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The vehicle sideslip angle is an important state of vehicle lateral dynamics and its knowledge is crucial for the successful implementation of advanced driver-assistance systems. Measuring the vehicle sideslip angle on a production vehicle is challenging because of the exorbitant price of a physical sensor. This paper aims to present a novel framework for virtually sensing/estimating the vehicle sideslip angle. The desired level of accuracy for the estimator is to be within +/− 0.2 degree of the actual sideslip angle of the vehicle. This will make the precision of the proposed estimator at par with expensive commercially available sensors used for physically measuring the vehicle sideslip angle.

The proposed estimator uses an adaptive tire model in conjunction with a model-based observer. The performance of the estimator is evaluated through experimental tests on a rear-wheel drive vehicle.

Detailed experimental results show that the developed system can reliably estimate the vehicle sideslip angle during both steady state and transient maneuvers, within the desired accuracy levels.

This paper presents a novel framework for vehicle sideslip angle estimation. The presented framework combines an adaptive tire model, an unscented Kalman filter-based axle force observer and data from tire mounted sensors. Tire model adaptation is achieved by making extensions to the magic formula, by accounting for variations in the tire inflation pressure, load, tread-depth and temperature. Predictions with the adapted tire model were validated by running experiments on the Flat-Trac® machine. The benefits of using an adaptive tire model for sideslip angle estimation are demonstrated through experimental tests. The performance of the observer is satisfactory, in both transient and steady state maneuvers. Future work will focus on measuring tire slip angle and road friction information using tire mounted sensors and using that information to further enhance the robustness of the vehicle sideslip angle observer.

The purpose of this paper is to carry out a series of transient, non‐linear dynamics finite element analyses in order to investigate the interactions between a stereotypical pneumatic tire and sand during off‐road vehicle travel.

The interactions were considered under different combined conditions of the longitudinal and lateral slip as encountered during “brake‐and‐turn” and “drive‐and‐turn” vehicle maneuvers. Different components of the pneumatic tire were modeled using elastic, hyper‐ and visco‐elastic material models (with rebar reinforcements), while sand was modeled using the CU‐ARL sand models developed by Grujicic et al. The analyses were used to obtain functional relations between the wheel vertical load, wheel sinkage, tire deflection, (gross) traction, motion resistance and the (net) drawbar pull. These relations were next combined with Pacejka magic formula for a pneumatic tire/non‐deformable road interaction to construct a tire/sand interaction model suitable for use in multi‐body dynamics analysis of the off‐road vehicle performance.

To rationalize the observed traction and motion resistance relations, a close examination of the distribution of the normal and shear contact stresses within the tire/sand contact patch is carried out and the results were found to be consistent with the experimental counter parts.

The paper offers insights into the interactions between a stereotypical pneumatic tire and sand during off‐road vehicle travel.

The purpose of this paper is to present a study of radial aircraft tire for safety assessment during various scenarios.

A detailed finite element (FE) model of aircraft tire was established based on the actual geometry of the target tire for numerical simulations. As the major component of this tire, rubber material usually presents a complicated mechanical behavior. To obtain the reliable hyperelastic properties of rubber, a series of material tests have been processed. Moreover, in order to validate the proposed model, the simulations results of inflation and static load scenarios were compared with the experimental results. Both of the control volume and corpuscular particle method methods were used in the numerical simulations of aircraft tire.

The comparisons of the two methods exhibit close agreement with the experimental results. To assess the safety of aircraft tire during the landing scenario, the dynamic simulations were processed with different landing weights and vertical landing speeds. According to the relevant airworthiness regulations and technical documents, the tire pressure, deflection and load have been chosen as the safety criteria. Subsequently, the analysis, results and comments have been discussed in detail.

The validated FE model proposed in present study can be effectively used in tire modeling in static and dynamic problems, and also in the design process of aircraft tire.

The aim of this paper is threefold: first, to review the technological state of the art on tire sensor systems; second, to summarize basic methodologies and explore the potential of tire sensing for intelligent vehicle developments and third, to address challenges in the development of tire sensing systems and inspire future research in this field.

Nowadays, automotive industry is moving toward an intelligent and autonomous driving era with the assistance of sensing technology development, whereas tire-road conditions sensing and utilization are of great interest from the point of view of vehicle dynamics control, vehicle safety and vehicle performance evaluation.

Tire sensing is an emerging technology whereby sensor systems are installed on the tire to provide fundamental insights into tire-road interactions for ground vehicles and wheel robots. In the past two decades, tire sensing systems based on various sensor types have been proposed to offer the possibility to investigate tire-road interactions.

Instrumenting the tire with sensors, especially accelerometers and optical sensors, can sense the tire-road interactions and enhance the vehicle performance. The harsh environment inside tire cavity requires reliable, accurate, low weight, modularized and inexpensive sensors. Challenges, such as the data transmission, power management, lack of physics-based tire models need to be solved before the tire sensor becomes commercially viable for production vehicles.

A parallel finite‐element/multi‐body‐dynamics investigation is carried out of the effect of up‐armoring on the off‐road performance of a prototypical high‐mobility multipurpose‐wheeled vehicle (HMMWV). The paper seeks to investigate the up‐armoring effect on the vehicle performance under the following off‐road maneuvers: straight‐line flatland braking; straight‐line off‐angle downhill braking; and sharp left turn.

For each of the above‐mentioned maneuvers, the appropriate vehicle‐performance criteria are identified and the parameters used to quantify these criteria are defined and assessed. The ability of a computationally efficient multi‐body dynamics approach when combined with a detailed model for tire/soil interactions to yield results qualitatively and quantitatively consistent with their computational counterparts obtained using computationally quite costly finite element analyses is assessed.

The computational results obtained clearly reveal the compromises in vehicle off‐road performance caused by the up‐armoring employ to improve vehicle blast and ballistic protection performance/survivability. The results obtained are also analyzed and explained in terms of general field‐test observations in order to judge physical soundness and fidelity of the present computational approaches.

The paper offers insights into the effects of up‐armoring of the HMMWV on off‐road vehicle performance.

This study aims to investigate the influence of surface texture distribution in respect to the procedure of pavement surface wear on friction performance.

The Weierstrass–Mandelbrot (W-M) equation is used to appropriate pavement surface profile. Through this approximation, artificial rough profiles by combining fractal parameters and conventional statistical parameters for different macro-texture are created to simulate the procedure of pavement surface wear. Those artificial profiles are then imported into discrete element model to calculate the interaction forces and friction coefficient between rolling tire and road. Furthermore, wavelet theory is used to decompose the profiles into different scales and explore the correlation between the profiles of each scale and pavement friction.

The influence of tire vertical displacement (TVD) on friction coefficient is greater than fractal dimension of road surface texture. When TVD decreases, the profiles can provide higher friction, but the rolling stability of tire is poor. The optimal fractal dimension of road surface is about 1.5 when considering friction performance. The pavement friction performance improves with wavelength from 0.4 to 6.4mm and decreases with wavelength from 12.8 to 51.2mm.

Artificial fractal curves are generated and analyzed by combining W-M function with traditional parameter, which can also be used to analyze the influence of texture distribution on other pavement performance. The preliminary research provides a potential approach for the evaluation of pavement friction performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0499/

This research aims to present a novel cooperative control architecture designed specifically for roads with variations in height and curvature. The primary objective is to enhance the longitudinal and lateral tracking accuracy of the vehicle.

In addressing the challenges posed by time-varying road information and vehicle dynamics parameters, a combination of model predictive control (MPC) and active disturbance rejection control (ADRC) is employed in this study. A coupled controller based on the authors’ model was developed by utilizing the capabilities of MPC and ADRC. Emphasis is placed on the ramifications of road undulations and changes in curvature concerning control effectiveness. Recognizing these factors as disturbances, measures are taken to offset their influences within the system. Load transfer due to variations in road parameters has been considered and integrated into the design of the authors’ synergistic architecture.

The framework's efficacy is validated through hardware-in-the-loop simulation. Experimental results show that the integrated controller is more robust than conventional MPC and PID controllers. Consequently, the integrated controller improves the vehicle's driving stability and safety.

The proposed coupled control strategy notably enhances vehicle stability and reduces slip concerns. A tailored model is introduced integrating a control strategy based on MPC and ADRC which takes into account vertical and longitudinal force variations and allowing it to effectively cope with complex scenarios and multifaceted constraints problems.

The purpose of this study is to propose a torque vectoring control system for improving the handling stability of distributed drive electric buses under complicated driving conditions. Energy crisis and environment pollution are two key pressing issues faced by mankind. Pure electric buses are recognized as the effective method to solve the problems. Distributed drive electric buses (DDEBs) as an emerging mode of pure electric buses are attracting intense research interests around the world. Compared with the central driven electric buses, DDEB is able to control the driving and braking torque of each wheel individually and accurately to significantly enhance the handling stability. Therefore, the torque vectoring control (TVC) system is proposed to allocate the driving torque among four wheels reasonably to improve the handling stability of DDEBs.

The proposed TVC system is designed based on hierarchical control. The upper layer is direct yaw moment controller based on feedforward and feedback control. The feedforward control algorithm is designed to calculate the desired steady-state yaw moment based on the steering wheel angle and the longitudinal velocity. The feedback control is anti-windup sliding mode control algorithm, which takes the errors between actual and reference yaw rate as the control variables. The lower layer is torque allocation controller, including economical torque allocation control algorithm and optimal torque allocation control algorithm.

The steady static circular test has been carried out to demonstrate the effectiveness and control effort of the proposed TVC system. Compared with the field experiment results of tested bus with TVC system and without TVC system, the slip angle of tested bus with TVC system is much less than without TVC. And the actual yaw rate of tested bus with TVC system is able to track the reference yaw rate completely. The experiment results demonstrate that the TVC system has a remarkable performance in the real practice and improve the handling stability effectively.

In view of the large load transfer, the strong coupling characteristics of tire , the suspension and the steering system during coach corning, the vehicle reference steering characteristics is defined considering vehicle nonlinear characteristics and the feedforward term of torque vectoring control at different steering angles and speeds is designed. Meanwhile, in order to improve the robustness of controller, an anti-integral saturation sliding mode variable structure control algorithm is proposed as the feedback term of torque vectoring control.

Engineered material arresting systems (EMASs) are dedicated to stopping aircraft that overrun the runway before they enter dangerous terrain. The system consists of low-strength foamed concretes. The core component of the arresting system design is a reliable simulation model. Aircraft test verification is required before the practical application of the model. This study aims to propose a simulation model for the arresting system design and conducts serial verification tests.

Six verification tests were conducted using a Boeing 737 aircraft. The aircraft was equipped with an extra inertia navigation system and a strain gauge system to measure its motion and the forces exerted on the landing gears. The heights of the arrestor beds for these tests were either 240 or 310 mm, and the entering speeds of the aircraft ranged from 23.9 to 60.6 knots.

Test results revealed that both the aircraft and the pilots on board were safe after the tests. The maximum transient acceleration experienced by the dummies on board was 2.5 g, which is within the human tolerance. The model exhibited a satisfied accuracy to the field tests, as the calculation errors of the stopping distances were no greater than 7 per cent.

This study proposes a simulation model for the arresting system design and conducts serial verification tests. The model can be used in EMAS design.

An essential part of the validation process of flight simulators has been the comparison of the simulator and aeroplane flight modes of motion for set manoeuvres. A simulator‐to‐flight match is essential for the full range of manoeuvres, both in‐flight and on‐the‐ground, if the simulator is to be used for all usual and unusual scenarios. This is particularly true in ground level manoeuvres where data are not available and pilots need to be trained for situations that are too dangerous to practise in real aircraft and too important to neglect. Aircraft in‐flight modes are used to verify simulator behaviour. However, ground‐contact – an important part of pilot training – modes are not used to verify fidelity. A full systems approach is discussed and a taxonomy of in‐flight and ground‐contact modes provided for the full range of operations, from brakes‐off through taxiing, take‐off, landing and parking. The full taxonomy of modes is needed to ensure that the dynamic behaviour of the simulator is realistic for all in‐flight and ground‐contact scenarios and thereby ensure that the training is realistic for the full range of conventional and dangerous manoeuvres.