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The development of perception functions for tomorrow’s automated vehicles is driven by enormous amounts of data: often exceeding a gigabyte per second and reaching into the terabytes per hour. Data is typically gathered by a fleet of dozens of mule vehicles which multiply the data generated into the hundreds of petabytes per year. Traditional methods for fueling data-driven development would record every bit of every second of a data logging drive on solid-state drives located on a PC in the vehicle. Recorded data must then be exported from these drives using an upload station which pushes to the data lake after arriving back at the garage. This paper considers different techniques for curating logged data.

The advancement of both sensory and unmanned technology, combined with increased utilization of autonomous platforms in complex teaming scenarios, has created a need for practical design space exploration tools to aid in the synthesis of effective System-of-Systems (SoS). The presented work describes a modular, flexible, and extensible framework, referred to herein as the Technologies and Teaming Evaluation (TATE) framework, for straightforward identification of high-quality SoS, which may include both manned and autonomous elements, through quantitative evaluation of system-level and SoS-level attributes against a set of user-defined reference tasks.

This paper presents a demonstrator developed in the European CleanSky2 project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). Its scope is the development towards a seamless integrated, interconnected toolchain enabling more efficient processes with less rework time in todays, highly collaborative aerospace domain design applications. The demonstration described here, consists of an open, modular and multitool platform implementation, using specific techniques to achieve fully traceable (early stage) requirements verification by virtual testing. The most promising approach is a model based integration along the whole process from requirements definition to the verified, integrated (and certified) system. Extending previous publications in this series, the paper introduces the motivation and briefly describes the technical background and a potential implementation of a workflow suitable for that target.

Automation on Validation and Verification (V&V) leveraging Formal Methods, and in particular Model Checking, is seeing an increasing use in the Aerospace domain. In recent years, Formal Methods have been used to verify systems and software and its correctness as a way to augment traditional methods relying on simulation and testing. Recent updates to the relevant Aerospace regulations (e.g. DO178C, DO331 and DO333) now have explicit provisions for utilization of models and formal methods. In a previous paper a compositional methodology for the verification of Aerospace Systems has been described with application to Electrical Power Generation and Distribution Systems. In this paper we present an expansion of the previous work in two directions. First, we describe the application of the methodology to the validation of Proximity Sensing Systems (PSS) requirements showing the effectiveness of the method to a new aerospace domain.

In the aerospace industry, methods for virtual testing cover an increasing range of test executions carried out during the development and test process of avionics systems. Over the last years, most companies have focused on questions regarding the evaluation and implementation of methods for virtual testing. However, it has become more and more important to seamlessly integrate virtual testing into the overall development process. For instance, a company’s test strategy might stipulate a combination of different methods, such as SIL and HIL simulation, in order to benefit from the advantages of both in the same test process. In this case, efforts concentrate on the optimization of the overall process, from test specification to test execution, as well as the test result evaluation and its alignment with methods for virtual testing.

Hybrid test systems are gaining more and more significance in the aerospace industry. At the heart of these systems is a standardized communication infrastructure. There are many challenges when designing the communication infrastructure. For example, it requires very specific knowledge to boot a hybrid system, manage its configuration process, and start and stop the execution of applications, such as simulations, panels or recorders. Likewise, when testers use a heterogeneous test environment, they cannot commit themselves too much to every single test means and its special characteristics. Nevertheless, testers must always be able to monitor and control every test system. This means, they must be able to determine the current overall system status and the current status of its components and parts. Examples for this are hardware components, such as real-time processors and I/O boards, as well as software applications, such as real-time simulations models on the test system.

Multi-physics interactions between structural, electrical, thermal, or hydraulic components and the high level of system integration, characteristic of new aircraft designs, is increasing the complexity of both design and verification processes. Therefore the availability of tools, supporting integrated modelling, simulation, optimization and testing across all stages of aircraft design remains a critical challenge. This paper presents some results of the project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). It is a collaborative task being developed under the European Union Clean Sky 2 Program, which is a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The first levels of integration of different models and tools proposed in the MISSION framework will be presented, along with simulation results.

The complexity of automobile powertrains grows continuously. At the same time, development time and budget are limited. Shifting development tasks to earlier phases (frontloading) increases the efficiency by utilizing test benches instead of prototype vehicles (road-to-rig approach). Early system verification of powertrain components requires a closed-loop coupling to real-time simulation models, comparable to hardware-in-the-loop testing (HiL). The international research project Advanced Co-Simulation Open System Architecture (ACOSAR) has the goal to develop a non-proprietary communication architecture between real-time and non-real-time systems in order to speed up the commissioning process and to decrease the monetary effort for testing and validation. One major outcome will be a generic interface for coupling different simulation tools and real-time systems (e.g. HiL simulators or test benches).

Increasing diagnosis capabilities in modern engine electronic control units (ECUs), especially in the exhaust path, in terms of emission and engine aftertreatment control utilize on-board NOx prediction models. Nowadays it is an established approach at hardware-in-theloop (HIL) test benches to replicate the engine's steady-state NOx emissions on the basis of stationary engine data. However, this method might be unsuitable for internal ECU plausibility checks and ECU test conditions based on dynamic engine operations. Examples of proven methods for modeling the engine behavior in HIL system applications are so-called mean value engine models (MVEMs) and crank-angle-synchronous (in-cylinder) models. Of these two, only the in-cylinder model replicates the engine’s inner combustion process at each time step and can therefore be used for chemical-based emission simulation, because the formation of the relevant gas species is caused by the inner combustion states.

The application of a communication infrastructure for hybrid test systems is currently a topic in the aerospace industry, as also in other industries. One main reason is flexibility. Future laboratory tests means (LTMs) need to be easier to exchange and reuse than they are today. They may originate from different suppliers and parts of them may need to fulfill special requirements and thus be based on dedicated technologies. The desired exchangeability needs to be achieved although suppliers employ different technologies with regard to specific needs. To achieve interoperability, a standardized transport mechanism between test systems is required. Designing such a mechanism poses a challenge as there are several different types of data that have to be exchanged. Simulation data is a prominent example. It has to be handled differently than control data, for example. No one technique or technology fits perfectly for all types of data.

This paper will present a multi-domain (electrical and thermal) model of a three phase voltage source converter and its implementation in Modelica language. An averaged model is utilised for the electrical domain, and a power balance method is used for linking the DC and AC sides. The thermal domain focuses in deriving the converter losses by deriving the analytical equations of the space vector modulation to derive a function for the duty cycle of each converter leg. With this, the conduction and switching losses are calculated for the individual switches and diodes, without having to model their actual switching behaviour. The model is very fast to simulate, as no switching events are needed, and allows obtaining the simulation of the electrical and thermal behaviour in the same simulation package..

This paper presents an overview of a project called “Modelling and Simulation Tools for Systems Integration on Aircraft (MISSION)”. This is a collaborative project being developed under the European Union Clean Sky 2 Program, a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The provision of integrated modeling, simulation, and optimization tools to effectively support all stages of aircraft design remains a critical challenge in the Aerospace industry. In particular the high level of system integration that is characteristic of new aircraft designs is dramatically increasing the complexity of both design and verification. Simultaneously, the multi-physics interactions between structural, electrical, thermal, and hydraulic components have become more significant as the systems become increasingly interconnected.

It is desired to reduce stator end winding length and mass to reduce associated resistive losses, increase efficiency and power density of an induction motor. With recent advancements in additive manufacturing technology, it is possible to deposit copper conductive paths and insulation layers in a selective controlled manner. This enables more compact end winding designs. The objective of this paper is to present a topology optimization based approach for design of stator end winding to minimize its overall length, volume and mass. Design approach and parametric study results for a representative stator design are presented in this paper. By reducing length of end winding, efficiency and power density of the induction motor can be increased enabling benefit realization for weight critical aerospace applications, incorporation in electric vehicle market and potentially reducing rare-earth dependency.

Auto transformer rectifier units (ATRUs) are commonly used in aircraft applications such as electric actuation for harmonic mitigation due to their high reliability and relative low cost. However, those components and the magnetic filter components associated to it are the major contributors to the overall size and weight of the system. Optimization of the magnetic components is essential in order to minimize weight and size, which are major market drivers in aerospace industry today. This requires knowledge of the harmonic content of the current. This can be obtained by simulation, but the process is slow. In order to enable fast and efficient design space exploration of optimal solutions, an algebraic calculation process is proposed in this paper for multi-pulse ATRUs (e.g. 12-pulse and 18-pulse rectifiers), starting from existing solution proposed for 6 pulse rectifier in the literature.

Formal Methods, and in particular Model Checking, are seeing an increasing use in the Aerospace domain. In recent years, Formal Methods are now commonly used to verify systems and software and its correctness as a way to augment traditional methods relying on simulation and testing. Recent updates to the relevant Aerospace regulations (e.g. DO178C, DO331 and DO333) now have explicit provisions for utilization of models and formal methods. At the system level, Model Checking has seen more limited uses due to the complexity and abstractions needed. In this paper we propose several methods to increase the capability of applying Model Checking to complex Aerospace Systems. An aircraft electrical power system is used to highlight the methodology. Automated model-based methods such as Cone of Influence and Timer Abstractions are described. Results of those simplifications, in combination with traditional Assume-Guarantee approaches will be shown for the Electric Power System application.

Increasing productivity along the development and verification process of safety-related projects is an important aspect in today’s technological developments, which need to be ever more efficient. The increase of productivity can be achieved by improving the usability of software tools and decreasing the effort of qualifying the software tool for a safety-related project. For safety-critical systems, the output of software tools has to be verified in order to ensure the tools’ suitability for safety-relevant applications. Verification is particularly important for test automation tools that are used to run hardware-in-the-loop (HIL) tests of safety-related software automatically 24/7. This qualification of software tools requires advanced knowledge and effort. This problem can be solved if a tool is suitable for developing safety-related software. This paper explains how this can be achieved for a COTS test automation tool.

Advanced driver assistance systems (ADAS) are becoming increasingly important for today's commercial vehicles. It is therefore crucial that different ADAS functionalities interact seamlessly with existing electronic control unit (ECU) networks. For example, autonomous emergency braking (AEB) systems directly influence the brake ECU and engine control. It has already become impossible to reliably validate this growing interconnectedness of control interventions in vehicle behavior with prototype vehicles alone. The relevant tests must be brought into the lab at an earlier development stage to evaluate ECU interaction automatically. This paper presents an approach for using hardware-in-the-loop (HIL) simulation to validate ECU networks for extremely diverse ADAS scenarios, while taking into account real sensor data. In a laboratory environment, the sensor systems based on radars, cameras, and maps are stimulated realistically with a combination of simulation and animation.

Hardware-in-the-loop (HIL) testing is indispensable in the software development process for control units and has been an integral part of the software development process for years. Large HIL systems for integration tests are used to test the correct behavior of distributed functions and the communication between the control units. The vast development programs that are involved require building duplicates of such test systems or parts of them, due to the fact that the tasks are distributed between different companies or different departments within a company. However, there is an alternative to duplicating a test system. Instead of using a cloned system, coupling HIL systems over large distances is an alternate approach. This paper presents what requirements this coupling must fulfill and and describes a path-breaking method to fulfill them. In addition, results of an implementation are shown.

To make the development of complex aircraft systems manageable and economical, tests must be performed as early as possible in the development process. The test goals are already set in advance before the first hardware for the ECUs exists, to be able to make statements about the system functions or possible malfunctions. This paper describes the requirements on and solutions for test systems for ECUs that arise from these goals. It especially focuses on how a seamless workflow and consistent use of test systems and necessary software tools can be achieved, from the virtual test of ECUs, which exist only as models, up to the test of real hardware. This will be shown in connection with a scalable, fully software-configurable hardware-in-the-loop (HIL) technology. The paper also covers the seamless use of software tools that are required for HIL testing throughout the different test phases, enabling the reuse of work products throughout the test phases.

Model-based development is the established way of developing embedded control algorithms, especially for safety-critical applications. The aim is to improve development efficiency and safety by developing the software at a high abstraction level (the model) and by generating the implementation (the C code) automatically from the model. Although model-based development focuses on the models themselves, downstream artifacts such as source code or executable object code have to be considered in the verification stage. Safety standards such as ISO 26262 require upper bounds to be determined for the required storage space or the execution time of real-time tasks, and the absence of run-time errors to be demonstrated. Static analysis tools are available which work at the code level and can prove the absence of such errors. However, the connection to the model level has to be explicitly established.