Simulation and Experimental of PSMEID with Preview for Controlling Shock Vibration on UAV's Landing Gear

Several studies have been conducted on developing semi-active shock absorbers operating based on the principle of momentum exchange, more commonly known as Pre-Straining Spring Momentum Exchange Impact Damper (PSMEID). The initial concept of developing PSMEID was introduced as a customizable passive shock absorber system that can be transformed into an active damper by adding a simple mechatronic system to activate the vibration-damping process. This research initially simulated and conducted experimental studies on applying PSMEID to dampen shock vibrations on the landing gear of uncrewed aerial vehicles (UAVs) with the addition of active time prediction (preview). This study proves that PSMEID equipped with an active time prediction system reduces the amplitude of shock vibration acceleration during the landing process. Placing PSMEID on the landing gear side (suspended mass) effectively reduces the maximum vibration acceleration values. Through simulations, the variation of the fall height determines when it is appropriate to activate the PSMEID to reduce the amplitude of the vibration excursion. Activating the PSMEID just before the impact of the landing gear on the runway surface is dominant to isolate the vibration in the main mass. Meanwhile, experiments using a drop-test mechanism with varying drop heights show that PSMEID can dampen maximum acceleration even when activated a few moments before impact. The phenomena observed in the experimental results are consistent with simulation outcomes for specific prominent mass cases. However, this research emphasizes that PSMEID should be equipped with a sensor system with impact time prediction to achieve more optimal results, as demonstrated in this research experiment.