偏转弹头导弹的动力学建模方法研究

 偏转弹头是一种新的导弹操纵方式，动力学建模是对其研究的基础。偏转弹头导弹可以看成由弹头和弹体组成的多体系统，应用多体建模方法Schiehlen法建立系统的动力学模型。首先把弹头和弹体的运动状态用广义坐标表示，弹头的绝对运动由相对运动原理得到，根据牛顿 欧拉动力学方程分别写出弹头和弹体的质心移动方程和绕质心的转动方程，再运用达朗伯原理的理想约束性质消去方程中包含的约束力，同时方程的数目也减少到与系统的自由度数相同，从而得到维数与系统自由度数相同的二阶标量微分方程组。最后仿真验证模型，并分析得到偏转弹头导弹的一些特点，即偏转弹头导弹具有控制效率高，机动过载大，响应速度快等优点，是一种有效的快速响应控制方式。研究表明对于像偏转弹头导弹这类刚体数目少、但自由度数目较多的多体系统，其动力学建模适合使用Schiehlen法。

Study on Dynamics Modeling of Missile with Deflectable Nose

Deflectable nose is one alternative control method of missiles,and the dynamics modeling is the foundation of the research on it.Schiehlen's method is used for dynamics modeling of a missile with deflectable nose,which is a multi-rigid body system consisting of body and nose.First the motion states of missile body and nose are expressed with generalized coordinates, and the motion of nose is obtained using the relative motion relation.Then Newton-Euler equation is used for both missile body and nose,and the constraint force in the equations are eliminated using D'Alembert's principle,simultaneously the degree of the equations reduce as equal as the degree of freedom of the system.At last the dynamics modeling is validated by simulation and some characteristics of deflectable nose are analysed.The results indicate that the deflectable nose control provides high effectiveness and great maneuverability,and has a quick response.It has been shown that Schiehlen's method is well suited for multi-rigid body system such as nose control missiles,which have fewer components and more degrees of freedom.