International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 11 | Nov 2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 703 Experimental Analysis of Passive/Active Suspension System Shivaji Gadadhe 1 , Amol More 2 , Nitin Bhone 3 1,2,3 Assistant Professor mechanical Engineering Department, AISSMS Institute of Information Technology Pune, MH, India ----------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - The suspension system classified as a passive, semi-active, and active suspension, according to its ability to add or extract energy. Active suspensions have recently attracted increased attention in automobile industry because they can significantly improve vehicle ride and handling performance. The control object of an active suspension system is to produce excellent ride comfort and good holding ability. Optimal control theory was used to investigate potential benefits of active suspensions. This study addresses the main characteristics of optimal active suspension based on two degree-of-freedom quarter car vehicle models. In this study MATLAB software is used for see the results of active and passive suspension system. Modeling of quarter car suspension system with the help of 2 DOF model of vibratory system such as mass, spring and damper arrangement done. Mathematical analysis done here by using Laplace transform because it is very simple to use in MATLAB and results taken. Simulation is also done here by using simulink library of matlab, sources, sinks and continuous library used for simulation. Also experimental set up done, for this used masses and shock absorbers in vertically arrangement. Here also design of active control strategy such as Proportional Integral Derivative controller. In addition, the study puts into perspective the optimal active suspension performance through comparison with corresponding passive counterparts. The simulation results indicate that the proposed active suspension system proves to be effective in the vibration isolation than passive suspension system. Key Words: Active and Passive Suspension System, DOF model, PID, Vibration 1. INTRODUCTION The main functions of an automotive suspension system are to provide vehicle support, stability and directional control during handling maneuvers and to provide effective isolation from road disturbance. These different tasks result in conflicting design requirements, directional control and stability requires a stiff suspension, whereas good ride comfort demands a soft suspension. In conventional passive suspension system, the designer is faced with problem of choosing the suspension stiffness and damping parameters, which inevitably involves a difficult compromise in view of the wide range of conditions over which a vehicle operates. This type of active suspension system has proven capable of achieving improvement over passive systems. The primary thrust of the commercial research and development in active suspension has been improved ride handling and stability in the on-road environment while minimizing system cost and mean time between failures. Much of this work was pioneered by lotus engineering, located in Norwich, England and has been continued by several major automotive manufactures, including U.S. based ford and GM. Though the performance results have been quite promising, cost, reliability and potential safety issues have limited the production commitments for active suspension to only Toyota and Nissan. With recent advances in microelectronics and actuators, there has been an upsurge in the concept of active suspension control. Active suspension offers the potential of being adapted to the quality of the road surface, vehicle speed and different safety and comfort requirements, with the choice being selected either by the driver or by an adaptive control algorithm embodied in a microcontroller. The issue of vehicle suspension damping is the conflict between vehicle safety and ride comfort. The safety of a vehicle is typically measured by the vertical motion of the vehicle tires (wheel hop) and by the rotational motions of the vehicle body, such as the roll and pitch of the vehicle during cornering and braking. These measures are also considered as road handling and stability characteristics by providing information on the vehicle tire contact to the road and the location of the vehicle’s center of gravity. The degree of ride comfort of a vehicle is obtained by evaluating the displacements and accelerations of the vehicle body. This provides a measure of the movement and forces transmitted to the vehicle passenger, which cause discomfort. Two common types of vehicle suspension dampers are passive and semi active dampers. With each of these dampers, the magnitude of damping is dependent on the relative velocity across the damper. The force versus velocity curves of each type of damper, however, is not identical. 2. ACTIVE SUSPENSION SYSTEM Traditionally automotive suspension designs have been a compromise between the three conflicting criteria of road holding, load carrying and passenger comfort. The suspension system must support the vehicle, provide directional control during handling manoeuvre and provide effective isolation of passengers/payload from road disturbances. Good ride comfort requires a soft suspension, whereas insensitivity to applied loads requires stiff suspension. Good handling requires a suspension setting somewhere between the two. Due to these conflicting demands, suspension design has had to be something of a compromise, largely determined by the type of use for which the vehicle was designed. Active suspensions are considered to be a way of increasing the freedom one has to specify