摘要：登陆火星或月球时,释放降落伞后进入推进阶段,通过轴向推力倾斜实现水平方向运动,能够与速度矢量(重力)的相反方向一致或与需要的加速度方向保持一致.后一种策略能实现精确着陆,在该策略下,倾斜角(俯仰角和偏转角)与水平加速度成正比.这种策略并未采用以水平加速度为姿态控制目标的递阶导航与控制方案,而是基于角加速度对位置作用的四阶动力学特性设计了一个独特的控制系统.除去倾斜角的非线性因素(垂直制动规定的轴向推力)后,系统综合动力学方程能够实现(准)输入-状态线性化.论文同时表明:一方面,基于参考轨迹(倾斜角和位置)的控制器设计仅能实现部分输入-状态线性化;另一方面,系统的内部稳定性可以证明.即使存在不可镇定的外部干扰动力学模态时,仍能确保系统稳定性.蒙特卡洛仿真验证了闭环控制策略的有效性.

摘要：The paper addresses the problem of reconciling the modern control paradigm developed by R. Kalman in the sixties of the past century, and the centenary error-based design of the proportional, integrative and derivative （PID） controllers. This is done with the help of the error loop whose stability is proved to be necessary and sufficient for the close-loop plant stability. The error loop is built by cascading the uncertain plant-to-model discrepancies （causal, parametric, initial state, neglected dynamics）, which are driven by the design model output and by arbitrary bounded signals, with the control unit transfer functions. The embedded model control takes advantage of the error loop and its equations to design appropriate algorithms of the modern control theory （state predictor, control law, reference generator）, which guarantee the error loop stability and performance. A simulated multivariate case study shows modeling and control design steps and the coherence of the predicted and simulated performance.