Nonlinear dynamics of controlled release mechanism under boundary friction

Abstract

Friction bounds the lower performance in control applications. Effective product modeling of controlling mechanisms and capturing the nonlinearity imposed by friction always attract the attention of researchers. Present work intends to capture the nonlinear dynamic behavior of a mechanical system with control release operation under boundary friction. The system used for this purpose is a second-order mechanical system comprising of rotary inertia element (lever), linear element (targeted mass), and spring element. The mechanical system chosen bears a resemblance to actual systems with control release like actuators, hydraulically operated copy turning machine, flight control mechanism, and robotics. The system dynamics have been captured under the light of two friction models viz. LuGre model and Dahl model. The performance of the system under these two friction models is ascertained for different times taken by the mass to settle, post and pre-zero-crossing time taken by target mass, maximum amplitude, time-period, and amplitude decay. The present work is capable of providing guidelines to simulate systems with control release under friction.

Keywords

• Friction
• Amplitude decay
• Settling time
• Forcing function
• Control release