الفهرس | Only 14 pages are availabe for public view |
Abstract The main aim of this thesis is a mathematical study for mechanical vibrations of quarter car suspension system described by a nonlinear ordinary differential equation. It is being suggested some forms of active conventional control techniques with times delay to suppress its vibrations. They are proportional derivative (PD), positive position feedback (PPF), nonlinear saturation controllers (NSC), PD with PPF and PD with NSC. The comparison between the controllers output are investigated to get the best output of the controller by suppressing the vibration from the system. The car is excited by the disturbances on the road surface. The active controlled suspension system is investigated to comfort a ride improvement and provide good leveling of stability at simultaneous resonance. The main idea is attached the magneto-rheological or electrical-rheological damper in parallel with the hydraulic damper (passive element). The passive components are the backup for the failure of active controller .The controller is developed for suppressing the vibration of the closed loop control system and implementation by electronic system designed in the car. Then applying the multiple scales perturbation method to solve these nonlinear differential equations. The corresponding frequency-response equations are extracted and plotted at the different system parameters. The obtained graphs are confirmed numerically applying Rung-Kutta algorithm of fourth order. The concluded results are summarized and a comparison of the obtained results and the previously published results is held. Finally, a list of references are cited |