Your Selections

Road tests
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Investigation of the Effect of Tire Deformation on Open-Wheel Aerodynamics

Graz University of Technology-Philipp Eder, Cornelia Lex
U.A.S. Graz-Thomas Gerstorfer, Thomas Amhofer
  • Technical Paper
  • 2020-01-0546
To be published on 2020-04-14 by SAE International in United States
This paper introduces a finite element (FE) approach to determine tire deformation and its effect on open-wheeled racecar aerodynamics. In recent literature the tire deformation was measured optically using cameras during wind tunnel testing. Combined loads like accelerat-ing at corner exit are difficult to reproduce in wind tunnels and would require several camer-as to measure the tire deformation. In contrast, an FE approach is capable of determining the tire deformation in combined load states accurately and additionally provides the possibility to vary further parameters, for example, the coefficient of friction. The FE tire model was validated using stiffness measurements, contact patch measurements and steady-state cornering measurements on a flat belt tire test rig. The deformed shape of the FE model was used in a computational fluid dynamics (CFD) simulation. A sensitivity study was created to determine the effect of the tire deformation on aerodynamics for un-loaded, purely vertically loaded and combined vertical, lateral and longitudinal forces. In addition, the influence of these three tire deformations was investigated in a CFD study using a full vehicle…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Co-Simulation Platform for Powertrain Controls Development

Hyundai-Kia America Technical Center Inc.-Shihong Fan, Yong Sun, Jason Hoon Lee, Jinho Ha
  • Technical Paper
  • 2020-01-0265
To be published on 2020-04-14 by SAE International in United States
With the advancement of simulation software development, the efficiency of vehicle and powertrain controls research and development can be significantly improved. Traditionally, during the development of a new control algorithm, dyno or on-road testing is necessary to validate the algorithm. Physical testing is not only costly, but also time consuming. In this study, a virtual platform is developed to reduce the effort of testing. To improve the simulation accuracy, co-simulation of multiple software is suggested as each software specializes in certain area. The Platform includes Matlab Simulink, PTV Vissim, Tass Prescan and AVL Cruise. PTV Vissim is used to provide traffic environment to PreScan. PreScan is used for ego vehicle simulation and visualization. Traffic, signal and road network are synchronized in Vissim and PreScan. Powertrain system is simulated in Cruise. MATALB/Simulink serves as master of this co-simulation, and integrates the different software together. It also includes human driver model and a powertrain control function. An ADAS-ISG (Idle Stop and Go) powertrain control algorithm is implemented in Simulink and tested by using the platform under different…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental-numerical correlation of a multi-body model for comfort analysis of an heavy truck

CNH Industrial-Andrea Morello, Vladi Nosenzo, Enrica Capitelli
Politecnico di Torino-Enrico Galvagno, Michele Galfrè, Mauro Velardocchia
  • Technical Paper
  • 2020-01-0768
To be published on 2020-04-14 by SAE International in United States
In automotive market, today more than in the past, it is very important to reduce time to market and, mostly, developing costs before the final production start. Ideally, bench and the on-road tests can be replaced by multi-body studies because virtual approach guarantees test conditions very close to reality and it is able to exactly replicate the standard procedures. Approval authorities are starting to look at simulations to release homologation certificates. Therefore, today, it is essential to create very reliable models, able to forecast the vehicle behavior on every road condition (including uneven surfaces). The aim of this study is to build a reliable multi-body model of a heavy commercial vehicle and to correlate experimental and numerical data related to comfort analysis for validation purposes. Experimental results are recorded during tests carried out at different speeds and loading conditions on a Belgian blocks track. Simulation data are obtained reproducing the on-road test conditions in multi-body environment. The virtual vehicle is characterized by rigid and flexible bodies, the tire model used is FTire (Flexible Structure Tire…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Gear Shifting Indication Strategy of Eco-driving Vehicle

Jiangsu University-Nannan Hu
Jiangsu University-Ren He
  • Technical Paper
  • 2020-01-0966
To be published on 2020-04-14 by SAE International in United States
The current indication strategy of gear shifting indication system for manual transmission vehicles is developed based on the gear shifting strategy of the automatic transmission. In this paper, the driving data of several automatic transmission and manual transmission vehicles are collected. It is found that the shifting frequency of automatic transmission vehicles is significantly higher than that of manual transmission vehicles, which increases the fatigue of drivers. Aiming at this problem, an interval algorithm of gear shifting indication strategy is proposed based on the fuel consumption rate of engine in this paper. The strategy uses genetic algorithm to process the data of fuel consumption rate, finding the maximum and minimum values in the interval of torque and engine speed, and then the interval algorithm is adopted to transform the search of least fuel consumption value into the seeking of optimal interval to avoid the shifting busyness caused by the sudden change of the data of fuel consumption rate. The model of gear shifting indication strategy is established in Matlab/Simulink. Gear shifting tolerance is defined and…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Real-world Emission Analysis Methods Using Sensor-based Emission Measurement System

Ibaraki University-Kotaro Tanaka
NGK Spark Plug Co., Ltd.-Takeshi Tange
  • Technical Paper
  • 2020-01-0381
To be published on 2020-04-14 by SAE International in United States
Every year, due to exhaust gas regulations that are getting stricter, the average air pollution is going to be solved, but the local roadside pollution is still pressing issue. In order to solve this local roadside pollution problem, it is necessary to evaluate and/or predict “where” and “how much” pollutants such as NOx are emitted. In recent years, Real Driving Emission regulations using PEMS (Portable Emission Measurement System) have been introduced mainly in Europe. However, PEMS has a configuration close to 100 kg, and its weight affects the driving conditions of vehicles running on actual roads. In this study, we focused on the analysis of real world emissions using SEMS (Sensor-based / Simple Emission Measurement System). Whereas PEMS is a method of sampling and analyzing exhaust gas, SEMS directly attaches NOx sensor and PM sensor to the exhaust pipe and measures the concentration. Although SEMS has a limited number of items that can be measured compared to PEMS, other analyzes are possible by devising the analysis method. This paper focuses on the analysis method of…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

An Experimental Methodology for Measuring Resistance Forces of Light-Duty Vehicles under Real-World Conditions and the Impact on Fuel Consumption

Aristotle University of Thessaloniki-Dimitrios Komnos, Leonidas Ntziachristos
European Commission Joint Research-Georgios Fontaras, Jelica Pavlovic, Biagio Ciuffo
  • Technical Paper
  • 2020-01-0383
To be published on 2020-04-14 by SAE International in United States
A key element of any vehicle-certification test is the use of representative values for the vehicle resistance forces. In most certification procedures, including the WLTP recently adopted by the EU, the latter is achieved mainly through coast down tests. Subsequently, the resistance values measured are used for setting up the chassis-dyno resistances applied during the laboratory measurements. These reference values are obtained under controlled conditions, while a series of corrections are applied to make the test procedure more repeatable and reproducible. In real driving, the reference road loads are influenced by a series of factors leading to a divergence between the certified fuel consumption values, and the real-world ones. An approach of calculating representative road loads during on-road tests can help to obtain a clearer view of vehicle efficiency and quickly validate the officially declared road loads. This approach is crucial also for validating simulations and achieving better estimates of the actual fuel consumption, a requirement introduced by the new policy adopted in the EU. In this direction, a series of on-road experiments were conducted,…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Hardware-in-the-Loop and Public Road Testing of RLVW and GLOSA Connected Vehicle Applications

Camp LLC-Jayendra Parikh
Ford Motor Co., Ltd.-Alexander Katriniok
  • Technical Paper
  • 2020-01-1379
To be published on 2020-04-14 by SAE International in United States
Each year, large number of traffic accidents with a large number of injuries and fatalities occur. To reduce these accidents, automotive companies have been developing newer and better active and passive safety measures to increase the safety of passengers. With the developments in connected vehicle infrastructure on the roads and on-board-units for Vehicle to Everything (V2X) connectivity in newer vehicles, V2X communication offers possibilities for preventing accidents as V2X equipped vehicles have situational awareness of other vehicles and road users around them through Vehicle to Vehicle (V2V) and Vehicle to Pedestrian (V2P) communication, and signal phase and timing and map information on signalized intersections through Vehicle to Infrastructure (V2I) communication. Therefore, vehicle on-board computers can calculate an optimal speed profile for fuel economy purposes or prevent crashes related to red light violations. This paper addresses these two main advantages, firstly by developing and using Hardware-in-the-Loop (HIL) simulator testing and experimental vehicle testing environments of an algorithm for preventing red light violation, called Red Light Violation Warning (RLVW). The HIL simulator used in the testing is…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental Evaluation of Longitudinal Control for Connected and Automated Vehicles through Vehicle-in-the-Loop Testing

Argonne National Laboratory-Miriam Di Russo, Simeon Iliev, Kevin M. Stutenberg, Eric Rask
Wayne State University-Jerry Ku
  • Technical Paper
  • 2020-01-0714
To be published on 2020-04-14 by SAE International in United States
Automated driving functionalities delivered through Advanced Driver Assistance System (ADAS) have been adopted more and more frequently in consumer vehicles. The development and implementation of such functionalities pose new challenges in safety and functional testing and the associated validations, due primarily to their high demands on facility and infrastructure. This paper presents a rather unique Vehicle-in-the-Loop (VIL) test setup and methodology compared those previously reported, by combining the advantages of the hardware-in-the-loop (HIL) and traditional chassis dynamometer test cell in place of on-road testing, with a multi-agent real-time simulator for the rest of test environment. Details associated with applying the proposed VIL for testing adaptive cruise control (ACC), in conjunction with approaches for creating a virtual lead vehicle, as well as results of energy consumption analysis for a 2017 Toyota Prime with stock and improved longitudinal control algorithm, are reported to illustrate the effectiveness of low-infrastructure-demand test setup and the potential in applying the setup and methodology to other ADAS functionalities
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Perceptions of Two Unique Lane Centering Systems: An FOT Interview Analysis

Massachusetts Institute of Technology-Steven Landry, Bobbie Seppelt, Luca Russo, Bruce Mehler, Pnina Gershon, Bryan Reimer
Touchstone Evaluations Inc-Linda Angell
  • Technical Paper
  • 2020-01-0108
To be published on 2020-04-14 by SAE International in United States
Objective: The goal of this interview analysis was to explore and document the perceptions of participants in a field operational test (FOT) including two unique lane centering systems (S90’s Pilot Assist, and CT6’s Super Cruise). Both systems offer similar functionality on paper (continuous longitudinal and lateral vehicle control), but have drastically different HMI implementations. Methods: Twenty-four drivers (16 male, 8 female) in the Greater-Boston Area participated in an FOT study, in which each participant drove one of two vehicles for a month. Upon vehicle return, drivers took part in a 30 to 60-minute semi-structured interview to record their perceptions of the vehicle’s various ADAS systems. Transcripts of the interviews were coded by two researchers to assign each participant’s statements to specific vehicle technologies as well as to attribute perceptions to each statement. The analyses in this paper focus on adaptive cruise control (ACC) and lane centering technologies. Results: Participants cite perceived positive benefits, such as increased safety and comfort provided by lane centering and adaptive cruise control systems, but also cite concern over the possibility…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Autonomous Lane Change Control Using Proportional-Integral-Derivative Controller And Bicycle Model

Kettering University-Ajinkya A. Joshi, Diane L. Peters, Jennifer M. Bastiaan
  • Technical Paper
  • 2020-01-0215
To be published on 2020-04-14 by SAE International in United States
As advanced vehicle controls and autonomy become mainstream in the automotive industry, the need to employ traditional mathematical models and control strategies arises for the purpose of simulating autonomous vehicle handling maneuvers. This study focuses on lane change maneuvers for autonomous vehicles driving at low speeds. The lane change methodology uses a PID (Proportional-Integral-Derivative) controller to command the steering wheel angle, based on the yaw motion and lateral displacement of the vehicle. The controller was developed and tested on a bicycle model of an electric vehicle (a Chevrolet Bolt 2017), with the implementation done in MATLAB/Simulink. This simple mathematical model was chosen in order to limit computational demands, while still being capable of simulating a smooth lane change maneuver under the direction of the car’s mission planning module at modest levels of lateral acceleration. The simulation indicated that the lane change control system performed well for low speeds and at moderate steering wheel angles. After the simulation phase, the model was converted to implementable vehicle code and integrated into a vehicle for on-road testing of…