• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.105-105
• /
• 2000

In this paper, an integrated control of the semi-active suspension system using a reduced full-car model is investigated. By including the reduced full-car dynamics in the control law, the semi-act ive suspension system is able to control not only the vertical acceleration but also the roll and pitch mot ions of the car body, which is not Possible with a quarter-car model or a half-car model. The damping forces for the semi-active dampers are designed to track the damping forces of the skyhook controller designed from the reduced full car dynamics. Computer simulations and experimental results using a real car are also included.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.23 no.11 s.170
• /
• pp.1912-1921
• /
• 1999

The equipments mounted on guided-missile undertake heavy vibrational disturbance. Sometimes the equipments mounted on guided-missile go wrong so that the guided-missile flies over unintended place. For the vibration isolation of the equipments mounted on guided-missile, active vibration control was performed. In the case of active vibration technique, the stiffness matrix and the mass matrix are derived based on FEM (ANSYS5.0). Model reduction was carried out and, as a result, we got 7 DOF mass and stiffness matrix. For the sake of FEM model identification, modal experiment was carried out. With the help of Sensitivity Analysis, the natural frequencies of FEM were tuned to those of Experiment. In this work, the Sky Hook and the LQG control theory were adopted for v iteration control using stacked piezoactuator. Experiments were performed with changing excitation frequency from 10 Hz upto 200 Hz and we got frequency response function of guided-missile equipments. The magnitude of 3rd mode of guided-missile equipments is 8.6 % that of Uncontrolled in Skyhook controller and is 3.4 % that of uncontrolled in LQG controller.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.26 no.2
• /
• pp.210-216
• /
• 2016

In this work, performance analysis to improve ride comfort of an ER (electrorheological) fluid damper for a mid-sized passenger vehicle in terms of tire pressure is presented. An ER damper by considering specification for a mid-sized commercial passenger vehicle is proposed and mechanically designed. After manufacturing and assembling the proposed ER damper with design parameters, their performance such as field-dependent damping forces are experimentally measured. A quarter-vehicle ER ECS (Electronic Control Suspension) system consisting of the ER damper, sprung mass, spring, sky-hook controller and tire is constructed to analysis the ride comfort performances. Vertical tire stiffness with different tire pressure is experimentally measured and investigated. In addition, ride comfort analysis such as vertical acceleration root mean square (RMS) of sprung mass is investigated under bump road using quarter-vehicle test equipment.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.27 no.1
• /
• pp.65-71
• /
• 2017

This work presents a comparative work on the ride comfort of a quarter car suspension system between two different magneto-rheological (MR) dampers; one is conventional type without bypass hole and the other is featured by several bypass holes in the piston. As a first step, two different MR dampers are designed on the basis of the governing equation and manufactured with same geometric dimensions except the bypass holes. After investigating the field-dependent damping properties, two dampers are installed to the quarter car suspension system. The suspension model is then derived and a sky-hook controller is implemented to identify vibration control performance under random road. It is shown that the suspension system with MR damper featured by the bypass holes can provide much better ride quality than the case without the bypass holes. This is validated via experimental implementation.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.1
• /
• pp.25-30
• /
• 2013

In military vehicles moving over poor roads, severe vibration of the chassis can damage internal components. Currently, many studies have focused on active and semi-active suspensions to reduce the vibration of the chassis. In this study, a vibration reduction technique is suggested by applying a unique rotating suspension structure. SH-ADD, a type of modified Skyhook, was selected as a controller for vibration reduction. A random ISO class E road was selected as the driving road. The simulation was performed using ADAMS Control and Matlab Simulink. The control result was compared with the RMS acceleration with a focus on the cumulative fatigue of the internal equipment.

• The Korean Journal of Rheology
• /
• v.11 no.2
• /
• pp.97-104
• /
• 1999

This paper presents vibration control of a drive feeding system consisting of a new type of CD-ROM(compact discread only memory) mount using electro-rheologocal(ER) fluid. Chemically treated starch particles and silicon oil are used for ER fluid. and its field-dependent yield stresses are experimentally distilled under both the shear and the flow modes. On the basis of the yield stress, an appropriate size of ER CD-ROM mount adapted to conventional feeding system is designed and manufactured. Vibration isolation performance of the proposed mount is evaluated in the frequency domain and compared with that of conventional rubber mount. The ER CD-ROM mount is then installed to the drive feeding system and the system equation of motion is derived. Following the formulating the sky-hook controller, computer simulation is undertaken in order to evaluate vibration suppression of the feeding system subjected to various disturbances(excitations).

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.4
• /
• pp.344-349
• /
• 2009

To improve performance of the main landing gear for helicopters, a semi-active control landing gear is introduced in this paper. An MR damper based on commercial finite element electromagnetic field analysis of an electromagnet has been adapted the shock absorber. Force control algorithm (which maintains constantly the sum of air spring force and damping force as internal forces) which keep the sum of air spring force and damping force constant during landing, has been used for the controller, applied to control the semi-active landing gear. A series of drop simulations using ADAMS has been done with the passive, sky-hook control type, and force control type landing gears. The result of each simulation has been compared to evaluate the landing performance of the proposed force control type landing gear.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.13 no.6
• /
• pp.967-975
• /
• 2010

There have been a lot of efforts on the improvement for the ride comfort and handling stability of the combat vehicles. Especially most of vehicles for military purpose have bad inertial condition and severe operating condition such as the rough road driving, and need a high mobility in the emergency status. It is necessary to apply the controlled suspension system in order to improve the vehicle mobile stability and ride comfort ability of crews. A feasibility study is performed on the application of the semi-active suspension system with a magneto-rheological controlled shock absorber for a $6{\times}6$ combat vehicle. First, the dynamic simulation model of the vehicle including the control model for the semi-active suspension system was executed. Based on this model, a hardware-in-the-loop simulation(HILS) system which has a semi-active suspension controller hardware was constructed. After full vehicle simulations were performed in virtual proving courses with this system, the semi-active suspension system was proven to give better ride comfort and handling stability in comparison with the conventional passive suspension system.