Design for Pedestrian Protection

Pedestrians are among the most vulnerable participants in current city traffic. While in the past original equipment manufacturers (OEMs, in meanings of carmakers) mainly focused on passenger safety, nowadays strict legislation requirements call for the development of more effective pedestrian safety concepts. Considerations for constructive and technological road safety measures generally take place in a company-specific product development process, but mainly in phases, that do not allow for innovative products in terms of new solutions. Thus, the importance of early development phases as well as design process models, such as Pahl and Beitz, will be described here. Also the significance of the development design cases will be handled, as they can mainly influence the innovation degree of the resulting products. In the end an approach will be introduced, of how an analysis of product models regarding their possibilities for adequate evaluation can help, to support a safety-related development process by integrating suitable design methods and tools.

ISO 26262 Concept Phase Analysis on Distributed Electro-Hydraulic Braking System: The Influence of System Architecture on ASIL Decomposition

The Distributed Electro-hydraulic Braking system (DEHB) is a wet type brake-by-wire system. As a safety critical automotive electrical and/or electronic (E/E) system, DEHB shall be designed under the guideline of ISO 26262 in order to avoid unreasonable risk due to the malfunctions in the item. This paper explores how the Automotive Safety Integrity Level (ASIL) decomposition in the concept phase is influenced by the system architectures of DEHB. Based on a typical hazardous event, analysis on DEHB with the same system architecture as the Electro-mechanical Braking system (EMB) is carried out, which is taken as the basis for comparison. Two types of DEHB with different system architectures are then analyzed. Results show that the adoption of hydraulic backup enables ASIL decomposition in the pedal unit. The adoption of both hydraulic backup and normally open balance valves offers the opportunity to perform ASIL decomposition in the brake actuator system of DEHB.

Investigating the Use of Large-Scale Immersive Computing Environments in Collaborative Design

Successful collaborative design requires in-depth communication between experts from different disciplines. Many design decisions are made based on a shared mental model and understanding of key features and functions before the first prototype is built. Large-Scale Immersive Computing Environments (LSICEs) provide the opportunity for teams of experts to view and interact with 3D CAD models using natural human motions to explore potential design configurations. This paper presents the results of a class exercise where student design teams used an LSICE to examine their design ideas and make decisions during the design process. The goal of this research is to gain an understanding of (1) whether the decisions made by the students are improved by full-scale visualizations of their designs in LSICEs, (2) how the use of LSICEs affect the communication of students with collaborators and clients, and (3) how the interaction methods provided in LSICEs affect the design process. The results of this research indicate that the use of LSICEs improves communication among design team members.

Correlating Student Motivation to Course Performance in Capstone Design

This paper presents the preliminary results of a motivational study of students enrolled in their capstone design course during their senior year in mechanical engineering at the Florida Institute of Technology. Student teams are assigned a project and teams are tasked with completing a design project over a one-year (2 semesters) span. Data is collected during the beginning of the fall semester and during the end of the spring semester. Two methods were used to collect the data of the class. A live interview was conducted for each of the capstone teams. Within this interview, a range of questions are asked to facilitate an understanding of what motivates the student. An adaptation of the Motivated Learning Strategies Questionnaire (MSLQ) survey instrument was also administered to the students to collect quantitative data. The MSLQ framework divides the instruments into two sets of questions to address motivation and learning. Motivation is comprised of three factors: test anxiety, self-efficacy, and intrinsic value. Statistical analysis is performed on the quantitative data to determine significance or correlation between student motivation and performance. Performance is measured through the student’s grade (evaluated by instructor) and peer evaluation (evaluated by team). The analysis is performed through segmenting the sample into international versus domestic, and males versus females; to identify any differences in motivation between the groups. Results indicate there are differences between international and domestic students along all motivational factors. Further, differences are identified between males and females for intrinsic anxiety motivational factors.

A Feedback Control Strategy for Torque-Vectoring of IWM Vehicles

In last decades hybrid and electric vehicles have been one of the main object of study for automotive industry. Among the different layout of the electric power-train, four in-wheel motors appear to be one of the most attractive. This configuration in fact has several advantages in terms of inner room increase and mass distribution. Furthermore the possibility of independently distribute braking and driving torques on the wheels allows to generate a yaw moment able to improve vehicle handling (torque vectoring). In this paper a torque vectoring control strategy for an electric vehicle with four in-wheel motors is presented. The control strategy is constituted of a steady-state contribution to enhance vehicle handling performances and a transient contribution to increase vehicle lateral stability during limit manoeuvres. Performances of the control logic are evaluated by means of numerical simulations of open and closed loop manoeuvres. Robustness to friction coefficient changes is analysed.

Optimal Dual-Mode Hybrid Electric Vehicle Powertrain Architecture Design for a Variety of Loading Scenarios

A hybrid-electric vehicle powertrain architecture consists of single or multiple driving modes, i.e., connection arrangements among engine, motors and vehicle output shaft that determine distribution of power. While most architecture development work to date has focused primarily on passenger cars, interest has been growing in exploring architectures for special-purpose vehicles such as vans or trucks for civilian and military applications, whose weights or payloads can vary significantly during operations. Previous findings show that the optimal architecture can be sensitive to vehicle weight. In this paper we investigate architecture design under a distribution of vehicle weights, using a simulation-based design optimization strategy with nested supervisory optimal control and accounting for powertrain complexity. Results show that an architecture under a single load has significant differences and lower fuel efficiency than an architecture designed to work under a variety of loading scenarios.

A New Virtual Coiling Method and its Use in Evaluation of Combining Coiling and Flow-Diversion Treatment in a Patient-Specific Aneurysm

A new realistic finite element method (FEM) based endovascular coil deployment technique was developed to explore the hemodynamic modifications of coiling in addition to flow diverter (FD) treatment. A patient-specific internal carotid artery aneurysm was used as a test case, and a single flow diverter was deployed using a previously developed method [1], along with several coils using the new method. Results showed fluctuations in hemodynamic parameters at low packing densities (1–3 coils) which are unexpected. At high packing density however (6 coils), results were consistent with expectations. These results suggest that adding coils at low packing densities to FD treatment may not cause significant additional flow reduction into the aneurysm sac, but may provide a scaffold for aneurysmal thrombus formation.

Vortex Generation in Two Intracranial Aneurysms

Three-dimensional numerical simulations, using the sharp-interface immersed boundary method, are carried out to investigate the effect of aneurysm shape on the hemodynamics of intracranial aneurysm. In our previous work [1] only a single geometry of an aneurysm was tested, but here two three-dimensional geometries are tested by reconstruction from three-dimensional rotational angiography of a human subject [2]. The results support our previous hypothesis [1], i.e., when the vortex formation time scale at the parent artery is smaller than the transportation time scale across the aneurysm neck, the flow aneurysm dome is dominated by a dynamic, unsteady vortex formation.

Words or Images: Insights on How Engineering Students and Engineers Communicate in Practice

This paper examines the use of language (text and verbal communication) across school and work settings. The participants of the study are from two distinct pools — 380 first-year engineering students and 355 industry professionals. To test the study predictions and interpret the results the individual data sets from both studies were reviewed and analyzed. Data suggests that for the professional engineering population, face to face communication was the preferred communication mode for sharing engineering evaluation, communicating difficult concepts, and describing their work product. Email and file sharing were also utilized communication options, but to a lesser extent. Data from students facing a simulated professional assignment (produce a fabrication instruction for assembling a mechanical object) indicated that 94% of the students’ chose to use language to produce fabrication instructions, compared to only 6% of students who used another tool of engineering representation in the form of sketches. Data investigation and outcomes are discussed in terms of prevalence and importance of language in engineering education.

Automotive Glass Exciter Technology for Acoustic Application

This paper discusses the modeling and analysis of a novel audio subwoofer system for automotive applications using the automobile windshield glass. The use of a piezo-electric actuator coupled with a mechanical amplifier linked to a large glass panel provides a highly efficient method of producing sound. The proposed subwoofer system has the advantage over existing conventional systems of not only reducing the weight of the automobile, but also a significant power savings resulting in an increase of expected fuel economy. Among various design challenges, the glass-sealing design is of huge importance, as it affects the system dynamic response and so the output sound characteristics. The main goal in this manuscript is to evaluate different glass-sealing design configurations by providing a comprehensive Finite Element model of the system. To do so, a comprehensive, yet simplified FE model is developed, and experimental studies are performed in the component level to fine-tune and verify the model. Harmonic response of the system for each sealing configuration design is obtained in the frequency range of 0–200 Hz, and the results are compared and discussed. The finite element model is also beneficial in preliminary design of other components as well as the exciter placement, and predicting the performance of the overall system.