Browse Topic: Aircraft collision avoidance systems
Recent advancements of electric vertical take-off and landing (eVTOL) aircraft have generated significant interest within and beyond the traditional aviation industry, and many novel applications have been identified and are in development. One promising application for these innovative systems is in firefighting, with eVTOL aircraft complementing current firefighting capabilities to help save lives and reduce fire-induced damages. With increased global occurrences and scales of wildfires—not to mention the issues firefighters face during urban and rural firefighting operations daily—eVTOL technology could offer timely, on-demand, and potentially cost-effective aerial mobility capabilities to counter these challenges. Early detection and suppression of wildfires could prevent many fires from becoming large-scale disasters. eVTOL aircraft may not have the capacity of larger aerial assets for firefighting, but targeted suppression, potentially in swarm operations, could be valuable. Most
In this article, a formation flying technique designed for a multiple unmanned aerial vehicles (multi-UAV) system to provide low-cost and efficient solution for civilian and military applications is presented. First, a modular leader-follower formation algorithm was developed to accomplish the formation flying with off-the-shelf low-cost components and sensors. Second, a proportional-integral-derivative (PID) controller was utilized for velocity control of the UAVs to maintain the tight formation. Third, a particle swarm optimization-optimized reciprocal velocity obstacles (PSO-RVO) algorithm was utilized for obstacles avoidance and collision avoidance between the UAVs while navigating, with the aid of sonar ranging sensors onboard. The formation flying algorithm developed was tested through both simulation and experiment using two quadcopters with global positioning system (GPS) signals. For the simulation, the algorithm developed was tested on a virtual quadcopter using an open
Aiming at the problem of poor robustness after the combination of lateral kinematics control and lateral dynamics control when an autonomous vehicle decelerates and changes lanes to overtake at a certain distance. This paper proposes a trajectory determination and tracking control method based on a PI-MPC dual algorithm controller. To describe the longitudinal deceleration that satisfies the lateral acceleration limit during a certain distance of lane change, firstly, a fifth-order polynomial and a uniform deceleration motion formula are established to express the lateral and longitudinal displacements, and a model prediction controller (MPC) is used to output the front wheel rotation angle. Through the dynamic formula and the speed proportional-integral (PI) controller to control and adjust the brake pressure. Based on simulation to optimize the best lane change completion time coefficient at different longitudinal lane change speeds, the relationship between the vehicle collision
Unmanned aerial vehicles (UAVs) are envisioned to operate much closer to each other in low-altitude airspace than in the conventional high-altitude air traffic system and therefore impose challenges not only to the vehicle design but also to the development of a safe yet efficient low-altitude air traffic system. NASA Ames developed an air traffic simulation tool known as Flexible engine for Fast time evaluation of Flight environments (Fe3).
Researchers developed a sensor and software application to detect and avoid energized power lines in the vicinity of unmanned aerial systems (UAS). The goal is to provide drones sufficient time and distance to react, avoid wires, and navigate follow-on maneuvers.
This SAE Aerospace Recommended Practice (ARP) sets forth design and operational recommendations concerning the human factors/crew interface considerations and criteria for vertical situation awareness displays. This is the first of two recommended practice documents that will address vertical situation awareness displays (VSAD). This document will focus on the performance/planning types of display (e.g., the map display) and will be limited to providing recommendations concerning human factored crew interfaces and will not address architecture issues. This document focuses on two types of VSAD displays: a coplanar implementation of a profile display (side projection) and a conventional horizontal map display; and a 3D map display (geometric projection). It is intended for head down display applications. However, other formats or presentation methods, such as HUDs, HMDs and 3D audio presentations may become more feasible in the future. Even though the relationship of the vertical
This study provides a simulation-based comparative analysis of the distance and time needed for long combination vehicles (LCVs) - namely, A-doubles with 28-, 33-, and 48-ft trailers - to safely exercise an emergency, evasive steering maneuver such as required for obstacle avoidance. The results are also compared with conventional tractor-semitrailers with a single 53-ft trailer. A multi-body dynamic model for each vehicle combination is developed in TruckSim® with an attempt to assess the last point to steer (LPTS) and evasive time (ET) at various highway speeds under both dry and wet road conditions. The results indicate that the minimum avoidance distance and time required for the 28-ft doubles vary from 206 ft (60 mph) to 312 ft (80 mph) and 2.3 s to 2.6 s, respectively. The required LPTS represents a 6% to 31% increase when compared with 53-ft semitrucks. When driving below 76 mph on a dry road and below 75 mph on a wet road, the 28-ft doubles exhibit LPTS and ET that are larger
Contemporary air traffic management (ATM) challenges are both (1) acute and (2) growing at rates far outpacing established ways for absorbing technological innovation. Lack of timely response will guarantee failure to meet demands. Immediately that creates a necessity to identify means of coping and judging new technologies based on possible speed of adoption. Paralleling the challenges are developments in capability, both recent and decades old. Some steps (e.g., Global Positioning System (GPS) backup) are well known and, in fact, should have progressed further long ago. Others (e.g., sharing raw measurements instead of position fixes) are equally well known and, if followed by further flight tests initiated (and successful) years ago, would have produced a wealth of in-flight experience by now if development had continued. Other possibilities (e.g., automated pilot override) are much less common and are considered largely experimental. This SAE EDGE™ Research Report is aimed at
This paper intends to present a novel optimal trajectory planning method for obstacle avoidance on highways. Firstly, a mapping from the road Cartesian coordinate system to the road Frenet-based coordinate system is built, and the path lateral offset in the road Frenet-based coordinate system is represented by a function of quintic polynomial respecting the traveled distance along the road centerline. With different terminal conditions regarding its position, heading and curvature of the endpoint, and together with initial conditions of the starting point, the path planner generates a bunch of candidate paths via solving nonlinear equation sets numerically. A path selecting mechanism is further built which considers a normalized weighted sum of the path length, curvature, consistency with the previous path, as well as the road hazard risk. The road hazard is composed of Gaussian-like functions both for the obstacle and road boundaries, which means, if one path is near the obstacle or
The bus sector is currently lagging behind when it comes to implementing autonomous systems for improved vehicle safety. However, in cities such as London, public transport strategies are changing, with requirements being made for advanced driver-assistance systems (ADAS) on buses. This study discusses the adoption of ADAS systems within the bus sector. A review of the on-road ADAS bus trials shows that passive forward collision warning (FCW) and intelligent speed assistance (ISA) systems have been successful in reducing the number of imminent pedestrian/vehicle collision events and improving speed limit compliance, respectively. Bus accident statistics for Great Britain have shown that pedestrians account for 82% of all fatalities, with three quarters occurring with frontal bus impacts. These statistics suggest that the bus forward collision warning system is a priority for inclusion in future vehicles to enhance the driver’s direct vision, and to increase reaction time for earlier
Lane-changing is a typical traffic scene effecting on road traffic with high request for reliability, robustness and driving comfort to improve the road safety and transportation efficiency. The development of connected autonomous vehicles with V2V communication provide more advanced control strategies to research of lane-changing. Meanwhile, four-wheel steering is an effective way to improve flexibility of vehicle. The front and rear wheels rotate in opposite direction to reduce the turning radius to improve the servo agility operation at the low speed while those rotate in same direction to reduce the probability of the slip accident to improve the stability at the high speed. Hence, this paper established Four-Wheel-Steering(4WS) vehicle dynamic model and quasi real lane-changing scenes to analyze the motion constraints of the vehicles. Then, the polynomial function was used for the lane-changing trajectory planning and the extended rectangular vehicle model was established to get
This document applies to laser proponents involved with the use of laser systems outdoors. It may be used in conjunction with AS4970, ARP5535, and ARP5572 and the ANSI Z136 series of laser safety standards.
AIR1608 ESTIMATION OF TOTAL ERROR IN ALTIMETRY proposes a method of estimating overall error of altimetry in order to provide a basis for safe vertical separation of aircraft.
This document presents criteria for flight deck controls and displays for Airborne Collision Avoidance Systems.
Most of today’s collision-avoidance, in-flight-entertainment (IFE), air-to-ground-communications, and other avionics systems employ electronics packaging based on the Aeronautics Radio INC (ARINC) 600 standard. Compared to the older ARINC 404 standard dating from the 1970s that defined “black box” enclosures and racks within aircraft, ARINC 600 specified a Modular Concept Unit (MCU) – the basic building block module for avionics. An ARINC 600 metal enclosure can hold up to 12 MCUs, allowing a lot of computing power to be placed in a centralized “box.” By making it possible to run numerous applications over a real-time network, ARINC 600 enabled “next generation” integrated modular avionics (IMA).
To evaluate that automated vehicle is as safe as a human driver, a following question is studied: how does an automated vehicle react under extreme conditions close to collision? In order to understand the collision avoidance capability of an automated vehicle, we should analyze not only such post-extreme condition behavior but also pre-extreme condition behavior. We present a theory to analyze the collision avoidance capability of automated driving technologies. We also formulate a collision avoidance equation on the theory. The equation has two types of solutions: response driving plans and preparation driving plans. The response driving plans are supported by response strategy on which the vehicle reacts after detection of a hazard and they are highly efficient in terms of travel time. The preparation driving plans are supported by preparation strategy on which the vehicle simulates each hazard before detecting hazards and they are safer than the response driving plans but it is not
Spinoff is NASA's annual publication featuring successfully commercialized NASA technology. This commercialization has contributed to the development of products and services in the fields of health and medicine, consumer goods, transportation, public safety, computer technology, and environmental resources.
The effectiveness of ADAS addressing property damage has an increasing impact on car manufacturers, insurers and customers, as accident avoidance or mitigation can lead to loss reduction. In order to obtain benefits, it is essential that ADAS primarily address monetarily relevant accident scenarios. Furthermore, sensor technologies and algorithms have to be configured in a way that relevant accident situations can be sufficiently avoided at reasonable system costs. A new methodology is developed to identify and configure monetarily effective parameters for ADAS during parking and maneuvering. ADAS parameters e.g. relevant accident scenarios, required crash avoidance speeds and different sensor layouts are analyzed and evaluated using a real-world in-depth accident database of insurance claims provided by Allianz Center for Technology and Allianz Automotive Innovation Center. For this purpose, a sensitivity analysis is conducted to identify most monetarily effective accident scenarios
Advanced driver assistance systems (ADAS) are improving driver and pedestrian safety, providing vehicle capabilities such as pedestrian detection, lane departure warnings, collision avoidance, and much more. The increasing use of cameras throughout vehicles is enabling many ADAS capabilities. For ADAS applications involving cameras, one critical design challenge is to move image data from the camera to the processing unit and from the processing unit to each display as quickly and efficiently as possible.
Electroimpact, in collaboration with Boeing, has developed an advanced robotic assembly cell, dubbed “The Quadbots.” Using Electroimpact’s patented Accurate Robot technology and multi-function end effector (MFEE), each robot can drill, countersink, inspect hole quality, apply sealant, and insert fasteners into the part. The cell consists of 4 identical machines simultaneously working on a single section of the Boeing 787 fuselage, two on the left, and two on the right. These machines employ “collision avoidance” a new feature in their software to help them work more synchronously. The collision avoidance software uses positional feedback from external safety rated encoders mounted to the motors on the robot. From this feedback, safe spaces, in the form of virtual boundaries can be created. Such that a robot will stop and wait if the adjacent robot is in, or going to move into its programmed work envelope. Another feature of the collision avoidance is to limit robot speeds when they are
This paper provides an analysis of how communication performance between vehicles using Dedicated Short-range Communication (DSRC) devices varies by antenna mounting, vehicle relative positions and orientations, and between receiving devices. DSRC is a wireless technology developed especially for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. A frequency band near 5.9 GHz has been set aside in the US and other countries for exploring safety and other uses for road vehicles. DSRC devices installed onboard vehicles broadcast their location using global navigation space systems (GNSS), speed, heading, and other information. This can be used to study communication performance in many scenarios including: car-following situations, rear-end crash avoidance, oncoming traffic situations, left turn advisory, head-on crash avoidance and do-not-pass warnings. Message Capture Fraction and Packet Loss Duration highlight how these measures change with distance and
On December 2015, The National Highway Traffic Safety Administration (NHTSA) published its proposal to implement U.S New Car Assessment Program (NCAP) changes covering three categories of crashworthiness, crash avoidance and pedestrian protection, beginning with the 2019 model year. The crashworthiness category included a new frontal oblique impact (OI) test protocol. The test compromises of a new Oblique Moving Deformable Barrier (OMDB), new THOR 50th percentile male (THOR-50M) anthropomorphic test device (ATD), and a new test configuration. An OMDB of 2,486 kg (5,480 lb) impacts a stationary target vehicle at a speed of 90 kph (56 mph) at an angle of 15 degrees with a 35% barrier overlap with the front end of the target vehicle. In vehicle-to-vehicle collisions, the lighter weight vehicle experience higher velocity change and higher acceleration levels, thereby, occupants in the lighter vehicle experience higher injury risk. This paper describes the analyses of a series of 31 OI
This invention, developed at NASA's Goddard Space Flight Center, was originally conceived as a high-accuracy, high-sensitivity, bi-axial Sun angle sensor, but has also been proposed for applications involving the general field of precisely measuring the direction in which light travels toward the sensor. It has applications in spacecraft navigation, formation flying in space, space beacons, and automotive collision avoidance.
Researchers at NASA’s Armstrong Flight Research Center have dramatically improved upon existing ground collision avoidance technology for aircraft. NASA’s system leverages leading-edge fighter safety technology, adapting it to civil aviation use as an advanced warning system. It offers higher fidelity terrain mapping, enhanced vehicle performance modeling, multidirectional avoidance techniques, more efficient data-handling methods, and user-friendly warning systems. The algorithms have been incorporated into an app for tablet/handheld mobile devices that can be used by pilots in the cockpit, enabling significantly safer general aviation. This will enable pilots to have access to this lifesaving safety tool regardless of what type of aircraft they are flying. The system also can be incorporated into electronic flight bags (EFBs) and/or aircraft avionics systems.
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