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目前航天飞机的控制系统还不能防止轨道器主发动机的摆动对固体火箭助推器分离产生不利的影响。但在固体火箭助推器分离之前不久消除姿态误差和姿态变化率的反馈,可以减小轨道器主发动机的不利影响。此外,如采用角加速度反馈,轨道器发动机产生的摆动力矩就能减小气动力矩的不利影响。本文研究了此类控制技术,并比较了此类新开发的控制系统的分离能力。目前以最坏情况的初始条件和每次航天飞机系统都沿最坏的方向散布(比实际飞行中遇到的更保守)考虑,固体助推器与航天飞机外贮箱会有一个760mm的干扰间隙。消除姿态误差和姿态变化率反馈,可使其减小到483mm。若用角加速度反馈来替代,还可将其进一步减小到152mm。后两种情况的干扰可以通过较不保守的分析枝术,即通过系统散布之和的平方根来消除。
At present, the control system of the shuttle does not prevent the swinging of the main orbiter main engine from adversely affecting the separation of the solid rocket booster. However, the feedback of attitude error and attitude change rate shortly before the separation of the solid rocket boosters can reduce the adverse effects of the orbiter main engine. In addition, if angular acceleration feedback is used, the oscillating torque generated by the orbital engine can reduce the adverse effect of the aerodynamic torque. This paper studies such control techniques and compares the separation capabilities of such newly developed control systems. Given the worst-case initial conditions and the fact that each space shuttle system is spreading in the worst direction (more conservative than encountered in actual flight), there is a 760mm interference between the solid booster and the shuttle’s outer tank gap. Eliminate the attitude error and attitude change rate feedback, it can be reduced to 483mm. If angular acceleration feedback is used instead, it can be further reduced to 152mm. The latter two cases of interference can be eliminated by a less conservative analytical technique, ie, by the square root of the sum of systematic dispersions.