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In order to speed up engine coolant warm-up, the exhaust heat recirculation system collects and reuses the heat from exhaust gases by utilizing the heat exchanger. The conventional system improves actual fuel economy at the scene of the engine restart in winter season only. The heat recirculation system becomes more effective at the low outside temperature because it takes longer time to warm up engine coolant. However, the heat recirculation system becomes less effective at the high outside temperature because it takes shorter time to warm up engine coolant. Therefore, the new exhaust heat recirculation system is developed, which adopted as follows: 1) a fin-type heat exchanger in order to enhance exhaust recirculation efficiency 2) a thinner heat exchanger component and smaller amount of engine coolant capacity in the heat exchanger in order to reduce the heat mass As a result, the actual fuel economy is more improved in winter season.

The use of smart portable devices in vehicles creates the possibility to record useful data and helps develop a better understanding of driving behavior. In the past few years the UTDrive mobile App (a.k.a MobileUTDrive) has been developed with the goal of improving driver/passenger safety, while simultaneously maintaining the ability to establish monitoring techniques that can be used on mobile devices on various vehicles. In this study, we extend the ability of MobileUTDrive to understand the impact on driver performance on public roads in the presence of distraction from speech/voice based tasks versus tactile/hands-on tasks. Drivers are asked to interact with the device in both voice-based and hands-on modalities and their reaction time and comfort level are logged. To evaluate the driving patterns while handling the device by speech/hand, the signals from device inertial sensors are retrieved and used to construct Gaussian Mixture Models (GMM).

This paper describes the Common Automobile Program (CAP) that can be implemented to improve mass transportation. CAP is the use of automated electric vehicles using smart navigation and control technologies to improve mass transportation. In CAP, common vehicles are used by different passengers, thus, reducing the on-road traffic and also the parking space required. Various low-cost stations are to be built along specified paths and the vehicle can be used at the convenience of the commuter. Currently, buses and trains require the passengers to wait at the station and a significant amount of time is spent at intermediate stops. The vehicle in CAP runs directly from origin to destination and also eliminates the waiting time at stations. Passengers do not wait for vehicles; instead vehicles wait for the passengers. The journey starts as the passenger enters the station and selects the destination.

This paper reports an effort to improve plan of vehicle trajectory using an approach with rapidly-exploring random trees (RRT), which has been widely adopted in the prior art for complex and dynamic traffic environment. Design and implement of an integrated threat assessment is presented that evaluates threats of the trajectory. A node and trajectory evaluation index was introduced into the proposed RRT algorithm to connect an appropriate node and select the best trajectory. The contribution of this paper is on the threat assessment that takes into account not only obstacle avoidance but also stability. The simulation is conducted and the results show that the proposed method works as expected and is valid and effective.

Current vehicles, especially the electric ones, are complex mechatronic devices. The pickup vehicles of small sizes are currently used in transport considerably. They often operate within a repeating scheme of a limited variety of tracks and larger fleets. Thanks to mechatronic design of vehicles and their components and availability of high capacity data connection with computational centers (clouds), there are many means to optimize their performance, both by planning prior the trip and recalculations during the route. Although many aspects of this opportunity were already addressed, the paper shows an approach developed to further increase the range of e-vehicle operation. It is based on prior information about the route profile, traffic density, road conditions, past behaviour, mathematical models of the route, vehicle and dynamic optimization. The most important part of the procedure is performed in the cloud, using both computational power and rich information resources.

In order to cope with new regulations and find a better compromise between fuel consumption, pollutant emissions and comfort, thermal management technologies are getting more complex. This is especially true when it requires replacing a basic passive solution with a mechatronic system. A new Active Cooling Thermal-management (ACT) valve concept has been developed to specifically replace wax thermostat while keeping the same packaging and cost range and bringing closed loop temperature control, fast response time and precision. This new module is manufactured by assembling injected thermoplastic components. By essence it leads to dimension tolerances, deformation and wear over its life. Those uncertainties and deviations have to be taken into account when the nominal part is designed to ensure part efficiency till the end of its life.

Ever tightening emission limits and constant pressure for increasing engine power are resulting in increased engine operating temperature. This coupled with continuous drive for fuel economy improvement because of the stiff competition are forcing OEMs to explore alternative cooling solutions resulting in less power take off and quick response as cooling requirement shoots up. Aim of this paper is to analyze the relative benefits of incorporating a new cooling fan drive system concept over conventional viscous fan driven cooling system with step-less variable speed control independent of engine speed variation. Hydraulic fan drive system control fan rpm based on the fluid temperature as compared to air temperature in viscous coupling fan drive system. HFD system provides quick response when increase in coolant temperature is observed. HFD system in this way provide more control on fan rpm.

Automotive engineering processes are dynamic, iterative and driven by changes. Reasons for changes on development artifacts are manifold, but the result is a new evolution step which may influence all, some, or just a single development artifact. Consequently, research on impact analysis put forth approaches to assess the adverse effects of changes. However, understanding and implementing functional changes and its consequences in the safety domain is often aggravated by dependencies between different types of development artifacts, scattered in various (tool) formats. Safety properties may change depending on the type of a modification. Thereby, connected analyses like fault trees, Failure Modes and Effects Analysis (FMEA), and safety concepts cannot be reused easily if the artifacts on which they are based on are affected by changes. In this paper we suggest a new difference analysis approach which allows a (semi-)automated comparison of safety work products based on models.

In order to reduce the energy consumption of the automotive air conditioning system, adsorption heat pump (AHP) system is one of the key technologies. We have been developing compact AHP system utilizing the exhaust heat from the engine coolant system (80-100 °C), which can meet the requirements in the automotive application. However, AHP systems have not been practically used in automotive applications because of its low volumetric power density of the adsorber. The volumetric power density of the adsorber is proportional to sorption rate, packing density and latent heat. In general, the sorption rate is determined by mass transfer resistance in primary particle of an adsorbent and heat and mass transfer resistance in packed bed. In order to improve the volumetric power density of the adsorber, it is necessary to increase the production of the sorption rate and the packing density.

The Runtime Verification ECU (RV-ECU) is a new development platform for checking and enforcing the safety of automotive bus communications and software systems. RV-ECU uses runtime verification, a formal analysis subfield geared at validating and verifying systems as they run, to ensure that all manufacturer and third-party safety specifications are complied with during the operation of the vehicle. By compiling formal safety properties into code using a certifying compiler, the RV-ECU executes only provably correct code that checks for safety violations as the system runs. RV-ECU can also recover from violations of these properties, either by itself in simple cases or together with safe message-sending libraries implementable on third-party control units on the bus. RV-ECU can be updated with new specifications after a vehicle is released, enhancing the safety of vehicles that have already been sold and deployed.

This paper presents the design and implementation of a new steering control method for lane following control (LFC) using a camera. With the road information provided by the image sensor, the LFC system calculates the steering command based on the Target and Control (T&C) driver steering model. The T&C driver model employs a look-ahead control structure to capture the drivers’ core steering mechanism. Based on the models of the steering actuator and the vehicle dynamics, optimal control gains can be determined for any given look-ahead distance (normalized by the vehicle speed). With these simple gains, the vehicle can track very well along the center of the lane. This LFC system was first simulated under the Model-in-the-Loop (MiL) test using the CarSim simulation. The simulations show that the resultant lateral offsets are smaller than those from typical driver models.

A key component of developing a safety-critical automotive system in compliance with ISO 26262 is developing what is known as the safety case. This delivery justifies that the system is free from unreasonable risk and that the safety requirements are complete and satisfied according to evidence from ISO 26262 work products. However, the standard provides neither practical guidance on how the safety case should be developed, nor how the safety argument should be evaluated in the functional safety assessment process. This paper discusses quality and product readiness of the system under development in the context of safety case generation. We will focus on the software level and ISO 26262-6 requirements that relate to this. We will look at the software lifecycle of the system and how to measure and deliver key data throughout this lifecycle.

Automotive manufacturers and their suppliers increasingly need to follow the objectives of ISO 26262 as it is now state-of-the art and as it is the case that an ever increasing number of active and passive safety systems are developed within cars. This has increased the need to define a safe system development process. This paper proposes a model-based approach including automatic and certified code generation to efficiently implement the embedded software that controls these systems while meeting the needed safety requirements and obeying the rules of ISO 26262.

For many crucial applications, establishing important properties of Simulink models by testing is either extremely resource intensive or impossible, and proof of the properties is highly desirable. Many Simulink models rely upon discrete-valued functions for which the function values are defined as a lookup table of correspondences between values in the domain and range, with linear interpolation used to evaluate intermediate values in the domain. Such discrete-valued functions arise in applications for which no known closed-form algebraic definition exists. In general, the proof of a property for a model that includes a discrete-valued function has to be by case analysis. For a single function and with mechanical support, case analysis is manageable. However, for models that include multiple discrete-valued functions, the number of cases can be the product of the cardinalities of the domains of the individual functions.

This technical paper aims to provide a framework for simulating the thermal behavior of an automotive electrical connector with the current flow across each terminal. An automotive electrical connector uses multiple terminals fitted in the respective cavity of a connector. Temperature at terminal increases with the current flow level across it. This temperature rise occurs due to resistive heat loss in the terminal. Due to this, temperature in the surrounding cavities also rises; hence, the current carrying capacity of those cavities reduces. Analysis of similar scenarios for design alternatives and design decisions is important to develop reliable and optimized solutions. The reliable and optimized solution helps to save the cost. There is a large variation of different terminals used in the wiring harness, and there are various parameters attributing to this variation (shape, size, material, plating etc…).

High-end vehicles with latest technology and autonomous driving experience have to bear the cost of increasing number of sensors on-board. It would be beneficial to reduce some of the sensors in the vehicle and make use of other available resources, retaining the same functionality. This paper discusses a novel technique of estimating the weight of seat occupant from an already existing DC motor without using additional pressure sensors. Passenger weight information is important for seat-belt reminder system as well as supplemental restraint system that will decide the air-bag deployment. The mathematical model for a series-type DC motor is analyzed and simulated using MATLAB. Further, results of the experiment performed on a lower capacity motor are shared and compared with the simulation results. Formulating a linear relation gives a possibility to develop a device for occupant weight measurement inside the high-end vehicles.

Increasingly, Ethernet is being used in automotive as a vehicle network backbone. It is ideal for service-oriented communications; streamed communications, such as Audio/Video Bridging (AVB) [1]; and Diagnostics over Internet Protocol (DoIP) [2] communications - areas in which high-bandwidth and reliable performance are essential. Designers are accustomed to network communication systems CAN, LIN, and FlexRay, but how will the timing performance be verified in an Ethernet network? This paper looks at network-wide timing analysis challenges where a mixture of CAN, FlexRay, and Ethernetbased busses co-exist. It is also worth noting that the AUTOSAR standard [3] supports timing definition for all elements in a mixed topology network, but again, accounting for the many different timing paths is a non-trivial process. Figure 1 The Ethernet backbone serving different domains.

The concept of camless engines enables us to optimize the overall engine efficiency and performance, as it provides great flexibility in valve timing and valve displacement. This paper deals with design of camless engines with pneumatic actuator. The main objective is to build a prototype and test its performance at different engine speeds. Also an extensive research on the sensors is done to detect the various sensors that could be used to identify the crankshaft position. Here the features and advantages over conventional engines are discussed. In addition the overview of the camless system in the engine is focused along with the design principle and the components used. The system thus designed is capable of actuating at 1500 rpm and demonstrates the ability of pneumatic actuators to be used in an internal combustion engine with low rpm needs.

Lane change events can be a source of traffic accidents; drivers can make improper lane changes for many reasons. In this paper we present a comprehensive study of a passive method of predicting lane changes based on three physiological signals: electrocardiogram (ECG), respiration signals, and galvanic skin response (GSR). Specifically, we discuss methods for feature selection, feature reduction, classification, and post processing techniques for reliable lane change prediction. Data were recorded for on-road driving for several drivers. Results show that the average accuracy of a single driver test was approx. 70%. It was greater than the accuracy for each cross-driver test. Also, prediction for younger drivers was better.

Mitsubishi Electric has been developing a lane keeping assist system (LKAS). This system consists of our products such as an electric power steering (EPS), a camera, and an electronic control unit (ECU) for ADAS. In this system, the camera detects a lane marker, the ECU estimates reference path and vehicle position, and calculates reference steering wheel angle, and the EPS controls a steering wheel angle based on reference steering wheel angle. In this paper, we explain the calculation method of reference steering wheel angle for path tracking control. We derive a formula of reference steering wheel angle calculation that converges lateral position deviation in desired time by using lateral position deviation change rate control on forward gaze point as path tracking control algorithm. Since the formula is obtained from the vehicle model, we can easily design a controller depending on the vehicle type, by using known vehicle specifications.