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Development of low cost life saving system for Automotive vehicles during Road Accidents.

Tata Technologies, Ltd.-Sachin Madhukarrao Pajgade
  • Technical Paper
  • 2019-28-2460
To be published on 2019-11-21 by SAE International in United States
According to research study 45% of death cause due to not getting help on time to the injured person. Research has proven that if injured person is not found any option of help then they also loose the power to fight such critical situation due to psychological effect. When vehicle met accident, people are not getting on time support, this delay is the major cause of death in developing nations. Presently there is no any robust system available in market for passenger & commercial vehicles which helps to provide on time help to the injured persons & saves human life. In current situation low cost life saving device is need of our society. This paper deals with the design & development of the low cost-life saving device. This paper also comprises the scenario when any vehicle meet an accidents within certain speed limit then how the intelligent life saving device will work & save the life's. Further it explains the type of life saving device design, logical programming and system packaging. The system has been…
 

Transient Response Analysis and Synthesis of an FSAE Vehicle using Cornering Compliance

SRM Institute Of Science And Technology-Vasanthkumar CH, Shubham Subhnil, Pranav Suresh, K Kamalakkannan
SRM Institute of Science & Technology-Nanthakumar Ajd
  • Technical Paper
  • 2019-28-2400
To be published on 2019-11-21 by SAE International in United States
OBJECTIVE Race vehicles are designed to achieve higher lateral acceleration arising at cornering conditions. A focused study on the steady state handling of the car is essential for the analysis of such conditions. The transient response analysis of the car is also equally important to achieve best driver-car relationship and to quantify handling in the range suitable for a racing car. This research aims to investigate the design parameters responsible for the transient characteristics and optimize those design parameters. This research work examines the time-based analysis of the problem to truly capture the non-linear dynamics. Apart from tires, chassis can be tuned to optimize vehicle handling and hence the response times. METHODOLOGY To start with, the system is modelled with governing parameters and simulation is carried out to set baseline configurations. Steady state and transient handling simulations run independent of each other with independent logic, coded on MATLAB. The static testing of the chassis is carried over using a Kinematic & Compliance (K & C) testing rig to get Compliance Budget and hence the calculated…
 

HANDLING EXCEPTIONAL SITUATION OF AN AUTONOMOUS VEHICLE

General Motors Technical Center India-Balasab Kardegouda
  • Technical Paper
  • 2019-28-2526
To be published on 2019-11-21 by SAE International in United States
In autonomous vehicle world human safety takes highest priority. And most researchers agree that machines won't be able to completely take over driving duties for years or even decades. "Today's autonomous vehicles can drive relatively well in typical settings, but they fail in exceptional situations - and it's those situations that are the most dangerous," said Walter Lasecki, an assistant professor of computer science and engineering. "Designing autonomous systems that can handle those exceptional situations could take decades, and in the meantime, we're going to need something to fill the gap. Few companies have introduced human safety drivers in autonomous vehicles which has cost advantage compared to traditional ride sharing services. Combining human and artificial intelligence in autonomous vehicles could push driverless cars more quickly toward wide - scale adoption. The aim of this paper is to showcase serial data architecture of high speed data transfer of critical predicted vehicle data of an exceptional situations, both onboard and offboard. This data shall be used for instantaneous analysis and decision making during exceptional situations. According to…
 

Optimal Engine Re-Start Strategy on a Mild Hybrid Powertrain by Means of Up-Front Modelling

Ford Werke GmbH-Harald Stoffels, Shan-An Kao, Michael Frenken
  • Technical Paper
  • 2019-24-0206
To be published on 2019-09-09 by SAE International in United States
The ability to switch off the internal combustion engine (ICE) during vehicle operation is a key functionality in hybrid powertrains to achieve low fuel economy. However, this can affect driveability, namely acceleration response when an ICE re-engagement due to a driver initiated torque demand is required. The ICE re-start as well as the speed and load synchronisation with the driveline and corresponding vehicle speed can lead to high response times. To avoid this issue, the operational range where the ICE can be switched off is often compromised, in turn sacrificing fuel economy. Based on a 48V off-axis P2 hybrid powertrain comprising a lay-shaft transmission we present an up-front simulation methodology that considers the relevant parameters of the ICE like air-path, turbocharger, friction, as well as the relevant mechanical and electrical parameters on the hybrid drive side, including a simplified multi-body approach to reflect the relevant vehicle and powertrain dynamics. Applying different ICE re-start strategies at different speeds and gears, the driveability of the ICE re-engagement was evaluated using a commercialized driveability evaluation tool. The objective…
 

Quantification of Linear Approximation Error for Model Predictive Control of Spark-Ignited Turbocharged Engines

Clemson University-Rohit Koli, Daniel Egan, Qilun Zhu, Robert Prucka
  • Technical Paper
  • 2019-24-0014
To be published on 2019-09-09 by SAE International in United States
Modern turbocharged spark-ignition engines are being equipped with an increasing number of control actuators to meet fuel economy, emissions, and performance targets. The response time variations between engine control actuators tend to be significant during transients and necessitate highly complex actuator scheduling routines. Model Predictive Control (MPC) has the potential to significantly reduce control calibration effort as compared to the current methodologies that are based on decentralized feedback control strategies. MPC strategies simultaneously generate all actuator responses by using a combination of current engine conditions and optimization of a control-oriented plant model. To achieve real-time control, the engine model and optimization processes must be computationally efficient without sacrificing effectiveness. Most MPC systems intended for real-time control utilize a linearized model that can be quickly evaluated using a sub-optimal optimization methodology. Online linearization of the engine model is computationally expensive so it should be performed as infrequently as possible. Since engine dynamics are non-linear, a local linearity approximation error occurs during this process. This research presents a method of evaluating the impact of local linear approximation…
 
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Factors Affecting the Severity of Motor Vehicle Traffic Crashes in Tunisia

SAE International Journal of Transportation Safety

Najran University, Saudi Arabia-Mounir Belloumi
University of Sousse, Tunisia-Fedy Ouni
  • Journal Article
  • 09-07-01-0006
Published 2019-08-19 by SAE International in United States
We investigate the contribution of several variables concerning the severity of accidents involving vehicle occupant and pedestrian victims in Tunisia. In order to investigate the effect of various explanatory variables, Odds Ratio (OR) effects are considered for both serious injury accidents and fatal accidents. The empirical results are of great variety. The vehicle-occupant severity model indicates that male drivers are associated with higher severity levels as compared to female drivers. Added to that, accidents occurring in rainy conditions increase the likelihood of fatal injuries but have no significant effect on other injury severity levels. Among driver contributory factors, a driver under the influence of alcohol or drug is associated with an increased risk of sustaining fatal injuries compared to other driver contributory factors. The season factor shows that accident severity during the summer season is high. Among time of accident, daytime periods indicate a high likelihood of severe injuries as compared to nighttime periods. Another finding of the study is that the day of accident and region of accident increases the probability of severe injury.…
 

Driving Simulator Performance in Charcot-Marie-Tooth Disease Type 1A

SAE International Journal of Transportation Safety

University of Iowa Carver College of Medicine, USA-Nivedita U. Jerath, Nazan Aksan, Jeffrey D. Dawson, Michael E. Shy
University of Nebraska Medical Center, USA-Matthew Rizzo
  • Journal Article
  • 09-07-01-0003
Published 2019-05-10 by SAE International in United States
Introduction: This study evaluates driving ability in those with Charcot-Marie-Tooth Disease Type 1A, a hereditary peripheral neuropathy. Methods: Individuals with Charcot-Marie-Tooth Disease Type 1A (n = 18, age = 42 ± 7) and controls (n = 19; age = 35 ± 10) were evaluated in a driving simulator. The Charcot-Marie-Tooth Neuropathy Score version 2 was obtained for individuals. Rank Sum test and Spearman rank correlations were used for statistical analysis. Results: A 74% higher rate of lane departures and an 89% higher rate of lane deviations were seen in those with Charcot-Marie-Tooth Disease Type 1A than for controls (p = 0.005 and p < 0.001, respectively). Lane control variability was 10% higher for the individual group and correlated with the neuropathy score (rS = 0.518, p = 0.040), specifically sensory loss (rS = 0.710, p = 0.002) and pinprick sensation loss in the leg (rS = 0.490, p = 0.054). Discussion: Driving simulator assessment demonstrated more lane control errors in those with Charcot-Marie-Tooth Disease Type 1A, which correlated with lower extremity sensory loss. There was…
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Prediction and Control of Response Time of the Semitrailer Air Braking System

SAE International Journal of Commercial Vehicles

Jiangsu University, China-Ren He, Chang Xu
  • Journal Article
  • 02-12-02-0011
Published 2019-05-09 by SAE International in United States
The response time of the air braking system is the main parameter affecting the longitudinal braking distance of vehicles. In this article, in order to predict and control the response time of the braking system of semitrailers, an AMESim model of the semitrailer braking system involving the relay emergency valve (REV) and chambers was established on the basis of analyzing systematically the working characteristics of the braking system in different braking stages: feedback braking, relay braking, and emergency braking. A semitrailer braking test bench including the brake test circuit and data acquisition system was built to verify the model with typical maneuver. For further evaluating the semitrailer braking response time, an experiment under different control pressures was carried out. Experimental results revealed the necessity of controlling the response time. As a result, a braking pressure compensation system was designed through adding intake and exhaust solenoid valves to the original braking system. A proportional-integral-derivative (PID) control strategy optimized by genetic algorithm (GA) was adopted to generate pulse width modulation (PWM) signals applied to the solenoid valves…
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Evaluation of Different ADAS Features in Vehicle Displays

University of Michigan-Abhishek Mosalikanti, Pranove Bandi, Sang-Hwan Kim
Published 2019-04-02 by SAE International in United States
The current study presents the results of an experiment on driver performance including reaction time, eye-attention movement, mental workload, and subjective preference when different features of Advanced Driver Assistance Systems (ADAS) warnings (Forward Collision Warning) are displayed, including different locations (HDD (Head-Down Display) vs HUD (Head-Up Display)), modality of warning (text vs. pictographic), and a new concept that provides a dynamic bird’s eye view for warnings.Sixteen drivers drove a high-fidelity driving simulator integrated with display prototypes of the features. Independent variables were displayed as modality, location, and dynamics of the warnings with driver performance as the dependent variable including driver reaction time to the warning, EORT (Eyes-Off-Road-Time) during braking after receiving the warning, workload and subject preference. The primary results were in line with previous research, validating previous claims of the superiority of HUD over HDD in warning delivery. It was also found that the text format of the warning yielded higher response rates along with lower workload, while most participants preferred the dynamic bird’s eye view layout.
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Automated Vehicle Disengagement Reaction Time Compared to Human Brake Reaction Time in Both Automobile and Motorcycle Operation

Dynamic Analysis Group LLC-Jeffrey T. Dinges, Nicholas J. Durisek
Published 2019-04-02 by SAE International in United States
Autonomous Vehicle Disengagement Reports have been published by the California Department of Motor Vehicles since 2015. The State of California autonomous vehicle testing regulations require every manufacturer authorized to test autonomous vehicles on public roads to submit an annual report summarizing disengagements. In early versions of the annual report, automated vehicle manufacturers were required to provide the time that it took for a human driver to take manual control of the vehicle when reporting vehicle disengagements. This study analyzes reported automated vehicle disengagement reaction times from 2015 through 2017 for various manufacturers that provided information to the California Department of Motor Vehicles while operating vehicles in autonomous mode. This study compares the reported automated vehicle operation disengagement reaction time to field literature in testing and experimentation on human brake reaction times for both automobile and motorcycle operation.
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