在二維平面上的發射載具導引與控制

Abstract

1957年以彈道飛彈火箭成功發射第一個衛星之後，迄今欲將衛星發射進入軌道，火箭仍是目前最常被使用的載具。利用持續的推力將火箭自身及酬載一同推入高空，並以多節的型式持續加速以節省燃料，以達進入規劃既定的軌道。一般而言，火箭分成三至四節，從地表開始以垂直或接近垂直的角度發射後，先利用重力轉彎，到了開始燃燒第二節火箭時才開始進行轉向，最後在第三至第四節火箭燃燒時，控制載具在軌道上加速，使其在預期的目標軌道上以正確的飛行方向和速度入軌。本論文是探討在二維平面上發射載具導引與控制的設計，從設計載具的物理參數和時間參數開始，其後控制火箭轉向，最後在入軌加速階段，先以「高度回授控制」使得軌道高度符合要求，再以「迫使平飛控制」使得飛行路徑角更符合要求，進入運行軌道，成功達成預期目標。

Since the first satellite launched successfully in 1957, rocket is by far the most frequently used vehicle to launch a payload into orbit for its continuous thrust to lift itself and the payload into the high altitude and its multi-stage mode of sustained acceleration to economize the use of propellant. Generally speaking, a rocket contains 3 to 4 stages. In the first stage, after launching vertically or near-vertically from the earth surface, gravity turn was used. Afterwards, the rocket can be steered into proper directions in proper time and positions after activating the second stage. Finally, the payload can be controlled to accelerate and enter the designated orbit with accurate direction and speed-of-flight in the last stages. The objective of this thesis is to investigate the design of launch vehicle guidance and control on 2D platform. It begins with designing the physical parameter and temporal parameter of rocket and then the control of steering and altitude. In the final acceleration stage of entering orbit, “altitude feedback control” is applied to meet the requirement of orbit altitude, and then “forced level flight control” is applied to meet the requirement of zero flight-path angle. Eventually, the payload propelled by the vehicle reaches the target orbit successfully.