Comparison of Joint Friction Estimation Models for Laboratory 2 DOF Double Dual Twin Rotor Aero-dynamical System

Abstract

Twin Rotor Aero-dynamical System (TRAS) include non-negligible nonlinearities due to frictions in the joints. In this study, joint frictions of the 2 DOF Double Dual Twin Rotor Aero-dynamical System (TDDTRAS) were estimated based on experimental data and simulation dynamic responses. Three different friction estimation models such as Non-Conservative, Linear, and a Non-linear friction models were compared to estimate the joint frictions of the (TDDTRAS) developed in our laboratory. Based on comparative experimental friction analysis, the joint frictions of the (TDDTRAS) are estimated better using Non-Linear friction model (NLFM). The mathematical model with NLFM is developed for simulation and controller. A robust dynamics model was obtained by the NLFM which will be used in the inverse dynamic model for the PID controller. PID controllers designed based on the mathematical model with nonlinear friction model. Accurate inverse model and the joint friction compensation improved PID controller performance for the TDDTRAS.