人造衛星天線之轉動機構控制

Abstract

本文主要包含了人造衛星天線的自轉機構設計與自轉速度控制。 人造衛星根據通訊或任務需求，其天線的規格不盡相同，加上考慮載 具酬載空間限制，常常需要在發射前將天線進行折疊，發射送入太空 軌道後，將對天線作姿態控制。執行任務期間，被動微波偵測儀本身 有自轉的需求，但因運轉箱體與反射面之間有著許多可動與不可動元 件，自轉機構的設計成為了一項重大課題，本文研究使用迴轉接頭和 滑動環，設計衛星天線的旋轉平台；在馬達控制方面，因任務需要高 扭矩、低轉速的馬達，本文使用直驅馬達做控制，並利用PID 控制器 與順滑模態控制兩種方法，使其轉速維持在30RPM，並比較兩種方 法的優缺點以達到最佳的控制效果。

For satellite antennas, this thesis mainly deals with spin mechanism design and controls the spin rate of antennas in a radiometer. Based on communication or mission requirements, every satellite antenna has its own standard. Considering vehicle payload and space constraints, we need to fold the antenna before launch. After launching the satellite into an orbit, we will control the antenna attitude. During its mission, the radiometer itself has to rotate. Since the running between the box and the reflector has a lot of movable and immovable components, spin mechanism design has become a major issue. In this paper, we use the rotary joint and slip ring to design platform of the satellite antenna. In terms of motor control, the mission requires a high torque and low speed motor. This thesis uses a PID controller and a sliding mode controller to respectively control the velocity of a direct drive motor and make the radiometer rotate at 30RPM. We compare advantages and disadvantages of both methods in order to achieve the best control result.