Forward/Reverse Attitude Solution and Specificity Analysis for Independent Pitch Control System of Coaxial Dual-Rotor Compound Helicopter.

The mechanical configuration of an independent pitch control system (IPCS) for coaxial dual-rotor compound helicopter (CDCH) was presented, which is mainly constituted by parallel mechanism, spatial orientation, lower rotor and upper rotor. The solving path and model division for the IPCS based on the working principle can be explained to achieve azimuth attitude precise control of upper and lower propeller for the CDCH. The completely mathematical model of attitude control system for the CDCH was obtained by using lumped parameters method and sub-total solution model which the forward and reverse positional attitude solution were deducted by the coordinate space transformation and kinematic analysis method. The co-simulation analysis which based on the MATLAB and Recurdyn software was done and the numerical comparative results show that the theoretical analysis of the mathematical model for attitude control system was reasonable and applicable by means of comparison with semi-physical model in the various boundary conditions and parameters of parallel mechanism, spatial orientation, lower rotor and upper rotor, respectively. [ABSTRACT FROM AUTHOR]