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Software-in-the-Loop (SiL) test environments are the ideal virtual platforms for enabling continuous-development, -integration, -testing -delivery or -deployment commonly referred as Continuous-X (CX) of the complex functionalities in the current automotive industry. This trend especially is contributed by several factors such as the industry wide standardization of the model exchange formats, interfaces as well as architecture definitions. The approach of frontloading software testing with SiL test environments is predominantly advocated as well as already adopted by various Automotive OEMs, thereby the demand for innovating applicable methods is increasing. However, prominent usage of the existing monolithic architecture for interaction of various elements in the SiL environment, without regarding the separation between functional and non-functional test scope, is reducing the usability and thus limiting significantly the cost saving potential of CX with SiL.

Acoustics and vibrations are amongst the foremost indicators in perceiving the quality of drive units. Analyzing these factors is vital for improve the performances of electro-mechanical systems. This paper deals with the study of vibro-acoustic behavior concerning the drivetrain components using system modeling and Finite Element calculations. A generic simulation methodology within system modeling is proposed enabling the vibro-acoustic simulation of electro-mechanical drivetrains. Excitations for these systems mostly arise from the electric motor and mechanical gears. The paper initially depicts the system model for gear whining considering the associated nonlinearities of the mesh. The results obtained from the gear mesh submodel, together with the excitations resulting from the motor, aid in the comprehension of the forces at the bearings and of the vibrations at the housings.

Safety-critical embedded software has to satisfy stringent quality requirements. One such requirement, imposed by all contemporary safety standards, is that no critical run-time errors must occur. Runtime errors can be caused by undefined or unspecified behavior of the programming language; examples are buffer overflows or data races. They may cause erroneous or erratic behavior, induce system failures, and constitute security vulnerabilities. A sound static analyzer reports all such defects in the code, or proves their absence. Sound static program analysis is a verification technique recommended by ISO/FDIS 26262 for software unit verification and for the verification of software integration. In this article we propose an analysis methodology that has been implemented with the static analyzer Astrée. It supports quick turn-around times and gives highly precise whole-program results.

Future emission norms in India (BS6) necessitates the 2 wheeler industry to work towards emission optimization measures. Engine operation at stoichiometric Air-Fuel Ratio (AFR) would result in a good performance, durability and least emissions. To keep the AFR close to stoichiometric condition, an Oxygen sensor is placed in the exhaust system, which detects if air-fuel mixture is rich (λ<1) or lean (λ>1) and provides feedback to fuel injection system for suitable fuel control. O2 sensor has a ceramic element, which needs to be heated to a working temperature for its functioning. The ceramic element would break (thermal shock) if water in liquid form comes in contact with it when the element is hot.

The fuel spray behavior in the near nozzle region of a gasoline injector is challenging to predict due to existing pressure gradients and turbulences of the internal flow and in-nozzle cavitation. Therefore, statistical parameters for spray characterization through experiments must be considered. The characterization of spray velocity fields in the near-nozzle region is of particular importance as the velocity information is crucial in understanding the hydrodynamic processes which take place further downstream during fuel atomization and mixture formation. This knowledge is needed in order to optimize injector nozzles for future requirements. In this study, the results of three experimental approaches for determination of spray velocity in the near-nozzle region are presented. Two different injector nozzle types were measured through high-speed shadowgraph imaging, Laser Doppler Anemometry (LDA) and X-ray imaging.

As automobiles become increasingly smarter, the need to understand within the automotive software the physical behavior of its parts is growing as well. The laws of physics governing such behavior are mostly formulated as differential equations, which today are usually created or obtained from various modeling tools. For solving them, the tools offer several solvers to satisfy the requirements of different problems. E.g. simple and fast explicit low order solvers for non-stiff problems and more complex implicit solvers for stiff problems. Though the modeling and code generation features as available in such tools are desirable for embedded automotive software, they cannot be used directly due to special restrictions with respect to hard realtime constraints. One such restriction is the organization of automotive software in components complying with the AUTOSAR standard which is not widely supported by the modeling tools.

The Side View Assist is the World’s first rider assistance system for two-wheelers. This is a Blind Spot Warning system, which uses four ultrasonic sensors to monitor the surrounding of the rider. Whenever there is a vehicle (i.e. a car, truck, or another motorbike) in the rider’s blind spot, the technology warns the rider with an optical signal close to the mirror. This will allow the rider to avoid a collision when changing lanes. In the current vehicle application, Side View Assist is active at speeds ranging from 25 to 80 kilometers per hour and supports riders whenever the difference in relative speed to other road users is small. The system helps to improve safety especially in cities, where heavy traffic makes it necessary to change lanes more often. Originally such systems have been developed for cars and different system solutions for cars have been in serial production for several years. The challenge was to adapt these systems so they would work for two-wheelers as well.

Many software functions currently available in the engine control units have been developed for several years (decades in some cases), reengineered or adapted due to new requirements, what may add to their inherent complexity an unnecessary complication. This paper deals with the study and implementation of a software reengineering strategy for the embedded domain, which is in transfer from research department to product development, here applied to improve maintainability of flex fuel functions. The strategy uses the SCODE “Essential Analysis”, an approach for the embedded system domain. The method allows to reduce the system complexity to the unavoidable inherent problem complexity, by decomposing the system into smaller sub problems based on its essential physics. A case study was carried out to redesign a function of fuel adaptation. The analysis was performed with the support of a tool, which covers all the phases of the method.

To satisfy future emission classes, e.g. EU6c, the particulate number (PN) of Direct-Injection Spark-Ignition (DISI) engines must be reduced. For these engines, different components influence the combustion process and thus also the formation of soot particles and deposits. Along with other engine components, the injector nozzle influences the particulate number and deposits in both fuel spray behavior and nozzle “tip wetting”. In case of non-optimized nozzle layouts, fuel may impinge on the piston and the liner in an unfavorable way, which implies low-oxygen diffusive combustion by retarded vaporizing wall films. For the tip wetting, wall films are present on the actual surface of the nozzle tip, which is also caused by unadapted nozzles. For non-optimized nozzles, the latter effect can become quite dominant. This paper deals with systematic nozzle development activities towards low-deposit nozzle tips and thus decreasing PN values.

CNG direct injection is a promising technology to promote the acceptance of natural gas engines. Among the beneficial properties of CNG, like reduced pollutants and CO2 emissions, the direct injection contributes to a higher volumetric efficiency and thus to a better driveability, one of the most limiting drawbacks of today’s CNG vehicles. But such a combustion concept increases the demands on the injection system and mixture formation. Among other things it requires a much higher flow rate at low injection pressure. This can be only provided by an outward-opening nozzle due to its large cross-section. Nevertheless its hollow cone jet with a specific propagation behavior leads to an adverse fuel-air distribution especially at higher loads under scavenging conditions. This paper covers numerical and experimental analysis of CNG direct injection to understand its mixture formation.

Cost reduction of engine management systems (EMS) for two-wheeler applications is the key to utilize their potentials compared to carburetor bikes regarding emissions, fuel economy and system robustness. In order to reduce the costs of a system with port fuel injection (PFI) Bosch is developing an EMS without a manifold air pressure (MAP) sensor. The pressure sensor is usually used to compensate for different influences on the air mass, which cannot be detected via the throttle position sensor (TPS) and mean engine speed. Such influences are different leakage rates of the throttle body and changing ambient conditions like air pressure. Bosch has shown in the past that a virtual sensor relying on model based evaluation of engine speed can be used for a detection of leakage air mass in idling to improve the pre-control of the air-fuel ratio. This provides a functionality which so far was only possible with an intake pressure sensor.

Current exhaust gas emission regulations can only be well adhered to through optimal interplay of combustion engine and exhaust gas after-treatment systems. Combining a modern diesel engine with several exhaust gas after-treatment components (DPF, catalytic converters) leads to extremely complex drive systems, with very complex and technically demanding control systems. Current engine ECUs (Electronic Control Unit) have hundreds of functions with thousands of parameters that can be adapted to keep the exhaust gas emissions within the given limits. Each of these functions has to be calibrated and tested in accordance with the rest of the ECU software. To date this task has been performed mostly on engine test benches or in Hardware-in-the-Loop (HiL) setups. In this paper, a Software-in-the-Loop (SiL) approach, consisting of an engine model and an exhaust gas treatment (EGT) model, coupled with software from a real diesel engine ECU, will be described in detail.

Regarding the strongly growing two-wheeler market fuel economy, price and emission legislations are in focus of current development work. Fuel economy as well as emissions can be improved by introduction of engine management systems (EMS). In order to provide the benefits of an EMS for low cost motorcycles, efforts are being made at BOSCH to reduce the costs of a port fuel injection (PFI) system. The present paper describes a method of how to reduce the number of sensors of a PFI system by the use of sophisticated software functions based on high-resolution engine speed evaluation. In order to improve the performance of a system working without a MAP-sensor (manifold air pressure sensor) an air charge feature (ACFn) based on engine speed is introduced. It is shown by an experiment that ACFn allows to detect and adapt changes in manifold air pressure. Cross-influences on ACFn are analyzed by simulations and engine test bench measurements.

In order to fulfil emission legislation and achieve good drivability of combustion-engine-powered vehicles, information about the air charge and feedback about the engine condition is necessary. In current systems, different sensors are used, e.g. the MAP (manifold air pressure) sensor and a lambda sensor. Aiming at reducing costs, efforts are being made to reduce the number of sensors while still retrieving the necessary information. Various engine speed based functions are state-of-the-art for automotive engines, e.g. for fuel-calibration, misfire-detection etc. Those functions evaluate the engine speed fluctuations during a working cycle induced by combustion. For multiple-cylinder engines, those influences are overlapping, therefore evaluation possibilities are limited. The work presented is based on the effect that at a single-cylinder engine, there is no overlap of combustion influences of various cylinders on the crankshaft.

Among the currently available sensor interfaces for automotive applications, only the PSI5 interface - as standardized in the new 2001 PSI5 V2.0 - meets the rising system requirements, the increased requirements of the new environmental regulations, and the requirements of current functional safety standards. PSI5 not only features the capability to transmit highly accurate sensor data, high EMC robustness, bus capability, and bidirectional communication, but also offers savings in the cable harness and a reduced number of connector pins by using just two wires. It therefore offers enhanced technical functionality at a reasonable cost. To improve the environmental friendliness and sustainable operation of drive concepts, Bosch is also employing sophisticated and cross-linked sensors, actuators and control units. In addition, there is also the need to optimize system functions, weight, construction space and costs.

AUTOSAR (AUTomotive Open System ARchitecture) is a worldwide standard for automotive basic software in line with an architecture that eases exchange and transfer of application software components between platforms or companies. AUTOSAR provides the standardized architecture together with the specifications of the basics software along with the methodology for developing embedded control units for automotive applications. AUTOSAR matured over the last several years through intensive development, implementation and maintenance. Two main releases (R3.2 and R4.0) represent its current degree of maturity. AUTOSAR is driven by so called core partners: leading car manufacturers (BMW, Daimler, Ford, GM, PSA, Toyota, Volkswagen) together with the tier 1 suppliers Continental and Bosch. AUTOSAR in total has more than 150 companies (OEM, Tier X suppliers, SW and tool suppliers, and silicon suppliers) as members from all over the world.

With the development of start stop technology to improve fuel economy and to reduce carbon dioxide (CO2) emissions, the information of State of Charge (SOC) of the battery is highly desirable. Recent days the battery sensors are used in mid-segment and luxury automobiles that monitors the current, voltage and temperature of the battery and calculates the charge model and sends the information via CAN or LIN. These dedicated sensors are intended to perform various functions other than basic start stop. Hence these sensors are proven to be expensive for emerging market, which is intended to perform only basic start stop as the market is looking for a low cost solution. Bosch- India has developed and implemented a novel idea of bringing a low cost and reliable battery charge detection algorithm that can be realized within the Electronic Control Unit (ECU) without a dedicated sensor.

The SAE J2716 SENT (Single Edge Nibble Transmission) Protocol has entered production with a number of announced products. The SENT protocol is a point-to-point scheme for transmitting signal values from a sensor to a controller. It is intended to allow for high resolution data transmission with a lower system cost than available serial data solution. The SAE SENT Task Force has developed a number of enhancements and clarifications to the original specification which are summarized in this paper.

Active safety systems will have a great impact in the next generation of vehicles. This is partly originated by the increasing consumer's interest for safety and partly by new traffic safety laws. Control actions in the vehicle are based on an extensive environment model which contains information about relevant objects in vehicle surroundings. Sensor data fusion integrates measurements from different surround sensors into this environment model. In order to avoid system malfunctions, high reliability in the interpretation of the situation, and therefore in the environment model, is essential. Hence, the main idea of data fusion is to make use of the advantages of using multiple sensors and different technologies in order to fulfill these requirements, which are especially high due to autonomous interventions in vehicle dynamics (e. g. automatic emergency braking).

The emissions legislation in the US and Europe introduces the need for the application of diesel particulate filters (DPF) in most diesel vehicles. In order to fulfill future OBD legislations, which include more stringent requirements on monitoring the functionality of those particulate filters, new sensors besides the differential pressure sensor are necessary. The new sensors need to directly detect the soot emission after DPF and withstand the harsh exhaust gas environment. Based on multi layer ceramic sensor technology, an exhaust gas sensor for particulate matter (EGS-PM) has been developed. The soot-particle-sensing element consists of two inter-digitated comb-like electrodes with an initially infinite electrical resistance. During the sensor operation, soot particles from the exhaust gas are collected onto the inter-digital electrodes and form conductive paths between the two electrode fingers leading to a drop of the electrical resistance.