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SLD and Ice Crystal Discrimination with the Optical Ice Detector

Collins Aerospace-Kaare J. Anderson, Mark D. Ray
  • Technical Paper
  • 2019-01-1934
To be published on 2019-06-10 by SAE International in United States
Recent years have seen increased awareness within the aerospace community of icing hazards posed by conditions beyond those described by 14 CFR Part 25, Appendix C. Engine and airframe manufacturers are now required to certify their products for operation in the presence of supercooled large droplets (SLD) and high ice water content (HIWC) conditions, or alternatively, to implement a detect-and-exit strategy. The latter option implies a need for the capability of detecting Appendix C, SLD, and HIWC conditions, and to discriminate between them. The Optical Ice Detector (OID) technology under development at Collins Aerospace provides the ability to detect and differentiate Appendix C, Appendix O, and Appendix D conditions with a compact cloud lidar system. The OID’s ability to determine bulk cloud phase and water content has been previously demonstrated. Recent development efforts have focused on expanding the OID’s capabilities to also enable differentiation between small droplet clouds and bimodal clouds such as those described by Appendix O. This is enabled through statistical analysis of ensembles of individual lidar cloud reflection signals. Combined with the…
 

Uncertainty of the Ice Particles Median Mass Diameters Retrieved from the HAIC-HIWC Dataset: a Study of the Influence of the Mass Retrieval Method

Delphine Leroy, J. Walter Strapp
Airbus France-Alice Grandin
  • Technical Paper
  • 2019-01-1983
To be published on 2019-06-10 by SAE International in United States
In response to the ice crystal icing hazard identified twenty years ago, aviation industry, regulation authorities, and research centers joined forces into the HAIC-HIWC international collaboration launched in 2012. Two flight campaigns were conducted in the high ice water content areas of tropical mesoscale convective systems in order to characterize this environment conducive to ice crystal icing. Statistics on cloud microphysical properties, such as Ice Water Content (IWC) or Mass Median Diameter (MMD), derived from the dataset of in situ measurements are now being used to support icing certification rulemaking and anti-icing systems design (engine and air data probe) activities. This technical paper focuses on methodological aspects of the derivation of MMD. There is currently no direct method to measure the MMD of an ice particle size distribution (PSD). Instead, MMD were estimated from PSD and IWC using a multistep process. Critical in this process is the mass retrieval method necessary to estimate mass distributions, from which MMDs are calculated. This step implies assumptions that make the MMD values prone to uncertainty due to methodological…
 

An Explorative Study to Use Super-Hydrophilic/Super-Hydrophobic Hybrid Surfaces for Aircraft Icing Mitigation

Iowa State University-Haiyang Hu, Hui Hu, Yang Liu
  • Technical Paper
  • 2019-01-1995
To be published on 2019-06-10 by SAE International in United States
Aircraft icing is widely recognized as one of the most severe hazards to aircraft operating in cold weather. In the present study, a novel hybrid anti-/de-icing strategy, i.e., by combining an electric heating film coated with super-hydrophilic coatings near the airfoil leading edge and a super-hydrophobic coating to cover the rest of the airfoil surface, was explored for aircraft icing mitigation, in comparison with the method to cover bother electric heating film and the airfoil surface only with a super-hydrophobic surface coating. While a comprehensive experimental study was conducted to examine the characteristics of dynamic droplet impingement onto solid surfaces with different wettability used for the hybrid approach, a NACA0012 airfoil/wing model implemented with two different hybrid methods was installed in the Icing Research Tunnel at Iowa State University (i.e., ISU-IRT) for the anti-/de-icing experiments. It was found that, the supercooled water droplets continued spreading without receding and bouncing after impacting onto the super-hydrophilic surface, the wetting area for the super-hydrophilic surface was found to be about five times larger than those over the super-hydrophobic…
 
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Development of Evaluation Methods for Steering Loss of Assist

General Motors-Ibrahim A. Badiru, Valarie Boatman, Steve Gornick, Brian Latouf, Peter Shear, Richard Krentz
Published 2019-04-02 by SAE International in United States
Loss of power steering assist (LoA) is viewed as a potential hazard in certain vehicle operational scenarios. Despite the importance of this steering failure mode, few published test protocols for the objective or subjective evaluation of vehicle performance in a loss of assist situation exist.The first part of this paper examines five of the key steering failure modes that can result in LoA and discusses why LoA persists as a key industry challenge. The second part analyzes the situational dynamics affecting vehicle controllability during a LoA event and proposes a subjective evaluation driving course that facilitates evaluations in various LoA scenarios. A corresponding objective test procedure and metric is also proposed. These evaluation methods support consistent performance evaluation of physical vehicles while also enabling the prediction of vehicle characteristics early in the vehicle development process (VDP). The final section of this paper gives an overview of a steering system design method aimed at first classifying the level of risk associated with any LoA induced hazard (Automotive Safety Integrity Level - ASIL) and then taking appropriate…
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Effectiveness of Warning Signals in Semi-Autonomous Vehicles

Ohio State University-Simon Trask, Madeline Stewart, Thomas Kerwin, Shawn Midlam-Mohler
Published 2019-04-02 by SAE International in United States
The rise of automation in the automotive industry has ensured significant progress in vehicle safety and infrastructure. During the transition to full autonomy, the driver is often the redundancy and safety feature in the event of a hazard or automation error. Understanding driver behavior in the transition from non-driver to driver is important for safety. Proper handling of transitions will be more critical as these events become less common and users trust automated driving systems. This research investigates the case of SAE level-3 automated driving systems, where the driver need not constantly pay attention but is responsible for reaction during hazards. Findings include quantitative and qualitative assessment of various warning modes for a distracted driver responding to an automated driving failure situation. Driver response time and behavior for these events are compared to instances with minimal warning systems. The results offer insight into human-vehicle interfaces during the transition towards full autonomy.
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Hazard Cuing Systems for Teen Drivers: A Test-Track Evaluation on Mcity

DENSO International America Inc.-Yu Zhang, Te-Ping Kang
University of Michigan-Michael Flannagan, Shan Bao, Anuj Pradhan, John Sullivan
  • Technical Paper
  • 2019-01-0399
Published 2019-04-02 by SAE International in United States
There is a strong evidence that the overrepresentation of teen drivers in motor vehicle crashes is mainly due to their poor hazard perception skills, i.e., they are unskilled at appropriately detecting and responding to roadway hazards. This study evaluates two cuing systems designed to help teens better understand their driving environment. Both systems use directional color-coding to represent different levels of proximity between one’s vehicle and outside agents. The first system provides an overview of the location of adjacent objects in a head-up display in front of the driver and relies on drivers’ focal vision (focal cuing system). The second system presents similar information, but in the drivers’ peripheral vision, by using ambient lights (peripheral cuing system). Both systems were retrofitted into a test vehicle (2014 Toyota Camry). A within-subject experiment was conducted at the University of Michigan Mcity test-track facility. The study collected data from seventeen teen participants. Each participant experienced three cuing conditions (focal cuing, peripheral cuing and dual system cuing conditions) as well as three no cuing system conditions (two practice, a…
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Tracking of Extended Objects with Multiple Three-Dimensional High-Resolution Automotive Millimeter Wave Radar

Automotive Sensors Group-Libo Huang
Tongji University-Jie Bai, Bin Tan, Xin Bi
Published 2019-04-02 by SAE International in United States
Estimating the motion state of peripheral targets is a very important part in the environment perception of intelligent vehicles. The accurate estimation of the motion state of the peripheral targets can provide more information for the intelligent vehicle planning module which means the intelligent vehicle is able to anticipate hazards ahead of time. To get the motion state of the target accurately, the target’s range, velocity, orientation angle and yaw rate need to be estimated. Three-dimensional high-resolution automotive millimeter wave radar can measure radial range, radial velocity, azimuth angle and elevation angle about multiple reflections of an extended target. Thus, the three-dimensional range information and three-dimensional velocity information can be obtained. With multiple three-dimensional high-resolution automotive millimeter-wave radar, it is possible to measure information in various directions of a target. For tracking of extended objects with multiple three-dimensional high-resolution automotive millimeter wave radar, firstly, the information of one target in different radar is obtained by the clustering algorithm, and then it is fused by an unscented Kalman filter, and the tracking algorithm needs to consider…
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Exhaust Plume Analyzer

  • Magazine Article
  • TBMG-33600
Published 2019-01-01 by Tech Briefs Media Group in United States

Exhaust plumes emanating from smoke stacks at power plants or other industrial facilities can have adverse impacts on local aviation during periods of calm winds. Adverse impacts can be exacerbated if the temperature is low or the atmosphere is unstable. While low oxygen concentrations and elevated temperatures inside the plume can be detrimental to slow-flying or hovering helicopters, the turbulence generated from the upward motion of the plume is the main potential hazard to light, fixed-wing aircraft at low altitudes.

 

Theory of Collision Avoidance Capability in Automated Driving Technologies

Toyota Motor Corporation, Japan-Toshiki Kindo
Toyota Research Institute-North America, USA-Bunyo Okumura
  • Journal Article
  • 12-01-02-0004
Published 2018-10-29 by SAE International in United States
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 always efficient. The theory suggests that applicative driving plan of automated vehicle is as follows: 1) the automated vehicle takes the…
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Direct-Current Detector for Emergency Responder Safety

  • Magazine Article
  • TBMG-32863
Published 2018-09-01 by Tech Briefs Media Group in United States

The Department of Energy's Oak Ridge National Laboratory has developed a direct-current detector technology to help emergency responders safely detect high voltages, which they have licensed to North Carolina-based Hotstick USA.