使用傾斜儀及加速計之指向裝置的定向控制

Direction Control of a Pointing System Using Inclinometers and Accelerometers

戴天適(Tian-Shi Dai)

指導教授 ： 馮蟻剛

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00196

摘要

海面上航行的船隻，無論其是否有動力想要運動，通常都是在動著，主要原因是無時不在變動的海浪所引起的。這和陸地上運動的車輛有很大的不同。尤其是在側向的運動上。陸地上的車輛因為靜止的陸地之緣故，一般是不容易作側向的運動的。而海上的船隻則依海浪的變化而變化。在本實驗室先前一系列的研究計畫中，當考慮陸地上的車輛如坦克，透過一些感測器，如傾斜儀或是加速規，以獲得其的姿態，將之回授至砲塔以追蹤目標，並且得以在行進間持續控制砲塔的位置，使其能順利擊中目標。然而當考慮海上行船的問題時，之前的模型就必須經過調整。藉由多加入它種的感測器，如加速規或是傾斜儀。可以獲得額外的資訊。由於傾斜與加速這兩種資訊是互相耦合在一起，因此新考慮的演算法須運用適當的數值分析，而得到較為正確的 “姿態” 資訊。此資訊以軟體及史都華平台實作模擬驗證，透過控制砲塔之測試可得到比不考慮加速度項更加精確的結果。

關鍵字

運動耦合 ； 海浪干擾 ； 史都華平台 ； 加速規 ； 傾斜儀

並列摘要

Abstract
Vessels moving on the ocean are constantly disturbed by waves no matter they are powered or not. This situation is different from that for the vehicle on the land. In previous researches, motion states of tanks are assumed to be available, and useful for controlling the turret to keep tracking targets. In contrast, when the same method is applied to control turrets or other pointers mounted on oceanic vessels, inaccuracy caused by the wave disturbance needs extra considerations, especially those due to the surge acceleration or sway acceleration of waves, which are orthogonal to the gravitational acceleration but can be measured by the inclinometers. They cause measurement errors with the inclinometers, as the tilt information is coupled with the translational accelerations. Therefore more sensors, preferably not expensive ones, are necessary to obtain more information, which when processed together by proper algorithms can generate accurate tilt data. With simulations and experiments implemented on a Stewart Platform based system, it is shown here that more correct motion state information of vessels subject to the above-mentioned disturbance can be obtained. Furthermore, feedback of the corrected sensor data does make pointers on the vessel track target position more precisely.

並列關鍵字

wave disturbance ； inclinometer ； Stewart Platform ； motion coupling ； accelerometer

參考文獻

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