Showing papers on "Collision avoidance published in 1978"

A differential game approach to collision avoidance of ships

Abstract: A differential game method has been developed which divides the state-space into two regions. In one region ship P2 can always cause a collision, in the other region ship P1 can prevent a collision, provided it uses an appropriate strategy. In a future publication slightly different sets of ships will be considered such as to get a feeling for the sensitivity of the collision avoidance capacities w.r.t. the three parameters which characterize a ship (i.e. length, velocity, maximum turnrate).

The Analysis of Dynamically Interactive Systems (Air Combat by the Numbers).

Abstract: : Dynamically interactive systems are characterized by a mutual interaction in which each of the systems responds to each of the other systems according to its perception of the problem and its perceived methods of achieving a goal or objective. Examples of the problem class are: Aircraft collision avoidance; Destroyer/Submarine Encounter; Air Combat; and The Child's Game of Tag. The analysis of dynamically interactive systems is approached from a non-deterministic viewpoint.

Ipc design validation and flight testing

Abstract: A series of flight tests were conducted to evaluate the collision avoidance system known as Intermittent Positive Control (subsequently re-named Automatic Traffic Advisory and Resolution Service, ATARS). These tests involved both professional test pilots and subject pilots selected from the aviation community. This report includes analysis of the collision avoidance algorithm, pilot visual acquisition performance, and pilot reaction to avoidance instructions. (Author)

Collision avoidance behaviour and uncertainty

Abstract: A review of world-wide collision statistics of the past 20 years indicates that, in spite of the expanded use of radar, the over-all collision rate remains alarmingly high. Because of radar's less than perfect record for preventing ship collisions, development of various types of collision avoidance systems has taken place. The implied promise in this development is that the computer-aided radar will provide a lasting answer to the collision avoidance problem. Motivated by such considerations, an experiment was conducted to the United States Maritime Administration's newly completed Computer Aided Operations Research Facility (CAORF). The purpose was to study the human dynamics involved in collision avoidance behaviour on the bridge of a modern merchant ship, and to evaluate the advantages of a collision avoidance system (C.A.S). During the course of the experiment it was observed that test subjects made a large number of left turns when operating with radar and C.A.S. This paper presents preliminary results of an investigation into the potential confusion caused by such non-standard maneuveres when operating under the following conditions: (i) Visual only--no electronic aids,(ii) Radar, (iii) Collision avoidance system.

Automatic Control of Underway Replenishment Maneuvers in a Random Sea

Abstract: This paper describes a hybrid computer simulation of two ships performing replenishment operations in random seas Such operations present collision hazards due to the nonlinear interaction forces and moments which result from close proximity maneuvering while underway Maneuvers are simulated to demonstrate automatic controller performance during station-keeping, station-changing, and the approach and breakaway phases of typical underway replenishment (UNREP) operations Results indicate that automatic control should be considered as a possible solution to the UNREP collision avoidance problem

Safe navigation, getting down to basics

Abstract: Recent collisions and strandings have underlined the real need to improve standards of navigation and reduce the number of collisions. These suggestions are intended to be basic, because the entire concept of good seamanship is founded on carrying out basic precepts conscientiously and in developing the necessary good habits required for safe navigation and collision avoidance. Order from NSFI as No. 17506.

Obstacle protection with unmanned vehicles

Abstract: Powered vehicles in industrial environments have long been accepted and their safety considerations have become standard. Low-speed, unmanned vehicles are now being introduced to office and similar situations, requiring a new approach to safety considerations. This paper describes a low-frequency radio system for collision avoidance.

A student-designed automotive collision avoidance system

Abstract: A receiver-transmitter system at 99 MHz is energized by a shock activated switch to provide warnings of collision, emergency vehicles, or other road hazards. The system was designed and constructed as part of a senior design sequence. It was intended to be simple and reliable, and, when translated into modern integrated circuit technology, it can be installed at a low cost per vehicle. It provides advantages over radar braking in that it is practically feasible and much less expensive. It has advantages over other approaches in that it can be used in the daytime or at night and in any weather.

Applications of Remote Sensing by Conventional Radars

Abstract: There is a widespread availability of surveillance radars used primarily for navigation and collision avoidance, apart from larger equipments used for air traffic surveillance and defence purposes. Examples of the use of these radars for sensing air-sea interactions are given with comments on interpretation of the displays.

Perseveration effects in detection tasks with correlated decision intervals. [applied to pilot collision avoidance]

Abstract: An investigation of the behavior of the human decisionmaker is described for a task related to the problem of a pilot using a traffic situation display to avoid collisions. This sequential signal detection task is characterized by highly correlated signals with time varying strength. Experimental results are presented and the behavior of the observers is analyzed using the theory of Markov processes and classical signal detection theory. Mathematical models are developed which describe the main result of the experiment: that correlation in sequential signals induced perseveration in the observer response and a strong tendency to repeat their previous decision, even when they were wrong.