Development and Simulation-based Testing of a 5G-Connected Intersection AEB System

In Europe, 20% of road crashes occur at intersections. In recent years, evolving communication technologies are making V2V and V2I faster and more reliable; with such advancements, these crashes, as well as their economic cost, can be partially reduced. In this work, we concentrate on straight path intersection collisions. Connectivity-based algorithms relying on 5G technology and smart sensors are presented and compared to a commercial radar AEB logic in order to evaluate performances and effectiveness in collision avoidance or mitigation. The aforementioned novel safety systems are tested in a blind intersection and low adherence scenario. The first algorithm proposed is obtained by incorporating connectivity information to the original control scheme, while the second algorithm proposed is a novel control logic fully capable of utilizing also adherence estimation provided by smart sensors. Test results show an improvement in terms of safety for both the architecture and high prospects for future developments

Optimal Design and Control of 4-IWD Electric Vehicles based on a 14-DOF Vehicle Model

A 4-independent wheel driving (4-IWD) electric vehicle has distinctive advantages with both enhanced dynamic and energy efficiency performances since this configuration provides more flexibilities from both the design and control aspects. However, it is difficult to achieve the optimal performances of a 4-IWD electric vehicle with conventional design and control approaches. This work is dedicated to investigating the vehicular optimal design and control approaches, with a 4-IWD electric race car aiming at minimizing the lap time on a given circuit as a case study. A 14-DOF vehicle model that can fully evaluate the influences of the unsprung mass is developed based on Lagrangian dynamics. The 14-DOF vehicle model implemented with the reprogrammed Magic Formula tire model and a time-efficient suspension model supports metric operations and parallel computing, which can dramatically improve the computational efficiency. The optimal design and control problems with design parameters of the motor, transmission, mass center, anti-roll bar and the suspension of the race car are successively formulated. The formulated problems are subsequently solved by directly transcribing the original problems into large scale nonlinear optimization problems based on trapezoidal approach. The influences of the mounting positions of the propulsion system, the mass and inertia of the unsprung masses, the anti-roll bars and suspensions on the lap time are analyzed and compared quantitatively. Some interesting findings that are different from the `already known facts' are presented

Windbreaks for railway lines: Wind tunnel experimental tests

A number of tests were carried out in the Politecnico di Milano wind tunnel to study the properties of different windbreak barriers for high-speed railway lines. A possible problem with the wind tunnel testing of these devices is the need to create wide scenarios (long barriers) and achieve high Reynolds number values in order to avoid scaling problems. In this study, two experimental campaigns were performed. In the first stage, the Reynolds number sensitivity was checked through specific tests in a high-speed test section (Remax= 7 × 105): it was found that, in the presence of barriers, the rolling moment coefficient is independent of the Reynolds number. A second experimental campaign was then carried out in a low-speed test section (Remax= 1.3 × 105) where a very long scenario was reproduced (150 m at real scale): barriers of different types, heights and porosities were tested. To compare them, forces and pressures on the vehicle model as well as forces on the barrier were measured

Connected and Automated Vehicles: Integrating Engineering and Ethics

This book reports on theoretical and practical analyses of the ethical challenges connected to driving automation. It also aims at discussing issues that have arisen from the European Commission 2020 report “Ethics of Connected and Automated Vehicles. Recommendations on Road Safety, Privacy, Fairness, Explainability and Responsibility”. Gathering contributions by philosophers, social scientists, mechanical engineers, and UI designers, the book discusses key ethical concerns relating to responsibility and personal autonomy, privacy, safety, and cybersecurity, as well as explainability and human-machine interaction. On the one hand, it examines these issues from a theoretical, normative point of view. On the other hand, it proposes practical strategies to face the most urgent ethical problems, showing how the integration of ethics and technology can be achieved through design practices. All in all, this book fosters a multidisciplinary approach where philosophy, ethics, and engineering are integrated, rather than just juxtaposed. It is meant to inform and inspire an audience of philosophers of technology, ethicists, engineers, developers, manufacturers, and regulators, among other interested readers

Predictive Display with Perspective Projection of Surroundings in Vehicle Teleoperation to Account Time-delays

Teleoperation provides human operator sophisticated perceptual and cognitive skills into an over the network control loop. It gives hope of addressing some challenges related to vehicular autonomy which is based on artificial intelligence by providing a backup plan. Variable network time delays in data transmission is the major problem in teleoperating a vehicle. On 4G network, variability of these delays is high. Due to this, both video streaming and driving commands encounter variable time delay. This paper presents an approach of providing the human operator a forecast video stream which replicates future perspective of vehicle field of view accounting the delay present in the network. Regarding the image transformation, perspective projection technique is combined with correction given by smith predictor in the control loop. This image transformation accounts current time delay and tries to address both issues, time delays as well as its variability. For experiment sake, only frontward field of view is forecast. Performance is evaluated by performing online vehicle teleoperation on street edge case maneuvers and later comparing the path deviation with and without perspective projection

Heavy-Vehicle Response to Crosswind: Evaluation of Driver Reactions Using a Dynamic Driving Simulator

Heavy vehicles exiting (or entering) a tunnel at high speed under a strong crosswind is a particularly critical condition since the aerodynamic load changes drastically, greatly affecting the lateral stability of the vehicle. Often, active control systems (active suspensions, active front steering, etc.) and infrastructure elements (e.g., wind fences) are proposed to reduce the induced risks. To help the design of these devices, the present paper investigates the response of the vehicle–driver system in the case of a high-sided lorry exiting a tunnel under crosswind, by using Driver-In-the-Loop simulations. The study was performed using the dynamic driving simulator of Politecnico di Milano and 28 test drivers. Vehicle and aerodynamic models have been developed to reproduce the phenomenon in a highly immersive environment. During the tests, several combinations of vehicle and wind speed were considered. The effect of vehicle loading condition (Empty and Laden) was also investigated. The performed tests allowed us to gain information about the sequence of the driver’s actions and associated delays, which may induce lane deviation or, in the worst case, rollover. It was found that lane invasion may happen for ratios of lateral aerodynamic force over vehicle weight force bigger than 0.1, while rollover could happen for ratios bigger than 0.3. Moreover, it was found that the driver’s response typically happens with a delay of ∼0.25 s with respect to the onset of the crosswind stimulus

A Torque Vectoring Control for Enhancing Vehicle Performance in Drifting

When dealing with electric vehicles, different powertrain layouts can be exploited. Among them, the most interesting one in terms of vehicle lateral dynamics is represented by the one with independent electric motors: two or four electric motors. This allows torque-vectoring control strategies to be applied for increasing vehicle lateral performance and stability. In this paper, a novel control strategy based on torque-vectoring is used to design a drifting control that helps the driver in controlling the vehicle in such a condition. Drift is a particular cornering condition in which high values of sideslip angle are obtained and maintained during the turn. The controller is applied to a rear-wheel drive race car prototype with two independent electric motors on the rear axle. The controller relies only on lateral acceleration, yaw rate, and vehicle speed measurement. This makes it independent from state estimators, which can affect its performance and robustness. Document type: Articl