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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.

One of the many critical design criteria for vehicle harness design is circuit protection. This process typically involves calculating the maximum load on each wire manually and then comparing the result to a spreadsheet that may be quite old. Testing physical prototypes occurs so late in the design process that problems found can be very expensive to rectify. Using simulation to detect faults, such as short circuits or the time for the fuse to blow vs. the time for the wire to smoke is an effective solution that can not only save a great deal in costs, but shorten the development cycle as well.

Distracted driving remains a serious risk to motorists in the US and worldwide. Over 3,000 people were killed in 2013 in the US because of distracted driving; and over 420,000 people were injured. A system that can accurately detect distracted driving would potentially be able to alert drivers, bringing their attention back to the primary driving task and potentially saving lives. This paper documents an effort to develop an algorithm that can detect visual distraction using vehicle-based sensor signals such as steering wheel inputs and lane position. Additionally, the vehicle-based algorithm is compared with a version that includes driving-based signals in the form of head tracking data. The algorithms were developed using machine learning techniques and combine a Random Forest model for instantaneous detection with a Hidden Markov model for time series predictions.

Automotive vehicles today consist of very complex network of electronic control units (ECU) connected with each other using different network implementations such as Controller Area Network (CAN), FlexRay, etc. There are several ECUs inside a vehicle targeting specific applications such as engine, transmission, body, steering, brakes, infotainment/navigation, etc. comprising on an average more than 50 ECUs executing more than 50 million lines of software code. It is expected to increase exponentially in the next few years. Such complex electric/electronic (E/E) architecture and software calls for a comprehensive, flexible and systematic development and validation environment especially for a system level or vehicle level development. To achieve this goal, we have built a virtual multi-ECU high fidelity cyber-physical multi-rate cosimulation that closely resembles a realistic hardware based automotive embedded system.

Bearings are a major component in any rotating system. With continually increasing speeds, bearing failure modes take new unconventional forms that often are not understood. In high speed applications, rolling element forces and gyroscopic moments can be significantly high compared to the applied forces acting on a bearing. Such moments create a “driving” torque causing outer race to creep. In this paper a mathematical model for the dynamics of a rolling element in a high speed bearing is derived. Preload values counterbalancing the torque driving the outer race to rotate can be predicted from this model. An attempt to experimentally measure this torque using a specially designed apparatus with integrated strain gauge torque sensor is also described. Both model and experimental measurements are aimed at understanding, and therefore preventing bearing failures due to outer race (creep) rotations.

Micro hybrid Systems are emerging as a promising solution to reduce the fuel consumption and greenhouse gas emissions in emerging markets, where the strict emission requirements are being enforced gradually. Micro hybrid Systems reduce the fuel consumption and greenhouse gas emissions in a conventional vehicle with 12 V electrical system, by optimizing the electrical energy generation, storage, and distribution, with functions like Intelligent Alternator Control, Engine Stop/Start, and Load Management. With the advent of Connected Car Systems, information about the vehicle is seamlessly provided to the customer not just through the Human Machine Interface systems within the vehicle, but to other mobile devices used by the customers.

The paper discusses the development and implementation of a form of in-vehicle communications for the body control in an Ariel Atom niche sports car. A Local Interconnect Network (LIN) bus has been developed that runs the LIN signals over the power lines of the vehicle wiring harness. The LIN system has one master and up to 15 slave ECUs. LIN is normally run at a maximum bit rate of 20 Kbit/s, however this system has been implemented at 57.6 Kbit/s by modulating over the power lines. Benefits of this approach include weight reduction, reduction in the number wires, ease in retro-fitting to existing vehicle architectures as only requires a connection to power lines and the ability to monitor the signals via the battery pins of the OBD connector of the vehicle. The approach has resulted in a reduction in weight due to wiring and electronic control unit reduction.

A steady increasing share and complexity of automotive software is a huge challenge for quality management during software development and in-use phases. In cases of faults occurring in customer’s use, warranty leads to product recalls which are typically associated with high costs. To avoid software faults efficiently, quality management and enhanced development processes have to be realized by the introduction of specific analysis methods and Key Process/Performance Indicators (KPIs) to enable objective quality evaluations as soon as possible during product development process. The paper introduces an application of specific analysis methods by using KPIs and discusses their potential for automotive software quality improvement. Target is to support quality evaluation and risk-analysis for the release process of automotive software.

In this paper, consideration is made to create a simulation model of the BCI test method, which is one of the EMC evaluation methods for in-vehicle electronic devices, and an intrinsic model of a BCI probe is provided. Using this model, it is demonstrated that when the impedance of the BCI probe is sufficiently high, the BCI probe serves as a transformer with a winding ratio of 1:1, and the admittance of a line or a load connected to each wire becomes proportional to the magnitude of current flowing in each wire. This model can also be applied when the leakage inductance inside the BCI probe is taken into consideration. The validity of this model is verified by experiment using a jig which can clamp multiple wires. In addition, by using this model, it is demonstrated that the S-parameters for dozens of wires clamped in the BCI probe can be generated using the S-parameter measurement results from when one wire is in the BCI probe.