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Driving dynamics performance is one of the key customer attributes to be developed during product development. In the vehicle development process, freezing the hardware of the chassis aggregates is one of the major priorities to kick off the other vehicle development activities. The current work involves the development of a multilink suspension for an SUV class vehicle. Typically, each OEM performs several product development loops for maturing the vehicle design. The driving dynamics performance evaluation and tuning happens on a physical vehicle with the driver in Loop. Tuning of suspension parameter on the physical vehicle entails actual replacement of parts/components. This encompasses multiple tuning cycles in product development associated with increased cost and test time. To reduce the product development time and cost while delivering first time right chassis configuration, we took an approach of getting driver-in-loop through driving simulator in the concept phase.

In automotive world role of suspension system is to absorb vibrations from the road, and to provide stability while vehicle is going over bumps or uneven roads, cornering, acceleration and braking etc. For body on frame SUVs which are typically characterized by high center of gravity, it is quite critical to find best balance in ensuring stability of the vehicle and having comfortable ride performance. Rigid axle rear suspension is quite a typical choice in such vehicles, wherein lower and upper control links are two important components subjected to lateral, longitudinal, and vertical loads. These links allow the vehicle to move smoothly throughout the entire range of suspension travel. Kinematics and compliance optimization of these links is a major factor in definition of ride-handling performance of the vehicle.

For any two wheeler vehicle development, rider and pillion comfort while driving the vehicles over different kinds of road perturbations holds high importance. Designing a vehicle for comfort starts at the very beginning of its layout definition through vehicle geometric parameters, key hardpoints, mass-inertia distribution of subsystems and suspension characteristics. There is a need for highly reliable simulation models for comfort predictions as any change in layout during subsequent design stages is a very costly affair. Accurately predicting comfort using a full vehicle model is a challenging task though as it depends on how realistic the Simulation Model is to that of actual vehicle. While suspension stiffness and damping characteristics remain critical parameters for the comfort, selection of tyres are known to hold equal importance in vehicle comfort.

Potholes are a major cause of discomfort for riders and vehicle damage. The passive suspension systems which are used in the passenger vehicles are primarily reaction based. These can’t adapt to the changing road conditions which means the best ride quality and handling characteristics cannot be ensured for different driving situations. Passive suspension system also needs more maintenance due to its inability to reduce the impact of the road irregularities. In recent years, semi-active suspension systems have been developed to improve ride comfort and vehicle safety. This paper covers the integration of a semi-active suspension system with a road preview mechanism with a TATA car model to investigate its impact on ride comfort, handling characteristics and component loads in digital domain. A quarter car vehicle model is used to compare different active damping control strategies.

Heavy Commercial Road Vehicles (HCRVs) may be more susceptible to rollover incidents due to their higher centre of gravity position than passenger vehicles, and rollover is one of the significant causes of HCRV accidents. Therefore, variation in vehicle roll behaviour becomes crucial to the safety of an HCRV. Toe misalignment is a commonly observed phenomenon in HCRVs, and studying its impact on roll behaviour is important. In this study, the impact of the symmetric toe and thrust misalignment on the roll behaviour of an HCRV is analysed using IPG TruckMaker®, a vehicle dynamics simulation software. A ramp steer manoeuvre was used for the simulations, and the toe misalignment on a wheel was chosen from the range [-0.21°, 0.21°]. Variation in roll behaviour was quantified using the steering wheel angle at which one-wheel lift-off (OWL) occurred (SWAL).

Automated parking systems for cars have become the need of the hour globally, gaining wide acceptance from customers, and hence OEMs are working towards achieving precise/accurate automated parking. Various algorithms are being developed to plan the trajectory of the vehicle to be moved in/out of the desired parking slot. Most of these algorithms assume a static environment and don’t account for highly dynamic objects. Accounting for such objects is vital especially when autonomously exiting a parking slot and merging with traffic. This paper summarizes our initial efforts in addressing dynamic objects, specifically the ‘right of way’ aspects, while autonomously exiting a parking slot. In this study, we propose a novel approach for generating linear and angular velocity profiles using Deep Reinforcement Learning (DRL) in conjunction with Hybrid A* path planning for autonomous vehicles (AVs) navigating parking maneuvers.

Vehicle design necessarily involves tuning various parameters to optimize automotive performance metrics like ride and handling. The tuning process is iterative and involves a trial-and-error approach to understand the influence of the input parameters on various output metrics. We develop tuning models and run many simulations to optimize various parameters, followed by validation. This process is computationally expensive and contingent on the output metrics. Alternatively, data-driven modelling could overcome shortcomings but requires extensive data sets to train, which may not be feasible in the initial design phase. In this work, we demonstrate how we can use Dynamic Mode Decomposition, commonly used in Fluid Mechanics, to create Reduced Order Single Parameter Tuning Models, which are computationally lightweight and can provide the output metrics as a function of one tuning parameter. It reduces the tuning time and also helps to understand the system better.

Motorcycles are a preferred means of transportation in most of the countries due to its economic factor and ease in travelling. Rider comfort is an important aspect while designing a vehicle. Rider comfort is often compromised by unwanted vibrations experienced at human interface points also called as tactile points. These unwanted vibrations also affect rider’s motorcycle control and overall health. There are two major source of vibrations in a motorcycle that is engine & road inputs. In current study, a method is being explored to predict engine induced vibrations. Engine induced vibrations at various locations are simulated through multi body dynamics (MBD) and finite element (FE) simulation methods at vehicle level. Motorcycle model comprising of engine, frame and subassemblies are modeled in FE tool and then condensed to be used in MBD tool. Piston assembly, connecting rod, bearings and engine mounts are modeled in MBD tool.

With the advancement of automotive industries, the need for wireless connectivity between vehicle and smartphone is increasing. To meet the demand for wireless connectivity, Bluetooth plays a vital role. Testing Bluetooth systems is challenging and complex when development cycles of the system involve multiple partners. The system under test must fulfil consumers expectation of Bluetooth functionality paired with their personal devices. Despite many advances and existence of a few reliable systems, hardware limitation, and lack of standardization in Bluetooth test system are some of the prolonged issues. Throughout the course, various capabilities and existing traditional Bluetooth testing system practice were researched, which majorly at a system level (Black box). The gap of such testing is the escape of defect which involves the interoperability of multiple profiles like AVRCP, HFP, and A2DP.

The Indian automotive industry is striving towards more safe and durable vehicles. A need was felt to study the effect of changes in axle static loads on fatigue life of the axle components. Also, there was a need to develop generic test method, as there are no test standards or generic methods available in public domain for fatigue testing of commercial vehicle axles. The study was carried out to check direct effect of change in axle loads on various connections on axle, effect of suspension configuration and force distribution, Vehicle dynamics, etc. In this paper, an India specific generic load spectra was evaluated for accelerated laboratory validation. Paper discusses the methodology as; study of heavy commercial vehicle systems, road load data collection on identified test vehicles w.r.t. test matrix finalized, India specific test loads and load spectra development, normalization of axle load spectra w.r.t to static axle weights and arriving at test guidelines.

Tyre wear is of significant concern for the automotive industry due to multiple reasons including vehicle performance, safety, economy, environmental (particulate matter emission) aspects, etc. Therefore, ensuring enhanced tyre tread wear resistance is one of the most important criteria while developing a new tyre. Tyre wear phenomenon is influenced by various factors, such as road conditions, driving habits, maintenance practices and tyre design parameters (construction, geometry and material). The wear assessment through the classical field-testing approach consumes significant time and resources. Therefore, digital predictive tools are very useful in predicting wear characteristics at the early stage of the tyre development process. In this study, an attempt has been made to capture the impact of tread geometry, tread material, vehicle geometry, vehicle speed, test track geometry, etc. on tyre wear.

With the recent development in virtual modelling and vehicle simulation technology, many OEM’s worldwide are using digital road profiles in virtual environment for vehicle durability load prediction and virtual design evaluation. For precise simulation results, it is important to have the tire digital twin which is the realistic representation of tire in the virtual environment. The study comprises of discussion about different types of tire models such as empirical, solid model, rigid ring model and flexural ring models such as Pacejka, MF Swift, CD tire, F tire etc. and also the complexity involved in development of these tire models. Generation of virtual tire model requires highly sophisticated test rigs as well as vehicle level testing with Wheel Force transducers and other vehicle dynamics sensors. The large number of data points generated with testing are converted in standard TYDEX format to be further processed in various software tool for virtual model generation.

Bimetal composite pipe has higher strength and is more corrosion and high temperature resistant compared to single metal pipe, making it a new type of pipe that is being gradually applied to important industrial fields such as aviation and aerospace manufacturing. To study the hydraulic forming mechanism of bimetal composite pipes, the forming process is divided into three stages: liner pipe elastic–plastic deformation, base pipe loading, and unloading. The stress and strain relation between the liner and base pipe during the gradual increase in hydraulic pressure is analyzed, and the range of selected internal pressure required for composite pipe formation and the relation between residual contact pressure and internal pressure for the liner–base pipe interface are obtained.

With the increased use of devices requiring the Internet of Things (IoT) to enable “New Mobility,” the demand for satellite-enabled IoT is growing steadily, owing to the extensive coverage provided by satellites (over existing ground-based infrastructure). Satellite-based IoT provides precise and real-time vehicle location and tracking services, large-scale geographical vehicle and/or infrastructure monitoring, and increased coverage for remote locations where it may not be possible to install ground-based solutions. The Application of Satellite-based Internet of Things for New Mobility discusses satellite-based IoT topics that still need addressing, which can be broadly classifieds into two areas: (1) affordable technology and (2) network connectivity and data management. While recent innovations are driving down the cost of satellite-based IoT, it remains relatively expensive, and widespread adoption is still not as high as terrestrial, ground-based systems.

While computational resources are in accelerated development, so are virtual models of physical systems applied to engineering analysis via simulation. In this context, the present work aims to develop and update software that uses a computational model of a half-car into a full vehicle with a driver with 8 degrees of freedom for vehicle dynamics analysis. The Vehicle Dynamic Model software provides four main results: (I) Steady-state responses; (II) frequency responses; (III) animation of the vehicle riding on the track profile; and (IV) the natural frequencies and vibration modes of the vehicle. Seeking an interactive process that allows simulations aiming at a clear understanding of the effects on the dynamic behavior of a passenger vehicle according to the defined design parameters, a friendly graphical user interface was also developed with the aid of MATLAB.

The Brake Pull phenomena is the directional deviation when a strong deceleration is applied, this happens due to asymmetries in the vehicle with diverse origins: dimensional, stiffness, damping, friction and loading condition. This phenomenon creates the necessity of driver inputs on the steering wheel adjusting the vehicle direction to keep the straight line. Great part of asymmetries in the vehicle is avoidable due to building quality, correct maintenance, and others. However, an unequal loading condition on the transversal direction of the vehicle is very common: the vehicle occupied only by the driver is a usual condition. This circumstance creates a load asymmetry that can induces the brake pull phenomena. This study aims to create and validate a virtual toll capable of representing the brake pull phenomena caused by a loading asymmetry.

The commercial aviation currently accounts for roughly 2.5 % of the global CO2 emissions and around 3.5% of world warming emissions, taking into account non CO2 effects on the climate. Its has grown faster in recent decades than the other transport modes (road, rail or shipping), with an average rate of 2.3%/year from 1990 to 2019, prior to the pandemic. Moreover, its share of Greenhouse (GHG) emissions is supposed to grow, with the increasing demand scenario of air trips worldwide. This scenario might threaten the decarbonization targets assumed by the aviation industry, in line with the world efforts to minimize the climate effects caused by the carbon emissions. In this context, hydrogen is set as a promising alternative to the traditional jet fuel, due to its zero carbon emissions.

Virtual simulation is a fundamental tool for the development of new vehicles, both for individual components and for complete subsystems and full vehicles. Many software tools exist in the automotive sector to assess full-vehicle behavior and performance, including multibody software and algorithms based on 14 (or more) degrees-of-freedom vehicle dynamics models. In order to reproduce the testing maneuvers and typical vehicle mission, a key part of such simulation tools is the virtual driver algorithm. It is essential to implement a control logic that reproduces the handling response of the driver, so that the closed-loop maneuvers can be evaluated. However, the response of typical virtual drivers is not always similar to the human driving characteristics. Virtual driver algorithms can perform very fast, precise, and smooth steering and pedal actions, while humans display a more variable, delayed and often not optimal actions.

Unguided sounding rockets, also known as sub-orbital rockets, are vehicles that carry scientific experiments and/or sensors to collect data during their trajectory. These rockets lack active control but are capable of traversing the Earth’s atmosphere. It is crucial to thoroughly analyze the flight parameters during the preliminary design phase. The Open Rocket flight simulation software, developed by Sampo Niskanen, is a widely used open-source project. However, it has some simplifications in comparison to its documentation. It does not specify the calculations of critical parameters required for the rocket’s stability during its flight. Additionally, it does not calculate data related to dynamic stability, which encompasses the system’s ability to make disturbances corrections during the rocket’s trajectory. Consequently, this study presents a flight simulation of a rocket with 6 degrees of freedom using Matlab/Simulink.

The traditional centralized random access (RA) and data transmission (DT) protocol used to transmit small-sized packets suffers from high signaling overhead and low channel utilization. To cope with that, this paper proposes a novel distributed queuing random access and data transmission protocol based on multiple-input multiple-output (MIMO) technology for intelligent aircraft scenarios. In the RA phase, the collided, successful, and idle states are redefined according to the degree of freedom (DOF) in MIMO to utilize the RA channel effectively. In the DT phase, the optimal number of simultaneously transmitted M2M devices in the data queue is derived by the number of base station’s antennas to enhance throughput and reduce signaling. Results reveal that the proposed protocol can not only improve the efficiency of RA but also increase the throughput and reduce the delay of DT with the aid of DoF in MIMO while reducing the signaling overhead.