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The objective of this paper is to describe a model for the simulation of the lateral dynamics of a vehicle, specifically buses, under variable trajectory conditions, such as camber and radius of curvature; in addition, a variable speed is added as a simulation parameter. The objective of this study is the prevention of vehicle rollover and sideslip. An 8 degrees of freedom model was developed, considering a front and a rear section of the bus with its respective suspension system, and both sections have been connected by a torsion spring that emulates the torsional stiffness of the vehicle chassis. A Panhard bar is also added at the rear as an additional element to the suspension and the behavior of the bus when it is added is analyzed. This model also allows the evaluation of the force on each suspension component, which allows for future controllability of the active suspension components. The results show the dynamic behavior of the vehicle, and some indicators are introduced to show the possible sideslip or rollover. As a conclusion, the influence of the road parameters on the dynamic behavior of the bus and the effect of the Panhard bar on the dynamic behavior of the bus can be pointed out. [ABSTRACT FROM AUTHOR]

This paper introduces theoretical conditions for the computation of a novel type of state-feedback controller that makes use of Linear Parameter Varying approaches for synthesis. The novelty of this new State-Feedback controller lies on the fact that the controller has a fixed structure with constants matrix gains. However, the controller gains are affine on a parameter dependent basis function, which allows the controller to self-schedule according to real-time changes of the varying parameters. This type of controller is conceived with a focus on implementation, as in contrast with most other LPV approaches. The implementation of this Parameter-Dependent State-Feedback controller does not require any online interpolation or matrix inverse operations, independently of the number of varying parameters. The performance of the proposed approach is validated in a Scaled Autonomous Vehicle for steering control in a path tracking application. [ABSTRACT FROM AUTHOR]

Nanodomains are a biological membrane phenomenon which have a large impact on various cellular processes. They are often analysed by looking at the lateral dynamics of membrane lipids or proteins. The localization of the plasma membrane protein aquaporin-2 in nanodomains has so far been unknown. In this study, we use total internal reflection fluorescence microscopy to image Madin-Darby Canine Kidney (MDCK) cells expressing aquaporin-2 tagged with mEos 3.2. Then, image mean squared displacement (iMSD) approach was used to analyse the diffusion of aquaporin-2, revealing that aquaporin-2 is confined within membrane nanodomains. Using iMSD analysis, we found that the addition of the drug forskolin increases the diffusion of aquaporin-2 within the confined domains, which is in line with previous studies. Finally, we observed an increase in the size of the membrane domains and the extent of trapping of aquaporin-2 after stimulation with forskolin. • Aquaporin-2 diffusion analysis in the plasma membrane in MDCK cells by using Photoactivated Localization Microscopy. • Image mean squared displacement (iMSD) approach revealed that Aquaporin-2 is confined within membrane nanodomains. • Increase in the size of the membrane domains and the extent of trapping of Aquaporin-2 after stimulation with forskolin was observed • iMSD analysis shows Plasma Membrane Diffusion of Aquaporin-2 increases with Forskolin treatment. [ABSTRACT FROM AUTHOR]

Aiming at the difficulty of vehicle lateral control in high-speed condition, a comprehensive control method that integrates active steering (AS) and direct yaw moment control (DYC) systems is proposed for four-wheel independent driving and four-wheel independent steering (4WID/4WIS) vehicle. According to the characteristics of lateral dynamics in high-speed conditions, different principles are adopted in different steering conditions. In a slight or moderate steering, a decoupling control method is proposed, and a penalty function is used to allocate the involvement of AS and DYC for the over-actuated characteristics of 4WID/4WIS vehicle. While in a large steering, based on sideslip phase plane, handling-oriented and stability-oriented control are proposed in order to realise a fine trade-off between handling and stability performance. A transient layer is introduced in the phase plane to further improve the performance of this controller. And the allocation of active yaw moment is also discussed. Simulation results demonstrate that the proposed integrated control method can effectively improve the lateral dynamics performance of the vehicle in high-speed condition as compared to previous control methods. [ABSTRACT FROM AUTHOR]

In order to study the lateral dynamics stability of the levitation module of low- and medium-speed maglev train, the motion equation is simplified by reasonable assumptions, and the simplest lateral dynamics model is established under the premise of retaining the lateral dynamic characteristics of the levitation module. The model can be characterized by a non-autonomous differential equation with periodic coefficients, which can be transformed into a damped Mathieu equation under certain conditions, with its stability equivalent to that of its Poincaré mapping. The stability of the system can be determined by whether the largest modulus of the eigenvalues of the mapped coefficient matrix is > 1. Then, the sensitivity frequency of the vertical electromagnetic force is obtained by calculating the stability domain of the equation in the parameter space. When the variation frequency of the vertical electromagnetic force is approximately equivalent to the sensitivity frequency, the lateral dynamics model is more likely to be unstable. Besides, the variation amplitude and variation frequency of the vertical electromagnetic force, and other factors such as vehicle load and system damping will also change the stability of the lateral dynamics model. However, due to the uncontrollability of these factors, it is necessary to install a lateral damper for the levitation module to improve the lateral stability. [ABSTRACT FROM AUTHOR]

A detailed mathematical analysis of the two-dimensional hybrid model for the lateral dynamics of walking-like mechanical systems (the so-called hybrid inverted pendulum) is presented in this article. The chaotic behavior, when being externally harmonically perturbed, is demonstrated. Two rather exceptional features are analyzed. Firstly, the unperturbed undamped hybrid inverted pendulum behaves inside a certain stability region periodically and its respective frequencies range from zero (close to the boundary of that stability region) to infinity (close to its double support equilibrium). Secondly, the constant lateral forcing less than a certain threshold does not affect the periodic behavior of the hybrid inverted pendulum and preserves its equilibrium at the origin. The latter is due to the hybrid nature of the equilibrium at the origin, which exists only in the Filippov sense. It is actually a trivial example of the so-called pseudo-equilibrium [Kuznetsov et al., 2003]. Nevertheless, such an observation holds only for constant external forcing and even arbitrary small time-varying external forcing may destabilize the origin. As a matter of fact, one can observe many, possibly even infinitely many, distinct chaotic attractors for a single system when the forcing amplitude does not exceed the mentioned threshold. Moreover, some general properties of the hybrid inverted pendulum are characterized through its topological equivalence to the classical pendulum. Extensive numerical experiments demonstrate the chaotic behavior of the harmonically perturbed hybrid inverted pendulum. [ABSTRACT FROM AUTHOR]

While macroscopic models for single or multi-lane traffic flow are well established, these models are not applicable to the dynamics and characteristics of disordered traffic which is characterized by widely different types of vehicles and no lane discipline. We propose a first-order two-dimensional Lighthill–Whitham–Richards (LWR) model for the continuous macroscopic longitudinal and lateral dynamics of this type of traffic flow. The continuity equation is extended into two dimensions and the equation is closed by assuming a longitudinal flow-density relationship as in traditional one-dimensional models while the lateral dynamics is based on boundary repulsion and a desire of a majority of the drivers to go to less dense regions. This is equivalent to Fick's law giving rise to a lateral diffusion term. Using the proposed model, several numerical tests were conducted under different traffic scenarios representing a wide range of traffic conditions. Even for extreme initial conditions, the model's outcome turned out to be plausible and consistent with observed traffic flow dynamics. Moreover, the numerical convergence test is performed using an analytical solution for lateral steady-state conditions. The model was applied for bicycle simulation and reproduced the evolution of lateral density profile with asymmetric behavior. • This study proposed a first-order macroscopic 2D LWR traffic flow model to represent dynamics for disordered traffic. • The continuity equation is extended to two spatial dimensions reflecting the conservation of vehicles in both directions. • To avoid unwanted sharp transitions and shocks in the lateral direction, a lateral diffusion term is added. • The model was tested for different traffic scenarios for both longitudinal and lateral direction. [ABSTRACT FROM AUTHOR]

This paper presents the usage of additional tire information in the form of cornering stiffness to enhance vehicle handling and stability with an adaptive rear-wheel steering control (RWS). The influence of varying cornering stiffness on driving behavior is discussed in advance with a single-track model. On the basis of an enhanced single-track model, a RWS feedforward control is presented with a provided tuning parameter adapting the desired rear axle cornering stiffness for the vehicle. In the following, this paper proposes an adaption law that is derived in order to enhance handling performance and safety of a vehicle, taking into account conflicting goals. Finally, simulation results and driving experiments with the adaptive RWS feedforward control are evaluated in both steady-state and transient conditions. In order to examine the full potential of the approach, the controller is adapted to a wide spreading of the cornering stiffness. Therefore, identified cornering stiffnesses of winter-, summer- and ultra-high performance tires are used as a basis for the adaption. [ABSTRACT FROM AUTHOR]

Risky and aggressive lane changes on highways reduce capacity and increase the risk of collision. We propose a lane-changing pricing scheme as an effective tool to penalize those maneuvers to reduce congestion as a societal goal while aiming for safe driving conditions. In this paper, we first model driver behavior and their payoffs under a game theory framework and find optimal lane-changing strategies for individuals and their peers in multiple pairwise games. Payoffs are estimated for two primary evaluation criteria: efficiency and safety, which are quantified by incorporating driver tradeoffs. After that, the discretionary lane-changing (DLC) model is calibrated and validated by real-world vehicular trajectory data. To manipulate drivers' DLC behaviors, two types of lane-changing tolls based on local-optimal and global-optimal rules are introduced to align individual preferences with social benefits. We find prices can close this gap and achieve 'win-win' results by reducing drivers' aggressive lane changes in the congested traffic. Meanwhile, the tolls collected can be used to compensate drivers who get delayed when yielding, to encourage appropriate yielding behavior and a pseudo-revenue neutral tolling system. • A micro-pricing method penalizing socially-detrimental lane changes is proposed. • Safety vs. efficiency is quantified within the game-theoretic framework. • Two approaches are introduced to engage public-good driving behaviors. • The proposed pricing schemes are tested by microsimulation experiments. [ABSTRACT FROM AUTHOR]

During the composites winding process, running speed, tension fluctuation and other factors often lead to the tape deviation. To improve the winding precision and eliminate the running deviation, lateral dynamics of the tape winding is analyzed and mathematical model of the rectifying system is established. Then, a novel adaptive sliding mode controller (ASMC) is proposed, and principle of this control scheme is employing two fuzzy systems to approximate the nonlinear functions and utilizing another two fuzzy systems to adjust the feedback gain (FG) and switching gain (SG). Stability and convergence of the control system can be guaranteed by the Lyapunov theory and Barbalat Lemma. Simulation and experimental results show that the designed ASMC has highest control precision and much smaller input chattering when compared with other controllers. [ABSTRACT FROM AUTHOR]

This paper presents a high-fidelity, general, and modular method for lateral dynamics simulation of high-speed tracked vehicle. Based on classic terramechanics, a novel nonlinear track terrain model is derived. The track terrain model meets the needs of longitudinal and steering motions, comprehensive track slips, and modular modeling for tracked vehicles with various configurations. The proposed lateral dynamics model is in reasonably agreement with the available experimental data. Using the lateral dynamics model, the main factors (normal pressure distribution, position of gravity center, and ratio of track-ground contact length and tread L / B ) effecting the steady state characteristics of skid steering are discussed. The normal pressure distribution is idealized as trapezoid and dual trapezoid distribution to reflect same common driving situation. The under-steer parameter is introduced in this paper to quantitatively evaluate the steady-state characteristics of skid steering for tracked vehicle. The results show that the ratio of theoretical speed difference and average speed of both side tracks Δ u / u as the steering input is more suitable for the high-speed tracked vehicle. The vehicle with dual trapezoid normal pressure distribution slightly tending to localize in the middle of track or with slightly rearward position of gravity center has better handling stability characteristics. [ABSTRACT FROM AUTHOR]

A mechanics based model to describe the lateral positioning of a thin, tensioned, translating tape over a tilted roller is introduced, based on the assumption that the transport velocity of the tape should match the surface velocity of the roller when there is sufficient traction. It is shown that this condition requires the slope of the neutral axis of the tape and the slope of the centerline of the tilted roller to be the same over the wrapped segment. An extension of this model is discussed including the possibility of circumferential and lateral sliding, depending on the velocity difference between the tape and the roller. The new model is incorporated into a generalized model of a tape path that consists of numerous rollers as well as the appropriate boundary conditions for the take-up and supply reel dynamics. The nonlinear equation of motion is solved numerically, and the steady state solution is found by an implicit time stepping algorithm. An experimental setup with one tilting roller, two or three nearly ideally oriented rollers and two reels is used for verification of the model. The effects of roller tilt angle, tape wrap angle, and the lengths of the free-tape spans upstream and downstream of the tilted roller on the steady state lateral tape position are investigated experimentally and by simulations. The experiments show that the circumferential position of the wrap on the upstream side of a tilted roller has the strongest effect on pushing the tape in the lateral direction. The total wrap angle around the roller has a smaller effect. It was also shown that the tape segments upstream and downstream of the tilted roller interact, and the combined effect results in a different overall lateral tape response in steady state. [ABSTRACT FROM AUTHOR]

A wheel–rail contact formulation for analyzing the nonlinear train–structure interaction that takes into account the wheel and rail geometry is proposed. While most of the existing methods treat the contact forces as external forces, the present formulation uses a finite element to model the behavior in the contact interface, based on Hertz’s theory and Kalker’s laws. The equations of motion are complemented with constraint equations that relate the displacements of the vehicle and structure. This complete system is solved directly using an optimized algorithm. The formulation is validated with experimental data from a test performed on a rolling stock plant. [ABSTRACT FROM AUTHOR]

This paper describes an analytical study of the lateral dynamics of multi-articulated vehicles with multiple axles. A linear planar model of vehicle dynamics is adopted for multiple-axle vehicle combinations with an optional number of trailers. Two tractor and double-trailer combinations are examined for their directional stability and response. Non-oscillatory stability and steering sensitivity in steady-state turning and lane changing are analysed using a stability factor of multiple-axle vehicle combinations. Off-tracking in the steady-state turning of multiple-axle vehicle combinations is also analysed. Numerical calculations for oscillatory stability, steering sensitivity, and off-tracking are presented for multiple-axle vehicle combinations. [ABSTRACT FROM AUTHOR]

The subject of this article is the derivation of a model for lateral dynamics of an endless metal process belt. The minimal configuration of a process belt is a conveyor belt around two cylindrical return drums. In order to ensure a plane surface, the metal belt is pre-stressed to a high level. The main problem of this configuration is to guarantee perfect lateral tracking of the belt utilizing swivelling and tilting drum axes, which should guarantee a constant lateral position of the belt under all process disturbances and geometric imperfections. A dynamic process model in linear state space form is derived from simple geometric parameters of the belt and drums. Measured data from a test rig are utilized to estimate a parametric grey-box model, and both analytical and experimental models are validated against experimental results. The region of validity of the linear models is evaluated and the excellent performance of the grey-box model is demonstrated. The application of this model for control design is demonstrated for compensation of a lateral process force. [ABSTRACT FROM AUTHOR]

In the design and development of high-speed tracked vehicles, it is necessary to have an understanding of the interrelationship between the terrain factors and the vehicle characteristics during steering. The handling behavior of skid-steered tracked vehicles is more complex than that of wheeled vehicles because of non-linear characteristics arising from the sliding interface between the track and the ground. In the present work, a five degree-of-freedom (DOF) steering model of a tracked vehicle is developed, and the handling behavior during non-stationary motion is studied when operating at high and low speeds. It is demonstrated that the inclusion of roll and pitch DOF changes the steering response when compared to the response from three DOF models proposed earlier by several researchers. This is due to the strong coupling between the pitch and yaw motions. The effect of the initial forward velocities on the trajectory of the vehicle during non-stationary motion is also studied. It is observed from the results that the stability is influenced by the type of steering input, steering ratio and vehicle forward speed. [ABSTRACT FROM AUTHOR]

A new creep force model for a dynamic analysis of the wheel/rail tangential force of high-speed railway vehicles has been devised. The test data of actual in-service Shinkansen vehicles at high speed were analysed with the model, and the calculated results verified the validity of the model. The results confirm that the lateral oscillation of the vehicle can be reduced by improving the suspension. By raising the natural frequency of the bogie steer mode to greater than that of the body yawing mode at commercial speed, bogie motions are controlled by the damping equipments and by the mass of the body. The methodology that arranges the natural frequency of vehicle suspension in this manner has been described, and it could be analysed more precisely by the new wheel/rail tangential force model. [ABSTRACT FROM AUTHOR]

In this article, the cornering stiffness estimation problem based on the vehicle bicycle (one-track) model is studied. Both time-domain and frequency-domain-based methods are analyzed, aiming to estimate the effective cornering stiffness, defined as the ratio between the lateral force and the slip angle at the two axles. Several methods based on the bicycle model were developed, each having specific pros/cons related to practical implementations. The developed algorithms were evaluated on the basis of the simulation data from the bicycle model and the CarSimTM software. Finally, selected algorithms were evaluated using experimental data. [ABSTRACT FROM AUTHOR]

A motorcycle towing a single-wheel trailer may provide useful transport for light cargo on narrow tracks and off-road use, particularly in rural areas of developing countries. Four designs of such trailers are described. Linear models are derived for the lateral dynamics of an off-road motorcycle towing this type of trailer straight ahead at constant speed. The trailers were tested behind an instrumented motorcycle. Linear autoregressive models were fitted to the experimental data using system identification techniques. Analytical and experimentally derived models largely agreed on frequency, damping and shape of the weave, wobble and trailer sway normal modes. The trailers made the motorcycle’s steering heavier but the analytical models did not predict this. The location of the articulation axes between the motorcycle and the trailer were found to be critical for stability. The best trailer design handled well with loads up to 200 kg and speeds up to 70 km/h. [ABSTRACT FROM AUTHOR]

The problem of path control of automatically guided vehicles along a desired trajectory is considered where both lateral and longitudinal dynamics have been incorporated in the vehicle model. It is shown that a nonlinear decoupling controller and pole-placement can be used to obtain a closed-loop behavior that is independent of the vehicle operation point. For the pole-placement, the entire state is necessary. Since the sideslip is not available from measurements, an observer is applied, estimating the sideslip. Due to the steady state errors imposed by the nonlinear controller, a predictive filter is used to calculate this steady state error. The effectiveness of this controller is then demonstrated by simulations. [ABSTRACT FROM PUBLISHER]