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Racing Green Endurance: An EV Record will focus on what a small team of ambitious and talented engineers can do when they have a dream! Back in 2009, a team of graduates from Imperial College London came together to do something radical to change the public perception of electric vehicles forever. They came up with the idea to design and build the world's longest range electric car, and then drive it down the longest and toughest road in the world; the 26,000km Pan-American Highway! Racing Green Endurance: An EV Record will share the story from start to finish, and will also focus on the technology used to achieve such a feat, with particular mention of the electric motors. Presenter Alexander Schey, Imperial College London

The copper-rotor induction-motor made its debut in automotive electric traction in 1990 in GM's Impact EV. Since then, this motor architecture has covered millions of miles on other vehicle platforms which will soon include Toyota's RAV4-EV. With the industry's attention focused on cost-effective alternatives to permanent-magnet traction motors, the induction motor has returned to the spotlight. This talk will overview where the copper-rotor induction-motor is today, how the technology has evolved since the days of the GM Impact, the state-of-play in its mass-manufacturing processes and today's major supply-chain players. Presenter Malcolm Burwell, International Copper Association Inc.

The traction motor is key to the �synergy of the electric powertrain�, the overall functionality of the battery, e-motor, power control electronics, and charging system. Therefore some automakers have decided to design, develop, and produce their traction motors in house while some others are working with suppliers for their electric power train motors. Off-the-shelf motors, no matter how extensively they are adapted for a specific application, can compromise the efficiencies of the propulsion system. Presenter Marc Winterhoff, Roland Berger Strategy Consultants

The CAN protocol has served the automotive and related industries well for over twenty-five (25) years now; with the original CAN protocol officially released in 1986 followed by the release of CAN 2.0 in 1991. Since then many variants and improvements in CAN combined with the proliferation of automotive onboard microprocessor based sensors and controllers have resulted in CAN establishing itself as the dominant network architecture for automotive onboard communication in layers one (1) and two (2). Going forward however, the almost exponential growth of automotive onboard computing and the associated devices necessary for supporting said growth will unfortunately necessitate an equivalent growth in the already crowded wired physical infrastructure unless a suitable wireless alternative can be provided. While a wireless implementation of CAN has been produced, it has never obtained real traction within the automotive world.

Abstract Investigation of vehicle resistant forces and power losses is of crucial importance owing to current state of energy consumption in transport sector. Meanwhile, considerable portion of resistant forces in a ground vehicle is traced back to tires. Pneumatic tires are known to be a source of energy dissipation as a consequence of their viscoelastic nature. The current study aims to provide a modification to tire resistance by considering the power loss in a tire due to longitudinal slip. The modified tire resistance is comprised of rolling resistance and a newly introduced resistance caused by tire slip, called slip resistance. The physical model is chosen for parameters sensitivity study since the tractive force is described in this model via tangible physical parameters, e.g. tire tangential stiffness, coefficient of friction, and contact patch length.

Abstract The non-pneumatic tire (NPT) has been widely used due to its advantages of no run-flat, no need for air maintenance, low rolling resistance, and improvement of passenger comfort due to its better shock absorption. It has a variety of applications in military vehicles, earthmovers, the lunar rover, stair-climbing vehicles, etc. Recently, the Unique Puncture-Proof Tire System (UPTIS) NPT has been introduced for passenger vehicles. In this study, three different design configurations, viz., Tweel, Honeycomb, and newly developed UPTIS, have been compared. The effect of polyurethane (PU) material nonlinearity has also been introduced by applying five different nonlinear PU material properties in the spokes. The combined analysis of the PU material nonlinearity and spoke design configuration on the overall tire stiffness and spoke damage prediction is done using three-dimensional (3D) finite element modelling (FEM) simulations performed in ANSYS 16.0.

Abstract In this article performance of the innovative Crank-Lever Electromagnetic Damper (CLEMD) for an off-road vehicle suspension system is analyzed. To determine the characteristic behavior of the CLEMD, the damping force it provides on the suspension system is varied by changing the values of the damping coefficient in the simulations. Various parameters considered in the analyses include power regenerated, voltage, current, comfort, road-holding, etc. The behavior of all the parameters of the CLEMD is observed for an off-road vehicle by carrying out simulations on country roads since the off-road vehicles are subjected to higher road irregularities and hence provide an opportunity to regenerate a higher amount of power. A two-dimensional (2-D) model of a vehicle developed in SimMechanics is interfaced with a Simulink model of CLEMDs for the analyses.

Abstract This article applies a new method for the evaluation and estimation of real-life energy consumption of two different thermal management systems based on driving behavior in the course of the day. Recent attempts to find energy-efficient thermal management systems for electric and plug-in hybrid electric vehicles have led to using secondary loop systems as an alternative approach for meeting dynamic heating and cooling demands and reducing refrigerant charge. However, the additional layer of thermal resistance, which influences the system’s transient behavior as well as passenger compartment comfort during cool-down or heat-up, makes it difficult to estimate the annual energy consumption. In this article, the overall energy consumption of a conventional and a secondary loop system is compared using a new method for describing actual customers’ driving behavior in the course of the day.

Abstract The dynamic characteristics of tires are critical in the overall vibrations of vehicles because the tire-road interface is the only medium of energy transfer between the vehicle and the road surface. Obtaining the natural frequencies and mode shapes of the tire helps in improving the comfort of the passengers. The vibrational characteristics of structures are usually obtained by performing conventional impact hammer modal testing, in which the structure is excited with an impact hammer and the response of the structure under excitation is captured using accelerometers. However, this approach only provides the response of the structure at a few discrete locations, and it is challenging to use this procedure for rotating structures. Digital Image Correlation (DIC) helps in overcoming these challenges by providing the full-field response of the structure.

Abstract Future SAE Level 4 and Level 5 autonomous vehicles (AV) will require novel applications of localization, perception, control, and artificial intelligence technology in order to offer innovative and disruptive solutions to current mobility problems. This article concentrates on low-speed autonomous shuttles that are transitioning from being tested in limited traffic, dedicated routes to being deployed as SAE Level 4 automated driving vehicles in urban environments like college campuses and outdoor shopping centers within smart cities. The Ohio State University has designated a small segment in an underserved area of the campus as an initial AV pilot test route for the deployment of low-speed autonomous shuttles. This article presents initial results of ongoing work on developing solutions to the localization and perception challenges of this planned pilot deployment.

Abstract The ability of senior citizens as well as other members of the general population to engage in an effective manner with technology is of increasing importance as new and innovative technologies become available. While recognizing the challenges that technologies can have on different populations, the ability to interact successfully with new technologies will, for seniors, have important consequences that can affect their quality of life and those of their families in numerous and important ways. This study, building upon previous research, examines the major dimensions of decision-making regarding attitudes toward autonomous vehicle technologies (ATVs) and their use. The study utilized data from a study of senior citizens in the Dallas-Fort Worth (DFW) area and compared the results with a sample of graduate students from a local university.

How can car designers evaluate device’s position inside a car today? Today only subjective tests or “reachability” tests are made to assess if a generic user is able to reach devices, but it’s no longer enough. The aim of this study is to identify an instrument (index) that is able to provide a numerical information about the discomfort level connected with a posture that is kept inside a car to reach a device, by this instrument it should be possible not only judge a posture, but also compare different solutions and get rapid and accurate evaluations. In the state of the art there are many indexes developed to evaluate postural comfort (like RULA, REBA and LUBA [3, 4, 5]) but none of them has been realized to evaluate postures’ conditions that can be detected inside a car, so their evaluations cannot be acceptable.

This paper focuses on full body dynamical analysis of car ingress/egress motion. It aims at proposing an experimental protocol adapted for analysing joint loads using inverse dynamics. Two preliminary studies were first performed in order to 1/ define the main driver/car interactions so as to allow measuring the contact forces at all possible contact zones and 2/ identify the design parameters that mainly influence the discomfort. In order to verify the feasibility of the protocol, a laboratory study was carried out, during which two subjects tested two car configurations. The experimental equipment was composed of a variable car mock-up, an optoelectronic motion tracking system, two 6D-force plates installed on the ground next to the doorframe and on the car floor, a 6D-Force sensor between the steering wheel and the steering column, and two pressure maps on the seat. Motions were reconstructed from measured surface markers trajectories using inverse kinematics.

In 2006, there were approximately 23,500 rear-end crashes involving heavy trucks (i.e., gross vehicle weight greater than 4,536 kg). The Enhanced Rear Signaling (ERS) for Heavy Trucks project was developed by the Federal Motor Carrier Safety Administration (FMCSA) to investigate methods to reduce or mitigate those crashes where a heavy truck has been struck from behind by another vehicle. Visual warnings have been shown to be effective, assuming the following driver is looking directly at the warning display or has his/her eyes drawn to it. A visual warning can be placed where it is needed and it can be designed so that its meaning is nearly unambiguous. FMCSA contracted with the Virginia Tech Transportation Institute (VTTI) to investigate potential benefit of additional rear warning-light configurations as rear-end crash countermeasures for heavy trucks.

The recent interest in IntelliDrive(SM) and vehicle connectivity has gone past previous notions of automatic collision notification, internet browsing and off board navigation. Now, in addition to applying the 5.9 GHz ITS band for cooperative collision avoidance, other applications using connectivity between the vehicle and signalized intersections have emerged. Contemporary applications enhancing fuel economy and reducing green house gases (GHG) are the subject of current research and development. Cooperation between vehicle electronics and intelligent traffic management systems could change the landscape for addressing future ECO (economical and ecological) requirements. This manuscript will outline development within one automotive supplier targeted at using connectivity as an enabling technology for sustaining the vision of smart and green transportation systems.

A truck-trailer combination is modeled using ADAMS/Car from MSC Software for handling and ride comfort performance simulations. The handling events include a double lane change and lateral roll stability. The ride comfort performance events include several sized half-rounds and various RMS courses. The variables for handling performance evaluation include lateral acceleration, roll angles and tire patch normal loads. The variables for ride performance evaluation are absorbed power and peak acceleration. This study considers the trailer spring stiffness, anti-roll bar and jounce bumper gap as the design variables. Through DOE simulations, we derived the response surface models of various performance variables so that we could consider the performance sensitivities to the design variables.

A comprehensive research is presented aiming at assessing the ride comfort of subjects seated into road or off-road vehicles. Although many papers and books have appeared in the literature, many issues on ride comfort are still to be understood, in particular, the paper investigates the mutual effects of the posture and the vibration caused mostly from road unevenness. The paper is divided into two parts. In the first part, a mathematical model of a seated subject is validated by means of actual measurements on human subjects riding on a car. Such measurements refer to the accelerations acting at the subject/seat interface (vertical acceleration at the seat cushion and horizontal acceleration at the seat back). A proper dummy is used to derive the seat stiffness and damping.

The advancements made in modeling and parameter identification of nonlinear isolation components in the underlying investigation confirm the importance of accurate Multibody Dynamics modeling of these components for reducing vibration and/or improving ride comfort. Considering dynamic stiffness and loss angle characteristics, the proposed nonlinear isolation component uses the Bouc/Wen hysteresis model for excitation amplitude dependency and a transfer function for excitation frequency dependency. Various combinations of Bouc/Wen hysteresis parameters result in different shapes for hysteresis loops and allows for modeling a wide range of soft and stiff isolator characteristics. The effect of the proposed isolation component on ride studies is illustrated by simulating a maneuver on a road profile using the OpenCRG road description with SimXpert Motion Workspace and Adams/Car. Tire belt dynamics are captured by adding a rigid ring part to the PAC2002 tire model [ 1 ].

Virtual simulation of passenger compartment climatic conditions is becoming increasingly important as a complement to the wind tunnel and field testing to achieve improved thermal comfort while reducing the vehicle development time and cost. The vehicle cabin is subjected to various thermal environments. At the same time many of the design parameters are dependent on each other and the relationship among them is quite complex. Therefore, an experimental parametric study is very time consuming. The present 3-D RadTherm analysis coupled with the 3-D CFD flow field analysis takes into account the geometrical configuration of the passenger compartment which includes glazing surfaces and pertinent physical and thermal properties of the enclosure with particular emphasis on the glass properties. Virtual Thermal Comfort Engineering (VTCE) is a process that takes into account the cabin thermal environment coupled with a human physiology model.

Seat cooling systems are becoming more common as luxury features offered by original equipment manufacturers. Despite the extensive research & application of these systems, a thermal model and comfort requirements of the occupant/seat system have not been established. Without a model or thermal criteria for comfort, the seat temperature & humidity conditions required for optimal comfort can not be defined. A synopsis of the thermal comfort conditions required to achieve an occupant's subjective comfort as well as their comfort transition points are explained. In this context a model is designed specifically from a heat and mass transfer perspective between an occupant and a seat cooling system. Focus is given to the local conduction, convection, and evaporative cooling that takes place at the body to seat surface interface.