Your Selections

Comfort
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.

Effects of a Probability-Based Green Light Optimized Speed Advisory on Dilemma Zone Exposure

Indiana Department of Transportation-James Sturdevant
Purdue University-Enrique Saldivar-Carranza, Howell Li, Woosung Kim, Jijo Mathew, Darcy Bullock
  • Technical Paper
  • 2020-01-0116
To be published on 2020-04-14 by SAE International in United States
Green Light Optimized Speed Advisory (GLOSA) systems have the objective of providing a recommended speed to arrive at a traffic signal during the green phase of the cycle. GLOSA has been shown to decrease travel time, fuel consumption, and carbon emissions; simultaneously, it has been demonstrated to increase driver and passenger comfort. Few studies have been conducted using historical cycle-by-cycle phase probabilities to assess the performance of a speed advisory capable of recommending a speed for various traffic signal operating modes (fixed-time, semi-actuated, and fully-actuated). In this study, a GLOSA system based on phase probability is proposed. The probability is calculated prior to each trip from a previous week’s, same time-of-day (TOD) and day-of-week (DOW) period, traffic signal controller high-resolution event data. By utilizing this advisory method, real-time communications from the vehicle to infrastructure (V2I) become unnecessary, eliminating data-loss related issues. The effects of three different advice approaches (conservative, balanced, and aggressive) on dilemma zone exposure are analyzed. Proof of concept is carried out by virtually driving through a test-route composed of an arterial that…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A dynamic trajectory planning for automatic vehicles based on improved discrete optimization method

Chongqing University-Pengyun Zeng, Zheng Ling
  • Technical Paper
  • 2020-01-0120
To be published on 2020-04-14 by SAE International in United States
The dynamic trajectory planning problem for automatic vehicles in complex traffic scenarios is investigated in this paper. A hierarchical motion planning framework is developed to complete the complex planning task. An improved dangerous potential field in the curvilinear coordinate system is constructed to describe the collision risk of automatic vehicles accurately instead of the discrete Gaussian convolution algorithm. At the same time, the driving comfort is also considered in order to generate an optimal, smooth, collision-free and feasible path in dynamics. The optimal path can be mapped into the Cartesian coordinate system simply and conveniently. Furthermore, a velocity profile considering practical vehicle dynamics is also presented to improve the safety and the comfort in driving. The effectiveness of the proposed dynamic trajectory planning is verified by numerical simulation for several typical traffic scenarios.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Multi-zone HAVC Development and Validation with Integrated Heated/Vented Seat Control

FCA US LLC-Murad Maghaireh, Michael Hoppe
  • Technical Paper
  • 2020-01-1247
To be published on 2020-04-14 by SAE International in United States
Vehicle multi zone automatic Heating , Venting and Air Conditioning (HVAC) is the advanced form of the traditional air conditioning, the advantage of multi zone automatic HVAC is that it allows the passengers of a vehicle to set a desired temperature for their own zone within the vehicle compartment. This desired temperature is then maintained by the HVAC system, which determines how best to control the available environment data that leads to a higher comfort for the passengers. To achieve ultimate thermal comfort of the occupants in a vehicle, multi zone HVAC takes things a step further by adding heated, vented seats and, steering wheel to the HVAC controller hardware as well as strategies. The heating and cooling of the occupants by this more advance one integrated system is performed by complex control algorithms in form of embedded software programs and private LIN network. This paper describes the approach and tools used to develop, simulate and validate the one integrated climate control system. Included are 1- introduction of an integrated HVAC , steering wheel and…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Decision Making and Trajectory Planning of Intelligent Vehicle’ s Lane-changing Behavior on Highways under Multi-objective Constrains

Wuhan University of Technology-Linzhen Nie, Zhishuai Yin, Haoran Huang
  • Technical Paper
  • 2020-01-0124
To be published on 2020-04-14 by SAE International in United States
Discretionary lane-changing is commonly seen in highway driving. Intelligent vehicles are expected to change lanes discretionarily for better driving experience and higher traffic efficiency. This study proposes to optimize the decision making and trajectory planning process so that intelligent vehicles make lane changes not only with driving safety taken into account, but also with the goal to improve driving comfort as well as to meet the driver’ s expectation. The mechanism of how various factors contribute to the driver’s intention to change lanes is studied by carrying out a series of driving simulation experiments, and a Lane-changing Intention Generation (LIG) model based on Convolutional Neural Network (CNN) is proposed. The inputs of the CNN are data fragments of several influence factors including the relative speed and the distance between the subject vehicle and the preceding vehicles in current lane and both sides of the lane, and the type of the preceding vehicles in current lane and both sides of the lane, the average speed of the left and right traffic flow, the in a certain…
   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.

In-situ studies on the effect of solar control glazings on in-cabin thermal environment for hot and humid climatic zones

Saint Gobain India Pvt., Ltd.-Jyothi Latha Tamalapakula
  • Technical Paper
  • 2020-01-1257
To be published on 2020-04-14 by SAE International in United States
Thermal comfort in a passenger cabin is the basic necessity of an occupant especially in hot and humid climatic conditions. It is known that the reflective glazing solutions provide better thermal comfort inside the cabin due to significant reflection of IR part of solar radiation. However, in hot and humid climatic zones like India, significant reduction in heat load can also be achieved through cost effective solar control absorbing glazings. Thus, the present work aims to study the effect of solar control absorbing glazings on cabin inside temperatures and its impact on thermal comfort of the occupants in tropical climates. A combination of glazing sets with a range of solar energy transmission and absorption values are considered for the study. Indoor soak and cool tests are performed on a sedan model with multiple sets of solar control absorbing glass combinations. A constant ambient temperature of 38˚C and solar radiation of 1000W/m2 are maintained throughout the tests. Wind speed was simulated for a vehicle running speed of 45kmph. Net heat gain inside the cabin as a…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Searching for Optimal Solutions for Motor Performance Design

Honda R&D Co.,Ltd.-Yuko Miyabe, Masahito Kakema, Toshihiro Saito
  • Technical Paper
  • 2020-01-0460
To be published on 2020-04-14 by SAE International in United States
Because strength and the torque/rotational speed characteristic play a considerable role in determining the maximum speed and the acceleration force of a vehicle, they have been taken up as optimization issues. By contrast, loss and torque ripple have not necessarily been focused on in the initial search for optimal solutions. They are both linked to efficiency, comfortability, and the cost of development of the cooling system and supporting structures, however, it is necessary to reduce both parameters. For this reason, it is important to search for the Pareto front for strength, the torque/rotational speed characteristic, loss, and torque ripple at the initial stage of design. The strength constraint was set that von Mises stress in the rotor core in relation to the centrifugal force load at maximum speed would not exceed the breaking strength of a standard electromagnetic steel sheet material. The torque/rotational speed characteristic employed the maximum torque for each rotational speed when maximum torque per ampere control and field weakening control are applied, with consideration of maximum input voltage and current. Maximum torque…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of an Air support system for long-distance drive comfort

Hyundai Motor Company-Dongwoo Jeong, Seon Chae Na, Sangdo Park, Sangho Kim, Seungyoung Lee
Hyundai Transys-Inho Lee, Sunghoon Kim
  • Technical Paper
  • 2020-01-0868
To be published on 2020-04-14 by SAE International in United States
Passenger fatigue during long distance driving is greatly influenced by the comfort performance of the seat and is one of the important performance of the seat. In order to satisfy this performance, it is determined by the appropriate contour of the seat and the appropriate pad with sufficient thickness and the frame supporting the pad and coverings. Recently, however, more parts such as ventilation seats and passenger detection sensors have taken up the pad In addition, The height of the vehicle have been lowered to enhance car styling, and battery for electric vehicle applied to the underbody of the vehicle, reducing the package space of seats in the vehicle. These external factors eventually lead to a reduced pad thickness of the seat cushion and exacerbate the most important cushioning in the seat cushion compartments, creating an uncomfortable cushioning problem when driving long distances. To improve the cushion composition of the seat within a limited package, air bladders are applied to the underside of the cushion pad. In addition, the function to support the buttocks using…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Influence of Background Spectral Distribution on Perceptions of Discomfort Glare

Rensselaer Polytechnic Institute-Rohan M. Nagare, John D. Bullough
  • Technical Paper
  • 2020-01-0637
To be published on 2020-04-14 by SAE International in United States
The advent of light-emitting diode (LED) technology for automotive lighting allows flexibility of the spectral distribution of forward headlighting systems, while meeting current requirements for "white" illumination. As vehicle headlights have become whiter (with more short-wavelength light output) over the past several decades, their potential impacts on visual discomfort for oncoming and preceding drivers have been hotly debated. It is known that a greater proportion of short-wavelength energy increases discomfort glare, and that increasing the background light level (e.g., through roadway lighting) will decrease perceptions of discomfort. More recently it has been demonstrated that the visual system exhibits enhanced short-wavelength sensitivity for perceptions of scene brightness. As a result, roads illuminated by light sources with higher correlated color temperatures (CCTs) will be judged as appearing to be brighter than those illuminated to the same light level by sources with lower CCTs. The present laboratory study was conducted to identify whether the increased scene brightness of a road illuminated with greater short-wavelength light helps to mitigate discomfort glare more than the same scene illuminated to the…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Robust Design Optimization of Electronic Shifting Mechanism Considering Manipulation Comfort

Nanjing University of Science & Technology-Jipeng Xie, Guolai Yang, Quanzhao Sun, Jianli Ge, Xinghao Huang
  • Technical Paper
  • 2020-01-0605
To be published on 2020-04-14 by SAE International in United States
Electronic shifter is an important human-machine interaction device in modern vehicles. To reduce the influence of shifting mechanism and structural parameters on control comfort, in the early stage of product quality design, we proposed a grey relation grade dynamic robustness method. In this paper, based on the multi-body dynamic model of gear shifting mechanism that was verified by experiments, the dynamic shifting force can be calculated by the parameterized multi-body dynamic model, and used as dynamic response variables. Then we stablished the linear relationship between response variables and signal factors, and measured the correlation degree between response variables and signal factors by the grey relation grade analysis. And choose the groove structure’s parameters, the contact parameters, the compression spring’s stiffness and preload as controllable factors. The influence of each controllable factors on the response signals determined by the variance analysis, and get the order of controllable factors ,then taking the controllable factors with significant effects as the optimal combination when the variance of the response variable is the minimum, finally obtained the robustness parameters of…