Browse Topic: Reaction and response times

Items (830)

Trailer Disengage confirmation Alarm System for Electric Subsystems

2024-28-0213To be published on 12/05/2024

This paper presents a Trailer-Tractor Disengage Alarm System (TTDAS) designed to enhance safety in electrical connections between the tractor and trailer of commercial vehicles. The proposed system addresses the critical issue of unintentional disengagement of electrical connections, which can lead to hazardous situations on the road. The system employs sensor technologies and intelligent algorithms to continuously monitor the status of the electrical connection between the tractor and trailer. In the event of a disconnection, the system activates a robust alarm mechanism to promptly notify the driver, mitigating the risk of accidents and ensuring the safety of both the vehicle and other road users. Key features of the Trailer Disengage Confirmation Alarm System include real-time monitoring, rapid response time, and compatibility with various trailer configurations. The paper details the system architecture, including the integration of sensors, control units, and the alarm mechanism

Singh, Amandeep, KUMAR, Pradeep, SURESH, KARTHIKRAJAN, KOTIAN, PRADEEP, T, THIRUNAVUKKARASU, Chitreddy, Bharath, R, Sunilkumar

ACHIEVING BALANCED SYSTEMS THROUGH STRUCTURED DECISIONS

2024-01-3406

To be published on 11/15/2024

ABSTRACT To support customers during product development, General Dynamics Land Systems (GDLS) utilizes a set of Operations Research/Decision Support processes and tools to facilitate all levels of decision-making aimed at achieving a balanced system design. GDLS employs a rigorous Structured Decision (SD) process that allows for large, highly complex or strategic decisions to be made at the system-of-systems, system, and/or subsystem level. Powerful, robust tools -the Advanced Collaborative System Optimization Modeler (ACSOM) and Logical Decisions for Windows (LDW) - are used to make relatively quick assessments and provide recommendations. The latest ACSOM algorithms have increased the response time for trade study analysis by over 2,000 times and future versions will incorporate logistics analysis helping to reduce vehicle Life Cycle Cost

Gerlach, James, Hartman, Gregory, Williams, Darrell, Parent, Jeffery

HANDS-FREE, HEADS-UP CONTROL SYSTEM FOR UNMANNED GROUND VEHICLES

2024-01-3266

To be published on 11/15/2024

ABSTRACT This paper describes work to develop a hands-free, heads-up control system for Unmanned Ground Vehicles (UGVs) under an SBIR Phase I contract. Industry is building upon pioneering work that it has done in creating a speech recognition system that works well in noisy environments, by developing a robust key word spotting algorithm enabling UGV Operators to give speech commands to the UGV completely hands-free. Industry will also research and develop two sub-vocal control modes: whisper speech and teeth clicks. Industry is also developing a system that will enable the Operator to drive a UGV, with a high level of fidelity, to a location selected by the Operator using hands-free commands in conjunction with image segmentation and video overlays. This Phase I effort will culminate in a proof-of-concept demonstration of a hands-free, heads-up system, implemented on a small UGV, that will enable the Operator have a high level of fidelity for control of the system

Brown, Jonathan, Gray, Jeremy P., Blanco, Chris, Juneja, Amit, Alberts, Joel, Reinerman, Lauren

A HIGH POWER SOLID STATE CIRCUIT BREAKER FOR MILITARY HYBRID ELECTRIC VEHICLE APPLICATIONS

2024-01-3368

To be published on 11/15/2024

ABSTRACT Military vehicle electrical power systems require quickly responding fault protection to prevent mission failure, vehicle damage, or personnel injury. The electromechanical contactors commonly used for HEV protection have slow response and limited cycle life, factors which could result in fuse activation and disabling of the vehicle, presenting a dangerous situation for the soldier. A protection technology not often considered is Solid State Circuit Breakers (SSCB), which have fast response and good reliability. Challenges of extremely high currents and voltages, high temperatures, and harsh conditions have prevented SSCBs from being effective in high power military vehicle electrical systems. Development of an SSCB for military vehicle power systems would increase electrical power system capacity and expand mission capability. The development of a 1.2 kV/200A Silicon-Carbide MOSFET based SSCB for combat HEVs is presented. The key innovation is packaging that minimizes losses

Pilvelait, Bruce, Gold, Calman, Marcel, Mike

Test Cycle Simulation of Bench Based on Deep Reinforcement Learning

15-17-03-0015

07/31/2024

Test cycle simulation is an essential part of the vehicle-in-the-loop test, and the deep reinforcement learning algorithm model is able to accurately control the drastic change of speed during the simulated vehicle driving process. In order to conduct a simulated cycle test of the vehicle, a vehicle model including driver, battery, motor, transmission system, and vehicle dynamics is established in MATLAB/Simulink. Additionally, a bench load simulation system based on the speed-tracking algorithm of the forward model is established. Taking the driver model action as input and the vehicle gas/brake pedal opening as the action space, the deep deterministic policy gradient (DDPG) algorithm is used to update the entire model. This process yields the dynamic response of the output end of the bench model, ultimately producing the optimal intelligent driver model to simulate the vehicle’s completion of the World Light Vehicle Test Cycle (WLTC) on the bench. The results indicate that the

Gong, Xiaohao, Li, Xu, Hu, Xiong, Li, Wenli

Experimental Analysis of Force Recovery and Response Time Using Strain Measurement Sensors in Stress Wave Force Balance

2024-26-0451

06/01/2024

Severe problem of aerodynamic heating and drag force are inherent with any hypersonic space vehicle like space shuttle, missiles etc. For proper design of vehicle, the drag force measurement become very crucial. Ground based test facilities are employed for these estimates along with any suitable force balance as well as sensors. There are many sensors (Accelerometer, Strain gauge and Piezofilm) reported in the literature that is used for evaluating the actual aerodynamic forces over test model in high speed flow. As per previous study, the piezofilm also become an alternative sensor over the strain gauges due to its simple instrumentation. For current investigation, the piezofilm and strain gauge sensors have mounted on same stress force balance to evaluate the response time as well as accuracy of predicted force at the same instant. However, these force balance need to be calibrated for inverse prediction of the force from recorded responses. A reliable multi point calibration

Kamal, Abhishek, Deka, Sushmita, Sahoo, Niranjan, Kulkarni, Vinayak

Enhancing Safety Features of Advanced Driver Assistance System Warnings by Using Head-Up Displays

2024-01-2058

04/09/2024

ADAS (Advanced Driver Assistance Systems) is a growing technology in automotive industry, intended to provide safety and comfort to the passengers with the help of variety of sensors like radar, camera, LIDAR etc. Though ADAS improved safety of passengers comparing to conventional non-ADAS vehicles, still it has some grey areas for safety enhancement and easy assistance to drivers. BSW (Blind Spot Warning) and LCA (Lane Change Assist) are ADAS function which assists the driver for lane changing. BSW alerts the driver about the vehicles which are in blind zone in adjacent lanes and LCA alerts the driver about approaching vehicles at a high velocity in adjacent lanes. In current ADAS systems, BSW and LCA alerts are given as optical and acoustic warnings which is placed in vehicle side mirrors. During lane change the driver must see the side mirrors to take a decision. Due to this, there is a reaction time for taking a decision since driver must divert attention from windshield to side

R, Manjunath, Saddaladinne, Jagadeesh Babu, D, Gopinath

Enhanced Safety of Heavy-Duty Vehicles on Highways through Automatic Speed Enforcement – A Simulation Study

2024-01-1964

04/09/2024

Highway safety remains a significant concern, especially in mixed traffic scenarios involving heavy-duty vehicles (HDV) and smaller passenger cars. The vulnerability of HDVs following closely behind smaller cars is evident in incidents involving the lead vehicle, potentially leading to catastrophic rear-end collisions. This paper explores how automatic speed enforcement systems, using speed cameras, can mitigate risks for HDVs in such critical situations. While historical crash data consistently demonstrates the reduction of accidents near speed cameras, this paper goes beyond the conventional notion of crash occurrence reduction. Instead, it investigates the profound impact of driver behavior changes within desired travel speed distribution, especially around speed cameras, and their contribution to the safety of trailing vehicles, with a specific focus on heavy-duty trucks in accident-prone scenarios. To conduct this analysis, we utilize SUMO, an open-source microscopic traffic

Shiledar, Ankur, Sujan, Vivek, Siekmann, Adam, Yuan, Jinghui

Responses to Flashing Warning Lights and Colors of Service Vehicles

2024-01-2229

04/09/2024

Flashing warning lights and vehicle markings of various colors are used on a wide range of emergency and other service vehicles to help inform drivers about the presence of these vehicles and the types of situations that drivers are approaching. Although not applied consistently among all jurisdictions, the colors and performance of these visual elements are often selected to help communicate the type of scenario (such as red flashing lights to indicate an emergency vehicle, or yellow flashing lights to indicate a non-emergency service vehicle). Previous investigations have shown that flashing light colors, vehicle and marking colors, and flashing temporal characteristics (e.g., rapid versus slower flashing) can all affect a driver’s perception of whether a vehicle along the road is responding to an emergency situation or not. Building on previous research, a laboratory study was carried out to investigate how drivers perceive scale-model roadway scenarios including different numbers

Bullough, John D., Skinner, Nicholas P., Rea, Mark S.

Inherent Diverse Redundant Safety Mechanisms for AI-Based Software Elements in Automotive Applications

2024-01-2864

04/09/2024

This paper explores the role and challenges of Artificial Intelligence (AI) algorithms, specifically AI-based software elements, in autonomous driving systems. These AI systems are fundamental in executing real-time critical functions in complex and high-dimensional environments. They handle vital tasks like multi-modal perception, cognition, and decision-making tasks such as motion planning, lane keeping, and emergency braking. A primary concern relates to the ability (and necessity) of AI models to generalize beyond their initial training data. This generalization issue becomes evident in real-time scenarios, where models frequently encounter inputs not represented in their training or validation data. In such cases, AI systems must still function effectively despite facing distributional or domain shifts. This paper investigates the risk associated with overconfident AI models in safety-critical applications like autonomous driving. To mitigate these risks, methods for training AI

Pitale, Mandar Manohar, Abbaspour, Alireza, Upadhyay, Devesh

Trends in Driver Response to Forward Collision Warning and the Making of an Effective Alerting Strategy

2024-01-2506

04/09/2024

This paper compares the results from three human factors studies conducted in a motion-based simulator in 2008, 2014 and 2023, to highlight the trends in driver's response to Forward Collision Warning (FCW). The studies were motivated by the goal to develop an effective HMI (Human-Machine Interface) strategy that enables the required driver's response to FCW while minimizing the level of annoyance of the feature. All three studies evaluated driver response to a baseline-FCW and no-FCW conditions. Additionally, the 2023 study included two modified FCW chime variants: a softer FCW chime and a fading FCW chime. Sixteen (16) participants, balanced for gender and age, were tested for each group in all iterations of the studies. The participants drove in a high-fidelity simulator with a visual distraction task (number reading). After driving 15 minutes in a nighttime rural highway environment, a surprise forward collision threat arose during the distraction task. The response times from the

Nasir, Mansoor, Kurokawa, Ko, Singhal, Neha, Mayer, Ken, Chowanic, Andrea, Osafo Yeboah, Benjamin, Blommer, Michael

Gap Adjustment Strategy for Electromechanical Brake System Based on Critical Point Identification

2024-01-2320

04/09/2024

Abrasion of the Electromechanical brake (EMB) brake pad during the braking process leads to an increase in brake gap, which adversely affects braking performance. Therefore, it is imperative to promptly detect brake pad abrasion and adjust the brake gap accordingly. However, the addition of extra gap adjustment or sensor detection devices will bring extra size and cost to the brake system. In this study, we propose an innovative EMB gap active adjustment strategy by employing modeling and analysis of the braking process. This strategy involves identifying the contact and separation points of the braking process based on the differential current signal. Theoretical analysis and simulation results demonstrate that this gap adjustment strategy can effectively regulate the brake gap, mitigate the adverse effects of brake disk abrasion, and notably reduce the response time of the braking force output. Monitoring is critical to accurately control EMB clamping force. Pressure transducers are

Zhang, Yilong, Chen, Zixuan, Wu, Jinglai, Zhang, Yunqing

System Level Modelling, Evaluation, and Trade-Off/Optimization of Solid-State & Hybrid DC Circuit Breakers for an EV Eco-System Using AI/ML in an MBSE Framework

2024-01-2657

04/09/2024

With the increasing demand for efficient & clean transport solutions, applications such as road transport vehicles, aerospace and marine are seeing a rise in electrification at a significant rate. Irrespective of industries, the main source of power that enables electrification in mobility applications like electric vehicles (EV), electric ships and electrical vertical take-off & landing (e-VTOL) is primarily a battery making it fundamentally a DC system. Fast charging solutions for EVs & e-VTOLs are also found to be DC in nature because of several advantages like ease of integration, higher efficiency, etc. Likewise, the key drivers of the electric grid are resulting in an energy transition towards renewable sources, that are also essentially DC in nature. Overall, these different business trends with their drivers appear to be converging towards DC power systems, making it pertinent. However, DC circuit protection poses serious challenges compared to AC due to the absence of natural

Milind, T. R., Thomas, Amal, Rastogi, Sarthak, K, Satyadeep

Vehicle Braking Performance Improvement via Electronic Brake Booster

10-08-01-0005

02/10/2024

Throughout the automobile industry, the electronic brake boost technologies have been widely applied to support the expansion of the using range of the driver assist technologies. The electronic brake booster (EBB) supports to precisely operate the brakes as necessary via building up the brake pressure faster than the vacuum brake booster. Therefore, in this article a novel control strategy for the EBB based on fuzzy logic control (FLC) is developed and studied. The configuration of the EBB is established and the system model including the permanent magnet synchronous motor (PMSM), a two-stage reduction transmission (gears and a ball screw), a servo body, reaction disk, and the hydraulic load are modeled by MATLAB/Simulink. The load-dependent friction has been compensated by using Karnopp friction model. Due to the strong nonlinearity on the EBB components and the load-dependent friction, FLC has been used for the control algorithm. The control concept focused on transforming the

Soliman, Amr M.E., Kaldas, Mina M., Soliman, Aref M.A., Huzayyin, A.S.

Exploring Capabilities of Hydraulic Actuators to Achieve Vehicle Ride Targets in Frequency Range beyond Their Operational Bandwidth

2024-26-0060

01/16/2024

Active suspension systems employ sophisticated control algorithms to deliver superior comfort in vehicles. However, the capabilities of these algorithms are limited by the physical constraints of actuators. Many vehicles use hydraulic actuators in their active suspension system, which use fluid movement to control suspension motion. These systems inherently have slower response times due to the nature of fluid flow and the time required to build up or release pressure within the hydraulic system. Typically, hydraulic systems operate in a low bandwidth of 0-5 Hz. This limits their capability to only meeting vehicle’s primary ride targets which typically lie below 5 Hz. Although they can be tuned to operate at a slightly higher frequency range (up to 10 Hz), they perform poorly in attenuating the secondary ride vibration, i.e., 5 – 25 Hz. This paper focuses on investigating the possible hardware and subsequently control capabilities that can allow us to affect the vehicle ride well

Agrawal, Ayush, Negi, Ayush, Joshi, Divyanshu

Model Based Charge Control for 3-Cylinder TGDI Miller Engine Containing Variable Geometry Turbocharger

2024-26-0043

01/16/2024

For ensuring environmental safety, strong emphasis on CO2 pollution reduction is mandated which led to evolution of miller cycle engines. However, the inherent Miller engine characteristic is the lower volumetric efficiency when compared to otto engines because of which small turbo chargers with variable geometry turbines are used to induct air into the engine. With miller engine and VGT turbo charger combination arises the challenges of charge controllability because of lower inertia and reduced vane control area. With conventional turbo charger control methods, the response time is slow thereby leading to turbo lag or severe over boosting, this is overcome by accurate engine modelling and using the same as input for charger control. In this study, model-based calibration approach was performed on a 3-cylinder Miller GDI 1.2L engine to model the charge exchange of the engine and use the same for determination required turbine vane positions to achieve the desired airflow induction

Veeramani, Vivekanand, Karthi, Ramanathan, Shanmugam Ramakrishnan, Muthu

Critical Scenarios Based on Graded Hazard Disposal Model of Human Drivers

2023-01-7054

12/20/2023

In order to improve the efficiency of safety performance test for intelligent vehicles and construct the test case set quickly, critical scenarios based on graded hazard disposal model of human drivers are proposed, which can be used for extraction of test cases for safety performance. Based on the natural driving data in China Field Operational Test (China-FOT), the four-stage collision avoidance process of human drivers is obtained, including steady driving stage, risk judgment stage, collision reaction stage and collision avoidance stage. And there are two human driver states: general state and alert state. Then the graded hazard disposal model of human drivers is constructed. According to the parameter distribution of natural driving data, the risk perception point, risk response point and collision reaction time of deceleration scenario and cut-in scenario are obtained, and the deceleration gradient and the maximum deceleration of each collision avoidance difficulty level are

Fang, Xiaowei, Ma, Zhixiong, Zhu, Xichan, Yin, Qi

Analytical and Experimental Handling Performance of Ultra-Efficient Lightweight Vehicles

2023-24-0135

08/28/2023

The rising environmental awareness has led to a growing interest in electric and lightweight vehicles. Four-wheeled Ultra-Efficient Lightweight Vehicles (UELVs) have the potential to improve the quality of urban life, reduce environmental impact and make efficient use of land. However, the safety of these vehicles in terms of dynamic behaviour needs to be better understood. This paper aims to provide a quantitative assessment of the handling behaviour of UELVs. An analytical single-track model and a numerical simulation by VI-CarRealTime are analysed to evaluate the dynamic performance of a UELV compared to a city car. This analysis shows that the lightweight vehicle has a higher readiness (i.e. lower reaction time to yaw rate) for step steering and lower steering effort (i.e. higher steady-state value). Experimental analysis through real-time driving sessions on the Dynamic Driving Simulator assesses vehicle responses and subjective perception for different manoeuvres. The driving

Musso, Emanuele, Previati, Giorgio, Mastinu, Gianpiero

Predictive 3D-CFD Model for the Analysis of the Development of Soot Deposition Layer on Sensor Surfaces

2023-24-0012

08/28/2023

After-treatment sensors are used in the ECU feedback control to calibrate the engine operating parameters. Due to their contact with exhaust gases, especially NOx sensors are prone to soot deposition with a consequent decay of their performance. Several phenomena occur at the same time leading to sensor contamination: thermophoresis, unburnt hydrocarbons condensation and eddy diffusion of submicron particles. Conversely, soot combustion and shear forces may act in reducing soot deposition. This study proposes a predictive 3D-CFD model for the analysis of the development of soot deposition layer on the sensor surfaces. Alongside with the implementation of deposit and removal mechanisms, the effects on both thermal properties and shape of the surfaces are taken in account. The latter leads to obtain a more accurate and complete modelling of the phenomenon influencing the sensor overall performance. The evolution of the fouling thickness is evaluated by means of the implementation of a

D'Orrico, Fabrizio, Cicalese, Giuseppe, Breda, Sebastiano, Fontanesi, Stefano, Cozza, Ivan, Tosi, Sergio, Gopalakrishnan, Venkatesh

Occupant Kinetics and Muscle Responses of Relaxed and Braced Small Female and Midsize Male Volunteers in Low-Speed Frontal Sled Tests

09-11-03-0012

07/28/2023

Previous volunteer studies focused on low-speed frontal events have demonstrated that muscle activation (specifically pre-impact bracing) can significantly affect occupant response. However, these tests do not always include a sufficient number of small female volunteers to compare their unique responses to the typically studied midsize male population. The purposes of this study were to quantify the occupant kinetics and muscle responses of relaxed and braced small female and midsize male volunteers during low-speed frontal sled tests and to compare between muscle states and demographic groups. Small female and midsize male volunteers experienced multiple low-speed frontal sled tests consisting of two pulse severities (1 g and 2.5 g) and two muscle states (relaxed and braced) per pulse severity. The muscle activity of 30 muscles (15 bilaterally) and reaction forces at the volunteer-test buck interfaces and seat belt were measured before and during each sled test. Compared to the

Chan, Hana, Albert, Devon L., Gayzik, F. Scott, Kemper, Andrew R.

Passive Ice Protection Systems Lab Scale Testing Methodology

2023-01-1412

06/15/2023

Aircraft icing is a well-known problem that can have serious consequences for flight safety. To combat this problem, various ice protection systems (IPSs) have been developed and are currently used on most aircraft, including thermal ice protection systems. However, these systems can be costly, heavy and ineffective. Therefore, there is a need to improve the efficiency and response time of these systems. In recent years, research has focused on the development of hybrid systems that combine different ice protection technologies to achieve better performance. In this sense, the use of an active element with a coating on its external part that improve its efficiency would be an important advance, but there is a wide range of active systems and even more of coatings and surface treatments. Therefore it would be helpful to have a test methodology that would allow a simple but thorough assessment of the performance of each passive system, and this is precisely what is proposed in this

García, Paloma, Mora, Julio, Carreño, Francisco, Redondo, Francisco, Rodriguez, Rafael, Rivero, Pedro, Vicente, Adrian, Acosta, Carolina, Larumbe, Silvia, Medrano, Ángel, Lecumberri, Cristina

Experimental and Analytical Evaluation of an Acceleration-Based Semiactive Control Strategy for Automotive Suspension Systems with Magneto-Rheological Damper

15-16-03-0015

06/01/2023

Most of the control strategies presented to date are based on either the velocities or displacement of the vehicle body and the wheel which are derived by filtering and converting the data from the accelerometer. This increases the computational load and therefore directly affects the performance of the semiactive suspension system. This study presents a control strategy purely based on the acceleration for semiactive control of vehicle suspension with a magneto-rheological MR damper. The effectiveness of the acceleration-based skyhook (ASH) control strategy is compared with the existing velocity-based skyhook (VSH) control strategy based on the vibration response of a single-degree-of-freedom (SDOF) system. The effectiveness of ASH is evaluated experimentally, and the reaction time is evaluated analytically. The experimental results revealed that the ASH reduces the peak displacement and peak acceleration of the mass under the free vibration test and also improves the settling time as

Jamadar, Mohibb e Hussain, Devikiran, Pinjala, Kumar, Hemantha, Joladarshi, Sharnappa

A Road Roughness Estimation Method based on PSO-LSTM Neural Network

2023-01-0747

04/11/2023

The development of intelligent and networked vehicles has enhanced the demand for precise road information perception. Detailed and accurate road surface information is essential to intelligent driving decisions and annotation of road surface semantics in high-precision maps. As one of the key parameters of road information, road roughness significantly impacts vehicle driving safety and comfort for passengers. To reach a rapid and accurate estimation of road roughness, in this study, we develop a neural network model based on vehicle response data by optimizing a long-short term memory (LSTM) network through the particle swarm algorithm (PSO), which fits non-linear systems and predicts the output of time series data such as road roughness precisely. We establish a feature dataset based on the vehicle response time domain data that can be easily obtained, such as the vehicle wheel center acceleration and pitch rate. A PSO-LSTM network is built to achieve road roughness estimation and

Li, Zhuoyang, Yang, Shichun, Chen, Yuyi, Nan, Zhaobo, Shi, Runwu, Wang, Rui, Zhang, Mengyue

Compound Brake Control for Improved Ride Comfort for Dual-rotor In-wheel Motor Electric Vehicles

2023-01-0526

04/11/2023

Aiming at the problem of braking shock caused by the inconsistent response time of the inner motor (IM), the outer motor (OM) and the hydraulic brake when the regenerative braking mode of dual-rotor in-wheel motor (DRIWM) is switched, this paper proposes a U-shaped transition coordinated control strategy for the DRIWM. Ensure that the total braking torque can be smoothly transitioned when any one or more of the hydraulic braking torque, the braking torque of the IM and the braking torque of the OM enter/exit braking. The dynamic model of electric vehicle (EV) with DRIWMs is established, the division of braking mode is based on the principle of optimal DRIWM system efficiency, and the U-shaped transition coordinated controller of DRIWM is designed. Finally, two cases of switching the IM single braking mode to hydraulic braking mode and OM and hydraulic coordinated braking mode switching to compound braking mode are taken as examples to verify. The results show that, compared with the

leng, Fei, He, Ren

Evaluating Drivers’ Understanding of Warning Symbols Presented on In-Vehicle Digital Displays Using a Driving Simulator

2023-01-0790

04/11/2023

Since 1989, ISO has published procedures for developing and testing public information symbols (ISO 9186), while the SAE standard for in-vehicle icon comprehension testing (SAE J2830) was first published in 2008. Neither testing method was designed to evaluate the comprehension of symbols in modern vehicles that offer digital instrument cluster interfaces that afford new levels of flexibility to further improve drivers’ understanding of symbols. Using a driving simulator equipped with an eye tracker, this study investigated drivers’ understanding of six automotive symbols presented on in-vehicle displays. Participants included 24 teens, 24 adults, and 24 senior drivers. Symbols were presented in a symbol-only, symbol + short text descriptions, and symbol + long text description conditions. Participants’ symbol comprehension, driving performance, reaction times, and eye glance times were measured. The results of this study suggested that presenting automotive symbols on in-vehicle

Schwambach, Breno, Brooks, Johnell, Jenkins, Casey

Comparing Visual Fixations between Initially Stopped and In-motion Turn Across Path Hazards

2023-01-0837

04/11/2023

Collisions involving turn-across-path hazards are responsible for a disproportionate number of injuries and fatalities compared to collisions with other orientations. Previous investigations of turn-across-path hazards have found conflicting results regarding hazard detection and response behaviour of drivers, particularly for hazards with different onset conditions. Typically, hazards with abrupt onsets should attract attention more readily, however, the opposite trend for response times has been observed when the abrupt onset is a rapid change in speed, rather than a sudden appearance. This study compared two left-turn-across path hazards with different onsets. The abrupt onset hazard was an initially stopped vehicle that quickly accelerated into the participant drivers’ path, while the gradual onset hazard was already in motion as the participant driver approached. Visual fixations were compared between the two onset types to determine if the sudden speed change was capturing

Caren, Brooklin, Ziraldo, Erika, Oliver, Michele

An Analysis of Software Latency for a High-Speed Autonomous Race Car—A Case Study in the Indy Autonomous Challenge

12-06-03-0018

02/07/2023

Autonomous driving faces the difficulty of securing the lowest possible software execution times to allow a safe and reliable application. One critical variable for autonomous vehicles is the latency from the detection of obstacles to the final actuation response of the vehicle, especially in the case of high-speed driving. A prerequisite for autonomy software is that it enables low execution times to achieve superhuman reaction times. This article presents an in-depth analysis of a full self-driving software stack for autonomous racing. A modular software stack especially developed for high-speed autonomous driving is used and the latency of the software is analyzed in four main autonomy modules: perception, prediction, planning, and control. With the help of a trace point measurement method, it is possible to investigate the end-to-end latency and runtimes of the individual modules. This analysis is conducted for different scenarios (high-speed runs, object avoidance, and multi

Betz, Tobias, Karle, Phillip, Werner, Frederik, Betz, Johannes

Operational Definitions of Driving Performance Measures and Statistics

J2944_202302 (Current)

02/06/2023

This Recommended Practice, Operational Definitions of Driving Performance Measures and Statistics, provides functional definitions of and guidance for performance measures and statistics concerned with driving on roadways. As a consequence, measurements and statistics will be calculated and reported in a consistent manner in SAE and ISO standards, journal articles proceedings papers, technical reports, and presentations so that the procedures and results can be more readily compared. Only measures and statistics pertaining to driver/vehicle responses that affect the lateral and longitudinal positioning of a road vehicle are currently provided in this document. Measures and statistics covering other aspects of driving performance may be included in future editions. For eye glance-related measures and statistics, see SAE J2396 (Society of Automotive Engineers, 2007) and ISO 15007-1 (International Standards Organization, 2002

Driver Metrics, Performance, Behaviors and States Committee

Humidity Sensing Behavior and Characterization of CuWO ₄ Nanoparticles

2022-28-053712/23/2022

Solution route precipitation technique was opted to synthesize the nanostructured copper tungstate by the incorporation of cupric ion solution to the aqueous sodium tungstate reagent. The size and surface of the synthesized nanostructured material is highly influenced by the concentration of cuprous ion as well as the tungstate solution. The structural pattern and chemical composition of CuWO4 nanoparticles were analysed by powder XRD and FESEM with EDX spectrum. The powder XRD and EDX pattern confirmed the elemental composition of the synthesized samples. FESEM images indicated that the particle was present in random size distribution. At 298 K, water vapour pressure thermostat was achieved in the range from 5% to 98% as a relative humidity (RH). By providing the DC conductance measurement as a relative humidity, the humidity sensing nature of the material was investigated and the sensitivity factor (Sf) value of the prepared CuWO4 was calculated at 298K (Sf=9640±100). It revealed

S, Poovaragan, R, Ganesamoorthy, N, Balaji, K R, Padmavathi, R, Soundararajan

The Effect of Driver’s Response Features on Safety Effectiveness of Autonomous Emergency Braking

2022-01-7131

12/16/2022

The Autonomous emergency braking system (AEB) has been widely equipped in the design and manufacture of vehicles as an active safety system for preventing rear-end collisions. It has shown great safety potential in preventing collisions and reducing collision injuries. However, there are differences in the response characteristics of drivers in emergency scenarios due to individual differences and driving habits. The impact of different driver types on the safety performance of AEB systems has not been evaluated. In this study, the typical driver response model was constructed by selecting driver response features representing alertness and braking. The AEB algorithm of distance and situation awareness was combined with the kinematic of vehicle before the collision to construct a simulation case based on the rear-end collisions in the China in-depth accident study database (CIDAS). The collision avoidance percentage, the impact speed, and the minimum relative distance were used as

Wei, Tianzheng, Kang, Kai, Zhu, Tong, Liu, Haoxue

Implications for Interactions between Micromobility and Autonomous Vehicles

12-06-02-0012

12/08/2022

This article discusses the potential interactions and impacts between autonomous vehicles (AVs) and micromobility users. While fully automated privately owned AVs are not yet commercially available to the public, AVs such as robotaxis, shuttles, and delivery bots are becoming increasingly common, especially in densely populated urban areas. At the same time, new types of micromobility devices, such as e-scooters, are being introduced into the transportation infrastructure, often in the same areas. While extensive research and safety testing are standard in both domains, the potential interactions between these two types of mobility in real-world environments require consideration. By exploring the current state of both technologies and the early evidence currently available, we catalog potential implications of their interactions, particularly with respect to communication, expectations, infrastructure, risky behavior, and the impact of data limitations. Avenues for future research in

Sanders, Tracy, Karpinski, Elizabeth

On-board Electrostatic PM (ePM) Sensing for Filter IUMPR Compliance

1333210/07/2022

Recent advances in electrostatic sensing of particulates have enabled improvements in sensor response time, sensitivity, and durability. These improvements provide a path to compliance with the recently-approved CARB OBD updates phasing in between 2026 and 2029. This presentation will review the ePM measurement principle, sensor design status, performance data, calibration requirements, cold start performance, and potential applicability to real emissions assessment logging (REAL

Thompson, Patrick

Motorcycle Crash Severity Estimation for Effective Emergency Response

2022-28-0399

10/05/2022

Motorcyclists are about 29 times more likely than passenger vehicle occupants to die in a motor vehicle crash and are 4 times more likely to be injured. Safe motorcycling takes balance, co-ordination, and good judgement. As per NHTSA, per 100,000 registered vehicles motorcycle fatality and injury rate stand at 58.33 and 975 and that of passenger vehicles stand at 9.42 and 1152. With such rates of fatality and injury of motorcyclists, there is strong need for motorcycle solutions that help to minimize traffic fatalities and improve road safety scenarios. Helmets are estimated to be 37% effective in preventing fatal injuries to motorcycle riders and 41% for motorcycle passengers but there is little to no post-crash assistance available on board the motorcycles. Post-crash emergency response is time sensitive and can be broken down into a subset of activities beginning with discovery of crash, notification, and activation of emergency medical service (EMS), response time, on-scene time

Rao, Aditya N, Notani, Vipul, Muralidharan, Vishal

A Collision Avoidance Strategy Based on Inevitable Collision State

2022-01-1170

09/19/2022

This paper proposed a collision avoidance strategy that take over the control of ego vehicle when faced with urgent collision risk. To improve the applicability of collision avoidance strategy in complex scenarios, the theory of ICS (Inevitable Collision State) is introduced to evaluate the collision risk and compute the trigger flag of the system, and vehicle dynamic is taken into account when modeling ego vehicle to predict ego vehicle’s following moving. Vehicle specific characteristics including reaction time of the braking system and the braking force increasing process are taken into account. In order to reduce injury caused by collision accidents and minimize disruption to drivers, slight steering is added on top of emergency braking. The direction of the steering angle is determined according to IM (Imitating Maneuvers) The flow chart of the strategy is presented in the paper. Considering the more serious danger and higher mobility of scenarios involving VRU (Vulnerable Road

Wang, Ruoqi, Yu, Liangyao, Huang, Yong

Hand Held Aircraft Tire Inflation Pressure Gauges

ARP5542A (Current)

05/19/2022

This SAE Aerospace Recommended Practice (ARP) covers the design, construction, performance and testing requirements for hand held aircraft tire inflation pressure gauges with valve stem attachment chuck to be used with all aircraft types. The ground-based gauges in this specification are those which are designed to read the tire inflation pressure from a position adjacent to the tire

A-5C Aircraft Tires Committee

A Novel Method for Displaying Systems Datums Based on “Cognitive Load

2022-01-0808

03/29/2022

Operator attention has been a significant focus of human factors research in recent years. This research has clarified how electronic devices and other stimuli can become distractions for vehicle operators. The research has defined a condition known as “distracted driving,” characterized by interruption of the sequence of cognitive processes essential for safe operation of a vehicle. Although “attention” has been the most often mentioned of these cognitive processes, they also include perception, memory, cognition, and planful behavior. These processes are the “cognitive demands” of safe vehicle operation. There is another issue, similar to distracted driving, that may hamper safe operation of a vehicle. That issue is the “cognitive load” of human-machine interface devices, including instrument clusters. The present paper explores the effects of cognitive load on operator response speed. It describes a novel method for displaying systems datums designed to manage cognitive load. The

Havins, William

Modelling of Switching Characteristics of Hydrogen-Nitrogen Filled DC Contactor Under External Magnetic Field

2022-01-0728

03/29/2022

The electric or hybrid vehicles need fast switching operation in order to ensure the quick-response of the motors. This process is carried out by compact direct-current contactors which are designed to perform the switching over multiple cycles. During the contact separation, the gas between the contacts breaks down and the resulting thermal arc provides a conductive channel that sustains the current. Until the arc is quenched, the current continues to flow through the contacts despite the physical separation. This unintended flow of current could lead to a larger response time than the safe operation limits. We perform high-fidelity simulation of thermal arc in hydrogen-nitrogen mixture environment under external magnetic field of 1 Tesla. The hydrogen enrichment level is kept at 0%, 40%, 50% and 80%. The contacts are separated at 8 m/s. It is demonstrated that the increase in hydrogen concentration leads to smaller arc lifetime thereby improving the circuit interruption performance

Ranjan, Rakesh, Thiruppathiraj, Sudharshanaraj, Raj, Naveen, Karpatne, Anand, Breden, Douglas, Raja, Laxminarayan

Predicting Driver Emergency Response Onset using Time-to-Impact

2022-01-0806

03/29/2022

Conventional forensic analyses of collision avoidance behaviours involve assigning a perception and response time (PRT) interval to a driver which precedes the onset of evasive action. This approach relies on the investigator identifying a ‘time zero’ for when to begin the PRT interval, which nominally aligns with the first moment of hazard detection. However, depending on the incident circumstances, identifying the initial moment of hazard detection poses challenges. Recent research has shown the potential of an alternative method of forensic analysis that is based on the relationship between response onset and the projected time-to-impact (TTI). Accordingly, the aim of this research is to further investigate this relationship. Twenty subjects viewed driver-perspective recordings of a simulated vehicle travelling down a major roadway past several two-way stop-controlled minor roads. At various intersections, intruding vehicles entered from the left or right. These intruders were

Erazo, Fabian, Campbell, Adam

Hydrostatic Torque Modulation

2022-01-0643

03/29/2022

Hydrostatic torque modulation is a new, at moment theoretical approach, to developing advanced AWD4WD transmissions. The basic component is a rotational hydrostatic modulator. It is derived from a low-speed high-torque hydrostatic machine. As such, it can be integrated into a standard mechanical AWD4WD transmission as a replacement for the clutch, where torque is controlled through energy dissipation. Controlled by a simple solenoid valve, it provides torque vectoring with a reaction time shorter than 0.5 s, and it provides additional safety features that result in a more robust AWD4WD transmission. As it can modulate torque with energy flow control/transfer, it offers much more than existing systems based on controlled clutches. Specifically, hydrostatic torque modulation, when it is integrated into the AWD4WD transmission, brings CVT or ICT performance. As torque modulation is performed through the control of the energy flow, it provides torque control from 0 km/h without using a

Bozic, Ante

One Systematic Design Method and Control Performance Evaluation of Heading Control System in Pleasure Boats

2022-32-0086

01/09/2022

The pleasure boat intended in this paper is an outboard motor boat equipped with an outboard motor operating a propeller thrust and a steering angle. Outboard motor boats have a wide variation in the number of outboard motors to be equipped with depending on the size and a shape of the boat itself, and the environmental disturbances peculiar to a boat such as tidal currents and winds greatly influences the heading control performance. Therefore, it is necessary to realize a robust heading control response to environmental disturbances regardless of the variation of boats. There are two challenges for realizing such heading control response. One challenge is ensuring the stability of the control system in the entire speed region from the low-speed region for fishing applications to the high-speed region for mobile applications to which the autopilot function is applied. The other one is the suppression of the deviation in the response time of the heading control response. In response to

Imamura, Naoki, Sakaguchi, Ryo

Algorithm Flies Drones Faster than Human Racing Pilots

TBMG-4046612/01/2021

To be useful, drones need to be quick. Because of their limited battery life, they must complete whatever task they have — searching for survivors on a disaster site, inspecting a building, or delivering cargo — in the shortest possible time. And they may have to do it by going through a series of waypoints like windows, rooms, or specific locations to inspect, adopting the best trajectory and the right acceleration or deceleration at each segment

SAE TOMORROW TODAY: Empowering Superheroes: Emergency eVTOL Aircraft from Start-Up Jump Aero

1317311/29/2021

In emergency situations, every second counts - but long distances to rural areas and congested city traffic often increase the time it takes to transport a patient to a hospital. Jump Aero is mobilizing eVTOL aircraft as a solution to cut emergency response time in half and save thousands of lives. Co-founders Carl Dietrich, President/Chief Designer, and Katerina Barilov, Head of Business Development, discuss their passion for the Jump Aero mission. Hear more about how electric aircraft can reduce the time it takes to get a responder on the scene, why their EMTs are required to learn how to fly an airplane, and how their commitment to engage with EMS communities builds partnerships and trust. Stay up to date on the latest news from Jump Aero: https://www.jumpaero.com

Hineman, Marcie

Development of Thermal Detection Device for Automotive Vehicles to Monitor Human Body Heat

2021-26-0232

09/22/2021

According to research studies, epidemics such as SARS, COVID-19 spread have caused huge negative impacts on population, health and the economy around the globe. The outbreak places a huge burden on international health systems that were already straining to address AIDS, tuberculosis, malaria, and a host of other conditions. Research has proven that incase infected person is not traced timely then the spread of infection in society will take the shape of large-scale community transmission. Most of the infections spread because they got unnoticed by the infected person. One part of the access checker scans is a person’s body temperature by measuring infrared radiation emitted by their skin. Fever screening by infrared thermal imaging has become more widespread following the SARS infection, and particularly during the pandemic H1N1 and COVID-19 outbreak. Skin temperature is measured without contact by monitoring the emitted infrared radiation. The infrared thermal camera that monitors

Pajgade, Sachin Madhukarrao, Bhargava, Aashish

Prediction of Biodiesel Production from Sardine Fish Oil Methyl Ester Using Microwave Assisted Transesterification Method Using Response Surface Methodology

2021-01-1202

09/21/2021

This study presents a demonstration of generating biodiesel from fish oil utilising microwave with a significant reduction in the amount of catalyst needed during the reaction and the time of reaction. Various factors such as microwave power, catalyst concentration, reaction duration, and molar ratio were tested experimentally. The response surface approach was used to improve the reaction parameters. As reaction parameters, four levels were chosen: molar ratio, catalyst concentration, and reaction time. According to the RSM model results, molar ratio has a crucial role in the transesterification of fish oil to bio diesel. Confirmatory tests were carried out to validate the acquired data, and they proved to be worthwhile

Sathyamurthy, Ravishankar, CHANDRA SEKHAR, S., Venkatesan PhD, M

Co-Simulation of BLDC Motor Control and Clutch Actuation System with Ball Ramp Mechanism

2021-01-123609/21/2021

Electro-mechanical actuators are widely used in different forms in the automotive industry these days and are very effective in translating rotary motion of the motor to a linear motion with precision as per the requirement. With onset of electric drivelines and other complex driveline configurations, there is an increase in actuator applications. In this study, high fidelity analytical model was developed for a ball ramp clutch actuation system as per the proposed mechanical design and the software controls. The controls architecture is built in SIMULINK environment to drive the plant model of the BLDC motor. Whereas, the entire mechanical system which includes the gear train, ball ramp mechanism, clutch pack stiffness, etc. is modelled in ADAMS tool. The Ball Ramp consists of metal balls positioned in between opposing paired arc-shaped ramp grooves and guided by a cage to keep them equally separated in the same plane. While ADAMS model deals with high-fidelity contact dynamics using

Rajendran, Raveen K., Roy, Nantu, Mehta, Yogesh

Personal Protective Devices for Toxic and Irritating Atmospheres Air Transport Flight Deck (Sedentary) Crewmembers

AS8031A (Current)

08/11/2021

This SAE Aerospace Standard (AS) covers any protective system that serves the stated purpose

A-10 Aircraft Oxygen Equipment Committee

Road Projections: Impact on Road Users and Potential to Enhance Awareness of Backing Situation in Parking Lots

2021-01-5078

07/28/2021

Road projections, i.e., light projections on the road surface of patterns, lanes, symbols, pictograms, or text, represent a very promising feature for automotive lighting to support the communication between vehicles and human road users and to attract users’ attention and awareness in given situations. Nevertheless, such advanced functions are still under discussion, and it should be assessed, regardless of the lighting technologies, if they can actually benefit the safety of road users. Indeed it has to be investigated whether such road projections can provide a clear and relevant message to road users in a specific usage context and if this can result in awareness of the situation, anticipation, and adoption of safe behaviors. Within this scope, this paper presents a research work to investigate the impact of road projections on road users’ behaviors in a specific use-case, i.e., a backing situation in a parking lot. The study was conducted as an observational study by testing

Azouigui, Sheherazade, Saudrais, Sebastien, Barbedette, Bertrand, Bordel, Stephanie, Delauzun, Sylvia, Khatir, Basile, Neumann, Cornelius, Jahn, Patric, Balembois, François, Jaillette, Philippe

Effects of Situational Urgency on the Perception and Response Time to Lateral Collision Hazards

2021-01-0857

04/06/2021

Situational urgency influences the perception and response time (PRT) interval of drivers confronting emergency collision hazards. However, a gap exists in our understanding of the movement characteristics of a collision hazard that directly contribute to a driver’s decision to initiate an evasive response. The aim of this experiment is to examine how the movement characteristics of intruding vehicles affect an oncoming driver’s PRT interval. Fourteen subjects viewed first-person perspective recordings of a simulated vehicle travelling along a two-lane roadway. Collision hazards were introduced when stopped vehicles positioned at intersecting roadways unexpectedly intruded into the subject’s path. Subjects were instructed to ‘brake’ their vehicle by pressing a keyboard space bar when they perceived that evasive actions were required to avoid a collision. The duration of the PRT interval was considered as the time between the start of the intruder’s motion and when the ‘brake’ was

Erazo, Fabian, Campbell, Adam

Factors that Influence Drivers’ Responses to Slower-Moving or Stopped Lead Vehicles

2021-01-0890

04/06/2021

Rear-end crashes account for more than one in five fatal crashes in the U.S. The rear-end crash scenario most commonly associated with fatal crashes involves a following vehicle traveling 40 to 70 mph closing on a lead vehicle at a rate greater than 30 mph. The current research compiled an analysis of the literature to identify the kinematic factors, environmental factors, traffic-related factors and individual differences that are likely to influence drivers’ responses when closing on a slower-moving or stopped lead vehicle [LV]. In Part 1, several primarily kinematic-based methods for modeling drivers’ responses to a LV were compared for high-speed closing events. Methods utilizing looming (angular growth rate) equations were shown to predict drivers’ responses and time-to-contact methods (Inverse Tau) were conditionally accurate when applied to specific crash scenarios. However, the ratio or nominal response time methods did not predict drivers’ responses in most crash scenarios

Muttart, Jeffrey, Kuzel, Michael, Dinakar, Swaroop, Gernhard - Macha, Suntasy, Edewaard, Darlene E., Appow, Stephanie, Dickson, Connor

A Research on Modeling and Pressure Control of Integrated Electro-Hydraulic Brake System

2021-01-0130

04/06/2021

A fourth-order mathematical model for I-EHB (integrated electro-hydraulic brake) system was derived from its mechanical and hydraulic subsystems. The model was linearized at equilibrium state and then was verified by AMESIM software. The friction model of the system was analyzed based on static friction and viscous friction. A bench test was designed to identify the parameters of friction model. As the I-EHB system worked at different braking conditions, a PID-based switching controller was designed to track the target servo cylinder pressure. Both simulations and experiments results showed that, the response time of pressure was less than 120ms, and there was no overshoot, which helped handling different braking conditions and improving the braking safety and comfort

Wang, Bing, Wang, Minghui, Jiang, Yongfeng, Shangguan, Wen-Bin

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