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Real-time Motion Classification of LiDAR Point Detection for Automated Vehicles

Hanyang University-Chansoo Kim, Sungjin Cho, Myoungho Sunwoo
Konkuk University-Kichun Jo
  • Technical Paper
  • 2020-01-0703
To be published on 2020-04-14 by SAE International in United States
A Light Detection And Ranging (LiDAR) is now becoming an essential sensor for an autonomous vehicle. The LiDAR provides the surrounding environment information of the vehicle in the form of a point cloud. A decision-making system of the autonomous car is able to determine a safe and comfort maneuver by utilizing the detected LiDAR point cloud. If the movement class (dynamic or static) of detected points can be provided by LiDAR, the decision-making system is able to plan the appropriate motion of the autonomous vehicle according to the movement of the object. This paper proposes a real-time process to segment the motion states of LiDAR points. The basic principle of the classification algorithm is to classify the point-wise movement of a target point cloud through the other point clouds and sensor poses. First, a fixed-size buffer store the LiDAR point clouds and sensor poses for a constant time window. Second, motion beliefs of the target point cloud against other point clouds and sensor pose in the buffer are estimated, respectively. Each motion belief of the…
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Using Reinforcement Learning and Simulation to Develop Autonomous Vehicle Control Strategies

Amazon Web Services-Sahika Genc, Premkumar Rangarajan
PolySync Technologies-Anthony Navarro
  • Technical Paper
  • 2020-01-0737
To be published on 2020-04-14 by SAE International in United States
While machine learning in autonomous vehicles development has increased significantly in the past few years, the use of reinforcement learning (RL) methods has only recently been applied. Convolutional neural networks (CNNs) became common for their powerful object detection and identification and even provided end-to-end control of an autonomous vehicle. However, one of the requirements of a CNN is a large amount of labeled data to inform the neural network. While data is becoming more accessible, these networks are still sensitive to the format and collection environment which makes the use of others’ data more difficult. In contrast, RL develops solutions in a simulation environment by trial and error without labeled data. Our research expands upon previous research in RL and proximal policy optimization (PPO) and the application of these algorithms to 1/18th scale cars by expanding the application of this control strategy to a full-sized passenger vehicle. By using this method of unsupervised learning, our research demonstrates the ability to learn new control strategies while in a simulation environment without the need for large amounts…
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A Method for Mapping a Light Source Utilizing HDR Imagery

JS Forensic Consulting, LLC-Jeffrey Suway
Momenta, LLC-Anthony Cornetto
  • Technical Paper
  • 2020-01-0566
To be published on 2020-04-14 by SAE International in United States
Mapping a light source, any light source, is of broad interest to accident reconstructionists, human factors professionals and lighting experts. Such mappings are useful for a variety of purposes, including determining the effectiveness and appropriateness of lighting installations, and performing visibility analyses for accident case studies. Currently, mapping a light source can be achieved with several different methods. One such method is to use an illuminance meter and physically measure each point of interest on the roadway. Another method utilizes a goniometer to measure the luminous intensity distribution, this is a near-field measurement. Both methods require significant time and the goniometric method requires extensive equipment in a lab. A third method measures illumination distribution in the far-field using a colorimeter or photometer. These systems utilize a CCD sensor to measure the illuminance distribution and then software can convert that illuminance distribution to an IES file for use in a Physically-Based Rendering (PBR) engine. Again, this photometer method requires extensive equipment and the measurements must be taken in a laboratory setting. The method presented in this…
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Numerical Investigation of Friction Material Contact Mechanics in Automotive Clutches

FCC Co., Ltd.-Masatoshi Miyagawa, Takahiro Tsuchiya, Shinji Nakamura, Matthew Wendel
Ford Motor Company-Hiral Haria, David Popejoy, Rachel Divinagracia, Yuji Fujii
  • Technical Paper
  • 2020-01-1417
To be published on 2020-04-14 by SAE International in United States
A wet clutch model is required in automotive propulsion system simulations for enabling robust design and control development. It commonly assumes Coulomb friction for simplicity, even though it does not represent the physics of hydrodynamic torque transfer. In practice, the Coulomb friction coefficient is treated as a tuning parameter in simulations to match vehicle data for targeted conditions. The simulations tend to deviate from actual behaviors for different drive conditions unless the friction coefficient is adjusted repeatedly. Alternatively, a complex hydrodynamic model, coupled with a surface contact model, is utilized to enhance the fidelity of system simulations for broader conditions. The theory of elastic asperity deformation is conventionally employed to model clutch surface contact. However, recent examination of friction material shows that the elastic modulus of surface fibers significantly exceeds the contact load, implying no deformation of fibers. This article investigates the friction material contact mechanics through numerical simulations. A surface model is constructed based on microscopic examination of material topography and properties. An FEM simulation is conducted to examine the interactions between surface fibers…
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Automotive Dimensional Quality Control with Geometry Tree Process

FCA US LLC-James Cole, Yuqin Wang, Robert Bertucci
  • Technical Paper
  • 2020-01-0480
To be published on 2020-04-14 by SAE International in United States
Geometry Tree is a term describing the product assembly structure and the manufacturing process for the product. The concept refers to the assembly structure of the final vehicle (the Part Tree) and the assembly process and tools for the final product (the Process Tree). In the past few years, the Geometry Tree-based quality process was piloted in the FCA NAFTA region and has since evolved into a standardized quality control process. In the Part Tree process, the coordinated measurements and naming convention are enforced throughout the different levels of product sub-assemblies and measurement processes. The Process Tree, on the other hand, includes both prominently identified assembly tools and the mapping of key product characteristics to key assembly tools. The benefits of directly tying critical customer characteristics to actual machine components that have a high propensity to influence them is both preventive and reactive. This article describes the integrated Geometry Tree quality process and how it has been implemented at the FCA vehicle assembly plants and in the dimensional data management system.
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Assessing Fit and Finish Design Sensitivity By Mapping Measurements to VNM Utility

FCA US LLC-Christopher Slon, Xiaona LI, Vita Valetchikov
Oakland University-Vijitashwa Pandey
  • Technical Paper
  • 2020-01-0600
To be published on 2020-04-14 by SAE International in United States
In the automotive industry “fit and finish” is the term applied to the perceived quality of the alignment of one part to another. Fit and finish gives the buyer a sense of the overall quality of the vehicle purely from an aesthetic perspective. Fit and finish is usually evaluated by the manufacturer through dimensional measurements of the “gap” and “flush” conditions between panels. Since variation in the measurements increases the probability that a vehicle will result in poor fit and finish, relatively arbitrary limits are put on these measurements to define whether a gap or flush condition is acceptable or not. It is suspected that the relationship between the appropriate measurement limits and the customer’s perception of quality is highly influenced by the design of the interface between panels. This paper proposes a method to evaluate the sensitivity of the perceived quality of the designed interface to variation in the measurements of gap and flush. The novelty is in the application of the concept of von Neumann-Morgestern utility to fit and finish. The significance is…
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Lidar Inertial Odometry and Mapping for Autonomous Vehicle in GPS-denied Parking Lot

Jilin University-Xuesong Chen, Sumin Zhang, Jian Wu, Rui He, Shiping Song, Bing Zhu, Jian Zhao
  • Technical Paper
  • 2020-01-0103
To be published on 2020-04-14 by SAE International in United States
High-precision and real-time ego-motion estimation is vital for autonomous vehicle. There is a lot GPS-denied maneuver such as underground parking lot in urban areas. Therefore, the localization system relying solely on GPS cannot meets the requirements. Recently, lidar odometry and visual odometry have been introduced into localization systems to overcome the problem of missing GPS signals. Compared with visual odometry, lidar odometry is not susceptible to light, which is widely applied in weak-light environments. Besides, the autonomous parking is highly dependent on the geometric information around the vehicle, which makes building map of surroundings essential for autonomous vehicle. We propose a lidar inertial odometry and mapping. By sensor fusion, we compensate for the drawback of applying a single sensor, allowing the system to provide a more accurate estimate. Compared to other odometry using IMU and lidar, we apply a tight coupled of lidar and IMU method to achieve lower drift, which can effectively overcome the degradation problem based on pure lidar method, ensuring precise pose estimation in fast motion. In addition, we propose a map…
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The Investigation of the Structure and Origins of Gasoline Direct Injection (GDI) Deposits.

Innospec-J Barker J Reid, S Mulqueen
University of Sheffield-J Castle
  • Technical Paper
  • 2019-01-2356
Published 2019-12-19 by SAE International in United States
The legislative pressures on environmental targets combined with fuel economy requirements have led to the GDI engine enjoying a renaissance. This is because the technology is considered to be the leader in meeting those requirements. However it is also recognized that the engine suffers from injector deposits (ID) and that understanding the formation of and characterization of such deposits is required. This study will deal with the characterization and morphology of injector deposits as well as the fuel constituents leading to such deposits. A number of analytical techniques were used to undertake this such as Scanning Electron microscopy and X-ray Fluorescence (SEM/EDS) mapping with Fourier Transform Infra-red mapping, in conjunction with mass spectrometry studies. Further, work will be described regarding new deposit control additives (DCAs) for GDI which are more effective than traditional DCAs.
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Mapping Canada - Centimeter by Centimeter

Autonomous Vehicle Engineering: December 2019

Sebastian Blanco
  • Magazine Article
  • 19AVEP11_05
Published 2019-11-01 by SAE International in United States

A Montreal-based company leverages artificial intelligence to take on the task of developing high-definition maps of Canada.

Fully-automated vehicles will only be as smart as the datasets they use to determine their driving pathways. Jakarto Cartographie 3D, a young company based in Montreal, Canada, is working on artificial-intelligence (AI)-powered, high-definition (HD) maps that it claims offer 2-3 cm (.787- to 1.2-inch) absolute precision and relative precision measured in millimeters. In other words, better maps that will allow for better automated vehicles (AVs).

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Nondestructive Measurement of Residual Strain in Connecting Rods Using Neutrons

SAE International Journal of Materials and Manufacturing

Honda R&D Co., Ltd., Japan-Tomohiro Ikeda, Ryuta Motani, Hideki Matsuda, Tatsuya Okayama
Oak Ridge National Laboratory, USA-Bunn R. Jeffery, Christopher M. Fancher
  • Journal Article
  • 05-12-03-0018
Published 2019-10-15 by SAE International in United States
Increasing the strength of materials is effective in reducing weight and boosting structural part performance, but there are cases where the residual strain generated during the process of manufacturing of high-strength materials results in a decline of durability. It is therefore important to understand how the residual strain in a manufactured component changes due to processing conditions. In the case of a connecting rod, because the strain load on the connecting rod rib sections is high, it is necessary to clearly understand the distribution of strain in the ribs. However, because residual strain is generally measured by using X-ray diffractometers or strain gauges, measurements are limited to the surface layer of the parts. Neutron beams, however, have a higher penetration depth than X-rays, allowing for strain measurement in the bulk material. The research discussed within this article consists of nondestructive residual strain measurements in the interior of connecting rods using the Second Generation Neutron Residual Stress Mapping Facility (NRSF2) at Oak Ridge National Laboratory (ORNL), measuring the Fe (211) diffraction peak position of the ferrite…