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Today open source software is widely used in different domains like Desktop systems, Consumer electronics (smart phones, TV, washing machines, camera, printers, smart watches), Automotive, Automation etc. With the increased involvement of the open source software in the different domains including the safety critical ones, there has been a requirement of the well-defined test strategy to test and verify such systems. Currently there are multiple open source tools and frameworks to choose from. The paper describes the various open source test strategies and tools available to qualify such systems, their features, maintenance, community support, advantages and disadvantages. Target audience would be the software engineers, program managers, using an open source stack for the product development.

Electronics components are estimated to be between 9 to 15 % of a total vehicle cost, and this trend will remain strong for the next years. The amount of electronics content in a vehicle has grown steadily since 1970's, and as a result, development challenges such as testing and validation are a key aspect of its overall development costs. Testing costs can amount easily to US$ 500 k in medium complex automotive parts of a vehicle (e.g. instrument cluster) depending on a specific OEM customer demand, and this on top of limited regional laboratory capacity can also lead to increased testing time. The goal of this paper is to outline key aspects of electronics in vehicle components testing, including overall costs and timing, and propose a lean approach to optimize such costs & timing. The key aspects of such optimization include not only resources, but also laboratories and upfront OEM customer planning.

Estimation and prediction of residual life and reliability are serious concerns in life cycle management for aging structures. Laboratory testing replicating fatigue loading for a typical military aircraft wing skin was undertaken. Specimens were tested until their fatigue life expended reached 100% of the component fatigue life. Then, scanning electron microscopy was used to quantify the size and location of fatigue cracks within the high stress regions of simulated fastener holes. Distributions for crack size, nearest neighbor distances, and spatial location were characterized statistically in order to estimate residual life and to provide input for life cycle management. Insights into crack initiation and growth are also provided.

To obtain the maximum output power and fuel economy from an internal combustion engine, it is often necessary to detect engine knock and operate the engine at its knock limit. This paper presents the ability to detect knock using in-cylinder ionization signals on a large displacement, air-cooled, “V” twin motorcycle engine over the engine operational map. The knock detection ability of three different sensors is compared: production knock (accelerometer) sensor, in-cylinder pressure sensor, and ionization sensor. The test data shows that the ionization sensor is able to detect knock better than the production knock sensor when there is high mechanical noise present in the engine.

With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

In this paper, an analytical procedure for prediction of shell radiated noise of air induction systems (AIS) due to engine acoustic excitation, without a prototype and physical measurement, is presented. A set of modeling and simulation techniques are introduced to address the challenges to the analytical radiated noise prediction of AIS products. A filter seal model is developed to simulate the unique nonlinear stiffness and damping properties of air cleaner boxes. A finite element model (FEM) of the AIS assembly is established by incorporating the AIS structure, the proposed filter seal model and its acoustic cavity model. The coupled acoustic-structural FEM of the AIS assembly is then employed to compute the velocity frequency response of the AIS structure with respect to the air-borne acoustic excitations.

This paper describes a front road wheel steer-by-wire system with two actuator motors on the rack and pinion assembly to move the road wheels. Dual actuators are used to provide actuator redundancy and to enhance the fault tolerance capability. When one actuator faults or fails, the other actuator is designed to work independently and maintain full system performance. The paper emphasizes control method to implement the motion control for the front road wheel steer-by-wire system with two actuators on the common load. The proposed dual servo synchronization motion control implements the angle tracking for the road wheel reference input by controlling two actuators synchronously and cooperatively. It includes two servo feedback control loops to track the common reference input. The angular position error between two feedback loops is compensated using a synchronized compensator.

Most new passenger vehicles on the road today are equipped with a disposable OEM engine intake filter made of cellulose paper or synthetic non-woven media. Engine intake filters have an expected and recommended service life (by OEMs) of approximately 45K to 75K kilometers under normal driving conditions [ref. 2, 3, 4 & 5]. Majority of air filter element manufacturers do not recommend any type of cleaning to be performed on their OEM products. However, cleaning OEM and aftermarket air filters is common for end-customers in areas such as Asia, Middle East and South America. Vehicle owners in some regions would like to service and clean their own air filter elements in an effort to reduce vehicle operating costs. As a result, a number of OEMs selling passenger vehicles in these regions are requesting their suppliers explore solutions and the effects of whether cleaning air filter elements is appropriate for proper engine operation.

Steer-by-wire systems (SBW) offer the potential to enhance steering functionality by enabling features such as automatic lane keeping, park assist, variable steer ratio, and advanced vehicle dynamics control. The lack of a steering intermediate shaft significantly enhances vehicle architectural flexibility. These potential benefits led GM to include steer-by-wire technology in its next generation fuel cell demonstration vehicle, called “Sequel.” The Sequel's steer-by-wire system consists of front and rear electromechanical actuators, a torque feedback emulator for the steering wheel, and a distributed electronic control system. Redundancy of sensors, actuators, controllers, and power allows the system to be fault-tolerant. Control is provided by multiple ECU's that are linked by a fault-tolerant communication system called FlexRay. In this paper, we describe the objectives for fault tolerance and performance that were established for the Sequel.

An algorithm, which determines the range of a preceding vehicle by a single image, had been proposed. It uses a “Range-Window Algorithm”. Here in order to realize higher robustness and stability, the pattern matching is incorporated into the algorithm. A single camera system using this algorithm has an advantage over the high cost of stereo cameras, millimeter wave radar and non-robust mechanical scanning in some laser radars. And it also provides lateral position of the vehicle. The algorithm uses several portions of a captured image, namely windows. Each window is corresponding to a predetermined range and has the fixed physical width and height. In each window, the size and position of objects in the image are estimated through the ratio between the widths of the objects and the window, and a score is given to each object. The object having the highest score is determined as the best object. The range of the window corresponding to the best object becomes an estimated range.

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain.

A test load specification is required to validate an automotive product to meet the durability and design life requirements. Traditionally in the automotive industry, load specifications for design validation tests are directly given by OEMs, which are generally developed from an envelop of generic customer usage profiles and are, in most cases, over-specified. In recent years, however, there are many occasions that a proposed load specification for a particular product is requested. The particular test load specification for a particular product is generated based on the measured load data at its mounting location on the given type of vehicles, which contains more realistic time domain load levels and associated frequency contents. The measured time domain load is then processed to frequency domain test load data by using the fast Fourier transform and damage equivalent techniques.

A hydraulic steering pump system will be considered in this report. The objective is to improve the design of a specific power steering pump using computational fluid dynamics (CFD) tools. The first part of this report deals with a pump oil seal leak. The thermal and fluid environments have been simulated. A variable fluid viscosity is used, showing a 15-20% increase in peak temperature. Potential improvements in product design have been suggested. The second part deals with using computer tools to reduce redundant testing. This includes use of parametric approach towards optimization. A rotating grid approach (basic moving mesh technique) is used.

Modern automobiles utilize stabilizer bars to increase vehicle roll stiffness. Stabilizer bars are laterally mounted torsional springs which resist vertical displacement of the wheels relative to one another. A stabilizer bar is constructed in such a way that it will meet package constraints and fatigue requirements. In order to design a robust stabilizer bar, Taguchi's “Design of Experiment method” is used. The objective of this paper is to develop a robust stabilizer bar design that will maximize the fatigue life and the roll stiffness while minimizing weight. This study is based on results obtained by CAE analysis.

Plastic air induction system (AIS) has been widely used in vehicle powertrain applications for reduced weight, cost, and improved engine performance. Physical design validation (DV) tests of an AIS, as to meet durability and reliability requirements, are usually conducted by employing the frequency domain vibration tests, either sine sweep or random vibration excitations, with a temperature cycling range typically from -40°C to 120°C. It is well known that under high vibration loading and large temperature range, the plastic components of the AIS demonstrate much higher nonlinear response behaviors as compared with metal products. In order to implement a virtual test for plastic AIS products, a practical procedure to model a nonlinear system and to simulate the frequency response of the system, is crucial. The challenge is to model the plastic AIS assembly as a function of loads and temperatures, and to evaluate the dynamic response and fatigue life in frequency domain as well.

Evaporators for automotive air-conditioning systems are being coated externally to improve corrosion resistance, water drainage, and reduce potential odor concerns. The coating durability and efficiency in achieving its corrosion resistance depends on the coating uniformity and adhesion characteristics. Good coating adhesion on aluminum surface can be achieved after freeing the surface from the oxide and flux residues. Evaporators manufactured by the Controlled Atmosphere Brazing (CAB) process have flux residue remaining on the surface, the presence of which interferes with the coating process and also affects the performance of coated components. A methodology to quantify the effect of high Nocolok flux residue on heat exchanger coating uniformity has been presented.

Welding is one of the most commonly used fabrication method in various automotive applications. Welding is a metallurgical fusion process in which parts or work pieces to be joined are heated above their melting temperature and then solidified. Some of the effects of the welding include residual stresses and Heat Affected Zone (HAZ). A methodology is proposed to study the welding process using the commercial finite element software, ABAQUS. Non linear transient heat transfer analysis is used. Effects of heat energy input rate and heat input time on residual stresses and HAZ are determined.

Not all software tools are created equal and not all software tools are created to perform the same tasks. Therefore, different software tools are used to perform different tasks. However, being able to share the information between the different software tools, without having to manually re-enter (duplicate) any of the information, can save a lot of time and improve the quality of the product. The control software interface presented in this paper, allows system engineers to exchange data between software tools in an efficient manner which maximizes each tools capabilities and ultimately reduces development time and improves the quality of the product.

The work presented here outlines the development of a robust CAO tool for optimal design of electromagnetic retarder machines. The developed EM-CAO tool is then used to perform a wide variety of CAE/CAO tasks, from automatically computing the torque versus rpm performance curves of the EM retarder to performing optimization. Two specific examples of optimal design of the EM retarder are reported. Through the use of a task manager/optimizer repetitive jobs are fully automated thereby making the analysis and optimization of electromagnetic retarders faster and user-friendlier.

Manual ‘porting” of source code is often required in order to “reuse” control software in different applications with different target hardware. This process is not cost effective. Maintaining multiple “versions” of the same software also causes problems. This paper describes a way in which multiple target source code can be generated from a single model. A custom data class is developed so that it can be used to define both signal and parameter data types necessary for data dictionary-driven models. This capability allows a single model to be used to generate code for multiple target hardware architectures. A software development process using a generic model to support multiple hardware targets is compared with the hand porting process (e.g. floating-point to/from fixed-point). Auto code generation from a sample multi-target feature model will be presented. The efficiency of the auto code will also be discussed.