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This paper presents a response to the question: Simulation - mathematical manipulation or useful design tool? A mathematical model of a modulating valve in a transmission control system was developed to predict clutch pressure modulation characteristics. The transmission control system was previously reported in SAE Paper 850783 - “Electronic/Hydraulic Transmission Control System for Off-Highway Vehicles”. The comparison of simulation predictions with test data illustrates the effectiveness of simulation as a design tool. THE EVOLUTION OF COMPUTER hardware and simulation software has resulted in increased interest and usage of simulation for dynamic analysis of hydraulic systems. Most commercially available software is relatively easy to learn to use. The application of such software and the modeling techniques involved require a longer learning curve.

When we see a tangible creation and our inquisitive nature crave to have touch and feel of the same, many questions hover our mind like what it is, what does it do and how it was made. All man-made creations which first get conceived in human mind pass through several processes and evaluation in order to be eventually ready for usage and application. The evaluation and reviews are required so that the final product which is a part of the creation, functions the same as it was intended to do. The analysis which could be limited to part level or system level gives us a foresight into any possibility of pre-production or pre-release failures which might be barriers in the success of the product. Tolerance stack up is one of such analysis approaches used today in product design to understand how imperfections in parts as they are manufactured, and later assembled as products, affect its capability to meet customer requirements.

Software systems on electronically controlled diesel truck engines typically provide diagnostic features to enable the engine mechanic to identify and debug system problems. As future systems become more sophisticated, so will the diagnostic requirements. The advantages of serviceability and accuracy found in todays electronic systems must not be allowed to degrade due to this increased sophistication. One method of maintaining a high level of serviceability and accuracy is to place an even greater priority on diagnostics and servicing in the initial design phase of the product than is done today. In particular, three major goals of future diagnostic systems should be separation of component failures from system failures, prognostication of failures and analysis of engine performance. This paper will discuss a system to realize these goals by dividing the diagnostic task into the Electronic System Diagnostics, Engine System Diagnostics and the Diagnostic Interface.

As safety compliance (ISO 26262) has become a norm for automotive embedded software development, the OEMs and Tier1 are pushed to follow the safety guidelines during hardware, software development process. This demands the microcontroller to not only detect internal faults but also find the exact root cause of the failure and have a self-healing mechanism. This paper presents proposed fault detection, injection, testing and shows comparison of microcontroller fault handling with respect to ISO26262 safety standard between proposed method and traditional method by giving the example of RAM test. Also gives an overview of software implementation of this concept as per AUTOSAR standard.

Electronics technology has evolved significantly since the first electronically controlled heavy duty on-highway truck engines were introduced in the mid 1980's. Engine control hardware, software, and sensor designs have been driven by many factors. Emissions regulations, fuel economy, engine performance, operator features, fleet management information, diagnostics, vehicle integration, reliability, and new electronics technology are some of those factors. The latest engine electronics technology is not only found in heavy duty on-highway trucks, but in off-highway applications as well. Track-type tractors, haul trucks, wheel loaders, and agricultural tractors now benefit from the advantages of electronic engines. And, many more new applications are being developed.

A modern vehicle consists of multiple controllers that communicate with each other on a network to orchestrate the various operations of the vehicle in a coordinated manner. Most often, such networks are based on CAN (Controller Area Network). CAN was primarily implemented to allow for exchange of information on the network to accomplish optimal vehicle functionality. However this information need not be confined to data required by other controllers on the network. This information may also be used to expose the internal functioning of the controller and may be targeted to a special debug node that can extract and decipher this information. Such information can be evaluated to vastly augment debug capabilities while a particular controller is installed on the vehicle. This paper chronicles the authors' experience in developing such a methodology based on the J1939 CAN protocol, and illustrates its use using real world examples.