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The purpose of this paper is to gain a better understanding of the flow field structure around the race car in two cases: stationary wheel and rotating wheel. In addition, this paper also illustrates and clarifies the influence of wheel rotation on the aerodynamic characteristics around the race car.

The author uses steady Reynolds-Averaged Navier-Stokes (RANS) equations with the Realizable k-ε model to study model open-wheel race car. Two cases are considered, a rotating wheel and stationary wheel.

The results obtained from the study are presented graphically, pressure, velocity distribution, the flow field structure, lift coefficient (C_l) and drag coefficient (C_d) for two cases and the significant influence of rotating case on flow field structure around wheel and aerodynamic characteristics of race car. The decreases in C_d and C_l values in the rotating case for the race car are 16.83 and 13.25 per cent, respectively, when compared to the stationary case.

Understanding the flow field structures and aerodynamic characteristics around the race car in two cases by the steady RANS equations with the Realizable k-ε turbulence model.

Wheel force transducers (WFTs) have performance characteristics that make them attractive for applications in endurance evaluation of road vehicles, ride and handling optimization, tire development and vehicle dynamics. As a WFT is mounted on the the driven wheel, the loads on the wheel and the outputs of WFTs are usually nonlinearly related. Thus, a real-time filter is needed to measure the true loads on the wheel.

In this paper, a new nonlinear filtering algorithm utilizing quadrature Kalman filter (QKF) is proposed to track the actual loads in real time through establishing the specific observation equations with Singer models.

The simulation results show that the accuracy and the rapidity of QKF outperforms the capability of the unscented Kalman filter (UKF). Then, the dynamic tests on the MTS testing platform give the comparisons between the real-time QKF and the wavelet transform, where the former has superior dynamic accuracy. Finally, the practical tests of shifting and braking on a real vehicle confirm the effectiveness of QKF, which further validates the proposed method fitting reality.

In this paper, a newly improved algorithm with QKF for WFT has been proposed and tested experimentally. As the wheel loads are always time-varying and complex, introducing Gaussian noise in the outputs of the transducer, WFT-suitable Singer model and WFT measurement equation base on a QKF are established. The experiment results show that QKF has advanced performance than the traditional UKF. Also, the road wheel test bed produced by MTS has been exploited as the test platform to demonstrate the dynamic efficiency of the proposed real-time filter under various operating conditions for a wide range of loads. And, the practical tests with the real vehicle are accomplished to verify the value and effectiveness of the proposed method.

One of the major shortcomings in the data process of the traditional wheel force transducers (WFTs) is the theoretical errors of initial value determination. A new method to identify the initial values of the WFT for the solution of this problem is proposed in this paper. The paper aims to discuss these issues.

With this method, the initial values can be obtained by equations which are established based on multiple stops on horizontal road.

The calibration and contrast tests on the MTS calibration platform illustrate the better performance with the new method. Moreover, the real vehicle test confirms the effectiveness in practice.

The test results show that the new method of initial calibration has an advanced performance compared to the traditional one. In addition, it is effective in the brake test with a real vehicle.

Two-handed automobile steering at low vehicle speeds may lead to reduced steering ability at large steering wheel angles and shoulder injury at high steering wheel rates (SWRs). As a first step toward solving these problems, this study aims, firstly, to design a surface electromyography (sEMG) controlled steering assistance interface that enables hands-free steering wheel rotation and, secondly, to validate the effect of this rotation on path-following accuracy.

A total of 24 drivers used biceps brachii sEMG signals to control the steering assistance interface at a maximized SWR in three driving simulator scenarios: U-turn, 90º turn and 45º turn. For comparison, the scenarios were repeated with a slower SWR and a game steering wheel in place of the steering assistance interface. The path-following accuracy of the steering assistance interface would be validated if it was at least comparable to that of the game steering wheel.

Overall, the steering assistance interface with a maximized SWR was comparable to a game steering wheel. For the U-turn, 90º turn and 45º turn, the sEMG-based human–machine interface (HMI) had median lateral errors of 0.55, 0.3 and 0.2 m, respectively, whereas the game steering wheel, respectively, had median lateral errors of 0.7, 0.4 and 0.3 m. The higher accuracy of the sEMG-based HMI was statistically significant in the case of the U-turn.

Although production automobiles do not use sEMG-based HMIs, and few studies have proposed sEMG controlled steering, the results of the current study warrant further development of a sEMG-based HMI for an actual automobile.

This paper aims to provide the results of investigations concerning an influence of the tyre with longitudinal grooves on the car body aerodynamics. It is considered as an important aspect affecting the vehicle aerodynamic drag.

To investigate a contribution of grooved tyres to the overall vehicle drag, three wind tunnel experimental campaigns were performed (two by Peugeot Société Anonyme Peugeot Citroen, one at the Lodz University of Technology). In parallel, computational fluid dynamics (CFD) simulations were conducted with the ANSYS CFX software to enable formulation of wider conclusions.

The research shows that optimised tread patterns can be derived on a single tyre via a CFD study in combination with a controlled experiment to deliver designs actively lowering the overall vehicle aerodynamic drag.

A reduction in the aerodynamic drag is one of ways to decrease vehicle fuel consumption. Alternatively, it can be translated into an increase in the maximum travel velocity and the maximum distance driven (key factor in electric vehicles), as well as in a reduction of CO₂ emissions. Finally, it can improve the vehicle driving and steering stability.

The tyre tread pattern analysis on isolated wheels provides an opportunity to cut costs of R&D and could be a step towards isolating aerodynamic properties of tyres, irrespective of the car body on which they are applied.

The purpose of this paper is to present a design of climbing robot with magnetic wheels which can move on the surface of steel bridge. The locomotion concept is based on adapted lightweight magnetic wheel units with relatively high attractive force and friction force.

The robot has the main advantages of being compact (352 × – 215 × – 155 mm), lightweight (2.3 kg without battery) and simple mechanical structure. It is not only able to climb vertical walls and follow circumferential paths, but also able to pass complex obstacles such as bolts, steps, convex and concave corners with almost any inclination regarding gravity. By using a servo as a compliant joint, the wheel base can be changed to enable the robot to overcome convex corners.

The experiment results show that the climbing robot has a good performance on locomotion, and it is successful in negotiating the complex obstacles. On the other hand, the limitations in locomotion of the robot are also presented.

Compared with the past researches, the robot shows good performance on overcoming complex obstacles such as concave corners, convex corners, bolts and steps on the steel bridge. Magnetic wheel with the characterization of compact size and lightweight is able to provide bigger adhesion force and friction coefficient.

The purpose of this paper is to develop an electronic solution to effectively lock swivelling wheel steering positions to driver‐control. Simple and affordable systems are described to assist forklift users in steering their walkie type forklifts or pallet jacks across sloping ground.

A rolling road was created as an assessment tool and trials with both the test bed and in real situations were conducted to evaluate the new systems. The small swivel detector that was created could be successfully attached to swivelling wheel swivel bearings.

The new system was successful, robust and was not affected by changeable parameters. The simple systems assisted hand truck operators in steering their forklifts across sloping ground without veering off course. The systems overcame the problems associated with forklifts that steer using two swivelling wheels and meant that less work was required from hand truck operators as their forklifts tended to travel in the desired direction

Experiments demonstrated that calibrating forklift controllers for straight‐line balance and optimizing motor‐compensation did not solve this problem. Instead, swivelling wheel angle was selected to provide feedback. At the point when veer is first detected, a forklift has already begun to alter course and the job of the correction system is to minimize this drift from the desired course.

The forklifts and pallet jacks often steer by having swivelling wheels but problems with this configuration occur when a forklift is driven along sloping ground because they can swivel in the direction of the slope. Gravity then causes the forklift or pallet jack to start an unwanted turn or “veer” and the vehicle goes in an unintended direction. This situation is exacerbated for vehicles with switch controls, as switches cannot provide fine control to trim and compensate.

Each year in the United States, over 100 employees are killed and 36,000 are seriously injured in accidents involving forklift trucks and pallet carriers. This is the second leading cause of occupational fatalities in “industrial” type workplaces. The research aims to make the use of this type of equipment safer and the systems can be attached to many standard forklifts and pallet jacks.

The first touchdown moment of aircraft tyres on a runway is the critical phase where maximum of the vertical and horizontal ground loads is produced. Some valuable drop tests have been performed at Langley research centre to simulate the touchdown and the spin-up dynamics. However, a long impact basin and a huge power source to accelerate and decelerate the landing gear mechanism have been used. Based on a centrifugal mechanism, the purpose of this paper is to propose the conceptual design of a new experimental setup to simulate the spin-up dynamics.

A schematic view of the proposed mechanism is presented, and its components are introduced. Operating condition of the system and the test procedure are discussed in detail. Finally, tyre spin-up dynamics of Boeing 747 is considered as a case study, and operating condition of the system and the related test parameters are extracted.

It is shown that the aircraft tyre spin-up dynamics can be simulated in a limited laboratory space with low energy consumption. The proposed setup enables the approach velocity, sink rate and vertical ground load to be adjusted by low power actuators. Hence, the proposed mechanism can be used to simulate the tyre spin-up dynamics of different types of aircraft.

It is important to note that more details of the setup, including the braking and actuating mechanisms together with their control procedures, should be clarified in practice. In addition, the curved path introduced as the runway will cause errors in the results. Hence, a compromise should be made between the tyre pressure, path curvature, the induced error and the cost of the experimental setup.

The proposed experimental setup could be constructed in a limited space and at a relatively low cost. Low power actuators are used in the proposed system. Hence, in addition to the performance tests, fatigue tests of the landing gear mechanism will also be possible.

Based on a centrifugal mechanism, the conceptual design of a new experimental setup is presented for simulating the tyre spin-up dynamics of aircraft. Considering that the drag load developed during tyre spin-up following initial touchdown is an important factor governing the design of the landing gear mechanism and aircraft structure, the authors hope this paper encourages engineers to continuously make efforts to increase the transparency of the touchdown process, enabling optimisation of landing gear design.