The dynamics of a twin-rotor multi-input multi-output system, which is similar to that of a helicopter in many ways, is highly nonlinear in nature. In this article, a detailed dynamical model of twin-rotor multi-input multi-output system is developed and simulated by using bond graph approach. Nonlinear nature of the interface gain, thrust, and drag forces, and the stiffness of cable attached to support column joint are estimated. The rotors are modeled through the Newton–Euler equations. The bond graph model is created by using the generic sub-models and the same set of sub-models can be assembled differently to model many other similar systems such as tricopters and quadcopters. Inertial forces and moments, rotor thrust and drag forces, active and reactive motor torques, and direct current motor dynamics are considered in the model. The responses from the model are compared with the test data for validation.

中文翻译：

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双转子系统的键合图建模与多体动力学

双旋翼多输入多输出系统的动力学在许多方面与直升机类似，本质上是高度非线性的。在本文中，使用键图方法开发和模拟了双转子多输入多输出系统的详细动力学模型。估计了界面增益、推力和阻力的非线性特性，以及连接到支撑柱接头的电缆的刚度。转子通过牛顿-欧拉方程建模。键图模型是通过使用通用子模型创建的，同一组子模型可以以不同的方式组装，以模拟许多其他类似的系统，例如三轴飞行器和四轴飞行器。模型中考虑了惯性力和力矩、转子推力和阻力、有功和无功电机扭矩以及直流电机动力学。