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Iterative Dynamic Programming Based Model Predictive Control of Energy Efficient Cruising for Electric Vehicle with Terrain Preview

Nanjing University of Science and Technology-Fei Ju, Liangmo Wang, Qun Wang
Southeast University-Weichao Zhuang
  • Technical Paper
  • 2020-01-0132
To be published on 2020-04-14 by SAE International in United States
As a global optimization method, dynamic programming (DP) can be employed to seek the optimal velocity with minimum energy consumption for EV on given driving cycles. Due to its terrible computational burden, conventional DP is not suitable for real-time implementation especially with higher dimensions. In this paper, we propose an iterative dynamic programming (IDP) approach to reduce computing time firstly. The IDP can obtain the optimal control laws alike the conventional DP by converging the optimal control strategy iteratively and save considerable computing time. Second, the developed IDP and model predictive control (MPC) are combined to establish a real-time cruising controller called IDP-MPC for an EV with terrain preview. In the predictive controller, we use the IDP to solve a constrained finite horizon nonlinear optimization problem. Finally, to assess the performance of the proposed cruising controller, simulation on a realistic urban expressway road terrain is implemented. Energy-saving potential of the IDP-MPC controller is explored by comparing to DP and constant speed (CS) cruising controllers. The comparative study indicates that the IDP-MPC controller can obtain near-optimal…
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Method for Modeling Line-of-Sight Blockage of Aircraft Noise

A-21 Aircraft Noise Measurement Aviation Emission Modeling
  • Aerospace Standard
  • AIR6501
  • Current
Published 2020-02-20 by SAE International in United States
This document describes methods for calculating the attenuation of sound due to line-of-sight blockage or shielding from non-level terrain. This method applies to sound propagating from an airplane to locations on the ground during ground roll, climbout after liftoff, and landing operations. AIR1845 and AIR5662 provides guidance for modeling aircraft noise at airports with flat terrain. In reality, many airports are surrounded by non-level terrain that may result in attenuation (or shielding) of sound at some receptors. This noise blockage can be accounted for with the line-of-sight blockage calculation, based on the difference in propagation path length between the direct path and propagation path over the top of terrain feature. The purpose of this aircraft information report is to provide a method that accounts for the attenuation due to line-of-sight blockage of aircraft noise by terrain features.
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Robot Performs Complex Maneuvers

  • Magazine Article
  • TBMG-35830
Published 2020-01-01 by Tech Briefs Media Group in United States

At a height of less than a foot, Salto (saltatorial locomotion on terrain obstacles) the robot can vault over three times its height in a single bound. First introduced in 2016, Salto now can bounce in place and jump through obstacle courses, potentially leaping through rubble to aid in search-and-rescue missions.

Low-Bandwidth Radar Technology Provides Improved Detection of Objects

  • Magazine Article
  • TBMG-35690
Published 2019-12-01 by Tech Briefs Media Group in United States

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.

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Development of a Simulation Model for Computing Stable Configurations for Off - Road Vehicle

Piyush Kailash Malviya
John Deere India Pvt. Ltd.-Vinit Shashikant Jawale, Ojas Patil, Ameya Bandekar
Published 2019-10-11 by SAE International in United States
Off-highway vehicles operate under complex duty cycles which consist of handling varying terrain conditions under dynamic loads. A challenge for the equipment operator is to maintain stability of the vehicle during various field operations. The operator must make judgment calls on whether terrain and loading conditions are suitable for vehicle stability. In view of the increasing emphasis being placed on operator comfort and vehicle autonomy, a methodology to predict the degree of vehicle stability in varying terrains and dynamic loads will be an aid in designing safer vehicles. This paper describes a mathematical model capable of predicting the longitudinal overturning behavior of off-highway vehicle. A mathematical kinematic and dynamic model of the system is developed using Newton-Euler approach. This yields a system of non-linear equations which can be solved iteratively by using any commercial software to predict stability for varying terrains and dynamic loads. Given a vehicle geometry and terrain conditions, this methodology allows the simulation and prediction of various longitudinal overturning situations under dynamic loading. The modularity and scalability of the methodology will allow…
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SnowMicroPenetrometer Applications for Winter Vehicle Mobility

  • Magazine Article
  • TBMG-35361
Published 2019-10-01 by Tech Briefs Media Group in United States

The U.S. Engineer Research and Development Center (ERDC) Military Engineering Program on Remote Assessment of Infrastructure for Ensured Maneuver (RAFTER) Boreal Aspects of Ensured Maneuver (BAEM) identifies the need for modeling over-snow vehicle performance, as many factors related to vehicle setup and land surface condition contribute to vehicle efficiency. Accurately estimating snow macromechanical characteristics—such as elastic modulus, stiffness, and strength—is critical for understanding how effectively a vehicle will travel over snow-covered terrain.

Green’s Function Extraction from Atmospheric Acoustic Propagation

  • Magazine Article
  • TBMG-35363
Published 2019-10-01 by Tech Briefs Media Group in United States

Acoustic waves propagating in the atmosphere may undergo many effects including refraction by temperature and wind velocity gradients, scattering by atmospheric turbulence, absorption by the atmosphere (fluid), diffraction by terrain features, and absorption and reflection by a porous ground. As a result, there may be insonification in acoustic shadow zones, amplitude and phase fluctuations of the propagating sound signals, loss of signal coherence, changes in the interference maxima and minima of the direct ground reflected waves, and multipath effects. Understanding these effects is important for a variety of military applications, such as acoustic source localization and classification, noise propagation in the atmosphere, and the development of new remote sensing techniques of the atmosphere.

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SnowMicroPenetrometer Applications for Winter Vehicle Mobility

Aerospace & Defense Technology: October 2019

  • Magazine Article
  • 19AERP10_10
Published 2019-10-01 by SAE International in United States

Characterizing the mechanical properties of snow and their impact on vehicle performance could improve vehicle winter mobility modeling.

The U.S. Engineer Research and Development Center (ERDC) Military Engineering Program on Remote Assessment of Infrastructure for Ensured Maneuver (RAFTER) Boreal Aspects of Ensured Maneuver (BAEM) identifies the need for modeling over-snow vehicle performance, as many factors related to vehicle setup and land surface condition contribute to vehicle efficiency. Accurately estimating snow macromechanical characteristics-such as elastic modulus, stiffness, and strength-is critical for understanding how effectively a vehicle will travel over snow-covered terrain.

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Geospatial Accuracy of Small Unmanned Airborne System Data in the Coastal Environment

  • Magazine Article
  • TBMG-34330
Published 2019-05-01 by Tech Briefs Media Group in United States

The purpose of this study was to assess the ability of commonly available COTS software to produce geometrically accurate orthometric mosaics and terrain models from low-altitude UAS imagery.

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Geospatial Accuracy of Small Unmanned Airborne System Data in the Coastal Environment

Aerospace & Defense Technology: May 2019

  • Magazine Article
  • 19AERP05_06
Published 2019-05-01 by SAE International in United States

Determining the performance of image processing software could lead to better data collection strategy.

The purpose of this study was to assess the ability of commonly available COTS software to produce geometrically accurate orthometric mosaics and terrain models from low-altitude UAS imagery.

Annotation ability available