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Lithium-ion and Lithium polymer batteries are fast becoming ubiquitous in high-discharge rate applications for military and non-military systems. Applications such as small aerial vehicles and energy transfer systems can often function at C-rates greater than 1. To maximize system endurance and battery health, there is a need for models capable of precisely estimating the battery state-of-charge (SoC) under all temperature and loading conditions. However, the ability to perform state estimation consistently and accurately to within 1% error has remained unsolved. Doing so can offer enhanced endurance, safety, reliability, and planning, and additionally, simplify energy management. Therefore, the work presented in this paper aims to study and develop experimentally validated mathematical models capable of high-accuracy battery SoC estimation.

Validating the safety of Highly Automated Vehicles (HAVs) is a significant autonomy challenge. HAV safety validation strategies based solely on brute force on-road testing campaigns are unlikely to be viable. While simulations and exercising edge case scenarios can help reduce validation cost, those techniques alone are unlikely to provide a sufficient level of assurance for full-scale deployment without adopting a more nuanced view of validation data collection and safety analysis. Validation approaches can be improved by using higher fidelity testing to explicitly validate the assumptions and simplifications of lower fidelity testing rather than just obtaining sampled replication of lower fidelity results. Disentangling multiple testing goals can help by separating validation processes for requirements, environmental model sufficiency, autonomy correctness, autonomy robustness, and test scenario sufficiency.

Software testing is all too often simply a bug hunt rather than a well-considered exercise in ensuring quality. A more methodical approach than a simple cycle of system-level test-fail-patch-test will be required to deploy safe autonomous vehicles at scale. The ISO 26262 development V process sets up a framework that ties each type of testing to a corresponding design or requirement document, but presents challenges when adapted to deal with the sorts of novel testing problems that face autonomous vehicles. This paper identifies five major challenge areas in testing according to the V model for autonomous vehicles: driver out of the loop, complex requirements, non-deterministic algorithms, inductive learning algorithms, and fail-operational systems.

Thanks to its unsurpassed power-to-weight ratio, its low package space and low-maintenance design, the loop-scavenged two-stroke engine with conventional mixture preparation is still being used in some sectors of vehicle engineering, such as boat drives, snow mobiles and motor scooters, as well as in hand-held applications. To maintain the potential of the 2-stroke engine for the future it is necessary to take adequate steps against the system-dependent disadvantage of the simple 2-stroke engine, namely that of higher emissions compared to 4-stroke engines. One possible solution is gasoline direct injection. Its more frequent use will increase the production numbers, making it an interesting technology even in the above-mentioned cost-sensitive applications. The current report presents various concepts of direct injection in 2-stroke engines, from air-assisted injection through to high-pressure direct injection, and compares them with traditional techniques of mixture formation.

In the last years short distance radar (SDR) systems were developed for advanced safety applications. Near future production cars are expected to be equipped with multiple SDR sensors to allow an all around sensing of the vehicle's environment and therefore offer a versatile tool for occupant as well as pedestrian protection. On the other hand, another way to make traffic more safe is to establish inter-vehicle communication (IVC) systems that are able, for example, to inform the following traffic about possible hazards. This paper proposes an innovative device approach, the communication radar, for the fi rst time. A basic concept for a SDR based communication system for IVC is decribed. The system is based on a 24 GHz pulse SDR sensor and is designed to allow simultaneous sensing over a range of 20 m and communication at 1 Mbit/s up to 200 m range.

We propose a novel method to real-time in-cylinder pressure estimation by processing structure-borne sound measurements. It has been shown that knowledge of the in-cylinder pressure opens the door to robust misfire detection and sophisticated closed loop engine control schemes. However, the costs of such sensors have inhibited their use in production engines. On the other hand, acceleration sensors are of low cost and already mounted on modern production engines for knock detection. Since structure-borne sound is measured on the surface of the engine, all cylinders are simultaneously observed by one sensor. A simple physically based model, describing the speed dependence of the transfer behavior from each in-cylinder pressure to structure-borne sound is developed. Based on this model, a method for identifying the parameterized transfer function speed independently is developed.