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In the design of a path-tracking controller for autonomous vehicles, mediating the conflicting objectives among path-tracking, vehicle stabilisation, and low computational cost is a challenging iss...

The success of NASA's Mars missions has generated a renewed interest in planetary exploration, along with a need for better mobility of wheeled mobile robots (WMRs)—steering performance, in particular, has not yet reached an acceptable benchmark in high-precision models. This study focuses on the steering mechanics of WMRs, as it can enrich the terramechanics of planetary rovers. An improved sinkage model based on the variable sinkage exponent is proposed, and the sinkage exponent is derived as a function of steering angle. Furthermore, a high-precision steering moment model is proposed based on the steering-sinkage model, which considers the interaction area and the lug effect. The model can fit the results obtained by all of the experimental wheels, based on soil parameter identification. Most of the max relative errors (MREs) for the sinkage are within 5%, and the coefficients of determination are more than 0.97. The MREs of moment increase with increasing vertical load but remain within 10%. This technique can also be applied to other WMRs with rigid wheels steering on deformable terrain.

The advent of New Generation Large Aircraft (NGLA), such as the Boeing 747 and Airbus A380, has introduced more complicated landing gears and heavier axle loads. The wheel configurations and loads induce complex mechanical response to the pavement structure particularly during turning movements while taxiing. The objective of this paper is to determine the lateral force on all wheels during turning movements to permit future field measurements and pavement design. The paper documents the use of the velocity instantaneous method to analyse the lateral forces imparted by a B747 and A380 under a moving aircraft. Firstly a multi-wheel landing gear is represented by a single wheel, and then the total lateral force of each landing gear at different velocities is analysed, and the total lateral force of a multi-wheel gear is assigned to each wheel. The results show that both taxiing velocity and nose gear steering angle have an effect on the lateral force during turning at low speed, and an increase in v...

Rollover warning system predicts whether the vehicle has a risk of rollover in a period of time based on the current driving state of the vehicle. Most previous studies on rollover evaluation index have only used vehicle’s current states and often ignored the judgment of the overall tendency of the motion. In the calculation of the rollover early warning algorithm, it is assumed that the vehicle input was known. Based on the above reasons, this paper introduces the derivative of LTR into the rollover index, using an improved predictive LTR (IPLTR) as the rollover index, and realized the real-time calculation through an 8-DOF nonlinear vehicle model. The vehicle rollover prediction system is achieved through the preview driver model and the rollover prediction index calculation model. To achieve a proper preview time for the driver model, a comprehensive evaluation formula that considers the trajectory deviation, the steering wheel rotation speed and lateral acceleration is used. Finally, an IPLTR is developed, which utilizes a driver model to predict the steering angle and several other sensor signals available from the electronic stability control system as inputs. The new IPLTR index can provide a time-advanced measure of rollover propensity and its effectiveness is verified by virtual tests and experimental test data. Simulation results by double lane change (DLC) and “Highway Merge” road maneuvers show that the proposed rollover warning algorithm is rather satisfying. Experimental test by pylon course slalom maneuver also proves its effectiveness and has more advantages of such a system in rollover prevention.

An increasing number of underwater gliders have been applied to lake monitoring. Lakes have a limited vertical space. Therefore, good space-saving capacity is required for underwater gliders to enlarge the spacing between monitoring waypoints. This paper presents a space-saving steering method under a small pitch angle (SPA) for appearance-fixed underwater gliders. Steering under an SPA increases the steering angle in per unit vertical space. An amended hydrodynamic model for both small and large attack angles is presented to help analyze the steering process. Analysis is conducted to find the optimal parameters of net buoyancy and roll angle for steering under an SPA. A lake trial with a prototype tiny underwater glider (TUG) is conducted to inspect the applicability of the presented model. The trial results show that steering under an SPA saves vertical space, unlike that under a large pitch angle. Simulation results of steering are consistent with the trial results. In addition, multiple-waypoint trial shows that monitoring with steering under an SPA covers a larger horizontal displacement than that without steering.

In this paper, we proposed a magnetically steerable guidewire device composed of two parts: steering part and feeding part. The steering part consists of a magnet attached to the end of a commercial guidewire and 2-pair Helmholtz coils, and the feeding part consists of a motorized stage and a device for holding the guidewire. In detail, the 2-pair Helmholtz coils generate a uniform magnetic field that can align the guidewire magnet in the region of interest (ROI) along a desired direction. In addition, the feeding part remotely controls guidewire insertion and the length of the flexible part of the guidewire extruded from a catheter. For accurate alignment at the end of the guidewire, we controlled the flexible length of the guidewire extruded from a catheter and the intensity and direction of the uniform magnetic field using the feed-forward method. In addition, to reduce alignment error due to unpredicted disturbances and friction effects between the test-bed and the guidewire, proportional-integralderivative control is introduced as a feedback control algorithm. Using the control algorithms, we demonstrated accurate actuation of the steerable guidewire device with a steering angle error of less than 0:5◦. We expect that the proposed steerable guidewire device can be applied to the development of a 3-D locomotive guidewire with position recognition for percutaneous coronary intervention (PCI).

This paper presents an adaptive neural network (NN) nonlinear observer to estimate the longitudinal tyre forces as well as the lateral speed which is not measured on standard vehicles. The proposed adaptive neural network (NN) observer uses the longitudinal speed, yaw rate and the steering angle dynamics of the vehicle as measured states. It is used to estimate the states, and the longitudinal tyre forces, which are unknown dynamics, with high performance. The obtained simulation results show the effectiveness of the proposed neural network nonlinear observer.

In this paper, a new rear steering angle control strategy is developed. This strategy is derived from the nonlinear 3DOF bicycle model to improve three-wheeler stability and manoeuvrability. Howeve...

This article will present the results of comparative tests of the functionality of new type of a universal steering wheel, intended to use as HMI to drive a so-called ECO car by both disabled and ablebodied people. The already mentioned ECO car would be characterized, among other things, by electric drive and “steer by wire” system (which is of particular importance in designing adaptive human-vehicle interface). The car was designed as part of the “Eco-Mobility” project implemented under the Innovative Economy Operational Programme co-financed from European Regional Development Fund. The prototype of the car and some of its functions were demonstrated on the “eco-mobilnosc” website [4, 2]. An able-bodied person is sitting in a driver’s seat (in the car’s equipment), while the disabled person can drive the car sitting in their own wheelchair. The functionality feature of the steering wheel which is distinctive from the classic steering system (classic steering wheel + pedals) is the opportunity to drive the vehicle using only hands (without using legs). The steering wheel developed as part of the ECO Mobility project is part of a system that allows a disabled person to use a car completely on their own (without any help from others). The same car can also be used by able-bodied people hence the notion of its “universality”. ECO steering wheel is essentially adapted to drive cars with Steerby-wire system [13, 6]. This solution makes it possible to program the steering angle corresponding to the maximum steering angle of the front wheels. There is a possibility to adjust the so-called melt steering ratio (obviously not while driving). In these studies, there were two different combinations included: 180o to 35o and 120o to 35o. These changes are intended to limit the angle of rotation of the steering Maciej KozlowSKi

An autonomous vehicle control algorithm based on Ackerman Geometry is known to be reliable in low tire slip situation. However, vehicles at high speed make lateral errors due to high tire slip. In this paper, considering the tire slip of vehicles, the steering angle is determined based on the Ackerman Geometry and is supplemented tire slip angle by the Stanley steering algorithm. In addition, to prevent the tire slip, the algorithm, which restricts steering if a certain level of slip occurs, is used to reduce the lateral error. While many studies have been extended to include vehicle slip, studies also need to be carried out on the tire slip depending on hardware performance. The control algorithm of autonomous vehicles is compensated considering the sensor noise and the performance of steering actuator. Through the various simulations, it was found that the performance of steering actuator was the key factor affecting the performance of autonomous driving. Also, it was verified that the usefulness of steering algorithm considering the tire slip and performance of steering actuator.

In this paper, we studied the steering performance of wheelset with primary suspension characteristics of railway vehicle. We carry out dynamic analysis and experimental study for the vehicle models which are different primary suspension characteristics. The steering angle of a vehicle model (Case 1) operating in domestic subway lines is insufficient compared with an objective steering angle for curved track. And the steering angle of a vehicle model (Case 2) with improved self-steering performance of wheelset is a little improved compare to previous vehicle model. But also Case 2 model is still insufficient compared with an objective steering angle and has its limit in steering performance. So to overcome this limit of steering performance of passive type railway vehicle, an active steering technology is being developed. In case of vehicle model with active steering system, the steering performance is improved remarkably compared to passive type vehicle model.

Recently, novice driver or weak drivers was difficult to understand the movement characteristics of the carand are immature sense of width and length of the car according to various each driver’s sex and age, model. Tocomplement this problem, the use of rear sensor and the camera is increased. And the parking assistance system thatimproves the convenience of parking the driver is being developed. Accordingly, parking guide system is needed toreflect the difference in the steering angle and correct the error distance.In this study, it is proposed that the turning radius during backward by complementing the existing Ackerman Jentaudtype. And it develops more accurate parking guideline to be able to generat algorithm by applying the formula to propose a steering wheel angle sensor value derived through the handle. Key Words : Ackerman jeantaud type, Calibration, CAN, Parking system * Corresponding Author : Seon-Bong Lee(Keimyung Univ.)Tel: +82-10-5180-5067 email: seonbong@kmu.ac.krReceived January 20, 2015Accepted May 7, 2015Revised February 13, 2015Published May 31, 2015

In this paper, a range-free, passive, and autonomous underwater vehicle (AUV)-based localization scheme is proposed for underwater acoustic sensor networks. The AUV has used four directional acoustic beams with fixed steering angle and width, which led to the constant ratio of array size to wavelength, in order to localize the sensor nodes. The AUV was moved on a random waypoint path and broadcasted messages periodically. The sensor nodes used two successively received message sequences which were submitted by two beams on one side of the AUV path in order to localize themselves. Extensive simulation results in MATLAB demonstrated that using the proposed localization scheme could yield better localization success than other AUV-based localization methods.

International audience; This paper presents automatic parallel parking for a passenger vehicle, with highlights on a path-planning method and on experimental results. The path-planning method consists of two parts. First, the kinematic model of the vehicle, with corresponding geometry, is used to create a path to park the vehicle in one or more maneuvers if the spot is very narrow. This path is constituted of circle arcs. Second, this path is transformed into a continuous-curvature path using clothoid curves. To execute the generated path, control inputs for steering angle and longitudinal velocity depending on the traveled distance are generated. Therefore, the traveled distance and the vehicle pose during a parking maneuver are estimated. Finally, the parking performance is tested on a prototype vehicle.

Ducted-type underwater robot that we developed has streamlined outer shape with duct inside, so that it can have low fluid resistance and because of short body length, it has highly good motion performance like short turning radius. Ducted type underwater robot that we developed had made as concept with rudder inside the duct. But for enlarge the turning force, it must have larger space and our robot has no margin for that. For this situation, we re-designed as the rudder on the outside of the duct. On this design, rudder can be affected from outside flow of body of robot and also there are some differences between combinations of steering angles. Therefore, in this paper we studied about the combinations of angles of rudders that have optimal steering angle when the robot only has inside flow of duct.

This paper discusses a new method of estimating vehicle lateral stability region, which is an important way to describe the vehicle safe or stable lateral operation capability. Benefited from the introduced local linearization method, a realistic 2D LuGre tire model can be applied to describe the coupled and nonlinear longitudinal and lateral friction forces for the stability region estimation. Compared with the estimation results from a classic phase portrait method, which does not distinguish vehicle and tire stabilities, the obtained vehicle lateral stability regions are more conservative by successfully considering vehicle and tire stability together. Simulation results discuss the variations and trends of the estimated stability regions with respect to different main parameters, such as the vehicle longitudinal velocity, tire-road friction coefficient, and steering angle.

A steering aid system called active steering is evaluated by simulating different kinds of driving events. The main purpose of the steering system is to allow the driver control the vehicle independently. A full car vehicle model is simulated in Matlab/Simulink with 14 degree of freedom of equations which include the ride vehicle model and also the handling model. The steering angle is the input of the vehicle model that should be focused on. The angle of the steering system between the tires when turning the vehicle is taken in consideration. Simulations are made on different road conditions effect and also side wind disturbances. Different values are applied to the simulation to reduce the effect of the driving events. Therefore, these simulations results to provide a better improvement to the steering system. The aim for this work is to validate the vehicle response with an instrumented experiemental vehicle. Specific driving events in these simulations are the road adhesions and lateral side wind disturbances.

Steering system directly determines the tractor steering characteristics. It has great influence on the driving comfort of a tractor and the life of the tire, etc. Based on the platform of the virtual prototype software ADAMS, the virtual prototype model of tractor steering system and the motion simulation were established. The parameters such as the tractor steering angle displacement were measured and the steering performance of tractor was analyzed. The model and simulation method this article used has significant references on the performance analysis of other vehicle steering system.

Localization is a criticalissue for autonomous vehicle navigation. A localization model based on thestable response in lateral dynamics of the vehicle is hard for practicalapplication because of its nonlinearity, multidimensionality and multivariable.A dynamic self - adaptive network, which is able to adjust the scale of theparameters dynamically and has a good regression performance and self learningability, is used as a approximator to modeling the localization of the vehicle.In order to get a higher accuracy in modeling, a Kalman filer is designed forthe input signal such as steering angle and velocity. From the practicaltesting results on our vehicle, it’s indicated that the localization error is less than 1meter. So, the proposed method in this paper is a practicable and efficient onefor application.

Multi-view three-dimensional (3D) display using beam steering optical array is proposed. For the beam steering optics we fabricated an electrowetting micro prism array. The steering angle and the profiles are measured. Based on the results, we modeled the beam steering devices and simulate the performance for 3D display. Realistic view profiles are obtained by integrating the experimental beam profile data. Below the crosstalk 200%, the distance between views is 3 mm and the number of views is 90, which shows the possibility of the quasi continuous viewpoint with high resolution 3D display.

Vessel collision prevention issue has always been the focus of the nautical science research. This paper considers a variety of factors that affect the safety of the ship collision avoidance to optimize the research on multi-boat collision avoidance magnitude, by using the improved collision risk index model and simulated annealing particle swarm optimization. The result of the simulation indicates that SAPSO can deal with the problems of angle of avoiding collision, results are accurate and feasible.

In this study, the detecting device of the steering angle is designed based on the single-chip microcomputer of STC12LE5A60S2 and the wireless communication module of ZICM2410; the hardware structure design and software implementation of the device are proposed. With this detecting device the steering angle can be detected any time which can be shown on the LCD board of the detecting device, and on main controller through the wireless communication; the rules can be modified in the condition of zero drift to ensure a continuous trouble-free operation with high degree of accuracy; the performance detection index is the evidence to judge whether the car is qualified or not. Less cost, greater reliability, flexibility and convenience are the main features of this device.

This paper discovers the dynamic modeling process based on equilibrium condition of forces and moments, in order to improve handling stability, the side-slip angle need to be reduced to zero, special process is used in the dynamic equations simplification for demanded theoretical steering angle of each axel. At last this systems steady-resonance characteristics are researched.

The steering stability of a vehicle at high speed is the urgent key problem to be solved of automobile independent development. And it is also the premise and one of the necessary conditions of vehicle safety. Considering of the effects of tire nonlinearity, a 4-DOF dynamics model for a vehicle is established. The yaw rate responses, side slip angle, carriage roll angle and front wheel steering angle with different vehicle speeds are calculated. The calculated values are then compared with the values without considering of the effects of tire nonlinearity. The simulations results show that the vehicle responses can be reflected accurately by using nonlinear tire model. With the bigger vehicle speed, the effects of tire nonlinearity on vehicle high-speed steering stability become more obvious.

In this letter, we present a new approach to beam-steering of short, ultrawideband (UWB) pulses using a single-feed radiating structure. Utilizing a radiator consisting of small apertures backed by a reverberating cavity, a time-reversal technique is applied to generate a short pulse at each aperture with the corresponding time delay for beamforming at a desired steering angle. In the process, we also employ a novel method to improve beamforming performance. This approach offers significantly simpler beamforming and steering of short pulses compared to conventional methods, which typically require a complex multifeed structure. Moreover, beam-steering of high-power short pulses is achievable using this approach with a suitable choice of feed.

The paper gives an analysis of a variable-geometry suspension system. Since the system also affects both the wheel camber angle and the additional steering angle, the coordination of steering and wheel tilting can be handled by this system. Since the nonlinear effects of the system are significant, the paper gives a detailed set-based analysis for the possibilities and constrains. A nonlinear polynomial SOS (Sum-of-Squares) programming method is applied to present the advantages of the variable-geometry suspension system.

Nowadays, a concept of tilting three-wheel vehicle is introduced, one of which is the electric tilting tricycle to provide an alternative mode of transportation. Some of the tilting tricycle design usinga tadpole trike configuration and it needs an adequate steering system that can be synergized with tilting mechanism. The steering mechanism follows the Ackermann steering geometry. Usage of Ackermann geometry means applying a mechanism of trapezoidal four-bar linkage to the tricycle. To create and maintain the simple trapezoid shape, Triple Ball Tie-rod model, a single rod which supports three ball joints, is proposed. Since the capabilities of the model are yet to be proven, this research evaluates the usageof a tie-rod model to find out its capabilities to support the works of the steering mechanism of the tricycle. The measurements are conducted after the simulation of the 3D model to extract some data such as maximum lean angle and inner and outer steering angles. Another simulation using regular tie-rod model also conducted with the same method for comparison purposes. The results of the study are maximum allowed tilting angle and generated Ackermann steering angles. Each designed models have their respectiveadvantages.

A control method is proposed to improve vehicle yaw stability by the integrated control of yaw moment control. The control strategy using feedback compensator is proposed, which produces direct yaw moment and front steering angle to control yaw rate, by actively controlling the front steering angle, the integrated control system makes the performance of the actual vehicle model follow that of an ideal vehicle model. A experiment is performed at different conditions, the results showed the presented method can effectively control the yaw rate, and at the same time lighten the burden of the driver. Key words: EPS; Yaw rate feedback; Vehicle stability

We introduce a research on steering dampers using MR fluid (Magnetorheological Fluid). In recent years, steering dampers have been used in on-road and off-road motorcycles. Steering dampers stabilize the front end of motorcycles. The advantage of a steering damper is increased stability, but hydraulic steering dampers give rise to the problem of 'Heavy Steering'. In order to resolve this heavy steering, we need to set the restrictions on the maximum damping force and avoid it from interfering when the rider is steering. However only reducing the damping force will lead to insufficient damping force when the handle, unresponsive because of kickback, shakes. We solved this problem with the development of an electric control damper which generates sufficient damping force at low steering angle rates and also allows for mechanically limiting the maximum damping force. The damper design uses "Direct Shear Mode" and features a steering angle sensor built into the damper, which results in easier and smoother steering. To test its effectiveness, we installed our new steering damper and asked for feedback from riders. From the received feedback, we were able to confirm the effectiveness and efficiency of our new design as well as its superiority over other traditional designs. In particular, we were able to improve stability when entering a corner or riding over gaps by generating more damping force from a low steering angle rate in comparison to traditional dampers. We also succeeded in keeping the nimble handling while riding by reducing the maximum damping force. Language: en

It is studied that a great proportion of traffic problems lies in vehicles’ steering system, and the maximum steering angle decides their steering capability and their minimum turning radius. The measuring principle of rapid measuring system, and the automatic tracking principle of measurement system have been analyzed in the paper. Also, the infrared tracking, the measuring plate positioning, the calculation of minimum turning radius, and the processing method of the test results have been described in detail. It is proved that the automatic automobile steering angle detecting system has reached the general requirements both in detection resolution and the measuring accuracy.

This study proposes a method for real-time identification of a driver model. The proposed method requires only the yaw rate sensor, the steering angle sensor, and velocity sensors that are usually installed in the production car. The identification algorithm involves the division of the recorded data, prefiltering of the divided data, estimation of the driver's desired response, and identification. The prefilter extracts the driver's involuntary response that can be modelled in a simple form. The ideal car response that the driver attempts to track is estimated from the recorded data, and this response is provided to the identification algorithm of the feedback driver model for error tracking. These newly developed methods enable real-time identification under actual driving conditions. The driving simulator experiments and the actual driving tests were performed, and the proposed method was validated. The results show that the time history of the variation in the driver's characteristics can be realised in real time using the proposed method. © 2013 Copyright Taylor and Francis Group, LLC.

This paper put forward a struction model of pneumatic beam transport trailer of principal and subordinated vehicle model with combination of four-wheel steering and articulated frame. Its steering conditions are analyzed. The steering condition and the method of determining of the minimum turning radius and the calculation formula of turning radius are obtained.

It mentions not only the testing mechanism, but also the system’s mechanical structure and the detailed methods of hardware and software of the according testing equipment. It comparatively covers the whole studying and developing process of the system. Advanced technology, such as, computer, electronics, sensors and air-pressure driving method are adopted in the system, which not only realize automatic tracking, accurate positioning and fast testing, but also makes it possible to be low in cost, easy to be handled, as well as its high accuracy and powerful net performance.

Stability, in particular in outdoor sloped conditions, is one of the most important requirements for design safe and effective future mobile robotic platforms. In this work, the authors’ recent results on the study and development of an articulated mobile robot for agricultural and forestry activities in hilly/mountain environments are presented. First of all, a dynamic model for the stability analysis of a generic articulated platform has been designed and implemented. Then, different practical working conditions have been simulated to assess the stability of the system; possible stabilizing actions when travelling on a sloped surface on the steering angle, velocity and central joint have been finally evaluated and discussed.

Driver cognitive distraction (e.g., voice-based IVISs) has become an important and growing safety concern. Cognitive distraction detection presents an important function for driver distraction mitigation systems. We present a new approach to analyze the difference of correlation between eye movement and steering angle to detect the state of cognitive distraction. Meanwhile, we design a secondary task to simulate cognitive distraction in simulated driving. In the end, experimental analysis shows that the variances and mean value of GMA analysis results between eye movement and steering angel vary between different drivers, but the trend of the difference between cognitive distraction driving and normal driving is consistent. Their difference is enough to detect cognitive distraction.

This paper presents an adaptive sliding mode (ASM) controller designed for a vehicle Steer-by-Wire (SbW) system. First, the SbW system is modeled as a second-order system from the steering motor input voltage to the front wheel steering angle. For simplicity, the tire-to-ground frictions and the self-aligning torque are treated as external disturbances acting on the SbW system. Next, an ASM controller is designed for the SbW system, which utilizes sliding mode control to handle the parametric uncertainties and an adaptive estimation scheme to estimate the coefficient of the self-aligning torque, respectively. Finally, experiments are carried out to validate the performance of the ASM control. The experimental results indicate that the proposed ASM controller possesses strong robustness and high tracking accuracy.

The yaw rate signal is of great significance for vehicle stability and motion control systems. However, contamination of sensor signal may sometimes be involved for various reasons. Although the sensor is well tuned before using, loss of ground may introduce a bias to the sensor signal during vehicle operation. To reconstruct the yaw rate signal and estimate the yaw rate sensor bias, a linear parameter-varying (LPV) approach for an electric vehicle is proposed in this paper, which requires signals of vehicle longitudinal velocity, contaminated yaw rate, and steering angle as the inputs. The H∞ performance from the modeling error to the estimation errors is taken as the design objective in the development of this LPV observer. The time-varying parameter, which is the vehicle longitudinal velocity here, is tackled by the LPV approach. Vehicle experimental investigations are conducted to show the effectiveness of the observer in estimating the sensor bias and reconstructing the yaw rate signal.

Vehicle dynamics plant phenomena during acceleration, deceleration and curve turning in uncertainty ground road is very complexity and nonlinearity model. No integrated chassis control by various systems have been proposed to control vehicle behavior by distributing front-rear and left-right braking/ABS & driving/TCS forces, adjusting rear-wheel steering angle/4WS. ABS and TCS can reduce the slip and skid factor that improve the braking and driving performance but cannot eliminate the vehicle sideslip (VSS). In other side four wheel steering (4WS) have good performance in reducing of vehicle sideslip to improve maneuver ability but fail in decreasing of stopping distance (SD) and increasing driving performance (DP). In this research, to solve the previous problem, author purpose an integrated ABS-TCS-4WS control using mamdani-fuzzy logic. Input and output variable are described. Steering maneuver, slope of the road, vehicle mass (number of passenger) are the input variables, while error of wheel slip fact...

In this study, the results of a steady-state cornering test using a sport-touring motorcycle and the analysis of those test results are presented. This test was conducted as an activity in our efforts to realise a quantitative development method for motorcycles. The measurement data from this test include measurement results for tyre force, tyre moment, and tyre slip angle that have not been practically addressed in the research of motorcycles, in addition to normal measurement results for velocity, steering angle, steering torque, roll angle, etc. Until now research on motorcycle dynamics characteristics has indicated that ‘there is a strong relationship between the motorcycle dynamics characteristics and the tyre slip angle’. However, since it is difficult to take highly precise measurements of the motorcycle’s tyre slip angle during actual riding, especially when the motorcycle is tilted during cornering, such measurements have been avoided, cf. [H. Ishii and Y. Tezuka, Considerations of turning perfor...

This paper presents two methods for estimating the ground vehicle hand-wheel steering signals and for detecting the voltage-to-angle conversion and hand-wheel steering sensor faults. An enhanced input observer is used to estimate the actual hand-wheel steering angular signal and a sliding mode approach is utilized to improve the robustness of the method with respect to the parametric uncertainties associated with actual vehicle operations. The performance and effectiveness of the proposed hand-wheel steering angle estimator and diagnosis methods are shown by experimental results obtained on a ground vehicle equipped with a single incremental, low-cost, angular steering sensor.

In this paper, active disturbance rejection control method is used to implement the steering angle following control of steer-by-wire system for the simplification of controller designing. The dynamic model of steering performing system is established, and then a second order active disturbance rejection controller is designed to control the steering angle. On the electric vehicle with steer-by-wire system, the angle following test of steering performing system is carried out under the control of the second order active disturbance rejection controller. The results show that the designed active disturbance rejection controller can restrain the effect of system resistant force on the accuracy of angle following and meet the requirement of steer-by-wire system to the steering angle following function. At the same time, there isn’t necessary to get the accurate data of steering system and the design process of controller becomes simple with adopting active disturbance rejection control method.

A driver-assistance system (DAS) that combines an automatic road departure avoidance (RDA) system with the driver's steering input is presented. The system is based on a closed-loop driver decision estimator (DDE), which establishes the risk of road departure. If a road departure is likely to occur, the RDA system intervenes by correcting the steering angle. Robustness is guaranteed by an Hinf controller designed to take into consideration the main uncertainties affecting the dynamics. Driver-in-the-loop tests evaluate the performance of the system in terms of robustness, risk of road departure, and driving experience. Experiments show that the system is effective in reducing the risk of road departure without impeding maneuverability.

International audience; Road bank angle plays a crucial role on the vehicle lateral dynamics; unfortunately, this parameter is not measured by low cost sensor. For this reason, we present in this paper a virtual sensor to estimate the road bank and vehicle roll angles. This virtual sensor is based on a proportional-integral observer introduced by \cite{Koenig06}. This observer uses a simple lateral vehicle model which offers a better approximation of the vehicle's dynamic behavior under moderate driving situations. Moreover, the estimation process uses some measurements like sideslip angle, roll rate, yaw rate and steering angle. Notice that in this study the road bank angle is considered as an unknown input. An important part of this work is devoted to the experimental validation of the PI observer. This validation gives an appropriate estimation of the vehicle roll and road bank angles, these results show the ability of this observer to estimate simultaneously the road attributes and vehicle dynamics parameters.

Steering angle features prominently in accident and driver behavior analysis or other applications, but can hardly be recorded in most monitoring devices such as vehicle traveling data recorder. According to vehicle kinematics model, this paper proposes a solution for steering angle determining based on longitudinal velocity and lateral acceleration signals. Simulation and experiments have been conducted to prove the method feasibility and reliability. Furthermore, trajectory reconstruction is demonstrated as one of the many applications of the steering angle estimation.

Handling and stabilities is important for steer by wire (SBW) system. Firstly, a platform for SBW handling and stabilities analysis and parameter optimization with friendly graphic user interface (GUI) is built based on Matlab GUI technology. Secondly, three degree of freedom handling and stabilities model with steering angle as input is built and system stability is analyzed based on Routh-Hurwitz stability and poles methods. Then simulations are carried out to show effects of some vehicle parameters on handling and stabilities. Finally, the handling and stabilities sensitive parameters are optimized using genetic algorithm method to improve step responses and handling and stabilities.

For automated guidance control of a magnetically guided-all wheel steered vehicle, it is necessary to have information about position and orientation of the vehicle, and deviations from the reference path in real time. The magnet reference system considered here consists of three magnetic sensors mounted on the vehicle and magnetic markers, which are non-equidistantly buried in the road. This paper presents an observer to estimate such position and orientation at the center of gravity of the vehicle. This algorithm is based on the simple kinematic model of vehicle and uses the data of wheel velocity, steering angle, and the discrete measurements of marker positions. Since this algorithm requires the exact values of initial states, we have also proposed an algorithm of determining the initial position and orientation from the 16 successive magnet pole data, which are given by the magnetic measurement system(MMS). The proposed algorithm is capable of continuing to estimate for the case that the magnetic sensor fail to measure up to three successive magnets. It is shown through experimental data that the proposed algorithm works well within permissible error range.

In this article, a multi-input multi-output (MIMO) robust road departure avoidance system based on a closed-loop driver decision estimator (DDE) is presented. The main idea is that of incorporating the driver intent in the control of the vehicle. The driver decision estimator computes the vehicle look ahead lateral position based on driver input and uses this position to establish the risk of road departure. The MIMO controller uses the vehicle lateral position at the look ahead distance and yaw rate to calculate both the front steering angle and differential braking as the control efforts. The DDE ensures that the vehicle remains within the road borders without altering the vehicle response when the driver steers the vehicle back. It is shown that the use of both active steering and differential braking can stabilize the vehicle with shorter look ahead distances compared to the use of only steering. Numerical simulations show the effectiveness and robustness of the proposed approach in comparison with the generalization of other available methods.

This paper deals with the lateral dynamic model of an all-wheel steered articulated vehicle to design a guidance controller. Nonlinear dynamic model of articulated vehicle is developed by complementing the model about the BRT system of California PATH in U. S. A. and the Phileas system of the APTS in Netherlands. Linear lateral dynamic model has been derived from the nonlinear dynamic model under some assumptions associated with the driving conditions. To design a guidance controller, we derive a transfer function that is steering angle as input and lateral acceleration as output from the linear lateral dynamic model by applying the parameter of vehicle that is developed by Korea Railroad Research Institute. To validate the dynamic model, nonlinear dynamic model has been compared with a vehicle model that has been programmed in ADAMS, and linear dynamic model has been compared with a nonlinear dynamic model under sime assumptions.