The spring rate (or suspension rate) is a component in setting the vehicle's ride height or its location in the suspension stroke. Vehicles which carry heavy loads will often have heavier springs to compensate for the additional weight that would otherwise collapse a vehicle to the bottom of its travel (stroke). Heavier springs are also used in performance applications where the loading conditions experienced are more extreme . Magneto rheological (MR) fluid, which is capable of controlling the stopping process of moving objects, e.g. on transportation lines. The proposed solution makes it possible to adjust the braking force (by electronic controller) to the kinetic energy of the moving object. The paper presents an overview of passive shock absorbers. Next, the design concept of a semi- active shock absorber with the MR fluid is proposed.
Automotive industry is fastest growing industry in today’s era. The quality of the suspensionsystem decides the future of the vehicle. One can say that suspensionsystem works as WBC works in a blood. Analysing suspensionsystem has become need of the automotive industry now days. Most of the research studies show that analysis of vehiclesuspension systems is necessary to improve comfort of the passenger. To simplify the vibration analysis of the suspensionsystem quarter car model is used. Quarter car model consist of the 1/4 th of the total mass of the vehicle. According to the work done by O. Gundog˘ du, the health of the driver is as important as the stability of the car, the desired objective is proposed as the minimization of a multi objective function formed by the combination of not only suspension deflection and tire deflection but also the head acceleration and crest factor (CF), which is not practiced as usual by the designers. Tamboli J. A. and Joshi S. G. , have found that the power spectral density of actual road profile follows an approximately exponentially decreasing curve. In “Quarter Model Analysis of Wagan-R car’s Rear Suspension using ADAMS”, they have prepared the quarter car model for rear suspensionsystem in Pro-e. Then it is imported in the ADAMS for force and deflection analysis is done, saying that an excessive load will create dis- comfortness for sure as well as it affects on stability and ride handling. Most of the research studies includes the quarter car model for analysis. Li Xueying, Yu Zhuoping, and Xiong Lu, says that, The torque vibration derived from in- wheel-motor transmits to body frame through suspensionsystem without the absorption of mechanical transmission parts, which influenced the quality of the vehicle NVH. In the present work, two quarter car models are prepared, One in the SIMULINK and other is in MSc-ADAMS. at first the mathematical model for quarter car is prepared using state space representation. This paper also discuss the development of quarter car model in SIMULINK first and then in MSc-ADAMS.
Today’s world is full of modern technologies and automotive industry is one of the industry that is evolving to modern technology. Hybrid and electric car is under improvement for a better efficiency. This paper emphasizes the development and analysis of retrofit electromagnetic energy regenerative suspensionsystem test rig. The test rig will be used for the testing of the system in the laboratory. The system functions as the harvesting system that generates power for vehicle usage. Complete design of the test rig is clearly discussed in the paper including the drafting, analysis and fabrication. It is get that the designed test rig can be used for the testing which has been assembled with the main component of the real vehiclesuspensionsystem with the regenerative system. The test rig can be useful for validating the real vehicle test with the laboratory test.
ABSTRACT: Suspension is the most vital sub-system in an automobile. Its main functions are load transfer to the wheels and protection of the driver from road shocks. The purpose of this paper is to select suitable suspensionsystem for the front and the rear of an All-Terrain Vehicle (ATV) with rear electric drive and to thereafter design, analyze, simulate and test the suspension systems for optimum performance of the vehicle, driver safety and maximum driver comfort. The camber and caster angles, toe and the Ackermann variations were given due consideration. The stability of the vehicle was given importance and the system was designed to be durable enough to withstand shocks from the harsh terrain where ATVs are generally used. The springs were designed by calculations and the components were designed using CATIA. The components were analyzed using NASTRAN/PATRAN commercial FEA software andthe front and rear systems were simulated using Lotus software. The system was then fabricated and its performance was duly tested.
There have been several kinds of interconnected suspensions proposed in the past, and most claim to offer improved performance. However, the method evaluated in the current work is novel. It uses an all mechanical implementation for the sake of simplicity and cost, rather than a hydraulic system. In addition, the proposed system has no influence on bounce or pitch stiffness, but aims to increase roll stiffness without the corresponding increase in twist stiffness that accompanies traditional anti-roll bars. According to Zapletal[ ? ], roll stiffness is necessary to prevent excessive body motions during cornering, but twist motion of the suspension can only occur on uneven road surfaces, and so high twist stiffness only contributes to uneven tire loads, and is generally not desirable. The suspension displacement modes are illustrated in Figure 2.14.
Linear electromagnetic motor (L.E.M.) can be used at each wheel, in lieu of a conventional shock and spring setup. The L.E.M. has the ability to extend (as if into a pothole) and retract (as if over a bump) with much greater speed than a fluid damper (taking just milliseconds). These lightning-fast reflexes and precise movement allow the wheel's motion to be so finely controlled that the body of the car remains level, regardless of the goings-on at the wheel level. Inside the linear electromagnetic motor are magnets and coils of wire. When electrical power is applied to the coils, the motor retracts and extends, creating motion between the wheel and car body. One of the key advantages of an electromagnetic approach is speed. The linear electromagnetic motor responds quickly enough to counter the effects of bumps and potholes, maintaining a comfortable ride. Additionally, the motor has been designed for maximum strength in a small package, allowing it to put out enough force to prevent the car from rolling and pitching during aggressive driving manoeuvres. The L.E.M. can also counteract the body motion of a car while accelerating, braking and cornering, giving the driver a greater sense of control and passengers less of a need for Dramamine. To further the smooth ride goal, wheel dampers inside each wheel hub smooth out small road imperfections, isolating even those nuances from the passenger compartment. Torsion bars take care of supporting the vehicle, allowing the system to concentrate on optimizing handling and ride dynamics. A power amplifier supplies the juice to the L.E.M.s. The amplifier is a regenerative design that uses the compression force to send power back through the amplifier.
tire side slips angles in front-wheel steered, rear-wheel driven four wheeled vehicles. A three degree-of-freedom model with slip angle, yaw rate and roll angle as degrees of freedom was constructed to capture the coupling between steering and roll dynamics of such vehicles. An open-loop estimator was designed based on this model to estimate the side slips angles of tires using available real-time measurements which include steering angle, steering torque and suspension positions. The model incorporates all sources of compliance, stiffness and damping, all with non-linear characteristics. The vehicle model is created in ADAMS (automatic dynamicanalysis of mechanical systems) formulation. The model is used for the purpose of vehicle handling analysis. The estimator was validated by comparing its predictions with that of an ADAMS model. The paper presents a comparative analysis between different half-car models for the suspensionsystem of the rear axle of the motor vehicles, the difference between models consisting of how the equilibrium of the car body is assured.
analyze the suspensionsystem for a formula student vehicle. The suspensionsystem is one of the main systems to be considered while designing any formula student vehicle. The aim of the paper is also to lay a proper methodology for designing and analysis of a suspensionsystem which includes knuckle, wishbones and spring. ADAMS is used for the dynamic simulation of the system. Special emphasis is laid on achieving accurate results by using software based analysis. The results of the simulation in ADAMS are also shown for better understanding of the system. The 3D modeling of the system is done in CATIA V5R21. Analysis is carried out in ANSYS V16. Dynamic simulation is carried out in ADAMS.
Ride comfort is a key issue in design, development and manufacturing of modern automobiles and efforts of all designers are concentrated towards it. As confort is a main objective advanced suspension systems are emerging as a results of the efforts of modern designers. These newly developed and improved designs are capable of providing comfortable ride to the passengers by absorbing shocks and vibrations of the road. These systems provides good vehiclestability also. In last decades due to demand of automobile industry many researchers participated in the research on improvedsuspension systems .
The arms were decided to keep as long as possible for the stability of the vehicle and minimize the variations in geometry. The length of the upper arms was decided through geometry modeling, shorter upper arm meant negative camber in bump travel and optimum roll-camber coefficient. The design of suspension begins with considering some important factors. The requirement for a good suspensionsystem is to select good dampers, types of suspensionsystem considering which is best suited for the current chassis design and steering system.
A hybrid combination of adaptive control and fuzzy logic is an attractive and powerful approach for designing robust control systems with high degrees of nonlinearities and uncertainties. If human information is about nonlinear dynamic systems that is a direct adaptive fuzzy and if human information is about control of a system that is indirect adaptive fuzzy. There are many papers in the field of adaptive fuzzy controller. For example Wang in 1993  has designed a direct adaptive fuzzy and he has gotten adaptive rules with lyapanove theory. Also Wang at 1996  kind of general solution for designing of stable adaptive fuzzy controller with lyapanove theory presented and he used the controller in inverted pendulum of two degrees of freedoms. After that Tang  designed an adaptive fuzzy controller base of input and output of the nonlinear system model. Shahnazi and Akbarzade in 2008 have been introduced indirect adaptive fuzzy of the PI controller versus routine adaptive fuzzy controller that the speed convergence in near of equilibrium point . Also Lee et al. in 2012 an adaptive fuzzy presented for control of random system .
The objective of designing a single-passenger off-road race vehicle with high safety and low production costs seems to be accomplished. The design is first conceptualized based on personal experiences and intuition. Engineering principles and design processes are then used to verify and create a vehicle with optimal performance, safety, manufacturability, and ergonomics. The design process included using Solid Works, CATIA and ANSYS 14.0 software packages to model, simulate, and assist in the analysis of the completed vehicle. After initial testing it will be seen that our design should improve the design and durability of all the systems on the vehicle. The Roll-cage Design by analyzing the failures on static structural analysis on ANSYS & the suspensionsystem designed by considering all the input parameters on LOTUS SUSPENSIONSYSTEM can be further modified for decreasing the weight and cost. Transverse leaf spring can be used to reduce the distribution of sprung weight on the suspension assembly. Pneumatic suspensions can be added in the future for better performance.
Abstract -An electromagneticsuspensionsystem is designed with increased comfortness and reduced annoying sounds in automobiles. It also prevents the floor damages from automobiles due to vibration. Now a days the automobiles and machines use incompressible fluids in shock absorbers to absorb sudden shocks and vibrations that arise under motion. In our project, electromagnetic coil is used to absorb the shocks experienced by the vehicle. The shock absorber is fabricated for the equipment like automobiles and movers which are suitable for AC & DC supplies up to 12V to 220V. In our project, electro-magnetic coil is operated at 12V D.C battery supply.
One of the roots of vehicle vibrations and shakes is the road roughness. Shocks due to bumps on the road are transferred to the vehicle body through the wheels and not only make discomfort for passengers but also reduce the quality of driving. In this paper, a vehiclesuspensionsystem will be designed. Then its performance will be shown through analysis and simulation. The main idea is based on the combination of a nonlinear energy sink and a skyhook. The performance of the proposed suspensionsystem will be evaluated by comparing car body vertical accelerations and suspension deflections with a passive suspensionsystem. The sliding mode control as a robust nonlinear control method has been used to make the system robust to changes and uncertainties in car model. The Lyapunov based stabilityanalysis shows that the tracking error of proposed system will asymptotically approach zero.
The design is based on Instant axis concept. Instant axis was obtained by connecting ICRs in both side view and front view. Various constraints such as chassis, differential, mounting tabs etc. were considered. Iterations were done by changing the position of ICR and the link angles. One with minimum camber change, wheelbase change and track width change was finalized. Knuckle pivot points were assumed considering the packaging of the wheel assembly. Iterations were done using CREO 3.0.
Suspension Systems to reduce the vibrations occurring during vehicle use was done by Isa & Liza et al.(4), in which the possibility of complete elimination of vibrations using a Fully Active Suspensionsystem was considered – however, the main disadvantage with such a system is the running cost (since continuous monitoring, feedback and actuation of suspension elements is required), the weight, and the size of the system.
This paper presents the simulation and designanalysis of fully integrated receiver system for millimeter and microwave applications. A beauty thought of new design of CMOS LNA, filter and microstrip antenna are largely improves the system integration, reduced chip area and save the cost. In this paper, a three different architecture are proposed and analyzed through Agilent ADS tool. We have designed 90nm CMOS LNA at 40GHz to integrate with band pass filter and rectangular patch antenna at same frequency. As shown by simulation results: achieved minimal noise figure of 3.8dB and gain of 26dB from the LNA side. A Co-design of filter and rectangular micro-strip antenna at 40GHz is to relax the 50Ω impedance matching constraints and to provide S 11 of -13.09dB and VSWR is 1.5. A
A calculation of the suspension of bus B3 090 T was done. We calculated all parameters which are of significance for the comfort in the bus and for dynamic forces on the wheels. Finally, we deter mined the optimum values for parameters of su spension for optimum comfort and for minimum dynamic forces. We found that a good choice of the suspension parameters was made on the existing bus, since the compromise between comfort and dynamic forces was considered. There are certain possibilities of improving both the comfort and the dynamic forces. We carried out also the measure ments of autospectra during operation. One shall compare these measurements with the calculati ons, establish the quality of the bus model and then improve the model. We shall thus gain the neces sary experience for correct modelling of buses and for the selection of suspension elements.
Now, after finding out the Velocity and Acceleration value, we want to find out the Damping Factor or Damping Ratio. Damping Ratio is a Dimensionless Parameter measure describing how oscillations in a system decay after a disturbance. Many systems exhibit oscillatory behavior when they are disturbed from their position of Static Equilibrium. A mass suspended from a spring, for example, might if pulled and released, it will bounce up and down.