Double Wishbone Suspension Research Articles

Dynamic Finite Element Analysis of Flexible Double Wishbone Suspension Systems with Different Damping Mechanisms

Suspension systems in running vehicles keep the occupants comfortable and isolated from road noise, disturbances, and vibrations and consequently prevent the vehicle from damage and wearing. To attain comfortable and vibration isolation conditions, both material flexibility and damping should be considered in the considered suspension model. This paper presents an incremental finite element model to study and analyze the dynamic behavior of double wishbone suspension systems considering both material flexibility and damping effects. The flexibility of the suspension links are modeled with plane frame element based on Timoshenko beam hypothesis (TBH). On the other hand, the flexibility of joints connecting the suspension links together and with the vehicle chassis is modeled with the revolute joint element. To incorporate the damping effect, viscoelastic, viscous and proportional damping are considered. An incremental viscoelastic constitutive relations, suitable for finite element implementation, are developed. The developed finite element equations of motion are solved using the Newmark technique. The developed procedure is verified by comparing the obtained results with that obtained by the developed analytical solution and an excellent agreement is found. The applicability and effectiveness of the developed procedure are demonstrated by conducting parametric studies to show the effects of the road irregularities profiles, the vehicle speed, and the material damping on the transverse deflection and the resultant stresses of suspension system. Results obtained are supportive in the mechanical design, manufacturing processes of such type of structural systems.

Design and analysis of double wishbone suspension system

Suspension system serves purpose of providing stability to vehicle which results improving comfortability of riding. It provides traction control and steering stability. This paper proposes a method for designing double wishbone suspension system for electric solar vehicle with damper to lower wishbone. Recent trends in suspension system have focused on improving innovations in ride quality and handling of vehicles. It maintains a viable spectrum of economic growth by reducing costs and increasing efficiency simultaneously. Theoretical analysis is conducted using Lotus and Solid works to design double wishbone suspension system. The analysis is done for tadpole geometry car with double wishbone in front and swing arm in the rear wheels. Results in the paper are going to improve vehicle handling characteristics by controlling camber, toe angles and A-arm’s length. This is accomplished by changing the length of A-arm and the ground clearance and attach angle with the chassis by hit and trial method and improving possible traction and maneuverability. Results of the paper are presented in form of graph as a result of simulation conducted.

Design and Optimization of Suspension and Steering System of Efficycle – Human Powered Hybrid Tricycle

Suspension is a system of tires, springs, shock absorbers, and linkages that connects a vehicle’s chassis to its wheels and allows relative motion between the two. Steering is a mechanism that provides a direction to the vehicle, it basically consists of gears, shaft, joints, steering column, steering wheel, and furthermore. The main objective of this paper is to design a system of suspension and steering for a three-wheeled human-electric hybrid trike. A system of directly actuated double wishbone suspension system is chosen for the front and a pushrod actuated 2-link trailing arm suspension system for the rear. The steering system used is a type of Single tie rod and drag link system. A knuckle-to-knuckle drag link provides continuity to the wheels and a tie rod to the bell crank provides steering rotation. This paper also talks about the single nut hub-shaft system which is being used in the front suspension system. Based on the research using various input parameters, the inboard and outboard suspension hardpoints are decided to maximize the tire contact patch at every vehicular motion (mainly during body roll). Forces and stresses are calculated with the help of Free Body Diagrams (FBD) and Multi-Body Dynamics (MBD) software LOTUS Shark. The paper discusses the calculations regarding the roll and ride rates and for the custom springs of specific stiffness used in front and rear shock absorbers and the variation of roll steer and bump steer on changing various parameters of the steering system. Key points also include the procedure of selections of various types of bearings, rod ends, and bolts. This paper also talks about laser-cut jigsaw uprights that are used in the front wheel assembly. The finite element method was used to analyze the designs using DS Solidworks and Ansys Workbench. Static structural and explicit dynamics analysis was performed on the wheel assembly components both individually and assembled

Interaction between asymmetrical damping and geometrical nonlinearity in vehicle suspension systems improves comfort

This work explores the role of asymmetrical damping and geometrical nonlinearities in the suspension system of a simplified vehicle model in order to improve comfort. Improving comfort for passengers is a constant challenge for the automotive industry. Although technologies have been introduced for this purpose, many vehicles still use suspension systems which are less effective in vibration isolation due to cost restrictions. To improve comfort at relatively low cost, the use of asymmetrical suspension dampers has been explored. It has been shown that different asymmetry ratios can be advantageous to improve comfort at different frequency ranges. Models which include the suspension geometry can help to better understand the vehicle dynamical response, as it also depends on the geometrical arrangement of its components. As a contribution to the current literature, this paper proposes a study on asymmetrical damping considering a Double Wishbone suspension geometry. A nonlinear single-degree-of-freedom system subject to harmonic base excitation is used. The combination of asymmetry and geometry nonlinearities is investigated for varying asymmetry ratio, geometrical parameters and vehicle velocity. The numerical and experimental results show that the geometrical nonlinearity induces changes in the spring and damping forces because of different inclinations of the spring–damper assembly during expansion and compression, resulting in changes in acceleration amplitude and resonance frequency. This effect is superimposed on the effect of asymmetrical damping coefficient alone, ultimately influencing the acceleration of the suspended mass. Therefore, these two effects must be considered carefully when designing a suspension system with comfort criteria.

Straight Path Handling Anomalies of Passenger Cars Induced by Suspension Component and Assembly Tolerances

The effects on handling due to suspension component and assembly tolerances are analysed focusing on three anomalies affecting passenger cars travelling on straight paths, namely ‘pull to side’, ‘steering wheel misalignment’ and ‘drift leeward’. These anomalies do not constitute safety problems but represent a cost factor in the automotive industry since they occur in small but not negligible percentage of the overall car production. The present contribution is therefore focused on understanding which are their causes, and on reducing their extent, in the specific case of vehicles with front Double wishbone suspension and rear Five arms suspension. To this purpose, the vehicle assembly process is analysed in terms of errors and tolerances for identify the most influential parameters on handling irregularities. Sensitivity analysis by multibody virtual modelling, and subsequent correlation with experimental data from pre-setting and wheel aligner benches, have provide sufficient information for setting tolerance thresholds, able to keep the handling anomalies under study within acceptable bounds. As a result, ‘pull to side’ and ‘steering wheel misalignment’ has been found to be mainly related to the set up phase of wheel angles (front camber angles influencing pull to side, front and rear toe angles influencing steering wheel misalignment), while the main cause of ‘drift leeward’ has been identified with (rear) ride steer. Application of the procedure to a production line led to a consistent reduction (from 3% down to about 1% of the overall production) of anomalous vehicles.

Passenger car steering pull and drift reduction considering suspension tolerances

Pull to side, Steering wheel misalignment and Drift leeward are handling anomalies affecting passenger cars travelling on straight paths. They represent a cost factor in the automotive industry, occurring in small but not negligible percentage of the overall car production. The present contribution is aimed at understanding which are their causes in terms of suspension tolerances, and at reducing their extent, in the specific case of vehicles with front Double wishbone suspension and rear Five arms suspension. The most influential parameters on handling irregularities have been identified through a design of experiment analysis. Then, after performing a sensitivity analysis by multibody virtual modelling, a correlation with experimental data from presetting and wheel aligner benches has provided sufficient information for setting tolerance thresholds, able to keep the handling anomalies under study within acceptable bounds. Pull to side and Steering wheel misalignment have been found to be mainly related to the set up phase of wheel angles (front camber angles influencing Pull to side, front and rear toe angles influencing Steering wheel misalignment), while the main cause of Drift leeward has been identified with (rear) ride steer.

Enhancement of Vehicle Wheel Vibration Level by using active Camber angle based on a Double Wishbone System

Active camber angle position systems for vehicle wheel alignments can better regulate the wheel camber angle position in different operating conditions of vehicles. The aim of this work is to illustrate the application of active camber angle position theory. A prototype of one wheel equipped by the double wishbone suspension system and the variable camber angle control with suspension system concept is proposed. Active camber system uses a linear actuator with Arduino microcontroller. A comparative study was done on wheel vibration characteristics of the conventional camber system (passive system) and active system. The experimental results and analysis show that the vibration signature is influenced by the camber angle position. It is found that the vibration signal increases when the vehicle wheel speed and normal load are increased. Moreover, the results indicate that the root mean square (RMS) of vehicle wheel vibration is improved by 17.78%, 38.6% and 49.63% at wheel speed of 250 rpm, 500 rpm and 750 rpm respectively by using the proposed active camber angle. The vehicle wheel vibration behaviour with active camber angles is likely to be optimum under the different wheel operating conditions.

Double Wishbone Suspension System; A Research

Advancements in science and technology, effective designs and newly advanced ways of manufacturing for the need to fulfill the customer expectations and to provide them better goods has let to these developments. With the invent and help of numerous mechatronic systems there is technological advancements in various automobile sectors and thus gave better performance output A suspension system has responsibility of safety of both the vehicle and occupants by providing stability and comfort ride during its maneuvers. Without the help of any suspension system, it would have made extremely hard for a driver to control a vehicle since all the shocks and vibrations would have been directly transmitted to steering without any damping. The main aim of this study to discuss about the designing and analysis of double wishbone suspension system for automobile.

Analysis of the Dynamic Behavior of the Double Wishbone Suspension System

Suspension systems are essential in vehicles to provide both passenger comfort and vibration isolation from road bumps. It is necessary to develop a comprehensive numerical model to study and analyze the dynamic behavior of these systems. This study aims to introduce a comprehensive finite element model to investigate the dynamic behavior of double wishbone vehicle suspension system considering links flexibility. Plane frame element based on Timoshenko beam theory (TBT) is adopted to model the suspension links. Flexibility of the joints connecting the suspension links are modeled using the revolute joint element. Viscoelastic, viscous and proportional damping models are considered to simulate the damping effect. Newmark technique, as unconditionally stable technique is adopted to solve the finite element dynamic equation of motion. The developed procedure is verified by comparing the obtained results with the available analytical and numerical results and an excellent agreement is found. To demonstrate the effectiveness of the developed model, parametric studies are conducted to show the effects of the road bump profiles, the vehicle speed, and the material damping on the dynamic behavior of suspension system. The obtained results are supportive in the design and manufacturing processes of such suspension systems.

REVIEW ON THE DESIGN AND ANALYSIS OF VEHICLE SUSPENSION SYSTEM

In automobiles, a double wishbone suspension is an independent suspension design using two wishbone-shaped arms to support the wheel and the maximum load is transferred from upper wishbone arm to the lower arm which may cause failure and bending of lower wishbone arm. The developed lower control arm consists of three holes at one end, which are fixed to the wheel hub and other end is connected with chassis which is placed in between the steering link. In this study, topology optimization approach is presented to create a new design of a lower control arm.

Quarter-Car Experimental Study for Series Active Variable Geometry Suspension

In this paper, the recently introduced series active variable geometry suspension (SAVGS) for road vehicles is experimentally studied. A realistic quarter-car test rig equipped with double-wishbone suspension is designed and built to mimic an actual grand tourer real axle, with a single-link variant of the SAVGS and a road excitation mechanism implemented. A linear equivalent modeling method is adopted to synthesize an H-infinity control scheme for the SAVGS, with the geometric nonlinearity compensated. Simulations with a theoretical nonlinear quarter-car indicate the SAVGS potential to enhance suspension performance, in terms of ride comfort and road holding. Practical features in the test rig are further considered and included in the nonlinear model to compensate the difference between the theoretical and testing behaviors. Experiments with a sinusoidal road, a smoothed bump and hole, and a random road are performed to evaluate the SAVGS practical feasibility and performance improvement, the accuracy of the model, and the robustness of the control schemes. Compared with the conventional passive suspension, ride comfort improvements of up to 41% without any deterioration of the suspension deflection are demonstrated, while the SAVGS actuator power is kept very low, at levels below 500 W.

Finite Element Analysis of Double Wishbone Vehicle Suspension System

Suspension systems play an important role in vehicles. These systems provide passenger comfort and vibration isolation from road bumps. Thus an efficient finite element model is required to study and analyze the dynamic response of these suspension systems. This paper presents a finite element model to analyze the dynamic response of double wishbone vehicle suspension system taking into consideration both links and joints flexibilities. Links are modeled using plane frame element based on Timoshenko beam theory (TBT) kinematic relations. On the other hand, the revolute joint element, developed in ANSYS, is adopted to model joints flexibility.Both internal viscoelastic and external viscous as well as the modal proportional damping models are adopted to simulate the damping effect. The resulting dynamic finite element equations of motion are solved using Newmark numerical technique. The proposed numerical methodology is checked by comparing the obtained results with the developed analytical solution and good agreement is noticed. The applicability of the proposed procedure is demonstrated by operating parametric studies to illustrate the effects of the road irregularity configurations, the vehicle travelling velocity, as well as the material damping on the dynamic response characteristics of the double wishbone suspension system. The obtained results are helpful for the mechanical design of these structural systems.

Double Wishbone Suspension System of BAJA ATV

Suspension is the main system of the vehicle. It’s function is to isolate the driver from road shocks. Secondary function includes load transfer, lateral stability and providing adequate wheel travel ensuring ergonomics and driver comforts. By using the CREO software wishbone arm is prepared and analysis is done. The forces are applied on the basis of vehicle weight and the forces acting on the suspension system while vehicle is moving. The selection of material is done on the basis of result of analysis. To get the best result the geometry of Double Wishbone Suspension System is done precisely.

Design and Analysis of Wishbones in Double Wishbone Suspension System: Technical Note

This paper details the design and analysis of the wishbones in double wishbone suspension system. Initially Pugh’s matrix approach is used to score the conventional materials and light weight metal matrix composites for the wishbone design. Based on the scores, an Alumina matrix composite has been found as the preferred material. Then, the designed wishbones were analysed using ANSYS finite element analysis software using AISI 1040 and metal matrix composite materials. Based on the FEA results, it has been concluded that the metal matrix composite yielded a better durability and strength than conventional metal.

Parallel Active Link Suspension: A Quarter-Car Experimental Study

In this paper, a novel electromechanical active suspension for cars, the parallel active link suspension (PALS) is proposed and then experimentally studied. PALS involves the introduction of a rotary-actuator-driven rocker–pushrod mechanism in parallel with the conventional passive suspension assembly, to exert an additional controlled force between the chassis and the wheel. The PALS geometric arrangement is designed and optimized to maximize the rocker torque propagation onto the tire load increment. A quarter-car test rig with double wishbone suspension is utilized for the PALS physical implementation. Based on a linear equivalent model of the PALS quarter car, a conservative and an aggressive robust $H_{\infty }$ control schemes are synthesized separately to improve the ride comfort and the road holding, with different levels of control effort allowed in each of the control schemes. Simulations with a theoretical nonlinear model of the PALS quarter car are performed to evaluate the potential in suspension performance enhancement and power demand in the rocker actuator. Experiments with a harmonic road, a smoothed bump and hole, and swept frequency are conducted with the quarter-car test rig to validate the practical feasibility of the novel PALS, the ride comfort enhancement, and the accuracy of the theoretical model and of a further nonlinear model in which practical features existing in the test rig are identified and included.

Mathematical model and performance calculation of a double-wishbone independent suspension

The paper presents a mathematical model based on which performance calculations of a double-wishbone independent suspension are performed. First, the spatial motion of a rigid body was described by coordinate transformation, which provides the theoretical basis for the hard point coordinate calculation of double-wishbone suspension mechanism. After that, a mathematical model of the wheel guide mechanism has been built, and the kinematic performance and hard point reaction load were calculated. The results obtained are useful in the design of new suspension systems.

Efficient modelling and optimization for double wishbone suspensions based on a non-adaptive sampling sparse response surface

ABSTRACTThe response surface method is always used in optimization problems such as the optimization of vehicle suspensions because of its efficiency. A sparse response surface (SRS) is proposed to represent a double wishbone suspension model constructed from a few non-adaptive sampling points. One set of sampling points can be applied to all response surfaces. In this problem, four variations of the front wheel positioning parameters are considered as the optimization objectives, and four parameters are considered as the design variables. Four SRS models with four variables are constructed from 60 sampling points. The interior point method is employed to optimize the problem. The optimization results show that the objective of the camber angle reduces from to , the objective of the caster angle increases from to , the objective of the kingpin inclination angle reduced from to , and the objective of the toe angle increases from to .

Adaptive suspension strategy for a double wishbone suspension through camber and toe optimization

A suspension system is responsible for the safety of vehicle during its manoeuvre. It serves the dual purpose of providing stability to the vehicle while providing a comfortable ride quality to the occupants. Recent trends in suspension system have focused on improving comfort and handling of vehicles while keeping the cost, space and feasibility of manufacturing in the constraint. This paper proposes a method for improving handling characteristics of a vehicle by controlling camber and toe angle using variable length arms in an adaptive manner. In order to study the effect of dynamic characteristics of the suspension system, a simulation study has been done in this work. A quarter car physical model with double wishbone suspension geometry is modelled in SolidWorks. It is then imported and simulated using SimMechanics platform in MATLAB. The output characteristics of the passive system (without variable length arms) were validated on MSC ADAMS software. The adaptive system intends to improve vehicle handling characteristics by controlling the camber and toe angles. This is accomplished by two telescopic arms with an actuator which changes the camber and toe angle of the wheel dynamically to deliver best possible traction and manoeuvrability. Two PID controllers are employed to trigger the actuators based on the camber and toe angle from the sensors for reducing the error existing between the actual and desired value. The arms are driven by actuators in a closed loop feedback manner with help of a separate control system. Comparison between active and passive systems is carried out by analysing graphs of various parameters obtained from MATLAB simulation. From the results, it is observed that there is a reduction of 58% in the camber and 96% in toe gain. Hence, the system provides the scope of considerable adaptive strategy in controlling dynamic characteristics of the suspension system.

Active camber and toe control strategy for the double wishbone suspension system

The present research work proposes a method for improving handling characteristics of the vehicle by controlling camber and toe angle using double wishbone suspension arms in an adaptive manner. This is accomplished by two telescopic arms with actuators which changes camber and toe angle of the wheel dynamically to deliver best possible traction and manoeuvrability. Active suspension controllers are employed to trigger the actuators based on the camber and toe angle from sensors for reducing the existing error. Hence the arms are driven by the actuators in a closed loop feedback manner with help of a separate PID controller. A quarter car physical models with double wishbone suspension is modelled in SolidWorks and simulated using MATLAB for analysis. The simulation result shows an improvement of 58% in camber and 96% improvement of toe characteristics. A prototype of the proposed system is developed and subjected to the same test as the simulation system. The prototype achieved an improvement of 46.34% in camber and a 93.35% in the toe variation of the active system over the passive system. Further, the prototype was able to achieve 89% of camber reduction and 45% of toe reduction with respect to the simulation.

Multi-objective optimization of double wishbone suspension of a kinestatic vehicle model for handling and stability improvement

One of the important problems in the vehicle design is vehicle handling and stability. Effective parameters which should be considered in the vehicle handling and stability are roll angle, camber angle and scrub radius. In this paper, a planar vehicle model is considered that two right and left suspensions are double wishbone suspension system. For a better analysis of the suspension geometry, a kinestatic model of vehicle is considered which instantaneous kinematic and statics relations are analyzed simultaneously. In this model, suspension geometry is considered completely. In order to optimum design of double wishbones suspension system, a multi-objective genetic algorithm is applied. Three important parameters of suspension including roll angle, camber angle and scrub radius are taken into account as objective functions. Coordinates of suspension hard points are design variables of optimization which optimum values of them, corresponding to each optimum point, are obtained in the optimization process. Pareto solutions for three objective functions are derived. There are important optimum points in these Pareto solutions which each point represents an optimum status in the model. In other words, corresponding to any optimal point, a specific geometric position is determined for the suspension hard points. Each of the obtained points in the Pareto optimization can be selected for a special design purpose by designer to create an optimum condition in the vehicle handling and stability.