Showing papers on "Collision avoidance system published in 1996"

GPS collision avoidance system

Abstract: A collision avoidance system for a plurality of vehicles equipped with GPS receivers, each broadcasting current location information to other vehicles and receiving and displaying location information from other vehicles, enables a vehicle operator to be aware of the location of the other vehicles. For vehicles not equipped with GPS, and transceivers, information about location is taken from common ground control equipment such as an FAA control station and broadcast to all vehicles. In an aircraft environment, flight plans can be filed and closed out automatically.

Aircraft ground collision avoidance system and method

Abstract: A system and method for avoiding collision between objects and wingtips of an aircraft when the aircraft is on the ground includes mounting detecting devices such as a low cost radar unit and a video camera in the wingtip. These detection devices are coupled with one or more indicators to provide an operator of the aircraft such as a pilot that an imminent collision with an object is about the occur. The indication can be an audio or visual signal, either within or outside of the aircraft.

Drive assist system using stereo image recognition

Abstract: A safety vehicle using an obstacle detection system with a stereo image sensor has been developed. The stereo image sensor was chosen as a more suitable sensor, compared to a laser radar or a millimeter wave radar. The matching method adopted for this stereo system is the small area based matching to yield a distance distribution image. The road shape and solids are recognized from the distance distribution image. This safety vehicle has three functions for the "avoidance stage" proposed in ASV (advanced safety vehicle) project as follows: a collision alarm system; an autonomous collision avoidance system; and a lane-keeping alarm system. Reduction rates by this safety vehicle for a rear-end collision and a collision encountered at a intersection were estimated. It was recognized that the system was greatly effective for both type of collisions.

Development of rear-end collision avoidance system

Abstract: RCAS (rear-end collision avoidance system) has been developed as a system of ASV (advanced safety vehicle). It is a driver assist system to avoid the rear-end collision by informing the distance headway. It also has automatic braking function in case of emergency and distance warning function to the trailing vehicle. This paper describes the outline of RCAS, techniques about the preceding vehicle recognition and collision potential hazard evaluation. And experimental results about distance headway warning and collision avoidance by automatic braking are reported.

Functions and devices of Mitsubishi active safety ASV

Abstract: The Advanced Safety Vehicle (ASV) project, advocated by Japan's Ministry of Transport, was carried out from 1991 to March 1996 to promote developing safety measures for the 21st century mainly by intellectualizing vehicles. This paper introduces the main functions and devices of Mitsubishi's Active Safety ASV which employs many state-of-the-art technologies to support the driver under various traffic situations. The ASV is equipped with a multi-eye system which consists of two lane-detecting cameras, two scanning laser radar, six passive trigonometric-type sensors, and three stereo cameras, to detect surrounding traffic situations. The friendly man-machine interface consists of sophisticated indicators, warning systems, and indirect visual field systems using small video cameras. The collision avoidance system assesses the situational risk and warns the driver or performs an automatic collision avoidance if necessary.

Driving simulator tests of lane departure collision avoidance systems

Abstract: This report presents the results of a simulator-based exploratory study of Collision Avoidance System (CAS) concepts suitable for roadway departure collision avoidance. Roadway departure crashes account for significant percentages of both the total number of crashes and the number of fatal crashes in the United States. CAS support that could avert or minimize the severity of even a fraction of these crashes would prove beneficial to the driving public. The purpose of the study was to evaluate the following items from a driver-oriented perspective. Sixty-four volunteers participated at the Iowa Driving Simulator (IDS), a six-degree-of-freedom, moving-base simulator with a wide field-of-view image generation system. Sixteen of the participants were randomly assigned to serve in a control group without CAS support; the remaining 48 participants were randomly assigned to groups of 16 in each of three CAS Interface groups: auditory, haptic, or combined-modality.

Aircraft collision avoidance based on GPS position broadcasts

Abstract: The current airborne collision avoidance system provides pilots with approximate information on the relative location of nearby traffic, and with recommended escape maneuvers in the vertical plane. It relies on range measurements, and suffers from high false alarm rate. This paper studies a new collision avoidance system, which is based on periodic broadcasts of aircraft position as derived by an on-board GPS receiver. Several collision detection algorithms were evaluated by using a Monte Carlo simulation of random encounters in a free-flight environment. The algorithm selected uses the miss distance vector for both detection and avoidance. This approach can significantly improve the effectiveness of the current collision avoidance system, while lowering both the probability of false alarm and the probability of late alarm.

Dynamic Vehicle Simulation to Evaluate Countermeasure Systems for Run-Off-Road Crashes

Abstract: This paper describes the application of a time-domain simulation code that is based on a dynamic model of a drive/vehicle/countermeasure system. The systems were evaluated for their effectiveness in performing as part of a collision avoidance system.

Integrated ground collision avoidance system

Abstract: A ground collision avoidance system that is accurate and avoids nuisance warnings and displays provides an invaluable system for the preservation of life and equipment. This system improves its accuracy and performance by integrating with all other aircraft systems including guidance systems, navigation systems, digital terrain elevation databases, mission computers, and radar altimeters. Furthermore, the ground collision avoidance system provides a multiple processing path to determine numerous predicted flight paths based on a number of reasonable assumptions regarding the aircraft flight during a predetermined amount of time. By using prediction scheme a realistic estimate of the predicted flight path envelope can be determined and then this information can be used in conjunction with accurate terrain elevation databases to determine whether a ground collision condition exists. On the basis of these calculations appropriate warnings can be provided to the air crew as well as suggested maneuvers to avoid ground collision.

Concept design for a low cost cockpit display/collision avoidance system for general aviation aircraft

Abstract: DCS Corporation has developed a concept for a low cost cockpit display system to provide situations awareness and collision avoidance capabilities to the general aviation (GA) community. The GA community has the desire for an autonomous air traffic management system that will notify aircraft of possible conflicts and provide resolutions for deconfliction without relying on ground stations for air traffic control. The system concept is based on each aircraft self reporting its GPS position over a Mode S data link. A CPU onboard each aircraft processes incoming position and velocity information from cooperative traffic, analyzes potential conflicts and displays the situation via a graphical user interface (GUI). The GUI provides the situations awareness to the pilot through an easily understood representation of traffic, conflicts and resolution manoeuvres. The system could be incorporated with waypoint navigation and flight planning functions to provide a complete navigation/situational awareness system at a relatively low cost. This paper presents the original system architecture and track its progression into the current architecture.

Method of reducing the speed of a vehicle having a collision avoidance system

Abstract: A method of reducing the travelling speed of a vehicle which has a multi-cylinder, piston-type internal-combustion engine, a variably controllable valve drive and a collision avoidance system includes the following steps: continuously determining, by the collision avoidance system, an actual distance between the vehicle and a vehicle ahead and comparing the actual distance with a speed-dependent minimum safe distance; and braking the vehicle by switching over at least one of the engine cylinders to a compressor operation when the actual distance falls below a minimum safe distance.

A horizontal miss distance filter system for suppressing false resolution alerts

Abstract: The horizontal distance to avoid a collision there is provided a filter system (220), for inhibiting air traffic alert and collision avoidance system (210) providing a warning message to the pilot-resolution display (230). The horizontal distance to avoid a collision by filtration using a parabolic acceleration estimation value obtained from (11) from the track (10), having a non-zero level for distinguishing intrusion aircraft to avoid a collision (110) distance. According to the distance data supplied from the parabola tracker calculated horizontal distance to avoid a collision based on an azimuth track (22) based on the horizontal azimuth angle of collision avoidance provided by the distance comparison. The two calculated horizontal level to avoid collision of the projection distance to avoid a collision, it is compared with a predetermined threshold distance smaller. Any level to avoid a collision projection distance is greater than the threshold of resolution intrusion alarm aircraft are prohibited, unless it is determined in the plane crash included one for maneuver.

Road lane recognition system for RCAS

Abstract: Road-lane recognition is one of the key technologies utilized in the intelligent transport system, a sophisticated road traffic information system in Japan. In this paper, we take a general view of road-lane recognition methods that use image processing with reference to the recognition frames of capturing, conversion, classification and interpretation. While these recognition methods employ a bottom-up processing approach, we believe a top-down processing approach based on prior knowledge of the recognition target will play a more important role in the future. One of the purposes of road-lane recognition in rear-end collision avoidance system (RCAS) is to determine whether the vehicle in front is in the same lane or not. As a solution to that question, we introduce a network type fusion method, which divides a recognition process into modules connected in a network and then uses the changes of state obtained in mutual tests to determine the vehicle's position relative to the road lane.

Development of performance specifications for collision avoidance systems for lane change, merging, and backing. task 5: crash countermeasure technology investigation

Abstract: An investigation of the technologies that are important for crash countermeasures against lane change and merging accidents has been conducted. The sensor technologies have been limited to radar and lidar because of the relatively long ranges required for high closing velocity accident avoidance. The state of the art of digital signal processors has also been determined. The other key technology, namely, display technology is being investigated in other studies. The preliminary performance specifications that were developed earlier as part of this program have been utilized as a benchmark which the capability of each technology has been measured against. For sensor technologies, the ability to detect the specified targets over the defined volume in space is a key performance goal. Equally important is the immunity from both false and nuisance alarms. Issues concerning public safety from radiation exposure, and mitigation of interference have also been addressed. In the area of processing, a set of requirements for processor speed, architecture, and memory was derived from an estimate of the computations needed to accomplish the detection of targets and the further calculations necessary to determine their speeds and discriminate against non-threatening or inappropriate targets. The results indicate that both radar and lidar technology are capable of performing the detection function and both have enough waveform flexibility to mitigate against interference. Both can be utilized in a manner consistent with the prevailing safety standards and both have solid state implementations that could lead to low-cost, highly reliable components when the demand becomes more real. Processors are also advancing a rapid rate. Small low cost processors capable of performing the necessary computations in a timely manner already exist and progress continues towards faster and cheaper units. The overall cost of the crash countermeasure system cannot yet be determined; for one thing, it will vary in accordance with its level of crash avoidance capability.

Real-Time Sonar Classification for Autonomous Underwater Vehicles.

Abstract: : The Naval Postgraduate School autonomous underwater vehicle (AUV) Phoenix did not have any sonar classification capabilities and only a basic collision avoidance system. The Phoenix also did not have the capability of dynamically representing its environment for path planning purposes. This thesis creates a sonar module that handles real time object classification and enables collision avoidance at the Tactical level. The sonar module developed communicates directly with the available sonar and preprocesses raw data to a range - bearing data pair. The module then processes the range - bearing data using parametric regression to form line segments. A polyhedron building algorithm combines line segments to form objects and classifies them based on their attributes. When the Phoenix is transiting, the classifying algorithm detects collision threats and initiates collision avoidance procedures. The result of this thesis is a fully implemented sonar module on the Phoenix. This module was tested in a virtual world, test tank and in the first ever sea-water testing of the Phoenix. The sonar module has demonstrated real time sonar classification, run time collision avoidance and the ability to dynamically update the representation of the unknown environment. The sonar module is a forked process written in the 'C' language, functioning at the Tactical level. Source code and output from an actual Phoenix mission displaying the object classification of the sonar module are included.

Development of a collision avoidance system considering the navigation plan

Abstract: In this paper, a collision avoidance system considering the navigation plan is developed. As a standard of judgment for collision avoidance, the degree of collision risky by fuzzy reasoning with input variables of TCPA and DCPA is used, and the navigation plan is made using A* search method. The simulation results show that the collision avoidance system taking into consideration the navigation plan takes safer and smoother actions than the system without taking the navigation plan into consideration.

Requirements for coordination and the application of an automatic collision avoidance system.

Abstract: This paper is concerned with the legislative change which would have to take place if an automatic collision avoidance system were to be implemented. The principle of complementary action, and the role of coordination in achieving that action is considered. Current collision avoidance practice is discussed, noting the coordination attributes of the International Regulations for the Prevention of Collision at Sea, and the responsibility placed on the mariner by the regulations. The processing element of an automatic collision avoidance system is considered in the light of current judicial practice. The paper concludes that the implementation of an automatic collision avoidance system is incompatible with the current collision regulations and the supporting judiciary. It is suggested that successful implementation will require the recognition of a discrete rule base.

Collision avoidance system performance specification for lane change, merging and backing: phase i results and future plans

Abstract: The objective of the National Highway Traffic Safety Administration (NHTSA)-funded study at TRW is to determine the performance specifications of collision avoidance systems (CASs) for lane change, merging, and backing. This four-year effort was initiated in the summer of 1993 and is being carried out in three phases. Phase I (completed) involved four tasks: crash problem analysis, functional goals establishment, existing hardware system testing, and preliminary performance specifications development. In Phase II advanced technologies potentially applicable to crash countermeasures are being evaluated and a testbed developed. Phase III will involve construction of the testbed and refining of the preliminary performance specifications obtained in Phase I. This paper summarizes Phase I results, which culminated in the preliminary performance specifications for a lane change CAS.

Control and validation of expert tasks for a collision avoidance system

Abstract: In order to improve car driving security, there have been a lot of developments by car constructors: air bag, seat belt. All of them are made to reduce human physical damage in case of accident but do not prevent the accident from taking place. We describe our work which forms part of the European project Prometheus which aims to propose a real time collision avoidance system embedded in a car. In this paper we discuss particularly the decision module which warns the driver against an eventual collision. For this we have chosen to use an expert system.

Taxonomy and size assessments for forward impact crashes applicable to forward collision warning systems

Abstract: This paper presents size assessments and statistical descriptions of specific categories of forward impact collisions for which a collision avoidance system may prove to be effective. The paper discusses the following: the database from which these estimates are derived; the categories of crashes this system may impact; the population of each crash category; damage or loss associated with the crash; which crashes are the most hazardous; costilness of the crashes; and velocity distributions derived from the database.