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Traditional IC engine powered vehicles readily mask the lower amplitude transients like hiss, clicks and slight tones. However, due to the popularity and expected increase in number of hybrid and electrically driven automobiles all around the world, all the OEMs are concerned about the vehicle interior quietness and sound quality. Refrigerant system induced hiss/gurgle is quite normal phenomenon but its excessive levels and frequent occurrences can be objectionable to demanding customers. Introduction of new environmentally friendly refrigerants (HFO-1234yf), A/C compressors with built-in oil separation (reduced damping in evaporator), and use of IHX with coupled suction and liquid lines, may lead to increased refrigerant system induced hiss and gurgle. Operation of typical A/C system generates steady-state and transient noises that consist of audible tones and high frequency hiss.

As vehicle emission regulations become increasingly rigorous, the automotive industry is accelerating the development of electrified vehicle platforms such as Battery Electric Vehicles (BEV) and Plug-in Hybrid Electric Vehicles (PHEV). Since the available waste heat from these vehicles is limited, additional heat sources such as electric heaters are needed for cabin heating operation. The use of a heat pump system is one of the solutions to improve EV driving range at cold ambient conditions. In this study, an efficient gas-injection heat pump system has been developed, which achieves high cabin heating performance at low ambient temperature and dehumidification operation without the assistance of electric heaters in ’17 model year Prius Prime.

In this work, Dedicated Short Range Communication (DSRC) capabilities combined with classical autonomous vehicles’ on-board sensors (Camera) are used to trigger a Comfortable Emergency Brake (CEB) for urban traffic light intersection scenario. The system is designed to achieve CEB in two phases, the Automated Comfortable Brake (ACB) and the full stop Automated Emergency Brake (AEB). The ACB is triggered first based on the content of the Signal Phase and Timing (SPaT) / Map data (MAP) messages received from the Road Side Unit (RSU) at larger distances. And, once the traffic light becomes in the detection field of view of the camera, the output of the Camera-based Traffic Light Detection (TLD) and recognition software is fused with the SPaT/MAP content to decide on triggering the full stop AEB. In the automated vehicle, the current traffic light color and duration received in the SPaT message is parsed; and compared with the TLD output for color matching.

Robust lane marking detection remains a challenge, particularly in temperate climates where markings degrade rapidly due to winter conditions and snow removal efforts. In previous work, dynamic Bayesian networks with heuristic features were used with the feature distributions trained using semi-supervised expectation maximization, which greatly reduced sensitivity to initialization. This work has been extended in three important respects. First, the tracking formulation used in previous work has been corrected to prevent false positives in situations where only poor RANSAC hypotheses were generated. Second, the null hypothesis is reformulated to guarantee that detected hypotheses satisfy a minimum likelihood. Third, the computational requirements have been greatly reduced by computing an upper bound on the marginal likelihood of all part hypotheses upon generation and rejecting parts with an upper bound less likely than the null hypothesis.

With the advent of EVs/HEVs and implementation of Idle-Stop-Start (ISS) technologies on internal combustion engine (ICE) driven cars/trucks to improve fuel economy and reduce pollution, refrigerant sub-system (RSS) induced noise phenomena like, hissing, gurgling and tones become readily audible and can result in customer complaints and concerns. One of the key components that induce these noise phenomena is the Thermostatic Expansion Valve (TXV). The TXV throttles compressed liquid refrigerant through the evaporator that results in air-conditioning (A/C) or thermal system comfort for occupants and dehumidification for safety, when needed. Under certain operating conditions, the flow of gas and/or liquid/gas refrigerant at high pressure and velocity excites audible acoustical and structural modes inherent in the tubing/evaporator/HVAC case. These modes may often get masked and sometimes enhanced by the engine harmonics and blower noise.

Tightening global emissions standards are driving automotive Original Equipment Manufacturer’s (OEM’s) to utilize Three Way Catalyst (TWC) aftertreatment systems that can perform with greater efficiency and greater measured control of Precious Group Metals (PGM) use. At the same time, TWC aftertreatment systems minimize exhaust system pressure drops. This study will determine the influence of catalyst substrate cell geometry on emission and PGM usage. Additionally, a study of lightoff and backpressure comparisons will be conducted. The two substrate configurations used are hex/750cpsi and square/750cpsi.

Electrification has been considered one of the major solutions to meet stringent U.S. fuel economy and CO2 targets of 2025. Numerous published researches are mainly focused on improving fuel economy for passenger cars, but less has been done for larger size light-duty vehicles, such as pickup trucks, SUVs and minivans, which contribute to a considerable amount of vehicle sales in the U.S. market. Due to larger vehicle size and different usage profile, it is expected that the ideal electrification architecture is different than that of a passenger car. The purpose of this study is to identify potential low-voltage electrification solutions for an existing class 2 pickup truck for fuel economy improvement, while taking into account cost effectiveness for large market penetration. One of the potential solutions is presented. In this paper, vehicle electrification configuration concepts are examined by computer simulations.

The popularity of new Human-Machine-Interfaces (HMIs) comes with growing concerns for driver distraction. In part, this concern stems from a rising challenge to design systems that can make functions accessible to drivers while maintaining drivers’ ability to cope with the complex driving task. Therefore, engineers need assessment methods which can evaluate how well a user interface achieves the dual-goal of making secondary tasks accessible, while allowing safe driving. Most prior methods have emphasized measuring off-road glances during HMI use. An alternative to this is to consider both on-road and off-road glances, as done in Kircher and Ahlstrom’s AttenD algorithm [1]. In this study, we compared two types of prevalent visual-manual user interfaces based on AttenD. The two HMIs of interest were a touchscreen-based interface (already in production) and a remote-rotary-controller-based interface (a high-fidelity prototype).

Mcity at the University of Michigan in Ann Arbor provides a realistic off-roadway environment in which to test vehicles and drivers in complex traffic situations. It is intended for testing of various levels of vehicle automation, from advanced driver assistance systems (ADAS) to fully self-driving vehicles. In a recent human factors study of interfaces for teen drivers, we performed parallel experiments in a driving simulator and Mcity. We implemented driving scenarios of moderate complexity (e.g., passing a vehicle parked on the right side of the road just before a pedestrian crosswalk, with the parked vehicle partially blocking the view of the crosswalk) in both the simulator and at Mcity.

In this paper, a method of improving the automated vehicle’s perception using a multi-pose camera system (MPCS) is presented. The proposed MPCS is composed of two identical colored and high frame-rate cameras: one installed in the driver side and the other in the passenger side. Perspective of MPCS varies depending on the width of vehicle type in which MPCS is installed. To increase perspective, we use the maximum width of the host vehicle as camera to camera distance for the MPCS. In addition, angular positions of the two cameras in MPCS are controlled by two separate electric motor-based actuators. Steering wheel angle, which is available from the vehicle Controller Area Network (CAN) messages, is used to supply information to the actuators to synchronize MPCS camera positions with the host vehicle steering wheel.

Wireless power transfer (WPT) technology has started to be applied in charging electrical vehicles (EV). EV models with built-in wireless charging capability is expected to be available from several major automakers in the next few years. Meanwhile, problems associated with the massive adoption of automobiles require new format of vehicles, especially the form with compact size and electric power. An inductively charged autonomous bicycle (iCab) is proposed, which has both the automotive driving and wireless charging features. It is designed to be compatible with an EV wireless charger. The wireless charging interoperability issue of the single transmitting coil capable to charge both the EV and iCab is studied in this paper. The receiving coil of a wireless charger is usually designed to match with single transmitting coil and to have a fixed power level output.

Due to the recent trend emphasizing on environmental friendly, engine supercharger downsizing technology has been under development globally. In this report, the technical knowledge for high performance and high quality water-cooled CAC development is provided. For higher cooling performance, the optimum fin and tube core matrix water-cooled CAC, delivering best performance and quality have been developed. For higher reliability against thermal stress, the detail specifications of water-cooled CAC based on the transient analysis and the simulation technology have been established.

DENSO International America, Inc. and the University of Iowa-Operator Performance Laboratory (OPL) have developed a series of new Multi-Modal Interface for Drivers (MMID) in order to improve driver safety, comfort, convenience and connectivity.

Vehicle lighting has become more demanding with different load requirements, strict Electromagnetic Compatibility (EMC) requirements, accuracy requirements, and power consumption requirements. These requirements are all under the constraint of ever shrinking PCB’s driving up the cost of PCB real estate. Pulse width modulation (PWM) is used to control the interior and exterior lighting in vehicles and meet all these requirements. One or more electronic control units in the body domain of a vehicle contain a number of integrated circuits that drive loads using PWM signals. In addition to driving loads, PWM signals are used for things such as dimming and diagnostic functions. In current technology the PWM signal is usually composed of a trapezoidal wave or rounded wave which control bulbs and light emitting diodes (LED) loads in a vehicle.

The ejector is a fluid pump that recovers expansion energy, which is wasted in the conventional refrigeration cycle decompression process, and converts the recovered expansion energy into pressure energy. In the ejector cycle, the ejector helps to reduce power consumption of the compressor by using the above mentioned pressure-rising effect. Consequently, the ejector system can improve energy efficiency of the refrigeration cycle. In previous work, the ejector cycle was used to reduce power consumption in refrigeration cycles for a cool-box (a beverage cooling inside the vehicle) and refrigerated truck box. Both of these applications used the ejector to achieve refrigerant pressure/temperature below the vehicle cabin temperature. Now, the ejector has been integrated into the vehicle cabin evaporator to reduce power consumption of the refrigeration cycle for vehicle cabin cooling.

Audible tones in vehicle interiors are undesirable because of their impact on customer satisfaction and quality metrics. Most of the loudest tonal noise sources located in the engine compartment are isolated from the vehicle interior by the dash-wall. A majority of the automotive blower/s are located in the vehicle interior in the close proximity of the driver and passengers. Hence, the blower induced tones (if present) become audible and airborne, they readily propagate to the vehicle occupants. The severity of these audible tones is going to be most annoying in future especially in vehicles equipped with hybrid, electric and start/stop at idle technologies, for improved fuel economy mandates in future. Due to increased demands for quieter vehicle interiors with higher airflow for achieving quick thermal comfort, the HVAC systems are designed with lower pressure drop which helps reduced low frequency broad-band noise but does not mask the BPF tone and its harmonics.

Externally-connected Electronic Control Units (ECUs) contain millions of lines of code, which may contain security vulnerabilities. Hackers may exploit these vulnerabilities to gain code execution privileges, which affect public safety. Traditional Cybersecurity solutions fall short in meeting automotive ECU constraints such as zero false positives, intermittent connectivity, and low performance impact. A desirable solution would be deterministic, require minimum resources, and protect against known and unknown security threats. We integrated Autonomous Security on a BeagleBone Black (BBB) system to evaluate the feasibility of mitigating Cybersecurity risks against potential threats. We identified key metrics that should be measured, such as level of security, ease of integration and system performance impact. In this paper, we describe the integration and evaluation process and present its results.

New sensing and fast processing technologies will create an electronic driver in every car by 2025. All people in the vehicle will be passengers! The vehicle will drive by itself from A to B. In this case what will be need for HUD? Below is an investigation of the key issues and some possible solutions.

With the increasing stringency of emission regulations, auto makers are now improving vehicle fuel efficiency via all kinds of technologies, such as hybrid systems, turbocharged or supercharged engines, engine auto start/stop, active grille shutters, etc. By implementing a variety of technologies, the engine cooling module’s working environment and work load has changed. This paper will mainly focus on the impact to the thermal durability of the engine cooling module’s main radiator from active grille shutter and electric thermostat implementation. A 2017MY hybrid vehicle using the above technology is evaluated by a wind tunnel test at a variety of ambient temperatures and driving conditions. First, such technologies’ control logic is studied by the wind tunnel test, so that the evaluation condition for evaluating the radiator’s thermal stress can be properly chosen to represent the actual field usage.

The goal of this project was to investigate how to make driver distraction state classification more efficient by applying selected machine learning techniques to existing datasets. The data set used in this project included both overt driver behavior measures (e.g., lane keeping and headway measures) and indices of internal cognitive processes (e.g., driver situation awareness responses) collected under four distraction conditions, including no-distraction, visual-manual distraction only, cognitive distraction only, and dual distraction conditions. The baseline classification method that we employed was a support vector machine (SVM) to first identify driver states of visual-manual distraction and then to identify any cognitive-related distraction among the visual-manual distraction cases and other non-visual manual distraction cases.