consistent with the rules; (2) account for ship maneuvering limitations; (3) include a return-to-original-course trajectory; and (4) take into account errors introduced by the sensors and other operating/procedural factors. A candidate multi-threat avoidance maneuver generator was formulated, implemented on a realtime processor, and validated for various ship encounter geometries with up to five ships. The maneuver generator provides the simplest possible avoidance trajectory, for each of the encountering ships, consisting of up to five turn and straight segments. A four-ship encounter scenario illustrates the effectiveness of the algorithm. This maneuver generator can be used to aid ships in avoiding collisions in a timely manner. However, further shipboard tests remain to be performed prior to the widespread operational deployment of collision avoidance systems with this capability.

Effectiveness of three electronic systems as collision-avoidance and grounding-avoidance aids

Abstract: This reporrt describes an experiment conducted at CAORF to compare shipmasters' collision-avoidance and grounding-avoidance performance in congested harbor approach situations. Comparisons were made when test subjects operated with radar, with a collision-avoidance system (CAS system), or with a collision-avoidance system with navigation option (CAS + NAV system in which channel boundaries and shoal lines are displayed with synthetic radar and collision predictive information). The results indicate that the test subjects who operated with CAS + NAV system had fewer serious incidents (collisions and groundings) than members of the other groups, who also had measurably more near misses.