Anti-roll Research Articles

Potential of natural fiber based polymeric composites for cleaner automotive component production -a comprehensive review

Automotive industries have l been trying to shift towards cellulosic based composites because of their properties like high modulus, high strength, ease of modification, less pollution, light weight, etc,. These natural/cellulosic fibers are abundantly available in nature in the form agricultural wastes, for example sugarcane bagasse, cotton linter, rice husk, etc,. Natural fibers are now widely used in industries other than automobile due to the above stated advantages. The main impediments of using natural fibers are, 1) thermal stability, 2) compatibility issues and moderate interfacial interaction etc,. This review investigates the potential of cellulosic fiber based polymeric composites for automotive application. In particular, this review focuses on the effects of incorporating natural/cellulosic fibers on the performance of automotive body, anti-roll bar, bumper, leaf Spring, helical spring and gears. Another focus area for this paper was an extensive review on its best applications in the automotive sector, detailed information about the type of fiber and their use in the specific automotive sector is tabulated. It was found that cellulosic/natural fiber based polymeric composites can be an efficient alternative for man-made synthetic fibers in the automotive sectors.

Establishing a novel adaptive fuzzy control algorithm for an active stabilizer bar with complex automotive dynamics model

Rollovers can cause many hazards to the passengers in the car. The main cause of this problem is the driver's sudden steering at high speed to avoid an obstacle or enter a roundabout. To limit this phenomenon, it is necessary to equip the car with an active stabilizer bar. In this article, we use a new fuzzy control method to direct an active stabilizer bar. This method is established based on five points of view regarding the stability and responsiveness of the system, so it is called the novel adaptive fuzzy algorithm (NAFC). This is a completely new point in the article compared to previous studies. A combined dynamics model that is a fusion of the seven DOFs spatial dynamics model and the three DOFs motion model. The simulation and calculation occur in the Simulink® interface, with two cases representing the steering angles J-turn and Fish-hook. The speed of the car is changed according to three specific values. According to the calculation results, the vehicle body roll angle is greatly reduced when using active stabilizer bars controlled by the novel adaptive fuzzy algorithm. Besides, the minimum dynamic force value at the rear wheel is better guaranteed. The car's roll index is also sharply reduced when applying this algorithm to the hydraulic stabilizer bar model. In addition, rollover occurs when the car steers the J-turn at v3 and the fish hook at v2 and v3 (if stabilizer bars are unavailable). Meanwhile, car’s stability is always guaranteed in the case of a car with a stabilizer bar using the NAFC algorithm. The article's achievements can be used as a basis for developing more complex control algorithms in the future.

Enhancing the lateral stability of the vehicle by using a fuzzy algorithm to control the active stabilizer bar

This article studies the instability of automobiles when steering at high speeds. In this article, the model of spatial dynamics is used to simulate vehicle oscillation. Besides, the model of nonlinear double-track dynamics is also combined to determine the effects of the wheel when steering. To limit the instability when steering, the hydraulic stabilizer bar is suggested. The performance of the system depends on the previously designed controller. The FLC algorithm with two inputs is used to control the operation of the system. The membership function and fuzzy rules are determined based on the designer’s experience. The simulation is performed by MATLAB software with three specific steering cases. In each case, the speed of the vehicle will be increased gradually. The results of the article show that the value of the roll angle is greatest in the third case, corresponding to the speed of v3 = 100 (km/h). If the vehicle does not have a stabilizer bar, the vehicle can roll over at any time. In contrast, when the active stabilizer bar was combined with the proposed FLC algorithm, the vehicle’s stability was significantly improved. The vehicle’s roll angle and the difference in vertical force at the wheels were also significantly reduced when using this algorithm for the stabilizer bar model. This result should be further verified through the experimental process.

Design and Analysis of Anti-Roll Bar in Formula Vehicle

Abstract: This study explains a coherent flow for designing, analyzing, and testing a tuneable anti-roll bar system for a formula student race-car. The design process starts with the analytical calculation for roll stiffness using constraining parameters such as CG (Centre of Gravity) height, total mass, and weight distribution in conjunction with suspension geometry. Then, the material selection for the design i.e., Aluminium 7075 T6 is made based on parameters such as density and modulus of rigidity. A MATLAB program is used to iterate defection vs load for different stiffness and shaft diameter values. This is then checked with kinematic defection values in FUSION 360s geometry. To validate with the material defection, finite element analysis is performed on ANSYS workbench. Manufacturing accuracy for the job is checked using both static analysis in lab settings and using sensors on vehicles during ontrack testing. The error percentage is found to be 4% between the target stiffness and the one obtained from static testing. Parameters such as moment arm length, shaft diameter and length, and defection were determined and validated. This paper shows the importance of an anti-roll bar device to tune the roll stiffness of the car without interfering with the ride stiffness.

Dynamic Modeling and Analysis of a Driving Passenger Vehicle

This study presents a dynamic model of a passenger vehicle and analyzes its dynamic characteristics and responses. A dynamic vehicle model with seven degrees of freedom was established to analyze the behavior of a driving vehicle. The vehicle model had three degrees of freedom for the sprung mass’s motion and four degrees for the unsprung masses. For this model, the equations of motion were derived using Lagrange’s equation. To verify the model, the suspension deformations computed using the model were compared with those measured through three actual vehicle driving tests: the slalom, double lane change, and step steer tests. Furthermore, we investigated the effects of suspension stiffness, suspension damping, and anti-roll bar torsional stiffness on the dynamic characteristics and responses of the vehicle model. This study presented a new full-car model that can analyze a turning vehicle’s behavior in response to changes in the steering angle input. The developed dynamic vehicle model may help vehicle designers predict the dynamic responses of a vehicle through simulation without performing a driving test.

Dynamics performance of long combination vehicles with active control systems

A state-of-the-art review of the dynamics of long combination vehicles (LCVs) is provided. The performance-based standards (PBS) that are commonly used globally are reviewed, including those in Canada and Australia. The discussions include the low-speed and high-speed longitudinal, lateral, and yaw performance of LCVs, which in many respects are different than the conventional tractor-semitrailers. The low-speed discussions include the vehicle startability, gradeability, acceleration, and offtracking. The high-speed considerations include rollover dynamics, braking distance and time, overtaking, down-grade holding, and ride quality. Some of the latest development in actively controlled (intelligent) systems to improve LCVs’ dynamic performance is emphasised, such as hill-start assist (HAS), roll stability control (RSC), electronic stability control (ESC), electrified dolly (e-dolly), active trailer steering (ATS), active braking, slip control (SC), active trailer differential braking (ATDB), active and semi-active antiroll bars, and active and semi-active suspensions. The study concludes that although great progress has been made during the past two decades for integrating advanced, intelligent, electromechanical systems in LCVs, much more work remains to address some of the future environmental and performance demands, particularly considering the integration of electrical and alternative-fuel propulsion systems in heavy commercial vehicles.

Active Optimal Roll Control of Railway Vehicles in Curved Tracks Using an Electrically Actuated Anti-roll Bar System

Active Optimal Roll Control of Railway Vehicles in Curved Tracks Using an Electrically Actuated Anti-roll Bar System

Using a novel fuzzy 3-inputs algorithms to control the active hydraulic stabilizer bar with the complex model of the vehicle nonlinear dynamics.

Under the influence of centrifugal force, the rollover phenomenon may occur. The vehicle rolls over when the wheel is completely separated from the road surface, i.e., the vertical force of the wheel is reduced to zero. To overcome this problem, the active stabilizer bar is used at the front and rear axles of the vehicle. The active stabilizer bar works on the difference in fluid pressure inside the hydraulic motor. This article is aimed at studying the vehicle rollover dynamics when the hydraulic stabilizer bar is used. In this article, the model of a complex dynamic is established. This is a combination of the model of spatial dynamics, the model of nonlinear double-track dynamics, and the nonlinear tire model. The operation of the hydraulic actuator is controlled by a fuzzy algorithm with 3-inputs. The defuzzification rule is determined based on the combination of 27 cases. The process of calculation and simulation is done with four specific cases corresponding to steering angles. In each case, three situations were investigated. Besides, the speed of the vehicle is also gradually increased from v1 to v4. As a result of the simulation, which was performed in the MATLAB-Simulink environment, the output values such as roll angle, change of the vertical force, and roll index were significantly reduced when the active stabilizer bar was used. If the vehicle does not use the stabilizer bar, the vehicle may roll over in both the second, third, and fourth cases. If the vehicle uses a mechanical stabilizer bar, this also occurs in the third and fourth cases (only at a very high velocity, v4). However, the rollover phenomenon did not occur if the vehicle used a hydraulic stabilizer bar controlled by the fuzzy 3-inputs algorithm. In all investigated cases, the stability and safety of the vehicle are always guaranteed. Besides, the responsiveness of the controller is also very good. An experimental process needs to be conducted to verify the correctness of this research.

Study and analysis of structural steel sway bar using linear and nonlinear regression techniques

The primary goal of this project is to determine the effect of varying sway bar stiffness and the stress generated when the clamping distance of the anti-roll bar is changed. A sway bar effect on the rear suspension can only be detrimental to vehicle handling. To ensure a vehicle's desired handling characteristics, these installations should be tested under severe cornering conditions. The analysis has been done by using Beta CAE ANSA, MSC NASTRAN, and Beta CAE METAPOST software applications for generative structure analysis. This analysis is done on the basis of constant displacement but in the opposite direction since the main motive of the sway bar is achieved by twisting it. After gathering the engineering data, the prediction of bushing distance for the respective stiffness of the bar is calculated using a linear regression technique. In this study, observe the stiffness behaviour with respect to bushing position and predict the bushing distance for a target stiffness using a linear regression table.

Hydraulic Integrated Interconnected Regenerative Suspension: Sensitivity Analysis and Parameter Optimization

Hydraulic integrated interconnected regenerative suspension (HIIRS) is a novel suspension system that can simultaneously harvest the vibration energy in the suspension and enhance the vehicle dynamics. The parameter sensitivity of the HIIRS system is analyzed and the significant parameters are optimized in this paper. Specifically, a half-vehicle model with the HIIRS is established. Based on the model, the parameter sensitivity of the hydraulic system is analyzed with three objectives, ride comfort, road holding, and average energy harvesting power. The parameters considered in this study are more abundant than those in previous related studies, including hydraulic cylinder inner diameter, hydraulic motor displacement, resistance, initial system pressure, and accumulator parameters. It turns out that the most sensitive parameters are the inner diameter of the hydraulic cylinder, the resistance, and the displacement of the hydraulic motor. To further study the performances that the HIIRS could present, both the single-objective optimization and the multi-objective optimization problems are solved and compared with the optimized traditional suspensions. The optimized HIIRS performs better in ride comfort and road holding than the optimized traditional suspension and anti-roll bar suspension. Different from the previous suspension optimization design, multi-objective optimization not only considers the traditional performance of the suspension but also incorporates the energy harvesting characteristics into the optimization objective. In the multi-objective optimization, a Pareto front is obtained, which shows that the ride comfort conflicts with the road holding and the energy harvesting power, while road holding and energy harvesting power did not conflict. The Pareto front shows that the optimized HIIRS is superior to the traditional suspension in ride comfort and road holding, and also harvests considerable energy.

Effect of Suspension Roll Angle Sensors on the Performance of H∞ Active Antiroll Bar Control System of Trucks

The rollover phenomenon is quite familiar with trucks and often has severe consequences worldwide. This article focuses on developing a new control structure for the active antiroll bar system using the robust control method. The main objective is to improve the vehicle’s roll stability by using additional suspension roll angle sensors. First, a truck model equipped with an active antiroll bar system is introduced. Then, the basic robust controller structure diagram is described in detail. Based on this basic robust controller, the authors develop a new robust controller considering the suspension roll angle sensors. Finally, the response of a truck using an active antiroll bar system with two robust (H∞) controllers and a passive antiroll bar system is compared and evaluated in the time domain and in the frequency domain. The results showed that the use of two sensors of the suspension roll angle sensors increased the efficiency by about 20% compared to the basic robust controller. This has proven the effectiveness of a new approach in improving the roll stability of trucks.

Sub-zero Quasi-static and Fatigue Behavior of SAE 1040 Automotive Anti-roll Bars in Flexure

Sub-zero Quasi-static and Fatigue Behavior of SAE 1040 Automotive Anti-roll Bars in Flexure

Influences of nonlinear suspension on the bus's roll stability by a lateral dynamic 4-DOF model

The influences of nonlinear suspension system with air spring and nonlinear asymmetrical (NA) absorber in comparison with a linear suspension is analyzed based on a lateral dynamic four degrees of freedom (4-DOF) model. The lateral dynamic model considers the effects of anti-roll bars, the roll center position, and the transient excitation of the road on the roll stability performance. The characteristics of the suspension system, the position of the roll center, the road excitation load all play very important roles in determining the roll stability of the vehicle. The maximum dynamic roll angle with nonlinear suspension is always smaller than that with linear suspension. The maximum dynamic rollover stability index is strongly dependent on the velocity and about 27% on average lower than that of linear suspension in the whole velocity domain, subjected under road excitation. However, the maximum of absolute acceleration is always larger with the nonlinear suspension system.

Development of a Fuzzy Algorithm With Multiple Inputs for the Active Stabilizer Bar to Improve Vehicle Stability When Steering

In this article, the author discusses the issue of vehicle roll instability when steering at high speeds. Installing an active stabilizer bar in a car is recommended to prevent it from rolling over and make it more stable when it does. A complex dynamic model is set up to evaluate and analyze vehicle oscillations. Besides, a fuzzy algorithm with three independent inputs is used to control the operation of the active stabilizer bar. This algorithm uses three separate inputs derived from the vehicle’s oscillating signals. In addition, the membership function and fuzzy rule are designed to ensure that the quality and efficiency of the system are well-maintained and stable. This is an entirely new method, which is rarely used for complex models of cars. Numerical simulation is carried out in a Simulink environment with many specific cases and situations. According to research findings, the roll angle of the vehicle body increases as the speed increases. This causes a greater change in wheel dynamics force and increases the risk of rollover. If the car is equipped with an active stabilizer bar controlled by the fuzzy algorithm with three inputs, these problems are significantly reduced compared to all other situations. So, when this new algorithm is added to the active stabilizer bar, the car’s stability and safety can improve even.

Pay load Stabilization for Offshore Cranes: A Unified Controller Based on Flatness

Crane-based handling operations represent a vital part of today's maritime sector. To guarantee both safe and efficient payload handling with ship cranes, payload oscillations induced by the sea swell have to be damped. Approaches for payload stabilization usually consider either vertical position control (Active Heave Compensation, AHC) or sway reduction (Anti Sway Control, ASC). In this paper, a unified control scheme for spatial payload stabilization is proposed, utilizing the differential flatness of the crane system. The presented framework inverts the nonlinear payload dynamics by means of the flat mapping, thus facilitating controller design. Furthermore, the approach provides a systematic way to include the sea disturbance in the controller. Redundancy of the considered knuckle boom crane is exploited to track secondary control objectives. A related cost function weighting the crane's manipulability is derived and used in an optimization-based target selector. The controller design is evaluated in simulation for varying sea disturbances. The results suggest good AHC and ASC capabilities, where the payload's position error is reduced up to 60% for light to medium sea states.

Characteristic Flow Behavior and Processing Map of a Novel Lean Si Spring Steel for Automotive Stabilizer Bars

The spring steel for automotive stabilizer bars has a great responsibility in that its quality directly affects the stability, safety, and comfort of vehicle operation. The isothermal thermal compression behavior of a novel lean Si spring steel that was used to manufacture an anti-roll bar was investigated with a DIL805A/D quenching thermal dilatometer in this research. A hyperbolic sine type of constitutive model was established, and hot processing maps were produced to evaluate the experimental steel’s hot workability properties. The experimental results suggest that dynamic recrystallization (DRX) preferentially occurs at a low strain rate and high thermal processing temperature, while the processing maps of the experimental steel are susceptible to strain. The instability regions increase as the strain increases. The processing maps’ stable and instable domains should be decided upon comprehensive analysis of the instability criterion, power dissipation efficiency, and strain rate sensitivity index. The optimum parameters of hot processing for the experimental steel at various strains are that the deformation temperature of 1000–1150 °C and the strain rate of 0.1, approximately.

Optimized Genetic Algorithms Reduced Order Model Based RST Roll Control of Antiroll Bar Dedicated to Semi-active Suspension

Working with high-order transfer functions needs a lot of work and leads to major difficulties in analysis, simulation, and control design. Model reduction studies the large-scale system properties and helps to reduce these difficulties. In this paper, the genetic algorithms (GA) optimization method is used to calculate the second reduced order model (ROM) of the original high order model (HOM) of the actuator. Here, the studied hydraulic actuator is a single input, single output (SISO), and linear time invariant (LTI) system that can be modeled by an eight-order transfer function with uncontrollable modes. The genetic algorithms are successfully applied to reduce the original model order using MATLAB software. Thus, the proposed approach is applied to both the original and suggested reduced order models to check the effectiveness of the reduction method. Finally, a digital RST roll control based on the robust pole placement is applied for the two models, and simulations are carried out to show the effectiveness of the control strategy

A complex rollover dynamics model with active stabilizer bar controlled by the fuzzy algorithm

The active stabilizer bar is used to improve the vehicle's safety when steering at high speeds. In this paper, the spatial dynamics model and nonlinear double-track dynamics model are used to simulate vehicle oscillations. Besides, the nonlinear tire model is also used. This is a completely novel and complex model. Besides, the fuzzy control algorithm is used to control the active stabilizer bar. This algorithm uses two input signals, which are obtained from the simulation. The membership function and fuzzy rules are designed optimally based on the results of many previous simulations and calculations. The simulation process is performed by MATLAB-Simulink software with three specific cases. The results of the paper show that the roll angle of the vehicle body and the change in vertical force at the wheel are significantly reduced when the vehicle uses the active stabilizer bar controlled by the fuzzy algorithm. The rollover phenomenon has been significantly improved in all the investigated cases, corresponding to three specific speeds. The stability and responsiveness of the controller are very high. The fuzzy algorithm can be combined with some other algorithms to improve system efficiency.

Towards the realization of an innovative rail vehicle — active ride comfort control

The Shift2Rail project Pivot2 introduces an innovative metro vehicle with two single axle running gears with only one suspension step to reduce the vehicle’s weight. A U-shaped connection frame is designed in Carbon Fibre Reinforced Polymer to further reduce weight and incorporate the anti-roll bar. Due to the poor ride comfort of the vehicle with standard passive dampers, all six dampers are replaced by hydraulic actuators. Modal control is applied and optimized with genetic algorithms. Despite the good improvements obtained, the weighted vertical acceleration remains above the acceptance level. Two modifications of modal control are studied, i.e., modal control with additional sensor, and blended control. Based on the frequency response of the results, it is proposed a low-pass filtered blended controller to neglect frame accelerations high frequency content. This last improves vertical comfort at the expenses of a more complex control system in comparison to modal control.

ANTI-ROLL BAR DESIGN FOR A FORMULA SAE VEHICLE SUSPENSION

This work outlines the development and analysis of an anti-roll bar system vehicle carried out by James Cook University. A detailed design phase was completed, clearly showing all stages of the design approach from the initial proposed design to the final design. Several analysis strategies are used throughout the report including weld calculations and FEA modelling. These calculations led to design changes impacting the final recommended system. This report demonstrates compliance with all Formula SAE rules regarding anti-roll bar systems.