Powered two-wheeler riders are frequently involved in crashes at intersections because an approaching car driver fails to give right of way. This simulator study aimed to investigate how riders perform an emergency braking maneuver in response to an oncoming car and, second, whether longitudinal motion cues provided by a motion platform influence riders' braking performance. Twelve riders approached a four-way intersection at the same time as an oncoming car. We manipulated the car's direction of travel, speed profile, and its indicator light. The results showed that the more dangerous the situation (safe, near-miss, impending-crash), the more likely riders were to initiate braking. Although riders braked in the majority of trials when the car crossed their path, they were often unsuccessful in avoiding a collision with the car. No statistically significant differences were found in riders' initiation of braking and braking style between the motion and no-motion simulator configurations.@en

Shimmy oscillations are undesired vibrations in aircraft landing gears. In this chapter, the onset of shimmy vibrations, marked by Hopf bifurcations, is investigated in the parameter space of high-fidelity, flexible multibody landing gear models. Such a bifurcation analysis is performed by combining the Virtual.Lab Motion multibody solver with the numerical continuation software AUTO. The resulting quasi-2-parameter bifurcation diagrams, involving aircraft velocity and normal load, are verified using conventional time-simulation methods and are shown to be computationally more efficient. A sensitivity study reveals the influence of design parameters, such as the shimmy damping coefficient, mechanical trail, and steering actuator stiffness, on the occurrence of shimmy.

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Optimization-based motion cueing algorithms based on model predictive control have been recently implemented to reproduce the motion of a car within the limited workspace of a driving simulator. These algorithms require a reference of the future vehicle motion to compute a prediction of the system response. Assumptions regarding the future reference signals must be made in order to develop effective prediction strategies. However, it remains unclear how the prediction of future vehicle dynamics influences the quality of the motion cueing. In this study two prediction strategies are considered. Oracle: the ideal prediction strategy that knows exactly what the future reference is going to be. Constant: a prediction strategy that ignores every future change and keeps the current vehicle’s linear accelerations and angular velocities constant. The two prediction strategies are used to reproduce a sequence of maneuvers between 0 and 50 km/h. A comparative analysis is carried out to objectively evaluate the influence of the prediction strategies on motion cueing quality. Dedicated indicators of correlation, delay and absolute error are used to compare the effects of the adopted prediction on simulator motion. Also the motion cueing mechanisms adopted by the different conditions are analyzed, together with the usage of simulator workspace. While the constant strategy provided reasonable cueing quality, the results show that knowledge of the future vehicle trajectory reduces the delay and improves correlation with the reference trajectory, it allows the combined usage of different motion cueing mechanisms and increases the usage of workspace.

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This paper presents a X-in-the-loop (where X: Model, Software, Hardware, Driver/Human, etc.) driving simulation platform, developed at Siemens PLM Software, that facilitates the design, development, testing and validation of Advanced Driver Assistance System (ADAS). The paper outlines the essential components of the simulator and demonstrates the usefulness by two autonomous driving functionalities i.e. adaptive cruise control and autonomous intersection crossing. In addition, the paper highlights the key features of the platform.

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As the complexity of high-tech systems continuously increases, engineers look for possibilities to reduce time and cost of the development of these systems. Architecture- based design enables a front-loaded design process with knowledge reuse. By enabling the automatic synthesis of simulation models, different configurations of an architecture can be realized and simulated efficiently. Current practices are found in the automotive and aerospace industry where architecture- based design is used for the automatic synthesis of multi-physics simulation models. In this way, different architecture options and simulation model variations can be efficiently investigated early in the development process. Multi-body simulations are also frequently used in the conceptual design of complex mechatronic systems. However a suitable methodology to synthesize their simulation models is lacking. This paper demonstrates that an architecture-based design approach can be used for the automatic synthesis of multi-body simulation models and a methodology is proposed to efficiently model and synthesize them. However, due to the geometric constraints, geometrical dependencies have been introduced between the sub-systems which requires a correct synthesis sequence that needs to be determined by solving a topological sorting problem. Subsequently, the methodology was evaluated with the conceptual design of an aircraft trailing-edge high-lift system. It was found that, concerning the time efficiency of the proposed approach, a trade-off needs to be made between the time that is saved by the automatic synthesis of simulation models and the time it takes to create the architectures and compatible subsystem models. Finally, the research suggests that an architecture-based design approach can be used for a diverse set of design problems involving different domain specific engineering tools. Therefore, the applicability is not limited to aerospace industry and it can as well bring advantages to other industries where the investigation of conceptual designs is an important but time-intensive activity.

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