Maximum-Payload Trajectories for a Laser-Propelled Launch Vehicle
Maximum-Payload Trajectories for a Laser-Propelled Launch Vehicle
复制标题
激光推进运载火箭的最大有效载荷轨迹
DOI：
10.2514/3.21539
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发表时间：
1995
影响因子：
2.6
通讯作者：
B. Pierson
中科院分区：
文献类型：
--
作者：
W. Humble;B. Pierson
激光推进运载火箭的可行轨道受到可用激光功率、大气吸收和光束传播损失以及推进器设计的限制。这些限制导致最佳轨道与常规运载火箭的轨道有很大不同。本文给出了一个采用脉冲激光推力器的运载火箭的问题公式和约束条件，并给出了两种激光功率传输模型。发射到各种圆轨道的最大有效载荷问题，解决了两个传输模型，使用序列二次规划。一个不寻常的后翼轨迹的功能，获得了大多数的最佳轨迹。讨论了各种圆形轨道高度的最佳轨道，并显示了改变功率传输效率的影响。ASER-PROPELLED运载火箭是在20世纪70年代初首次提出的。1自那时以来，激光和光学技术的进步增加了极高功率、地基、激光发射系统。2 '3这种系统每年有可能向低地球轨道（LEO）发射数千次，而且与目前使用的运载火箭相比，其成本大大降低。4坎特罗维茨提出了一种极其简单的方法，（因此也是廉价的）激光推进运载火箭的设计。如图1所示，该飞行器基本上是一个由某种固体推进剂构成的正圆锥体，其顶点处有一个有效载荷。圆锥形状允许运载工具相对于激光束转动，而不会将有效载荷暴露于激光。当被双脉冲激光束击中时，整个飞行器的底座就像Kare所描述的双脉冲平面推进器（DPPT）一样。4.低功率脉冲使推进器表面所需数量的推进剂蒸发，形成一层薄薄的气体。气体推进剂，然后加热的激光支持爆震（LSD）波发起和持续的第二个，高功率激光脉冲。热气体然后一维膨胀产生推力。
The feasible trajectories of a laser-propelled launch vehicle are restricted by the laser power available, the power lost to atmospheric absorption and beam spreading, and the thruster design. These constraints result in optimal trajectories that are significantly different from those for conventional launch vehicles. The problem formulation and constraints for a launch vehicle using a pulsed-laser thruster with two laser power transmission models are presented. A maximum payload problem for launch to various circular orbits is solved for both transmission models using sequential quadratic programming. An unusual backs wing trajectory feature is obtained for most of the optimal trajectories presented. The optimal trajectories for various circular orbit altitudes are discussed, and the effects of altering the power transmission efficiency are shown. ASER-PROPELLED launch vehicles were first proposed in the early 1970s.1 Advances in laser and optics technology since then have increased the feasibility of very high power, ground-based, laser launch systems.2'3 Such systems offer the potential of thousands of launches to low Earth orbit (LEO) per year at greatly reduced costs over current launch vehicles.4 Kantrowitz5 has proposed an extremely simple (and hence cheap) design for a laser-propelled launch vehicle. The vehicle is essentially a right circular cone of some solid propellant with a payload in the apex as shown in Fig. 1. The conical shape allows the vehicle to turn relative to the laser beam without exposing the payload to the laser. When struck by a double-pulsed laser beam, the entire base of the vehicle acts as a double-pulse planar thruster (DPPT) as described by Kare. 4 A low-power pulse evaporates a desired amount of propellant from the thruster surface to form a thin layer of gas. The gaseous propellant is then heated by a laser-supported detonation (LSD) wave initiated and sustained by a second, highpower laser pulse. The hot gas then expands one dimensionally producing thrust.