The vehicle development process is a complex venture that involves the entire organization for years. Relying merely on heterogeneous simulation efforts and physical prototypes for vehicle-level verification and validation carries severe risks. A new approach is required to enable continuous vehicle-level verification and validation in all phases of the vehicle development process. Based on the principles of systems engineering, model-based systems engineering, and product lifecycle management, the concept of an Integrated and Open Development Platform (IODP) is proposed as a solution. At the core of this platform are virtual prototypes. They extend the utilization of prototypes to the early phases of the vehicle development process by systematically combining simulation models and hardware on test beds. In virtual prototypes, simulation models and hardware can be integrated and used indistinctly, which enable continuous verification and validation. The IODP backbone strategy and virtual prototype management are proposed as a holistic approach to establish virtual prototypes in an organization and utilize them in the vehicle development process. Real-world implementations and benefits of the proposed approaches are demonstrated in three selected case studies.

Future automotive technologies become more and more autonomous and connected. This trend requires a rethinking of validation processes due to the amount of test kilometers needed. To be able to test automated and connected functions in many different traffic scenarios, virtual and mixed real-virtual prototypes will be used. Moreover, due to the complexity of such systems, cross-company cooperation is increasing and demands for common prototypes. Spatially distributed prototypes simplify and enhance cross-company collaboration due to faster provisioning of models and better IP protection. However, the setup of such prototypes is very time consuming due to the high integration effort. Here it is shown that the integration effort of spatially distributed prototypes can be massively reduced by using the Distributed Co-Simulation Protocol (DCP). A demonstrator consisting of a small scale test bed located in Graz and a co-simulation containing Bosch driving functions located in Renningen is presented. The demonstrated integration workflow as well as an analysis of the communication challenges of the coupling can be transferred to any other coupling of this kind.

Virtual system development gets more and more important in many industrial domains. It is considered to reduce development times, lower computing costs, and shorten time-to-market. Co-simulation is a particularly promising approach for modular and interoperable development. In practice the integration and coupling of heterogeneous systems still require enormous efforts. The configuration and operation of distributed hardware-in-the-loop systems and simulations contribute to efficiency of testing. Currently no standardized interface or protocol specification is available, which allows the interaction of real-time and non-real-time systems of different vendors. This paper for the first time presents the Distributed Co-simulation Protocol (DCP) which is subject to proposal as a standard for real-time and non-real-time system integration and simulation. The DCP consists of a data model, a finite state machine, and a communication protocol including a set of protocol data units. It is designed as a tool independent standard. It was developed in context of the ACOSAR project and is subject to standardization as a Modelica Association Project (MAP). It enables the definition, configuration and execution of a wide range of different simulations and test scenarios. It supports a master-slave architecture for simulation setup and control. The specification defines the design of a slave only, the design of a master is not in scope of the specification. To highlight the industrial applicability of the DCP, three examples from the automotive domain are shown.

This work presents a control strategy to control a magnetic levitation system under the influence of coupling imperfections (disturbances). To overcome problems arising whenever the interconnections between plant and controller have a non-negligible influence on the control-loop behavior a so-called model-based coupling approach is used. The main idea of this coupling approach is to use prediction schemes based on recursively identified plant and controller models which compensate for performance degradation due to coupling imperfections. Coupling failures such as time-delays, data-losses and noise drastically influence the control-loop performance. Especially when systems in form of real hardware (real-time systems) are present such disturbances have to be handled adequately. To demonstrate the effectiveness of the model-based coupling approach, a control-loop of a magnetic levitation system is analyzed in simulation as well as in real world laboratory setup (HiL simulation). Furthermore a first insight into the stability analysis of closed-loop systems including the model-based coupling technique is performed for a simplified configuration.

The coupling of real-time and non-real-time systems is directly related to different types of faults which require adequate handling. These faults, such as communication time-delays, data-loss or noisy measurements, originate from the incorporation of real hardware (real-time system) and lead to significant challenges in the coupling process. Without compensating their destabilizing effects the simulation results are corrupted. Ignoring those effects can even result in unstable closed-loop systems in the worst case, which may in turn result in hardware damage. This work proposes a recursive FIR-filter design approach which compensates such fault effects. The effectiveness of the proposed coupling filters is demonstrated by a representative example.

This paper presents an integral sliding mode (ISM) formulation for the torque-vectoring (TV) control of a fully electric vehicle. The performance of the controller is evaluated in steady-state and transient conditions, including the analysis of the controller performance degradation due to its real-world implementation. This potential issue, which is typical of sliding mode formulations, relates to the actuation delays caused by the drivetrain hardware configuration, signal discretization, and vehicle communication buses, which can provoke chattering and irregular control action. The controller is experimentally assessed on a prototype electric vehicle demonstrator under the worst-case conditions in terms of drivetrain layout and communication delays. The results show a significant enhancement of the controlled vehicle performance during all maneuvers.

Development of wheel slip control for ground vehicles with electric powertrain belongs to the one of the most challenging problems in automotive control engineering. The realization of the wheel slip control for anti-lock brake (ABS) and traction control (TC) systems is a more complex task in the case of vehicles designed both for on-road and off-road conditions. In this situation a control strategy must be able to handle different tyre-surface contact dynamics. Within this context, the presented paper introduces the wheel slip control and corresponding ABS algorithm developed for the all-wheel drive sport utility electric vehicle with four individually controlled on-board motors. The proposed paper, in particular, includes: Analysis of state-of-the art solutions for off-road ABS; Description of the developed ABS architecture based on the direct wheel slip control with predictive and reactive wheel torque contributions; Results of ABS operation in the vehicle simulator software with special attention given to the braking on rough surface; Procedure of the system tuning using hardware-in-the-loop technique; Experimental results of the system testing on the vehicle demonstrator in real operational conditions. The theoretical and experimental outcomes have confirmed improved functionality of the developed wheel slip control in terms of vehicle safety and energy efficiency. (C) 2015 ISTVS. Published by Elsevier Ltd. All rights reserved.

Diese Arbeit behandelt die sogenannte Echtzeit-Co-Simulationsproblematik. Im Speziellen wird die Einbindung von Hardwarekomponenten in einen Softwareverbund durch kommunikationsbedingte Latenzzeiten und Messrauschen erschwert. Zur Behandlung dieser Störungen wird ein modellbasierter Kopplungsansatz vorgestellt. Mittels Prädiktion von Koppelgrößen können die Auswirkungen von Störeinflüssen deutlich reduziert werden. Die Effektivität dieses Kopplungsansatzes wird an einem Labormodell demonstriert. Darüber hinaus werden einige typische industrielle Anwendungsszenarien skizziert.

(please use Times New Roman, 12 pt., max. 400 words) The co-simulation approach allows development departments (typically different domains) to use their most suitable simulation tools for subsystem modeling of an overall mechatronic product e.g. the entire vehicle. Applying this approach a flexible and efficient vehicle development process considering different departments respectively domains is possible. This approach addresses the left branch of the well-known V-model. To extend the co-simulation approach to the right branch of the V-model a so called real-time co-simulation problem has to be solved. The right branch, which represents the advanced product development stage, is characterized by the integration of real-hardware in form of control units, HiL test systems or whole test beds. This incorporation of real-time systems is directly connected with new coupling challenges as real communication media and sensors are present: the coupling of the involved systems has to be time correct; round-trip-times must be kept as small as possible in order to ensure the stability of existing control loops; noisy sensor signals must be taken into account; coupling data losses has to be handled adequately. So offline simulation models, typically with a high level of detail, test scenarios or environment simulations can be used with the real test equipment without the necessity of model conversion and/or code generation. In conclusion the real-time co-simulation concept enables the application of the classical co-simulation techniques during the whole product development process (V-model). To demonstrate the application of the (real-time) co-simulation approach during the whole development process an entire vehicle simulation is presented. The entire vehicle consists of three different subsystems, which are linked via AVL Model connect: the drivetrain modeled in AVL Cruise or MSC Adams, an ABS control unit modeled in Matlab/Simulink or AMESim and the rest of the vehicle modeled. To address also the right branch of the V-model the ABS control unit is also integrated in form of a real-time system (dSpace MicroAutoBox) via the real-time cosimulation approach. Beside the presentation of the real-time co-simulation approach also a flexible subsystem exchange (variability) is addressed via this example. AVL Advanced Simulation Technologies International User Conference 2015 Abstract Tractor & Implement optimization by combined vehicle and powertrain consideration Authors (please underline main author): Gerhard Putz, Mario Oswald Company/ University, Department: AVL, Driveability & Simulation Department

Non-iterative co-simulation is a prerequisite for the time correct coupling of distributed solved numerical problems. For this coupling approach typically signal-based extrapolation schemes are used to resolve existing bidirectional dependencies between the interacting subsystems. Nevertheless, the introduced coupling errors influence the entire system behavior. In the case of coupled real-time systems inherent time-delays and noisy measurements lead to significant additional distortions. Thus, to avoid a deteriorating dynamic behavior of coupled systems - which can even lead to instability - new coupling approaches are mandatory. A model-based extrapolation scheme is motivated to realize a compensation of the occurring round-trip-times and noise-handling. Besides the description of the fundamentals a representative example demonstrates the effectiveness of the proposed coupling approach.

This paper proposes a model based coupling technique for interconnected systems. It helps to overcome problems arising whenever the interconnections have a non-negligible influence on the overall system behavior. The main idea of the method is to use prediction schemes which compensate for performance degradation due to coupling imperfections. Exemplarily the so-called co-simulation scenario is selected to demonstrate the principles of the presented approach and its effectiveness by means of a complex real-time application.

Although the implementation of the 48V voltage supply in next generation passenger vehicles is certain to go ahead, economic and technical challenges remain to be overcome. The cost of lithium based batteries is falling, but costs for energy and power per liter/kg still remain an impediment to the application of the new voltage domain in high volumes. Engine cold-start, aging, efficient use of available energy and effective battery management systems are all facing problems that require technical solutions. ams AG provides (cost)-efficient IC solutions for lithium based battery systems, in-vehicle communication and power supplies for electronic modules for 48V systems. The Virtual Vehicle Competence Center provides the co-simulation environment for system integration and simulation-based evaluation of these systems.