Time-delay based output feedback control of fourth-order oscillatory systems

We consider stabilization of the fourth-order oscillatory systems with non-collocated output sensing. Worth recalling is that are relatively common in mechatronics as soon there two-mass or more generally two-inertia dynamics significant elasticities between. A novel yet simple control method introduced based on time-delayed feedback. The delayed feedback requires only oscillation frequency to be known and allows for a robust design leads cancelation resonance peak. use stability margins justify transfer characteristics robustness time-delay domain. main advantage proposed over other possible lead-based loop-shaping strategies neither time derivatives noisy nor implementation functions numerator degree greater than zero required deploy controller. This comes favor practical applications. An otherwise inherently instable proportional-integral (PI) shown stabilized by method. developed associated analysis also confirmed experimental results low damped oscillator system uncertainties.