Browse Topic: Global positioning systems (GPS)
There are certain situations when landing an Advanced Air Mobility (AAM) aircraft is required to be performed without assistance from GPS data. For example, AAM aircraft flying in an urban environment with tall buildings and narrow canyons may affect the ability of the AAM aircraft to effectively use GPS to access a landing area. Incorporating a vision-based navigation method, NASA Ames has developed a novel Alternative Position, Navigation, and Timing (APNT) solution for AAM aircraft in environments where GPS is not available.
A new scientific technique could significantly improve the reference frames that millions of people rely upon each day when using GPS navigation services, according to a recently published article in Radio Science.
Radio frequency (RF) and microwave signals are integral carriers of information for technology that enriches our everyday life – cellular communication, automotive radar sensors, and GPS navigation, among others. At the heart of each system is a single-frequency RF or microwave source, the stability and spectral purity of which is critical. While these sources are designed to generate a signal at a precise frequency, in practice the exact frequency is blurred by phase noise, arising from component imperfections and environmental sensitivity, that compromises ultimate system-level performance.
In the early 2010s, LightSquared, a multibillion-dollar startup promising to revolutionize cellular communications, declared bankruptcy. The company couldn't figure out how to prevent its signals from interfering with those of GPS systems. Now, Penn Engineers have developed a new tool that could prevent such problems from ever happening again: an adjustable filter that can successfully prevent interference, even in higher-frequency bands of the electromagnetic spectrum.
In the early 2010s, LightSquared, a multibillion-dollar startup promising to revolutionize cellular communications, declared bankruptcy. The company couldn’t figure out how to prevent its signals from interfering with those of GPS systems.
RMIT University’s Arnan Mitchell and University of Adelaide’s Dr. Andy Boes led an international team to review lithium niobate’s capabilities and potential applications in the journal Science. The team is working to make navigation systems that help rovers drive on the Moon — where GPS is unable to work — later this decade.
A fundamentally different approach to wind estimation using unmanned aircraft than the vast majority of existing methods. This method uses no on-board flow sensor and does not attempt to estimate thrust or drag forces. Embry-Riddle Aeronautical University, Daytona Beach, Florida Traditionally, remotely piloted aircraft systems, or drones, have used onboard flow sensors to measure wind effects, producing in-flight metrics on which operators rely. Leveraging GPS instead, however, might provide more robust measurements, leading to safer, more efficient flights, according to Embry-Riddle Aeronautical University researchers. As most drones weigh less than 55 pounds, even mild gusts of wind can disrupt their flight, which makes finding creative solutions to monitor and predict hyperlocal weather conditions essential to flying without disruption or unplanned landings.
The safety of students during transportation on school buses is a paramount concern for both parents and schools. Although GPS (Global Positioning System) tracking systems are commonly used, they are limited in their ability to identify which students are on board. To ensure the safety and security of the students, this paper proposes a student authentication system based on facial recognition, people counter along with GPS vehicle tracking. This is intended to explore the advantages of these three technologies combined together for student authentication, the implementation process, and how it can improve the safety of school bus transportation.
Researchers have developed an algorithm that can “eavesdrop” on any signal from a satellite and use it to locate any point on Earth, much like GPS. The study represents the first time an algorithm was able to exploit signals broadcast by multi-constellation low-Earth orbit (LEO) satellites, namely Starlink, OneWeb, Orbcomm, and Iridium.
Northrop Grumman Woodland Hills, CA 224-200-7539
ABSTRACT Geotechnical site characterization is the process of collecting geophysical and geospatial characteristics about the surface and subsurface to create a 3-dimensional (3D) model. Current Robot Operating System (ROS) world models are designed primarily for navigation in unknown environments; however, they do not store the geotechnical characteristics requisite for environmental assessment, archaeology, construction engineering, or disaster response. The automotive industry is researching High Definition (HD) Maps, which contain more information and are currently being used by autonomous vehicles for ground truth localization, but they are static and primarily used for navigation in highly regulated infrastructure. Modern site characterization and HD mapping methods involve survey engineers working on-site followed by lengthy post processing. This research addresses the shortcomings for current world models and site characterization by introducing Site Model Geospatial System
This SAE Aerospace Standard (AS) defines implementation requirements for the electrical interface between: a Aircraft carried miniature store carriage systems and miniature stores b Aircraft parent carriage and miniature stores c Surface-based launch systems and miniature stores The interface provides a common interfacing capability for the initialization and employment of smart miniature munitions and other miniature stores from the host systems. Physical, electrical, and logical (functional) aspects of the interface are addressed.
While a majority of transportation and mobility solutions rely on in-vehicle sensors and the availability of the global positioning system (GPS) for absolute localization, alternate paradigms leveraging smart infrastructure have started becoming a viable solution for localization without needing GPS. However, the majority of approaches involving smart infrastructure require a means for wireless communication. In this article, we describe a novel method that can accurately localize the vehicle without using GPS and wireless communication by leveraging embedded digital and analog information on the roadside signage. The embedded information consists of a digital signature which can be used to cross-reference the ground truth (GT) location of the signage, as well as geometric information of the signage. This information is directly leveraged by on-vehicle sensors to generate absolute localization information. Specifically, the smart infrastructure consists of signage that is visible
Nowadays, real-world emissions and consumption behaviour of Light Duty (LDV) and Heavy Duty (HDV) vehicles are key factors in achieving greenhouse gas (GHG) targets. With the introduction of EURO VI in 2013 there were already low emission levels and real fuel consumption of new HDV vehicles. Furthermore, the available public literature regarding fuel consumption of European HDV vehicles is not very extensive. Hence, the development of an experimental activity related to HDVs real consumption measurement and the subsequent data analysis can be considered in this field. To this end, the fuel consumption data of four rear-loader garbage Diesel trucks, managed by a multiservice company in the Southern Italy, were collected during real use. Vehicles in pairs have different technical characteristics (i.e. engine capacity and maximum load capacity of the garbage). In this paper, we describe the methodology implemented to analyze the complete set of data (collected through questionnaires) from
ABSTRACT Leader-follower autonomous vehicle systems have a vast range of applications which can increase efficiency, reliability, and safety by only requiring one manned-vehicle to lead a fleet of unmanned followers. The proper estimation and duplication of a manned-vehicle’s path is a critical component of the ongoing development of convoying systems. Auburn University’s GAVLAB has developed a UWB-ranging based leader-follower GNC system which does not require an external GPS reference or communication between the vehicles in the convoy. Experimental results have shown path-duplication accuracy between 1-5 meters for following distances of 10 to 50 meters. Citation: K. Thompson, B. Jones, S. Martin, and D. Bevly, “GPS-Independent Autonomous Vehicle Convoying with UWB Ranging and Vehicle Models,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022.
While stereo cameras and computer vision guide Deere's “limited release” 8R autonomous tractor, Bear Flag's lidar tech will augment future machines. Q&A with Deere's Joe Liefer John Deere got “really serious” about autonomy in 2019, according to Joe Liefer, senior product manager of autonomy at John Deere Intelligent Solutions Group. Three years later - after forming an in-house development team and acquiring some tech-startup expertise - the machinery maker revealed a fully autonomous tractor at CES 2022 that it claims is ready for large-scale production. Based on Deere's 8R tractor, the machine combines a TruSet-enabled chisel plow, GPS guidance system, advanced AI and six pairs of stereo cameras that enable 360-degree obstacle detection and distance calculation. The autonomous 8R tractor also continuously checks its position relative to a geofence and is accurate to within less than 1 inch (25 mm), Deere claims. Farmers monitor and control it from a smartphone app.
The GPS Radio Occultation and Ultraviolet — Colocated (GROUP-C) experiment was originally conceived in 2010 as a CubeSat mission, combining a compact GPS occultation receiver and high-sensitivity far-ultraviolet (FUV) photometer experiment to be flown as a Space Test Program experiment. The concept was to incorporate a commercial off-the-shelf GPS receiver and a small second-generation FUV photometer to replicate the space weather portion of the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC/FORMOSAT-3) mission at lower cost. In the same timeframe, the Air Force Space and Missile System Center initiated the Space Environment NanoSatellite Experiment (SENSE) to demonstrate several CubeSat technologies for space environment sensing, which included the Compact Tiny Ionospheric Photometer (CTIP) and the Compact Total Electron Content Sensor (CTECS).
NASA’ Deep Space Network (DSN), a sort of GPS system for space, relies on atomic clocks for extreme accuracy. Any modern navigation system must accurately time radio signals to triangulate a location. But the need for accuracy is even higher in space, where great distances can compound even tiny errors.
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