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This paper presents an analysis of the motion of a motorcycle at high-speed using a motorcycle dynamics model that considers the compliance of the frame components. Several motorcycle nonlinear dynamics models have been proposed in previous studies and in the industry. However, these models do not consider the compliance of the frame components, which affects the maneuverability and stability of motorcycles. Moreover, there is not any researches that analyzes the effect of such compliance on motorcycle dynamics in a domain that includes turning. In this paper, we derive a nonlinear dynamics model of a motorcycle that takes into account the compliance of the frame components and analyze the effect of such compliance on the vehicle body motion during high-speed straight riding and turning. For the dynamics model, the Kane’s equation is constructed based on multi-body dynamics analysis. In conclusion, we demonstrate that the compliance corresponding to the lateral torsion of the front forks is the most dominant factor in improving stability in the high-speed region, both in straight riding and in turning.

Thin-film sensors were used to measure the oil film pressure distribution at the piston pin-bore interface in order to ascertain the stress distribution on the piston pin of a gasoline engine during actual operation. Thin-film sensors have been manufactured by a sputtering method to a total film thickness of about 3–6 μm. The features of thin-film sensors have been utilized to successfully measure the oil film pressure on engine main bearings, connecting rod bearings and piston skirts of both diesel and gasoline automotive engines. However, as engine lubrication conditions have become more severe year by year, it has become necessary to develop thin-film pressure sensors with higher durability. The use of diamond-like carbon (DLC) coating for the protective film of the thin-film sensor has enabled accurate measurement of oil film pressure under engine operating conditions. The AVL EXCITETM Power Unit was used in simulations with the application of elastic fluid lubrication theory. The calculated values were compared with measured data, and a comparison was made of the effect of the model constraint condition. [ABSTRACT FROM AUTHOR]

Hybrid energy storage systems (HESS) for electric vehicles, which consist of lithium-ion batteries and supercapacitors, have become an increasing focus of research and development in recent years. The combination of the two combines the advantages of each storage technology (high energy density in batteries and high power density in supercapacitors) in one system. To effectively manage the energy flow between these two different storage technologies, an intelligent energy management system (EMS) is required. In the development of the EMS, it is usual to run preliminary checks in a simulation environment that is as close to reality as feasible already during the development process. For this purpose, this paper presents a concept for the creation of a simulation environment consisting of realistic routes and a holistic vehicle model. The realistic route data are generated by a route-generating algorithm, which accesses different map services via application programming interfaces (API) and retrieves real route data to generate a simulated route. By integrating further online services (e.g., OpenWeather API), the routes are further specified with, for example, real weather data, traffic data, speed limits and altitude data. For the complete vehicle model, components including the suspension, chassis and auxiliary consumers are simulated as blackbox models. The components that can be accessed during the simulation are simulated as white box models. These are the battery, the supercapacitor, the DC/DC converter and the electric motor. This allows the EMS to control and regulate the HESS in real time during the simulation. To validate the simulation environment presented here, a real BMW i3 was driven on a real route, and its energy demand was measured. The same route was simulated in the simulation environment with environmental conditions that were as realistic as feasible (traffic volume, traffic facilities, weather) and the vehicle model of the BMW i3. The resulting energy demand from the simulation was recorded. The results show that the simulated energy consumption value differs by only 1.92% from the real measured value. This demonstrates the accuracy of the simulation environment presented here. [ABSTRACT FROM AUTHOR]

Abstract Steering columns for column assist Electric Steering are one of the main elements of the passive safety restraint system in a passenger vehicle. It is designed to collapse applying an optimized ride down force to reduce chest and head injuries of the driver during a frontal crash event, making this requirement one of the most important ones for its development. The system crash response is generated by several elements and interfaces due to the fact of many other different product requirements that a steering column must fulfill. This could lead into a complex validation process throughout the development, as it is needed to integrate the product into the vehicle in order to meet the passive safety requirements. As part of ZF lean Validation approach a new method has been developed to improve the system robustness in ZF Active safety division by means of virtual simulation and six sigma disciplines. This resultant method is also applicable for a model based development process and also contributes to improve frontloading development techniques. An analysis of variance has been done using a correlated virtual model for crash simulation, where the main parameters of the system are known (normally the case when same product generation is reused in a new vehicle). Obtaining as a result of the analysis the regression equation of the system response. This equation defines and quantifies the importance of each factor, and consequently is defining the component contribution and how to develop a column from bottom to top. Moreover, as a second step, a Monte Carlo analysis has been applied using the equation obtained generating statistical results for a number of cases (based in the design tolerances) not manageable from the hardware testing perspective neither from the finite elements methods. In that project Monte Carlo analysis has been applied for 100,000 cases generating response confident intervals instead of the classic FEM deterministic response where only the nominal case is considered.

Manufacturing companies need to go digital. Although this sector leads in automation adoption, some companies struggle to explore emerging innovations such as Cyber-Physical Systems, Digital Twins and "servitisation in manufacturing". The equipment required to deliver production systems typically combines physical and software components, yet digital innovations require investing in new models and tools, and training in model-based design. In this paper, we report on a new collaboration platform fostering the ability to experiment with digital innovations using a sandbox environment, accessible online via the user browser, and with good acceptance in small experiments by members in the manufacturing community. [ABSTRACT FROM AUTHOR]

Hybrid energy storage systems (HESS) for electric vehicles, which consist of lithium-ion batteries and supercapacitors, have become an increasing focus of research and development in recent years. The combination of the two combines the advantages of each storage technology (high energy density in batteries and high power density in supercapacitors) in one system. To effectively manage the energy flow between these two different storage technologies, an intelligent energy management system (EMS) is required. In the development of the EMS, it is usual to run preliminary checks in a simulation environment that is as close to reality as feasible already during the development process. For this purpose, this paper presents a concept for the creation of a simulation environment consisting of realistic routes and a holistic vehicle model. The realistic route data are generated by a route-generating algorithm, which accesses different map services via application programming interfaces (API) and retrieves real route data to generate a simulated route. By integrating further online services (e.g., OpenWeather API), the routes are further specified with, for example, real weather data, traffic data, speed limits and altitude data. For the complete vehicle model, components including the suspension, chassis and auxiliary consumers are simulated as blackbox models. The components that can be accessed during the simulation are simulated as white box models. These are the battery, the supercapacitor, the DC/DC converter and the electric motor. This allows the EMS to control and regulate the HESS in real time during the simulation. To validate the simulation environment presented here, a real BMW i3 was driven on a real route, and its energy demand was measured. The same route was simulated in the simulation environment with environmental conditions that were as realistic as feasible (traffic volume, traffic facilities, weather) and the vehicle model of the BMW i3. The resulting energy demand from the simulation was recorded. The results show that the simulated energy consumption value differs by only 1.92% from the real measured value. This demonstrates the accuracy of the simulation environment presented here.

Steering columns for column assist Electric Steering are one of the main elements of the passive safety restraint system in a passenger vehicle. It is designed to collapse applying an optimized ride down force to reduce chest and head injuries of the driver during a frontal crash event, making this requirement one of the most important ones for its development. The system crash response is generated by several elements and interfaces due to the fact of many other different product requirements that a steering column must fulfill. This could lead into a complex validation process throughout the development, as it is needed to integrate the product into the vehicle in order to meet the passive safety requirements. As part of ZF lean Validation approach a new method has been developed to improve the system robustness in ZF Active safety division by means of virtual simulation and six sigma disciplines. This resultant method is also applicable for a model based development process and also contributes to improve frontloading development techniques. An analysis of variance has been done using a correlated virtual model for crash simulation, where the main parameters of the system are known (normally the case when same product generation is reused in a new vehicle). Obtaining as a result of the analysis the regression equation of the system response. This equation defines and quantifies the importance of each factor, and consequently is defining the component contribution and how to develop a column from bottom to top. Moreover, as a second step, a Monte Carlo analysis has been applied using the equation obtained generating statistical results for a number of cases (based in the design tolerances) not manageable from the hardware testing perspective neither from the finite elements methods. In that project Monte Carlo analysis has been applied for 100,000 cases generating response confident intervals instead of the classic FEM deterministic response where only the nominal case is considered. [ABSTRACT FROM AUTHOR]

Abstract With the spectacular development of pervasive computing and the widespread use of mobile technologies, the user usually resorts to a wide variety of user platforms. Moreover, the applications deployed on such platforms usually lack specific support for people suffering from disabilities. This is especially valid in the Tunisian context where the current status of digital accessibility is far from being perfect since the developer's community still ignores accessibility-related programming techniques. Consequently, further efforts are still required to resolve the issues related to the growing variety of available devices and of accessibility difficulties met by different categories of users. Therefore, in this paper we are introducing a model driven approach that aims to assist local and worldwide communities of developers throughout the development process of accessible user interfaces (UIs) targeting several emerging platforms. Based on a set of models from different abstraction levels followed by transformations, this approach provides a generic framework that integrates accessibility concerns starting from the design time. It allows the generation of accessible interfaces with a focus on the graphical and adaptation aspects on various platforms regardless of the developer expertise in UI accessibility. 1 Highlights • Improving the development of accessible applications for developers worldwide. • Metamodels of accessible user interface, interaction platforms, execution platforms. • Transformations from abstract accessible UI models to executable UIs. • Development of model editors to assist users create required models. • Evaluation of the framework to show the usability and efficiency of the approach. [ABSTRACT FROM AUTHOR]

Highlights • Automated verification of block diagram models. • Slope boundaries as new abstract domain. • Integrated symbolic and interval verification. • Block diagram case studies from research and industry. Abstract Model-based development is increasingly used in embedded systems, which are often deployed in a safety-critical environment. Verification techniques, supporting the development process can not only increase safety, but also help to speed up the process. In many cases models are designed with block diagrams, assisting rapid prototyping. However, automated verification is, thereafter, often applied to the resulting code. Instead of focusing on code, we apply verification techniques to models consisting of block diagrams and MATLAB code. We propose to combine a value and slope range analysis, with symbolic methods. In this way, our concept can not only prove properties in models, but also check rate requirements automatically, which arise from physical constraints of the environment. We evaluate our work in case studies from ongoing research projects. These case studies cover the domains of clinical intensive care, autonomous drone control and driver assistance. All systems are also evaluated with a commercial verification tool, highlighting benefits of the tool and our implementation. [ABSTRACT FROM AUTHOR]

The development of cross domain physical systems (CDPS) inevitably requires integration of different viewpoints from different domains. The authors introduce a comprehensive design framework, which brings different modeling languages and simulation tools seamlessly integrated for developing CDPS. The framework is built on existing technologies from each of systems, software, electrical, mechanical and control domains, and based on the extendable modeling platform, where its ability to combine different design and simulation tools has proven meaningful. The contribution of the study is the intended framework produces auto-generate Simscape/Simulink behavior models in the Simulink environment supported from the descriptive models in SysML standards. This is achieved by combining the SysML modeling tool with Simscape/Simulink simulation tools using a customized plug-in in order to keep different models in sync. Consequently, the design information can be exchanged amongst development teams for effective decision making and proper documentation without shifting between numerous design tools. [ABSTRACT FROM AUTHOR]

The performance of electric bicycles for the mountainous region depends on a simulation model and experimental study covers dynamic characteristics, power requirement to propel the electric cycle, and different operating conditions such as slope gradient, a mass of the user, wind speed, wheel diameter, and length of the crankshaft. The study highlights the mathematical model of the electric bicycle with dynamic characteristics and calculates the power required to propel the cycle in the mountainous region under a parallel hybrid mode. The application is supported with an android operating system, which keeps track of the cycle issued to potential users. The system has a mechanism in place, which issues the cycle to only those users who unblock it through the application by scanning the correct quick response code. The Simulink is used for mathematical model development and analyzing dynamic characteristics of the electric bicycle. The dSPACE development board framework is used for the experimental validation as a solver to capture multiple input-output parameters. The results show that an electric bicycle motor generates 23.87 Nm of torque at 8 km/h and requires 240 W of power to propel the electric cycle at 34 km/h. The electric bicycle consumes an average current of 8.2 A at a zero slope gradient. It also shows that required power changes to 260 W at 2. 9 o slope gradient, 310 W at 4. 8 o slope gradient and 350 W at 7. 1 o slope gradient. [ABSTRACT FROM AUTHOR]

In system-level design, it is difficult to achieve a system verification which fulfils the requirements of various stakeholders using only descriptive system models. Descriptive system models using SysML alone are insufficient for system behaviour verifications and engineers always use different simulation tools (e.g., the Mathworks Simulink or Modelica Dymola) to analyze systems behaviour. It is a good idea to combine descriptive and simulation models. This paper presents the development of a collaborative design framework which brings SysML, Simulink, and Simscape profiles within the domain of robotics. A conceptual design method is proposed to support execution models for simulation. In brief, the descriptive SysML system-level model is interpreted into the system-level simulation models (e.g., Simulink and Simscape). We then use a plugin-based model integration technique to keep both models in sync for automatic simulation. A simulation study is performed to evaluate the system. To illustrate the design of this system, we present a simulated closedloop system.en [ABSTRACT FROM AUTHOR]

Advances in scheduling theory have given designers of control systems greater flexibility over their choice of timing requirements. This could lead to systems becoming more responsive and more maintainable. However, experience has shown that engineers find it difficult to exploit these advantages due to the difficulty in determining the ‘real’ timing requirements of systems and therefore the techniques have delivered less benefit than expected. Part of the reason for this is that the models used by engineers when developing systems do not allow for emergent properties such as timing. The paper presents an approach and framework for addressing the problem of identifying an appropriate and valid set of timing requirements in order that the best use can be made of the advances in scheduling theory by the use of modelling techniques that allow for emergent properties such as timing behaviour. [Copyright &y& Elsevier]