基于SDRE方法的小型无人直升机轨迹跟踪控制

Trajectory-tracking control for small unmanned helicopter based on SDRE

针对小型无人直升机姿态稳定及位置跟踪控制问题,提出了基于SDRE(state-dependent Riccati equation)的跟踪控制方法.首先,根据牛顿欧拉方程及刚体理论建立了包含主旋翼挥舞动态的14阶无人直升机动力学模型.其次,将直升机系统依次划分为位置环,速度环,姿态环,姿态角速率环和挥舞运动环,再对各环动力学方程进行等效变换使其满足特定条件.在此基础上,针对非仿射系统,考虑引入控制输入u的微分6)u,将u作为系统状态变量6)u作为新的控制输入.最后,将所提出的方法应用于Trex-250直升机.结果表明,所提方法能够取得良好的位置和姿态跟踪效果,且具有很好的实时性和鲁棒性.

Aiming at solving the problem of attitude stability and position tracking control of unmanned small scale helicopter,a state-dependent Riccati equation( SDRE) based trajectory tracking control method was proposed. Firstly,a 14 order dynamics model of the unmanned helicopter,including the main rotor flapping dynamic was established based on the Newton Euler equation and the rigid body theory. Secondly,the dynamics model was divided into a nested sequence of position,velocity,Euler angle,angular rate,and rotor dynamic loops,and equivalent transformations of the dynamics equation were made for each loop,rendering the system to satisfy specify conditions. On this basis,for a non-affine system,u,the differentiation of the control input u was introduced to be the new control input of the system,and u was regarded as the state variable. Finally,the proposed method was used for the Trex-250 helicopter. Simulation results show that the proposed method has better robustness and real-time performance on attitude and position control.