Browse Topic: Radar

Items (281)
Find
Flight Test Assessment of Scalable Low-Level Mission Task ElementsF-0081-2025-01405/20/2025
Low-level flight, defined by high-speed operations near terrain, represents a significant challenge in military rotorcraft missions while providing strategic advantages, such as radar evasion and heightened surprise. Recent conflicts highlight the urgent need for advanced low-level flight capabilities in the design of new rotorcraft. The close proximity to ground obstacles, combined with the complexities of piloting, necessitates precise control and robust handling qualities to prevent accidents. However, existing handling quality standards, such as MIL-DTL-32742, reveal limitations in assessing low-level maneuvers. Given the diverse array of new rotorcraft designs, driven by initiatives like the U.S. Army's Future Vertical Lift and NATO's Next Generation Rotorcraft Capabilities, a customized handling qualities evaluation for each design is impractical. In response, a performance-driven strategy has been implemented, scaling Mission Task Elements to align with aircraft performance capabilities. This approach identifies handling quality gaps across the Operational Flight Envelope, concentrating on the aircraft’s effectiveness in achieving task success under varied conditions. Prior simulator studies validate the effectiveness of this method for assessing different configurations. This paper presents flight test results using DLR's ACT/FHS research helicopter, confirming a set of scalable Mission Task Elements developed at DLR's AVES and NASA's VMS simulators. Pilots utilized a Head-Mounted Display for task cueing, eliminating the need for physical infrastructure. The Mission Task Elements proved suitable for evaluating the low-level handling qualities of the ACT/FHS. Although the provided Head-Mounted Display facilitated Handling Qualities evaluations, it encountered some hardware limitations. The scaling for different airspeeds met pilot expectations, and wind compensation functioned as anticipated, enhancing the independence of flight tests from environmental conditions. These findings lead to recommended updates for task descriptions and course cueing requirements, confirming desired performance tolerances.
Jusko, Tim, Berger, Tom, Walko, Christian
VTOL UAS Auto-recovery Using A Tested Long-Term Motion Prediction Method to define the Deck EnvironmentF-0080-2024-10585/7/2024
Launch, recovery, and deck handling operational performance on smaller ship platforms like Corvettes, Frigates and Destroyers are qualified as the most challenging tasks in the UAS ship-deployment of a VTOL Uncrewed Air System (UAS). One of the main hurdles is the random nature of seaway-created deck motions coupled with ship structure disturbed air wake patterns. The MoD has supported a range of work aimed at bringing Quiescent Period Prediction (QPP) technology to fruition. QPP firstly requires Wave Profiling RADAR to measure the sea wave system out to approximately 2km in the region around a vessel. Secondly these measurements are employed in a wave propagation model to predict the actual wave forces acting on a vessel. Using the wave predictions as inputs to a vessel model makes possible to predict the actual (deterministic as opposed to statistical) motions of a vessel. Wave systems naturally alternate groups of large waves with smaller waves, this property, combined with the predictive ability, allows to identify the quietest (most quiescent) periods in which to conduct wave limited naval operations. Naval mission planners in the Royal Navy, and elsewhere in the World, appreciate the need to maintain rapid, but safe, deck tempo. The fundamental concept is to measure remote sea surface profiles to predict the future wave forces acting upon a vessel. The objective is to expand ship operating deck limits to approximately Sea State 6+. The deck definitions generally empirically measured by using standard rating scales, are replaced by instrumented devices reporting the status of the deck prior to touch-down. In this paper, a thorough discussion describing the QPP deck measuring devices designed to replace piloted cueing is provided. Theory, previous simulation studies and current at-sea testing along with data results, are also discussed. To conclude, the interface of the deck measuring device into the next version of the UK UAS system, is provided. The results of the RADAR trial indicated that the RADAR data was reliable, with the RADAR images matching the physical map. The two-dimensional surface plot showed both the RADAR blocking fence along with an additional target. An additional observation concerning the operation over the deck whilst the ship is experiencing a quiescent ship motion period. The coupled secondary effect documents minimized air wake confusion. This is owing to fewer ship structure excursions into and out of the air flow. To better define deck airflow around the ship the integration of a Doppler LIDAR instrumented federate is proposed. This is meant to predict the future vessel air wake and look for quiescent periods in this paralleling the vessel motion QPP technique.
Ferrier, Bernard, Christmas, Jacqueline, Belmont, Michael, Watson, RN, Commander Brad
Piloted Simulation Evaluation of MTEs for the Assessment of Low-Level Handling QualitiesF-0080-2024-10485/7/2024
This study introduces three new proposed Mission Task Elements (MTEs) - "Big Air", "Giant Slalom", and "Super Combined" - aimed at evaluating handling qualities during low-level and high-speed flight profiles. These MTEs are designed to reflect operational task elements critical in military engagements, particularly where rotorcraft capabilities in evading radar detection and maneuvering at high speeds are paramount. Utilizing piloted simulations with four generic rotorcraft configurations under various flight control laws, the MTEs' effectiveness in exposing aircraft characteristics and handling deficiencies is systematically assessed. The evaluation, conducted with a diverse group of pilots, underscores the MTEs' relevance to real-world scenarios and their robustness in handling qualities assessment across different rotorcraft designs. The study reveals that while some configurations exhibit consistent Level 1 Handling Qualities Ratings (HQRs), others show varied performance, particularly when integrating additional means of velocity control, such as pusher propellers or velocity hold modes. Findings suggest modifications to current evaluation frameworks to better accommodate the dynamic operational requirements of future vertical lift platforms.
Jusko, Tim, Berger, Tom
Object Detection and Tracking for Autonomous Vehicles in Adverse Weather Conditions2021-01-00794/6/2021
Object detection and tracking is a central aspect of perception for autonomous vehicles. While there has been significant development in this field in recent years, many perception algorithms still struggle to provide reliable information in challenging weather conditions which include night-time, direct sunlight, glare, fog, etc. To achieve full autonomy, there is a need for a robust perception system capable of handling such challenging conditions. In this paper, we attempt to bridge this gap by proposing an algorithm that combines the strength of automotive radars and infra-red thermal cameras. We show that these sensors complement each other well and provide reliable data in poor visibility conditions. We demonstrate the advantages of a thermal camera over a visible-range camera in these situations and employ YOLOv3 for object detection. The proposed system utilizes a modified Track-Oriented Multiple Hypothesis Tracking (MHT) algorithm which uses data from these sensors to keep track of the surrounding vehicles. The modifications in the well-known MHT algorithm were introduced in order to curb the exponential growth of possible hypotheses and consequently reduce the computational time without loss of any critical information. To validate the system, we provide a real-time implementation on an urban dataset collected at the Texas A&M University.
Bhadoriya, Abhay Singh, Vegamoor, Vamsi Krishna, Rathinam, Sivakumar
Dynamically Adjustable LiDAR with SPAD Array and Scanner2021-01-00914/6/2021
An important function of an Automated Driving (AD) system is to detect objects including vehicles and pedestrians on the road. Typical devices for detecting those objects include cameras, millimeter-wave RADAR, and light detection and ranging (LiDAR). LiDAR uses the flight time of a short-wavelength electromagnetic wave. Because of that LiDAR is expected to find even small objects such as tire fragments on a road in high resolution. The detection performance required for LiDAR depends on the operational design domain (ODD). For example, while a vehicle is travelling at high speeds, LiDAR needs to detect apparently small objects at long distances, and while it is travelling at low speeds, LiDAR has to detect objects over a wide angular range. Conventional LiDAR is developed to satisfy all requirements, providing performance including detection distance, resolution, and angle of view tends to expose issues such as cost and size when it is mounted onboard. To solve these problems, we have built LiDAR with a new structure consisting of an originally developed light receiving unit and scanning unit, which are the main components. The light receiving units uses an array of high-sensitivity single-photon avalanche diodes (SPADs). Its vertical resolution can be selected by changing the number of SPADs per pixel. The scanning unit has introduced a reciprocal motion system, which enables dynamically choosing the range and speed of scanning, with the range of scanning 100 ° or wider. With these mechanisms, it is possible to select a high-resolution and narrow-angle mode when detecting small objects at long distances, and low-resolution and wide-angle mode for detecting many objects at short distances. Therefore, the LiDAR can adjust its performance dynamically according to driving scenes. We have confirmed that our LiDAR is effective for detecting objects under various conditions.
Nakajima, Masato, Hata, Takehiro, Ueno, Akifumi, Ozaki, Noriyuki, Mizuno, Fumiaki, Kashiwada, Shinji, Yanai, Kenichi
DA-IVE: MLP Based Data Association Method for Instantaneous Velocity Estimation Using Multi-Radar: An Experimental Validation Study2021-01-00924/6/2021
This paper describes a novel Multi-Layer Perceptrons (MLP) learning-based association algorithm that is used in conjunction with an Instantaneous Velocity Estimator (IVE) to estimate the velocity of a surrounding vehicle using multi-radar sensors. The IVE algorithm requires at least two targets to be able to provide a velocity estimate. The approach suggested in this paper performs three stages of filtering on a list of targets available for the association to a given track. The algorithm identifies the one pair of targets that will provide the best instantaneous velocity estimation from all possible pairs. The three stages of filtering described ahead are, I - Semantic gating, II - MLP scoring, and III - Algebraic scoring. The IVE algorithm performs linear regression on the pair of targets it is finally provided to come up with a velocity estimation. This research also describes a novel method of labeling radar targets for use in the training of the neural network in association stage II. A thorough analysis of the correlation between a radar target’s quality and attributes is performed and presented here. The performance of the proposed algorithm is evaluated using real-world data collected through the ZF Automated Driving prototype vehicle.
Shakibajahromi, Bahareh, Krishnan, Anirudh Sarathy, Ati, Dilip, Jabalameli, Amirhossein, Kanzler, Steven, Shayestehmanesh, Saeed
Research on Tracking Algorithm for Forward Target-Vehicle Using Millimeter-Wave Radar2020-01-07024/14/2020
In order to solve such problems that the millimeter-wave radar is of large computation, poor robustness and low precision of the target tracking algorithm, this paper presents an algorithmic framework for millimeter-wave radar tracking of target-vehicles. The target measurement information outside the millimeter- wave radar detection range is eliminated by the data plausibility judgment method based on the millimeter-wave radar detection parameters. Target clustering is made using Manhattan distance, to eliminate clutter interference and cluster multiple target measurements into one. The data association is made by use of nearest neighbor to determine the correspondence between information received measured by the radar and the real target. The vehicle is the key detection target of the vehicle millimeter-wave radar during road driving. These target-vehicles generally have no vertical movement or small moving speed in the vertical direction, so only the movement of the target-vehicle in the XY plane needs to be considered. Since the target-vehicle motion state has the characteristics of small mobility, a constant acceleration model is established based on the millimeter-wave radar motion coordinate system to describe the motion state of the front target-vehicle. The motion state are tracked and optimized by the algorithm of improved adaptive extended Kalman filter (IAEKF), because it is difficult to determine the statistical property of its measurement noise. A differential position system is formed by installing a base station on the ground and RT3000s on the ego-vehicle and target-vehicle, respectively. Differential Position System is formed by installing Base Station on the ground and high-precision inertial navigator RT3000s and RT-XLANs on the ego-vehicle and target-vehicle, respectively. By use of the differential position system, with effective communication, the relative distance and speed information between both vehicles can be obtained in real time to verify the accuracy of the millimeter-wave radar target tracking algorithm. Results show the proposed algorithm is feasible and of high estimation accuracy.
Song, Shiping, Wu, Jian, Yang, Yu, He, Rui, Chen, Xuesong, Li, Xin
System Allows Diabetics to Monitor Blood Sugar Without Drawing BloodTBMG-357901/1/2020
Radar and artificial intelligence (AI) technologies have been combined in a system that detects changes in glucose levels without the need for painful finger pricks. The technology could be a smart watch that continuously monitors glucose.
Software-Defined Analog Filters: A Paradigm Shift in Radio Filter Performance and Capability19AERP12_0512/1/2019
Among the most abundant components in all wireless system designs, analog RF filters are used to block interference from various internal and external sources. Limited spectrum divided among an ever-increasing number of users is further driving the need for these ubiquitous but in some ways anachronistic devices. Currently, interference is quite common among cellular base stations, satellite systems, radar installations, and other types of access and backhaul communications systems. Traditional filters are unable to cope with the requirements; in many cases, most often due to insufficient guard bandf. For example, in some international locales, LTE base stations and satellite receivers share the L-band frequencies. At around 3.5 GHz, 5G operators, CBRS radios, and military radars are trying to co-exist. To address this in-band interference, a new, tunable filtering technology is entering the marketplace, uniquely blending the best of both analog and digital technologies.
Software-Defined Analog Filters: A Paradigm Shift in Radio Filter Performance and CapabilityTBMG-3566512/1/2019
Among the most abundant components in all wireless system designs, analog RF filters are used to block interference from various internal and external sources. Limited spectrum divided among an ever-increasing number of users is further driving the need for these ubiquitous but in some ways anachronistic devices. Currently, interference is quite common among cellular base stations, satellite systems, radar installations, and other types of access and backhaul communications systems. Traditional filters are unable to cope with the requirements; in many cases, most often due to insufficient guard bandf. For example, in some international locales, LTE base stations and satellite receivers share the L-band frequencies. At around 3.5 GHz, 5G operators, CBRS radios, and military radars are trying to co-exist. To address this in-band interference, a new, tunable filtering technology is entering the marketplace, uniquely blending the best of both analog and digital technologies.
Low-Bandwidth Radar Technology Provides Improved Detection of ObjectsTBMG-3569012/1/2019
Radar technologies were originally designed to identify and track airborne military targets. Today, they're more often used to detect motor vehicles, weather formations, and geological terrain. Until now, scientists believed that radar accuracy and resolution are related to the range of frequencies or radio bandwidth used by the devices. A new approach inspired by optical coherence tomography (OCT) requires little to no bandwidth to accurately create a high-resolution map of a radar's surrounding environment. The new technology has numerous applications, especially with respect to the automotive industry.
Using 24 GHz Doppler Radar Sensors for Noncontact Human Vitals DetectionTBMG-3562312/1/2019
Health and wellness monitoring is a primary way to manage personal health and awareness for a healthy lifestyle. Many wearable activity tracking devices, smart watches, and smartphone applications collect and analyze data from bodily sources. Other types of devices used to monitor vital signs can help the wearer manage health issues but can limit the wearer’s mobility or cause discomfort if worn continuously. These restrictions have prompted a growing interest in developing noncontact, wireless devices to detect vital signs, especially for people who are unconscious, sleeping, very young, elderly, or infirm. This article explains why 24 GHz Doppler radar sensors are useful for such devices and highlights some of the features suitable for meeting these applications.
Autonomous Multi-Sensor Maritime Awareness SystemTBMG-3536410/1/2019
BIRD Aerosystems Herzliya, Israel
Shape-Shifting Origami Could Help Antenna Systems Adapt On-the-FlyTBMG-351079/1/2019
Conventional reconfigurable electrical and radio frequency (RF) structures commonly used in applications involving real-time reconfigurability in response to fast varying operational scenarios require specialized substrates or complex electrical circuits. Origami-based RF reconfigurable components and modules offer a solution with unique properties. First, they enable re-configurability over continuous-state ranges (as opposed to discrete states). Second, they do not require specialized mechanical support for multilayer frequency-selective surface structures. Moreover, deployable origami-based RF structures can achieve large surface re-configurability ratios from folded to unfolded states. Finally, these structures allow for independent control of multiple figures of merit: bandwidth, frequency of operation, and angle of incidence.
Radar Detection of High Concentrations of Ice Particles - Methodology and Preliminary Flight Test Results2019-01-20286/10/2019
High Ice Water Content (HIWC) has been identified as a primary causal factor in numerous engine events over the past two decades. Previous attempts to develop a remote detection process utilizing modern commercial radars have failed to produce reliable results. This paper discusses the reasons for previous failures and describes a new technique that has shown very encouraging accuracy and range performance without the need for any modifications to industry’s current radar design(s). The performance of this new process was evaluated during the joint NASA/FAA HIWC RADAR II Flight Campaign in August of 2018. Results from that evaluation are discussed, along with the potential for commercial application, and development of minimum operational performance standards for future radar products.
Harrah, Steven, Strickland, Justin, Hunt, Patricia, Proctor, Fred, Switzer, George, Ratvasky, Thomas, Strapp, J. Walter, Lilie, Lyle, Dumont, Christopher
Summary of the High Ice Water Content (HIWC) RADAR Flight Campaigns2019-01-20276/10/2019
NASA and the FAA conducted two flight campaigns to quantify onboard weather radar measurements with in-situ measurements of high concentrations of ice crystals found in deep convective storms. The ultimate goal of this research was to improve the understanding of high ice water content (HIWC) and develop onboard weather radar processing techniques to detect regions of HIWC ahead of an aircraft to enable tactical avoidance of the potentially hazardous conditions. Both HIWC RADAR campaigns utilized the NASA DC-8 Airborne Science Laboratory equipped with a Honeywell RDR-4000 weather radar and in-situ microphysical instruments to characterize the ice crystal clouds. The purpose of this paper is to summarize how these campaigns were conducted and highlight key results. The first campaign was conducted in August 2015 with a base of operations in Ft. Lauderdale, Florida. Ten research flights were made into deep convective systems that included Mesoscale Convective Systems (MCS) near the Gulf of Mexico and Atlantic Ocean, and Tropical Storms Danny and Erika near the Caribbean Sea. The radar and in-situ measurements from these ten flights were analyzed and correlations defined. Key results included 1) derived relationships between radar reflectivity factor (RRF), Ice Water Content (IWC), and ice particle size distributions, 2) characterization of HIWC conditions at the -50°C and other flight levels, and 3) verification of pilot observations, such as low radar reflectivity factor and pitot and total air temperature (TAT) anomalies. This data set also enabled new pilot radar HIWC detection algorithms to be developed and tested. A second campaign was conducted in August 2018 to test proposed HIWC radar detection algorithms within a new set of storm systems. Seven research flights were conducted from bases of operations in Ft. Lauderdale, Florida; Palmdale, California; and Kona, Hawaii. Flights were made into convective systems over the Gulf of Mexico and into an eastern-Pacific tropical system that developed into Hurricane Lane. Using a new, NASA-developed radar processing technique called “Swerling”, regions of HIWC were identified, and estimates of IWC were produced, at distances up to 60 Nm ahead of the NASA DC-8. Subsequently, the DC-8 flew through these regions to acquire the in-situ measurements to verify the radar-based IWC estimates.
Ratvasky, Thomas, Harrah, Steven, Strapp, J. Walter, Lilie, Lyle, Proctor, Fred, Strickland, Justin, Hunt, Patricia, Bedka, Kristopher, Diskin, Glenn, Nowak, John B., Bui, T. P., Bansemer, Aaron, Dumont, Christopher
How Dual Polarization Technique May Improve Weather Radar on Commercial Aircraft2019-01-19826/10/2019
The airborne weather radar on a commercial aircraft is essential to ensure flight safety. It is able to detect severe weather, probable areas where presence of hail may be suspected, and thanks to its Doppler capability, the wind shears that may be dangerous when taking-off or landing. However, because it operates at X-band, the picture that it offers to the pilot may be seriously biased in situation of severe weather, in reason of the attenuation of the radar wave. The adoption of the dual pol technique in this weather radar would be most beneficial for the quality of the information delivered to the pilot for the following reasons: 1 Dual pol technique allows to operate a classification of the precipitation: distinguishing rain, melting layer, snow, hail, small ice particles. 2 Dual pol technique allows correcting the return signal for attenuation in rain. The paper aims reporting recent advances in the exploitation of dual pol radar data, based on the concept of normalisation of the particle size distribution (PSD) and on ZPHI® algorithm for precipitation retrieval. Their combination helps retrieving parameter N0* able to represent alone the variability of the PSD, for rain or ice particles whatever. The main interest of the combination between dual pol radar and ZPHI® software for inflight application is: To be able to measure ice concentration in altitude by implementing a new version of ZPHI® describing the along beam N0* evolution, in order to interpret the radar reflectivity in terms of ice particle concentration; To be able to calibrate the radar using self-consistency of polarimetric variables.
Testud, Jacques Victor, Moreau, Emmanuel, Le Bouar, Erwan
High Altitude Ice Crystal Detection with Aircraft X-band Weather Radar2019-01-20266/10/2019
During participation on EU FP7 HAIC project, Honeywell has developed methodology to detect High Altitude Ice Crystals with the Honeywell IntuVue® RDR-4000 X-band Weather Radar. The algorithm utilizes 3D weather buffer of RDR-4000 weather radar and is based on machine learning. The modified RDR-4000 Weather Radar was successfully flight tested during 2016 HAIC Validation Campaign; the technology was granted Technology Readiness Level 6 by HAIC consortium. After the end of HAIC project, the method was also evaluated with respect to newly set preliminary industry standard performance requirements1. This paper discuses technology design rationale, high level technology architecture, technology performance, and challenges associated with performance evaluation.
Lukas, Jan, Badin, Pavel
Monitoring Vital Signs Using RadarTBMG-345566/1/2019
A radar system can wirelessly monitor the vital signs of patients, eliminating the need to hook them up to any machines.
Speed and Maneuverability Benefits of Sikorsky's X2 Technology versus Air-Defense ArtilleryF-0075-2019-146565/13/2019
An aircraft's survivability in a hostile environment is a mixture of factors that stem from both susceptibility and vulnerability. Conducting analyses that incorporate these factors into a blended solution is vital. One such analysis was conducted using the government-provided Air-Defense Artillery (ADA) simulation tool Radar Directed Gun System (RADGUNS). RADGUNS provides a three-dimensional engagement space to conduct one versus one encounters against Radio Frequency (RF) guided threats. Complex user-generated flight paths can be simulated with varying relative starting locations of the aircraft relative to the threat being considered. The simulations conducted incorporated various aircraft parameters. Aircraft velocity, acceleration rates, deceleration rates, vulnerable area, and radar cross section (RCS) were the primary parameters whose effects were investigated. For each encounter, the Probability of Hit (P H) and Probability of Kill given a Hit (P K|H) were calculated, accounting for the susceptibility and vulnerability segments of the kill chain, respectively. A holistic metric of the kill chain, Probability of Kill (PK), and Engagement Time were the primary results of each engagement. Varying prominent aircraft input parameters can provide key insights in the prediction of an aircraft's survivability. This paper will focus on the benefits of speed and maneuverability, obtainable with Sikorsky's X2 Technology™ in the realm of survivability versus radar and human guided threats.
Foote, Bjorn, Robeson, Mark, Kaye, Jordan, Weintraub, Alexander, Kiser, Jay, Camp, Daniel
Multi-Domain Model for Rotorcraft Countermeasure DispensingF-0075-2019-146505/13/2019
A multi-domain Eulerian/Lagrangian approach for modeling transient behavior of countermeasures released from tactical rotorcraft is being developed, that tracks chaff/flares/pyrophorics properties from initial dispensing and bloom, through entrainment within the rotorcraft flowfield, to final settling to the ground. Development of the software leverages extensive prior simulation and experimental work conducted at CDI on droplet and particle modeling, fuel jettisoning, agricultural airborne spraying applications, icing accretion, brownout cloud simulation, and store separation clearance determination. The software is designed for supporting applications that include chaff dispenser mounting design, piloted simulation training and tactics development, and radar cross-section (RCS) determination and engagement simulations. The code couples in CDI's real-time free wake analysis to support the development of accurate time-varying signature calculations and expands the potential for analysis of tactics and doctrine for countermeasure dispensing in both steady and maneuvering rotorcraft flight conditions.
McKillip, Robert, Quackenbush, Todd
High-Performance, Current-Steering Digital-to-Analog ConverterTBMG-343955/1/2019
A current-steering digital-to-analog converter (DAC) was developed that achieves improved switching times (up to 75% faster) in high-speed (gigahertz), high-resolution (8-14 bits) applications resulting in improvement of spurious free dynamic range (SFDR).
Vision System for Detecting a Small Object at Far Range2019-01-08864/2/2019
As one of the advanced sensing technologies of Autonomous driving, we have started developing the new vision system. It focuses on detecting the small object at far ranges. It makes it possible to detour a vehicle along the traffic cones (small object). This system is based on the high-resolution mono-camera with narrow FOV and the algorithms for object-detection/ranging and lane-detection. A prototype is created and evaluated. It could detect the cones and estimate their ranges up to 150 [m]. The range accuracy is 5.3 [m]. Plural cones at different ranges can be measure at one time. The lane detection could reach 150 [m].
Miyahara, Shunji, Li, Huan, Xie, Kunpeng, Bai, Bai Jincheng
Application of Collision Probability Estimation to Calibration of Advanced Driver Assistance Systems2019-01-11334/2/2019
Advanced Driver Assistance Systems (ADAS) are designed and calibrated rigorously to provide them with the robustness against highly uncertain environments that they usually operate in. Typical calibration procedures for such systems rely extensively on track (controlled environment) testing, which is time-consuming, expensive, and sometimes cannot cover all the critical test scenarios that could be encountered by ADAS in the real world. Therefore, virtual (simulation-based) testing and validation has been gaining more prominence and emphasis for ensuring high coverage along with easier scalability and usage. This paper attempts to provide an alternative approach for calibrating ADAS in the controller validation phase by the aid of simulated test case scenarios. The study executes characterization of the uncertainty in the position and heading of the ego and the obstacle vehicles. This exercise captures the uncertainties in the states detection of vehicles in the environment and localization errors of the states of the ego vehicle. Following it, the approach estimates the probability of collision between the two vehicles for a given trajectory through a Monte Carlo approach. For illustration purposes, the method is then applied on tuning a Lane Change Assistance System for a four-wheel sedan equipped with Short-Range and Long-Range Radar Sensors.
Bithar, Vivek, Karumanchi, Aditya
System Enables Direct Data Transmission Between Underwater and Airborne DevicesTBMG-341654/1/2019
Today, underwater sensors cannot share data with those on land, as both use different wireless signals that only work in their respective mediums. Radio signals that travel through air die very rapidly in water. Acoustic signals, or sonar, sent by underwater devices mostly reflect off the surface without ever breaking through. This causes inefficiencies and other issues for a variety of applications such as ocean exploration and submarine-to-plane communication.
Aerospace & Defense Technology: April 201919AERP044/1/2019
An Integrated Framework for Complex Radar System Design Thermoplastic Composites to Play Enhanced Role in Next-Generation Aerospace Applications Using Ruggedized Test Equipment to Solve Jet Engine Problems How FMC Developments Support Legacy and Next-Gen Data Needs XPONENTIAL 2019 - An AUVSI Experience Understanding the 'Black Art' of RF and Microwave Switching A New Approach to Satellite Communications Modular Biosensor Patch Identifying new biomarkers to help monitor cognition and stress in the human body could enhance human performance. Characterization of Bore Temperatures and Stresses in Small Caliber Gun Barrels Data gathered from physical testing will be compared to analytical methods used to assess barrel wall temperature profiles and barrel wall stress and strain. Simulation of Active Imaging Systems Better data could lead to systems that improve tactical target acquisition, particularly under adverse environmental conditions. Deep Installation Method for Three-Component Seismic Sensors Standardized procedure for installing seismic sensors in a soil environment will allow non-experts to execute successfully with minimal training.
Multiplexing of Wireless Surface Acoustic Wave SensorsTBMG-341584/1/2019
The traditional approach for wireless sensors involves interrogators that communicate with each other (i.e., the two boxes “talk” to each other). In contrast, surface acoustic wave (SAW) sensors allow for a single box that can communicate with multiple sensors. One of the biggest advantages of SAW sensors over competing wireless sensors is that the SAW sensors do not require a power source.
Detecting Drones with Doppler-Based RadarTBMG-3302310/1/2018
As drones become more commonplace, the need to secure facilities from the high-definition cameras and potential dangerous payloads has caused a rapid growth of counter-drone technologies.
Hyperfine Interpolated Range Finding for CW Lidar, Radar, and Sonar Using Repeating Waveforms and Fourier Transform ReorderingTBMG-325188/1/2018
NASA's Langley Research Center has developed a novel fine interpolation technique that is useful in signal processing for applications in lidar, sonar, radar, and similar modalities. The interpolation technique uses repeating waveforms, Fourier transform reordering, and Richardson-Lucy deconvolution to obtain faster and more accurate results. The prime target application is range finding, but the technique is equally suitable for differential absorption studies, such as determining CO 2 concentrations in the atmosphere.
Co-Prime Frequency and Aperture Design for HF Surveillance, Wideband Radar Imaging, and Nonstationary Array ProcessingTBMG-290786/1/2018
A co-prime array uses two uniform linear subarrays to construct an effective difference coarray with certain desirable characteristics, such as a high number of degrees-of-freedom for DOA estimation. In this research, the co-prime array concept has been generalized with two operations.
Digital Radar Warning ReceiverTBMG-290816/1/2018
Northrop Grumman Corporation Falls Church, VA 703-280-2900
Tech Briefs: June 201818AERP066/1/2018
Beyond VMEbus - A New Concept Taming the Thermal Behavior of Solid-State Military Lasers Solving the Challenge of Thermal Design in Aerospace Electronics Improving Component Life in Abrasive, Corrosive Aerospace Environments New Pulse Analysis Techniques for Radar and EW Validation of Ubiquitous 2D Radar Converting Existing Copper Wire Firing System to a Fiber-Optically Controlled Firing System for Electromagnetic Pulsed Power Experiments Technological improvements make pulsed-power experiments with gunpowder- or air-driven guns safer. Low-Cost Ground Sensor Network for Intrusion Detection COTS-based system could provide increased level of security with less manpower. In-Network Processing on Low-Cost IoT Nodes for Maritime Surveillance Commercially available system of distributed wireless sensors could increase the Navy's intelligence collection footprint. Co-Prime Frequency and Aperture Design for HF Surveillance, Wideband Radar Imaging, and Nonstationary Array Processing Developing novel co-prime sampling and array design strategies to achieve high-resolution estimation of spectral power distributions and signal direction-of-arrivals (DOAs).
Fail-Operational Safety Architecture for ADAS Systems Considering Domain ECUs2018-01-10694/3/2018
In recent years the automotive companies are developing their self-driving technology very rapidly. Most of them want to launch their self-driving vehicles with SAE level 4 at the beginning of 2020. The main goal of the development of self-driving cars is to reduce accidents caused by driver errors. But there are some technological challenges to solve such as increasing of the safety and availability in order to get the acceptance from the customers. The purpose of this research is to investigate the possible fail-operational safety architectures for both conventional systems as powertrain and the entire ADAS processing chain. The solutions show how the redundant system architecture and safety architecture can be created efficiently and diverse redundancy for ADAS systems considering the processing chain from sensors such as camera, radar, lidar, etc. to perception and decision algorithms in order to fulfill the ASIL D safety requirements and to increase the system availability with fail-operational for self-driving vehicles with SAE Level 3 and fully self-driving vehicles with SAE level 4 and level 5.
Sari, Bülent, Reuss, Hans-Christian
The Effect of Target Features on Toyota’s Autonomous Emergency Braking System2018-01-05334/3/2018
The Pre-Collision System (PCS) in Toyota’s Safety Sense package includes an autonomous emergency braking feature that can stop or slow a vehicle independent of driver input if there is an impending collision. The goals of this study were to determine how hazard characteristics, specifically radar reflector size and degree of target edge contrast, affect the response of the PCS, as well as to scrutinize tests wherein the PCS failed to stop the vehicle before impact. We conducted 80 tests with a 2017 Toyota Corolla driven towards a car-like target in a straight line and under constant accelerator pedal position, reaching about 30 km/h at the PCS alarm. Vehicle speed and distance to target at the alarm flag (ALM) and at times corresponding to three other system flags (PBA, FPB, and PB) were read from the Vehicle Control History records. Time to impact (TTI) at each flag was calculated and the distance between the stopped vehicle and the target was measured for each test. The PCS detected the hazard in all tests. We found that when there was little or no driver input, the PCS stopped the vehicle autonomously in all but one test. Target radar size and contrast did not affect the speeds, distances or TTIs in these tests. In some tests, the PCS and ABS interacted in a way that increased the stopping distance. In a small number of tests, the PCS disengaged partway through its algorithm and returned control to the driver for reasons that we were unable to discern. This study provides some initial insights into the dynamic response of the Toyota PCS and identifies some factors that affect its performance.
Yang, Mike, Xing, Peter, Flynn, Thomas, Tsuge, Brandon, Lawrence, Jonathan, Siegmund, Gunter P.
The Accuracy of Toyota Vehicle Control History Data during Autonomous Emergency Braking2018-01-14414/3/2018
Newer Toyota vehicles store information about more than 50 parameters for 5 s before and after non-collision events in the Vehicle Control History (VCH) records. The goals of this study were to assess the accuracy of VCH data acquired during Autonomous Emergency Braking (AEB) events and to investigate the effects of speed, acceleration, and system settings on AEB performance. A 2017 Toyota Corolla with Safety Sense P Pre-Collision System (PCS) was driven in a straight line towards a car-like target at different combinations of four speeds (20, 25, 30, and 40 km/h; or 12, 15, 19, and 25 mph) and three accelerator pedal positions (constant 30%, 40%, and 50% accelerator opening ratios) until the AEB system activated. The vehicle speed, vehicle acceleration, radar target closing speed, and radar target distance recorded in the VCH were compared to a reference 5th wheel. We found that errors in the VCH distance, speed, and acceleration data varied with the test conditions. Regression equations were derived to better predict distance, speed, and acceleration from the VCH data. A driver-adjustable PCS warning setting only altered the timing of the warning and not the underlying AEB response. The vehicle struck the target most often at 20 km/h (12 mph) when accelerating towards the target, but did not strike the target when approaching it at a constant speed of 20 km/h. This study serves as an initial investigation into the accuracy of VCH data and the performance of the Toyota PCS under various conditions and settings.
Xing, Peter, Yang, Mike, Tsuge, Brandon, Flynn, Thomas, Lawrence, Jonathan, Siegmund, Gunter P.
Study on Target Tracking Based on Vision and Radar Sensor Fusion2018-01-06134/3/2018
Faced with intricate traffic conditions, the single sensor has been unable to meet the safety requirements of Advanced Driver Assistance Systems (ADAS) and autonomous driving. In the field of multi-target tracking, the number of targets detected by vision sensor is sometimes less than the current tracks while the number of targets detected by millimeter wave radar is more than the current tracks. Hence, a multi-sensor information fusion algorithm is presented by utilizing advantage of both vision sensor and millimeter wave radar. The multi-sensor fusion algorithm is based on centralized fusion strategy that the fusion center takes a unified track management. At First, vision sensor and radar are used to detect the target and to measure the range and the azimuth angle of the target. Then, the detections data from vision sensor and radar is transferred to fusion center to join the multi-target tracking with the prediction of current tracks. Vision sensor uses Global Nearest Neighbor (GNN), and radar uses Probabilistic Data Association (PDA) for data association. For target detection, the vision sensor has high accuracy at azimuth angle and low accuracy at range, while radar has medium accuracy at azimuth angle and very high accuracy at range. The detection properties of two sensors should be considered when designing the association gate. Simulation based on real test data which was taken by a monocular camera and a 77GHz millimeter wave radar is performed in MATLAB. Simulation result indicates that the design of association gate has a great impact on fusion performance.
Wu, Xian, Ren, Jing, Wu, Yujun, Shao, Jianwang
Radar Sensor SystemsTBMG-287864/1/2018
Kelvin Hughes London, UK +44 19 9280 5200
New Osram IREDs enhance vehicle vision without harming human eyes18AUTP08_081/1/2018
As a compliment to cameras, LiDAR and radar, a new family of Infrared LEDs (IREDs) can expand the vision of SAE Level 4 and 5 autonomous vehicles without harming human eyes, claims maker Osram Opto Semiconductors. Infrared night vision cameras, LiDAR, radar, and vehicle headlights will provide autonomous vehicles with an ability to see the surroundings at night, but the technologies have limitations.
Buchholz, Kami
Device for and Method of Computer Intrusion Anticipation, Detection, and RemediationTBMG-2780111/1/2017
Initially, relatively powerful computers were constructed as unique mainframes operated by larger corporations on isolated networks. Then, computers with modest amounts of computing power were made available to individuals as standalone personal computers. The computing power of personal computers and the applications for which they could be used were increased by networking them with other computers throughout the world using ancillary devices (e.g., servers, routers, links, switches, hubs, etc.). An arrangement into which computer and ancillary devices are configured is called a topology. There are many different types of topologies (e.g., bus, ring, star, tree, mesh, etc.).
A Modified Chirp Sequence Design for Monopulse Automotive Radar2017-01-19749/23/2017
In the last years, in order to fit the requirements of automotive radar application under the multi-target conditions, several proposals about Continuous Waveform (CW)have been developed. The transmit signal with Multiple Frequency Shift Keying (MFSK) technology was developed to analyze the target information in range domain and Doppler frequency domain simultaneously, but the MFSK waveform has lower estimation accuracy in phase measuring. A higher accuracy signal type is the chirp sequence waveform of monopulse radar, which is based on two-dimension independent frequency measuring. It can also get the range and velocity information, but might lead to ambiguities in Doppler domain. To avoid the Doppler ambiguity, a method is proposed in this paper, which uses the modified chirp sequence waveform. The carrier frequencies of the modified chirp sequence are different, which causes the Doppler frequency offset. Doppler ambiguities have no influence on the Doppler frequency offset and the speed of targets can be derived from carrier frequency offset and Doppler frequency offset. Thus, the modified chirp sequence avoids the ambiguities in velocity and guarantees the measurement accuracy even in multi-target conditions. It has advantages in the automotive radar applications.
Chen, Tao, Bai, Jie, Wang, Fang, Huang, Libo
2-D CFAR Procedure of Multiple Target Detection for Automotive Radar07-11-01-00079/23/2017
In Advanced Driver Assistant System (ADAS), the automotive radar is used to detect targets or obstacles around the vehicle. The procedure of Constant False Alarm Rate (CFAR) plays an important role in adaptive targets detection in noise or clutter environment. But in practical applications, the noise or clutter power is absolutely unknown and varies over the change of range, time and angle. The well-known cell averaging (CA) CFAR detector has a good detection performance in homogeneous environment but suffers from masking effect in multi-target environment. The ordered statistic (OS) CFAR is more robust in multi-target environment but needs a high computation power. Therefore, in this paper, a new two-dimension CFAR procedure based on a combination of Generalized Order Statistic (GOS) and CA CFAR named GOS-CA CFAR is proposed. Besides, the Linear Frequency Modulation Continuous Wave (LFMCW) radar simulation system is built to produce a series of rapid chirp signals. Then the echo signals are converted into a two-dimensional Range-Doppler matrix (RDM), which contains information about the targets as well as background clutter and noise, through twice Fast Fourier Transform (FFT).The simulation experimental results show that compared to the two-dimensional OS-CA CFAR, the new 2-D GOS-CA CFAR can enhance the detection performance and robustness in the actual multi-target environment with lower computational complexity.
Li, Sen, Bi, Xin, Tan, Bin, Huang, Libo
Cassini Stays in Touch with NASA's Radio Science Subsystem17AERP06_066/1/2017
After almost 20 years in space, NASA's Cassini spacecraft begins the final chapter of its remarkable story of exploration. From now until September, Cassini will undertake a set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn's moon Titan, Cassini will leap over the planet's icy rings and begin a series of 22 weekly dives between the planet and the rings. Launched in 1997, Cassini arrived at Saturn in 2004. Following its last close flyby of Titan in April, Cassini began what mission planners are calling its Grand Finale. The spacecraft is on a trajectory that will eventually plunge into Saturn's atmosphere - and end Cassini's mission - on September 15.
Cassini Stays in Touch with NASA's Radio Science SubsystemTBMG-269976/1/2017
After almost 20 years in space, NASA's Cassini spacecraft begins the final chapter of its remarkable story of exploration. From now until September, Cassini will undertake a set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn's moon Titan, Cassini will leap over the planet's icy rings and begin a series of 22 weekly dives between the planet and the rings.
Developing a Satellite-Based Autonomous Vehicle Control SystemTBMG-270476/1/2017
The rapid rise of global interest in the field of autonomous driving is ushering in a new era of automobiles. With many vehicles already offering autonomous preventative safety systems, the addition of improved road infrastructure could increase the reliability and maturity of autonomous driving functions, ultimately increasing the driver's sense of safety.
Digital Beamforming InterferometryTBMG-270246/1/2017
NASA Goddard Space Flight Center has developed a new radar approach that uses a single phased array antenna and a single-pass configuration to generate interferograms, known as Digital Beamforming Interferometry. A digital beamforming radar system allows the implementation of nonconventional radar techniques, known as Digital Beamforming Synthetic Aperture Radar Multimode Operation (DBSAR).
3D-Sonification for Obstacle Avoidance in Brownout ConditionsF-0073-2017-120465/9/2017
ABSTRACT Helicopter brownout is a phenomenon that occurs when making landing approaches in dusty environments, whereby sand or dust particles become swept up in the rotor outwash. Brownout is characterized by partial or total obscuration of the terrain, which degrades visual cues necessary for hovering and safe landing. Furthermore, the motion of the dust cloud produced during brownout can lead to the pilot experiencing motion cue anomalies such as vection illusions. In this context, the stability and guidance control functions can be intermittently or continuously degraded, potentially leading to undetected surface hazards and obstacles as well as unnoticed drift. Safe and controlled landing in brownout can be achieved using an integrated presentation of LADAR and RADAR imagery and aircraft state symbology. However, though detected by the LADAR and displayed on the sensor image, small obstacles can be difficult to discern from the background so that changes in obstacle elevation may go unnoticed. Moreover, pilot workload associated with tracking the displayed symbology is often so high that the pilot cannot give sufficient attention to the LADAR/RADAR image. This paper documents a simulation evaluating the use of 3D auditory cueing for obstacle avoidance in brownout as a replacement for or compliment to LADAR/RADAR imagery.
Godfroy-Cooper, M., Wenzel, E., Szoboszlay, Z., Miller, J.
An Interview with General Richard A. Cody: The Soldiers' General and His Enduring Impact on Army AviationF-0073-2017-120925/9/2017
ABSTRACT The Army Aviation Hall of Fame states that "No individual has had a greater impact on the Army and the Aviation Branch" than General Richard Cody. After receiving his commission in 1972 at West Point, Cody served with distinction for 36 years until retiring as the Army's 31st Vice Chief of Staff in 2008. While still a Lieutenant Colonel, in 1991 he led his Apache battalion into Iraq to fire the first shots of Operation DESERT STORM, eliminating critical enemy radar sites before the air war campaign even began. In the years following September 11, 2001, as Deputy Chief of Staff for Operations (G-3/5/7) and then as Vice Chief of Staff, his efforts led to the most sweeping transformation the Army and the Aviation Branch had ever seen. An ace special operations pilot and brilliant military mastermind, General Cody may best be remembered, however, as the well-loved "Soldiers' General."
Fardink, Paul
Submarine Radar TechnologyTBMG-267544/1/2017
Kelvin Hughes Enfield, UK +44 19 9280 5200
3D Automotive Millimeter-Wave Radar with Two-Dimensional Electronic Scanning2017-01-00473/28/2017
The radar-based advanced driver assistance systems (ADAS) like autonomous emergency braking (AEB) and forward collision warning (FCW) can reduce accidents, so as to make vehicles, drivers and pedestrians safer. For active safety, automotive millimeter-wave radar is an indispensable role in the automotive environmental sensing system since it can work effectively regardless of the bad weather while the camera fails. One crucial task of the automotive radar is to detect and distinguish some objects close to each other precisely with the increasingly complex of the road condition. Nowadays almost all the automotive radar products work in bidimensional area where just the range and azimuth can be measured. However, sometimes in their field of view it is not easy for them to differentiate some objects, like the car, the manhole covers and the guide board, when they align with each other in vertical direction. In other words, those objects are counted as one erroneously because of absence of height information. In practice, road conditions are complicated and unpredictable, these unexpected mistakes will make the ADAS poor performance or even collapse, e.g. unwanted abrupt brake due to the detected manhole cover or guide board. Plus, the subsequent target tracking would be made an arduous task and with untrusted output. This paper proposes an automotive radar architecture with two-dimensional electronic scanning, which can obtain 3D information--range, azimuth and height. Four antennas including one transmitting antenna and three receiving antennas are used in this scheme. In addition to two conventional receiving antennas placed in horizon, another receiving antenna is arranged in vertical aligning with one of the other two to obtain the height information so that the corresponding detected targets can be distinguished clearly. Furthermore, when more antennas utilized this architecture can be extended easily for higher autonomous driving requirements. A range of simulation indicates that this radar architecture can measure object height and the effectiveness of proposed architecture is further verified in actual experiments on the corresponding radar prototype. It is low-cost and with small size, and the car grade design and development make the further application in ADAS possible.
Bai, Jie, CHEN, Sihan, Cui, Hua, Bi, Xin, Huang, Libo
Real-Time Estimation of Radar Cross Section for ADAS Simulation2017-01-00283/28/2017
This paper proposes a Real-Time Estimation of Radar Cross Section for ADAS Simulation, aimed to enable math-based virtual development and test of ADAS. The electromagnetic scattering mechanism is firstly analyzed with targets to be typical objects in traffic. Then a geometric model is developed, in which the object surfaces are divided into multiple scattering zones corresponding to different scattering mechanism. According to different surface curvature radius and scattering mechanism, the scattering zones are approximately equivalent to plane, cylinder, sphere and so on. Using the ARD model based on an improved physical optics and diffraction theory, RCS value of a zone is estimated. Then the RCS of the object surface is obtained by vector superposition of all zones. Some typical simulation comparisons are carried out, which proves the practicability of our method.
Li, Xin, Deng, Weiwen
Items per page:
1 – 50 of 281